Method for production of silicium dioxides, silicium dioxides with specific sizing and/or pore distribution and uses thereof, in particular in polymer reinforcement

FIELD: technology for silicium dioxide production useful as additive for polymer reinforcement.

SUBSTANCE: claimed method includes silicate reaction with acidifying agent to produce silicium dioxide slurry separation and drying of said slurry, wherein reaction is carried out according to the next steps: i) providing base aqueous solution with pH from 2 to 5, preferably from 2.5 to 5; ii) simultaneous addition silicate and acidifying agent to said base solution maintaining solution pH from 2 to 5, preferably from 2.5 to 5; iii) addition silicate only without acidifying agent to produce pH from 7 to 10, preferably from 7.5 to 9.5; (iv) simultaneous addition silicate and acidifying agent to reaction medium to maintain pH from 7 to 10, preferably from 7.5 to 9.5; (v) addition acidifying agent only without silicate to produce reaction medium pH below 6. Obtained high structured silicium dioxides have the next characteristics: CTAB specific surface (SCTAB) is 40-525 m2/g; BET specific surface (SBET) is 45-550 m2/g; width Ld ((d84-d16)/d50) of particle size distribution measured by XDC grading analysis after ultrasound grinding is at least 0.92; and such pore distribution that V(d95-d50)/V(d5-d100) is at least 0.66.

EFFECT: improved material for polymer reinforcement.

 

The present invention relates to a new method of obtaining silica, silica with a specific particle size distribution and/or distribution of pores, which, in particular, in the form of powder, practically spherical beads or granules, and to their application, such as applying for hardening polymers.

The use of white reinforcing additives to polymers, particularly elastomers, such as, for example, precipitated silicon dioxide, is known.

The objective of the invention is, in particular, to offer an alternative additive to polymer compositions with unusual properties, creating an excellent compromise, in particular, between their mechanical and dynamic properties, without sacrificing their rheological properties.

The invention relates, primarily, to a method for production of silicon dioxide, includes the interaction of the silicate with the acidifying agent to obtain a suspension of silicon dioxide, and then the separation and the drying of this suspension, characterized in that the reaction of the silicate with the acidifying agent is carried out according to the following successive stages:

(i) receive water base solution, the pH is from 2 to 5,

(ii) to the specified base solution simultaneously adding silicate and acidifying agent so that the pH of the reaction medium p which has derivate in the range of 2 to 5,

(iii) cease to add an acidifying agent, continuing to add the silicate to the reaction medium to obtain a pH of the reaction medium from 7 to 10,

(iv) in the reaction medium was added simultaneously silicate and acidifying agent so that the pH of the reaction medium was maintained in the range of 7 to 10,

(v) cease to add silicate, while continuing to introduce into the reaction environment acidifying agent to obtain a pH of the reaction medium below 6.

It was found that the consistent implementation of certain steps, in particular the first simultaneous administration of acidifying agent and silicate in an acidic environment with a pH of from 2 to 5 and the second simultaneous administration of acidifying agent and silicate in an alkaline environment with a pH of from 7 to 10, is an important condition for imparting product special characteristics and properties.

The choice of acidifying agent and of silicate is carried out by well known methods.

Usually as acidifying agent using strong inorganic acid, such as sulfuric acid, nitric acid or hydrochloric acid, or organic acid such as acetic acid, formic acid or carbonic acid.

Acidifying agent may be diluted or concentrated; its normality can be from 0.4 to 36 ad, for example from 0.6 to 1.5 N.

In particular, when admissi agent is sulfuric acid, its concentration may range from 40 to 180 g/l, for example from 60 to 130 g/L.

As the silicate can be used any conventional form of silicates, such as metasilicate, disilicate and, mainly, the alkali metal silicate, in particular sodium silicate or potassium.

The silicate may have a concentration (expressed as SiO2)constituting from 40 to 330 g/l, for example from 60 to 300 g/l, in particular from 60 to 260 g/l

Generally, as the acidifying agent used sulfuric acid, and silicate is sodium silicate.

When using sodium silicate, he usually has a weight ratio of SiO2/Na2O average of from 2.5 to 4, for example from 3.2 to 3.8.

Regarding the method of receiving according to the invention, more specifically, the reaction of the silicate with the acidifying agent is a very specific way according to the following steps.

In the beginning form the aqueous basic solution having a pH from 2 to 5.

Preferably, formed the basic solution has a pH from 2.5 to 5, in particular from 3 to 4.5; for example, its pH ranges from 3.5 to 4.5.

This initial basic solution can be obtained by adding acidifying agent to the water to get the pH of the base solution from 2 to 5, preferably from 2.5 to 5, in particular from 3 to 4.5, and, for example, from 3.5 to 4.5.

It can also be obtained doba is of acidifying agent to the mixture water+silicate, to obtain the same pH value.

It can also be prepared by adding acidifying agent to the base mud containing particles of silicon dioxide previously formed at a pH below 7, to obtain a pH value from 2 to 5, preferably from 2.5 to 5, in particular from 3 to 4.5, and, for example, from 3.5 to 4.5.

The basic solution formed in step (i)may optionally contain an electrolyte. However, it is preferable not to add any of the electrolyte during the process of obtaining, in particular at the stage (i).

The term "electrolyte" is understood here in its usual sense, that is, it means any ionic or molecular compound, which, when it is in solution, decomposes or dissociates with the formation of ions or charged particles. The electrolyte can be called a salt from the group of salts of alkali and alkaline earth metals, in particular the salt of the metal of the original silicate and acidifying agent, for example sodium chloride in the case of the reaction of sodium silicate with hydrochloric acid or, preferably, the sodium sulfate in the case of the reaction of sodium silicate with sulfuric acid.

The second stage (stage (ii)) is simultaneous addition of acidifying agent and of silicate, thus (in particular, when such flow rates)that the pH of the reaction medium was kept at 2 to 5, preferred is compulsory from 2.5 to 5, in particular, from 3 to 4.5, for example, from 3.5 to 4.5.

The simultaneous addition of predominantly carried out so that the pH of the reaction medium was always equal to (would differ by no more than ±0,2) pH obtained at the end of the initial stage (i).

Next on stage (iii) cease to add an acidifying agent, continuing to add to the reaction medium silicate to obtain the pH of the reaction medium comprising from 7 to 10, preferably from 7.5 to 9.5.

In this case, it may be appropriate to carry out immediately after step (iii) and, hence, immediately after the termination of addition of silicate maturation reaction medium, in particular, at pH obtained at the end of stage (iii), and usually with stirring; this maturation may, for example, can take from 2 to 45 minutes, in particular from 5 to 25 minutes, and preferably does not include any addition of acidifying agent, nor the addition of silicate.

After step (iii) and possibly maturing start a new simultaneous addition of acidifying agent and of silicate, thus (in particular, when such flow rates)that the pH of the reaction medium was kept at 7 to 10, preferably from 7.5 to 9.5.

This is the second simultaneous addition (stage (iv)) should be implemented in such a way that the pH value of the reaction medium was constantly equal (difference not breeches ± 0,2) the pH values obtained at the end of the previous stage.

It should be noted that between step (iii) and step (iv), for example, between, on the one hand, a possible maturation, following step (iii), and, on the other hand, step (iv), to the reaction medium can be added acidifying agent, and the pH of the reaction medium after the addition of acidifying agent is then from 7 to 9.5, preferably from 7.5 to 9.5.

Finally, at stage (v) cease to add silicate, continuing to add to the reaction medium acidifying agent to obtain a pH of the reaction medium below 6, preferably of 3 to 5.5, in particular, from 3 to 5, for example, from 3 to 4.5.

In these instances, after step (v) and, hence, immediately after termination of the addition of acidifying agent, to conduct the maturation reaction medium, in particular, at pH obtained at the end of stage (v), and usually under stirring; maturation may, for example, can take from 2 to 45 minutes, in particular from 5 to 20 minutes and preferably does not include any addition of acidifying agent, nor the addition of silicate.

Reaction chamber in which the reaction of the silicate with the acidifying agent, usually equipped with appropriate mixing and heating.

The reaction of the silicate with the acidifying agent is typically run at a temperature of from 70 to 95°C, cha is the mortality from 75 to 90° C.

According to one variant of the invention, the reaction of the silicate with the acidifying agent flow at a constant temperature, usually component from 70 to 95°C, in particular from 75 to 90°C.

According to another variant of the invention, the temperature at the end of the reaction is higher than the temperature at the beginning of the reaction: thus, the temperature at the beginning of the reaction (for example, steps (i) to (iii)support at the level of preferably from 70 to 85°C, then the temperature is increased, preferably to a value component from 85 to 95°C - values on which it is supported (for example, steps (iv) and (v)) until the end of the reaction.

At the end of the stages that were just described, get a paste of silicon dioxide, which is then sephirot (separation of liquid-solid).

The separation is carried out by the method of receiving according to the invention, typically includes filtration, optionally followed by washing. Filtering is carried out by any suitable method, for example, using a filter press, a bandpass filter, vacuum filter.

Allocated thus, the suspension of silicon dioxide (the residue from the filtration, then dried.

Drying can be carried out by any known method.

Preferably drying is carried out by sputtering. You can use any suitable type of sprayer, in particular t is runny spray, a nozzle with a nozzle, the nozzle pressure of the liquid or two liquids. When filtering is performed using a filter press, usually use a nozzle with a nozzle, and when the filtering is performed using a vacuum filter, use turbine spray.

It should be noted that the filter cake is not always in the circumstances, to allow spraying, especially because of its high viscosity. Then the precipitate in a known manner is subjected to the operation of separation. This operation can be performed mechanically, by passing the sludge through a colloid mill or ball type. Delamination usually occurs in the presence of aluminum compounds, in particular sodium aluminate and possibly in the presence of an acidifying agent, such as described above (in this latter case, the connection of aluminum and acidifying agent is usually added at the same time). The operation of separation significantly reduces the viscosity of the suspension for subsequent drying.

If drying is carried out using nozzles, the resulting silicon dioxide is usually in the form of almost spherical balls.

After drying, you can then proceed to step grinding of the selected product. Silicon dioxide, obtained in this case is usually in the form of powder.

If drying is carried out with the aid of the d turbine sprayer, silicon dioxide, obtained in this case may be in the form of a powder.

Finally, drained (in particular, by using a turbine sprayer or crushed, as mentioned above, the product may optionally be subjected to the agglomerating stage, which consists, for example, direct compression, wet granulation method (i.e. using a binder, such as water, the suspension of silicon dioxide and so on), extrusion or, preferably, by dry pressing. When using this latter method, it is advisable before pressing to carry out deaeration (surgery, also called pre-seal or degassing) powdered products to remove the contained air and provide a more uniform pressing.

Silicon dioxide obtained by this stage sintering is usually in the form of granules.

Powders, as well as balls of silicon dioxide, obtained by the process according to the invention have in addition the advantage that it allows to obtain granules simple, efficient and cost effective manner, in particular, classic molding operation, such as, for example, granulation or extrusion, and these operations do not entail destruction, able to disguise and even destroy the good properties is a, inherent in these powders or beads, as it can happen in the known methods using classical powders.

The method of receiving according to the invention allows, in particular, to obtain silica, type precipitated silica, which, on the one hand, are highly structured and not loose, and, on the other hand, have generally good ability to dispersion (dispersibility) in polymers, receiving an excellent combination of properties, in particular the dynamic and mechanical properties (in particular, good reinforcing effect and very high abrasion resistance), without sacrificing their rheological properties. The obtained silica should preferably have a specific particle size distribution and/or distribution of pores.

Silica, which can be obtained by the method of the invention, represent one aspect of the present invention.

Another object of the invention are new silica, type precipitated silica, which are highly structured and which have a particular particle size distribution and/or pore distribution; in addition, they have generally good ability to disperse (i.e., the dispersibility in polymers, which creates an excellent combination of properties, in particular their dynamic properties (in h is particularly reducing energy dissipation during deformation (low effect Payne), low loss hysteresis at high temperature (in particular, the decrease in the tan Delta at 60°C)), without sacrificing their rheological properties and, hence, without compromising their ability to process/forming (for example, a lower initial viscosity at specific isosurfaces), and have good mechanical properties, in particular good effect of strengthening, especially in relation to the modules, and a very high resistance to abrasion, resulting in improved durability of the finished products on the basis of these polymers.

In the following description, the values of the specific surface according to BET determined by the method of brunauer-Emmett-teller described in "The Journal of the American Chemical Society, vol.60, p.309, February, 1938, in accordance with the international standard ISO 5794/1 (Appendix D).

Specific surface area for adsorption of CTAB is an external surface defined by standard NF T 45007 (November 1987) (5.12).

Malopolskie (absorption DOP) is determined according to standard NF T 30-022 (March 1953) using dioctylphthalate.

The pH value measured in accordance with ISO 787/9 pH (5%suspension in water).

Method XDC grain-size analysis by centrifugal sedimentation, by which measure, on the one hand, the width of the size distribution of particles from which ioxide silicon, and, on the other hand, view XDC illustrating the particle size, as described below.

The necessary material

- granulometer with centrifugal sedimentation BI-XDC (BROOKHAVEN-INSTRUMENT X DISC CENTRIFUGE), supplied by Brookhaven Instrument Corporation);

- cylindrical chemical beaker of 50 ml volume;

- the beaker of 50 ml volume;

- ultrasonic probe BRANSON, 1500 watts, without attachments, with a diameter of 13 mm;

- deionized water;

the mold filled with ice;

- magnetic stirrer.

Measurement conditions;

the DOS version 1.35 software (provided by the designer granulometry);

- fixed fashion;

- the analysis duration: 120 minutes;

- density (silicon dioxide): 2,1;

- the volume of the suspension, selected for analysis: 15 ml

Sample preparation

Add in a cylindrical chemical glass of 3.2 g of silicon dioxide and 40 ml of deionized water.

To place a chemical beaker containing the suspension in the mold filled with ice.

Immerse ultrasonic probe in chemical glass.

To crush a suspension for 16 minutes with 1500-watt BRANSON probe (using 60% of maximum power).

When the melting of the ends, put a chemical beaker on the magnetic stirrer.

Cooking granulometry

Turn on the device and heat for 30 minutes.

Rinse the disk 2 times Deyo savannas water.

Enter in the disk 15 ml sample for analysis and to enable mixing.

To enter the measurement conditions specified above.

To make measurements.

When the measurements are performed:

To stop the rotation of the disk.

Rinse several times the disk deionised water.

Switching off the device.

Results

The device records the values of the diameters of the transmission 16%, 50% (or the middle) and 84% (weight. %), as well as the importance of Fashion (the derivative of the integral particle size distribution curve gives a frequency response curve, the maximum x-coordinate (abscissa of the General population) is called the mode).

The width Ld of the distribution of particle size, measured by XDC granulometry after grinding ultrasound (in water)is determined by relation (d84-d16)/d50, where dn is the size at which n % of the particles by weight have a size less than a given width Ld distribution in this case is calculated throughout the integral particle size distribution curve).

Width L′d distribution of particle sizes less than 500 nm, measured by XDC-particle size after grinding ultrasound (in water), is calculated according to relation (d84-d16)/d50, where dn is the size at which n % of particles (by mass), with respect to particle size less than 500 nm, have a size below this (i.e. the width L′d distribution is calculated by the integral granulometric the tion curve, cropped above 500 nm).

In addition, the method XDC grain-size analysis with a centrifugal sedimentation is possible to measure the average (by weight) particle size of silicon dioxide (i.e., secondary particles or aggregates), denoted by dwafter dispersion by grinding ultrasound, silicon dioxide in water. This method differs from that described above so that the formed suspension (silica + deionized water) was reserches, first, for 8 minutes, and secondly, using a VIBRACELL ultrasonic probe (1.9 cm produced by the company bioblock is used), 1500 watts (using 60% of maximum capacity). After analysis (sedimentation for 120 minutes) the weight distribution of particle sizes is calculated by the program granulometry. Srednevekovoi geometric particle size ("geometric mean (Xg)" according to the term software), denoted by dwcalculated by the program according to the following equation:

logdw=(Σ(i=1 to i=n)milogdi)/(Σ(i=1 to i=n)miwhere mithere are many combinations of the objects in the class dimension di.

Given the volume of pores measured by mercury porometry; preparation of each sample is performed as follows: each sample previously dried for 2 hours in a drying Cabinet at 200°C, then placed in p is amnic samples five minutes after leaving the drying chamber and Tegaserod under vacuum, for example, using a pump with rotary valve; pore diameters (Porosimeter MICROMERITICS Autopore III 9420) calculated as ratio of Washburn when contact angle theta equal to 140°and a surface tension gamma equal to 484 Dyne/cm or n/m).

V(d5-d50)represents the pore volume formed by pores with diameters components from d5 to d50, and V(d5-d100)represents the pore volume formed by pores with diameters from d5 to d100, and dn is the diameter of the pores, for which n % of the total surface of all of the pores formed by pores with a diameter above this diameter (full surface of the pore (S0) can be determined by curve indentation of mercury).

Width of pore distribution Idp emerges from the distribution curve of the pore, as shown in the drawing, which shows the volume of pores (ml/g) as a function of pore size (nm): in order to know the value of the diameter (nm) Xsand pore volume (ml/g) Ys,put the coordinates of the point S corresponding to the main population; draw straight line with equation Y=Ys/2; this line intersects the curve of pore distribution in two points A and B on opposite sides of the Xswith x (nm) XAand XBrespectively; the width of pore distribution Idp is equal to the ratio (XA-XB)/Xs.

In certain cases, the ability to disperse (and crushing) of the silica with the according to the invention can be quantified with the help of special tests for crushing.

One of the tests on the chopping is performed in the following order:

Bond strength of agglomerates evaluated by particle size distribution measurement by laser diffraction radiation), carried out on suspensions of silicon dioxide, previously pulverized by ultrasonic irradiation; measure also the ability to melting of silicon dioxide (separation of particles from 0.1 to several tens of microns). Chopping ultrasound is carried out using ultrasonic irradiator VIBRACELL bioblock is used (600 W), equipped with a probe with a diameter of 19 mm particle size measurement is carried out using diffraction of laser radiation on granulometry SYMPATEC.

In a machine for making pills (height 6 cm and 4 cm in diameter) weighed 2 grams of silicon dioxide and complement up to 50 grams by adding deionized water: receive aqueous suspension with 4% silicon dioxide, which is homogenized for 2 minutes using a magnetic stirrer. Then make chopping ultrasound as follows: the probe is immersed to a depth of 4 cm, mounted on this output power to obtain the deviation of the arrow indicator power, showing 20%. Crushing is carried out in a period of 420 seconds. Then, after the tank granulometry put a known volume (expressed in ml) of the homogenized suspension, out granulometry the definition of the dimension.

Get the value of the mean diameter ⊘50S(or average diameter Sympatec) is the lower, the higher the ability of silicon dioxide to reduce them. You can also define the relation (10×volume (in ml) is added to the suspension)/optical density of the suspension, as determined in granulometry (this optical density is about 20). This ratio shows the proportion of particles below 0.1 µm, which are not detected by granulometry. This ratio is called the coefficient of grinding (Sympatec) ultrasound (FDS).

Another test on the chopping is performed in the following order:

The bond strength of the agglomerates is measured by particle size distribution measurement (diffraction of laser radiation), carried out on suspensions of silicon dioxide, pre-crushed by exposure to ultrasound; measure the ability of silica to crushing (separation of particles from 0.1 to several tens of microns). Chopping ultrasound is carried out using ultrasonic irradiator VIBRACELL bioblock is used (600 watts)operating at 80% of maximum capacity, equipped with a probe with a diameter of 19 mm particle size measurement is carried out using diffraction of laser radiation on granulometry Malvern (Mastersizer 2000).

In a machine for making pills (height 6 cm and 4 cm in diameter) weigh 1 gram of dioxi is as silicon and complement up to 50 grams by adding deionized water: get a water slurry with 2% silicon dioxide which is homogenized for 2 minutes by stirring with a magnetic stirrer. Then spend chopping ultrasound for 420 seconds. Then, after you enter in the bath granulometry all gomogenizirovannogo suspension, conduct particle size distribution measurement.

The obtained value of the median diameter ⊘50M(or the average diameter of the Malvern) the smaller, the higher the ability of silicon dioxide to reduce them. You can also define the relation (10×the amount of darkening blue laser)/value darkening of the red laser. This ratio indicates the percentage of particles below 0.1 µm. This ratio is called the coefficient of grinding (Malvern) ultrasound (FDM).

Speed grinding, denoted by αcan be measured by another test on the chopping ultrasound, with 100%power of a 600 watt transmitter operating in the pulse mode (ie: 1 second on, 1 second off), to avoid excessive heating of the ultrasonic probe during measurement. This well-known test, which was, in particular, the subject application WO 99/28376 (see also application WO 99/28380, WO 00/73372, WO 00/73373), makes it possible to continuously measure the change in the average size (by volume) of the agglomerates of particles in the processing of ultrasound, according to the following steps. Used the system consists of a laser g is bolometer (type "MASTERSIZER S", produced by Malvern Instruments - laser source He-Ne, emitting in the red range, wavelength 632.8 nm) and the technician ("Malvern Small Sample Unit MSX1"), between which was inserted cell for processing in a continuous flow (bioblock is used M72410), equipped with an ultrasonic probe (ultrasonic irradiator 12.7 mm type VIBRACELL, 600 watt, the production company bioblock is used). In the preparator with 160 ml of water injected a small amount (150 mg) analyzed silicon dioxide, and the circulation rate set to maximum. Spend at least three consecutive measurements to determine by known calculation method Fraunhofer (estimated matrix Malvern 3$$D) initial average volume diameter of agglomerates, denoted by dv[0]. Then sonication (in pulse mode: 1 on 1 s off.) transferred to 100%capacity (i.e. 100% of the maximum position type "amplitude") and for about 8 minutes monitor changes in average volume diameter dv[t] as a function of time "t" on the basis of one dimension of about 10 seconds. After the induction period (about 3-4 minutes) find that the inverse of the average volume diameter, 1/dv[t]varies linearly or almost linearly with time t (stationary regime grinding). Speed grinding is calculated by a linear regression curve change is of 1/d v[t] as a function of time "t" in the zone of steady state grinding (usually about 4 to 8 minutes); it is expressed in μm-1min-1.

The aforementioned application WO 99/28376 describes in detail the measuring device that can be used to implement this test for crushing ultrasound. The device is a closed loop, which can circulate the flow of agglomerates of particles in suspension in the liquid. This device consists primarily of a device for sample preparation, laser granulometry and cells for processing. The application of atmospheric pressure in the apparatus for sample preparation and cell processing allows you to continuously remove air bubbles that are formed during exposure to ultrasound (ultrasonic probe). Device for sample preparation ("Malvern Small Sample Unit MSX1") is intended to select a sample of silicon dioxide for testing (in the form of a suspension in a liquid) and in order to make it move along the contour with a predetermined speed (potentiometer - maximum rate of about 3 l/min) in the form of a stream of liquid suspension. This device is simply a foster reservoir, which contains and through which circulates the analyzed suspension. It is equipped with a motor for mixing with variable speed to avoid wasp is the origin of agglomerates of particles of the suspension; centrifugal mini-pump is designed to circulate the slurry in the circuit; the device is connected with the air through the hole intended to receive the sample of filler and/or liquid, used for suspension. To the device connected laser granulometer ("Mastersizer S")whose function is continuous dimension, with equal time interval, the average volume size "dv" agglomerates with the passage of flow through the measuring cell, is attached to the logger and automatic calculation of granulometry. Let us briefly recall that laser particle sixers utilize the principle of light diffraction of solid objects in suspension in the medium, the refractive index of which differs from the refractive index of the solid. According to theory of Fraunhofer there is a correlation between the size of the object and the angle of diffraction of light (the smaller the object, the larger the diffraction angle). In practice, it is sufficient to measure the amount of light rejected by the different angles of diffraction in order to determine the distribution of the sample by size (volume), and dvcorresponds to medium-volume size distribution (dv=∑(nidi4)/∑(nidi3), where nimeans the number of particles belonging kanamu class size or diameter d i). Finally, between the device and a laser granulometer inserted cell for processing, equipped with an ultrasonic probe that can operate in continuous or pulsed mode, designed for continuous crushing of agglomerates of particles in the flow. This thread is thermostated by means of a cooling circuit located at the cell level, in the form of a double jacket surrounding the probe, and the temperature is controlled, for example, a temperature probe immersed in the liquid level device.

The number of Sears is determined according to the method described G.W.SEARS article in "Analytical Chemistry, vol.28, No.12, December 1956, entitledof specific surface area of colloidal silica by titration with sodium hydroxyde (Determination of the specific surface area of colloidal silica by titration with sodium hydroxide).

The number of Sears is the volume of 0.1 M sodium hydroxide solution required to increase from 4 to 9 pH of a suspension of silicon dioxide concentration of 10 g/l in the medium of sodium chloride concentration of 200 g/L.

To do this, prepare, on the basis of 400 grams of sodium chloride, the sodium chloride concentration of 200 g/l, acidified to pH 3 with hydrochloric acid concentration of 1 M, the Weighting is done using the analytical balance METTLER. Carefully add 150 ml of this solution chlorine the buffer of net sodium in chemical beaker of 250 ml, in the previously introduced mass M (in g) of the analyzed sample, corresponding to 1.5 grams of dry silica. The resulting dispersion is treated with ultrasound for 8 minutes (BRANSON ultrasonic probe, 1500 W, the amplitude of 60%, diameter 13 mm), and chemical glass is in the mould filled with ice. Then the resulting solution was homogenized, stirring with magnetic stir bar, using a rod magnet dimensions 25 mm×5 mm Check that the pH of the suspension is below 4, adjusting it if necessary, a 1 M solution of hydrochloric acid. Then add using pH-micrometre Metrohm (title processor model 672, Dosimat 655), previously calibrated using buffer solutions of pH 7 and pH 4, 0.1 M solution of sodium hydroxide at a rate of 2 ml/min (pH tetramer programmed as follows: 1) Call the program "Get pH to Obtain pH), 2) Enter the following parameters: pause (waiting time before titration): 3, speed reagent: 2 ml/min, the expectation (ajust the speed of titration the slope of the curve pH): 30, stop pH: 9,40, critical TE (equivalence point) (sensitivity check the equivalence point): 3, report parameters, expressing the titration): 2,3,5 (i.e., creating a drillthrough report, a list of measurement points, titration curve)). By interpolation, determine the exact volume of the we V 1and V2the sodium hydroxide solution is added to obtain pH 4 and pH 9, respectively. The number of Sears for 1.5 grams of dry silica is equal to ((V2-V1)×150)/(ES×M), where:

V1: volume of 0.1 M sodium hydroxide solution at pH1=4,

V2: volume of 0.1 M sodium hydroxide solution at pH2=9,

M: mass of sample (g),

ES: dry extract in %.

The width of the distribution of pore sizes may also optionally be characterized by the parameter L/IF defined mercury porometry. The measurement is done using Porosimeter PASCAL 140 and PASCAL 440 production ThermoFinnigan; act as follows: a number of sample weighing from 50 to 500 mg (in this case, 140 mg) was injected into the measuring cell. This measuring cell is put in place to measure PASCAL device 140. The sample was then Tegaserod under vacuum during the time required to achieve a pressure of 0.01 kPa (usually about 10 minutes). Then the measuring cell is filled with mercury. The first part (pressure below 400 kPa) curve intrusion of mercury Vp=f(P), where Vp is the volume intrusively mercury, and P is the applied pressure, is determined by porosimetry PASCAL 140. Then the measuring cell is placed on the measurement site of porosimetry PASCAL 440, and the second part of the curve of the intrusion of mercury Vp=f(P) (pressure range from 100 kPa to 400 MPa) is determined by prosim the true PASCAL 440. Porosimetry used in the "PASCAL", to constantly adjust the speed of the intrusion of mercury depending on the change of volume of the intrusion. The speed parameter in the "PASCAL" is set to 5. The pore radii Rp calculated from the values of pressure P using the proportion of Washburn assuming cylindrical pores, choosing a contact angle theta equal to 140°and a surface tension gamma equal to 480 Dyne/cm or n/m). The volume then Vp is related to the mass of the introduced silicon dioxide and is expressed in cm3/, Signal Vp=f(Rp) is smoothed by combining the logarithmic filter (the filter option to "smooth attenuation factor" (F=0,96) and filter with the average movement filter parameter "number of points for averaging f=20). The distribution of the pore sizes obtained by calculating the derivative of the dVp/dRp smoothed curve intrusion. The coefficient of sharpness IF there is the pore radius (expressed in angstroms)corresponding to the maximum of the distribution of pore sizes dVp/dRp. The value of provisory distribution of pore sizes dVp/dRp denote L.

The number of silanol groups at 1 nm2the square is determined by the inoculation of methanol to the surface of the silicon dioxide. First, 1 g of untreated silica suspension in 10 ml of methanol in an autoclave with a volume of 110 ml (Top Industrie, standard 09990009). Enter the magnetic rod and the autoclave sealed thermoisolierung, heated at 200 °C (40 bar) and under stirring with a magnetic stirrer for 4 hours. Then the autoclave is cooled in a cold water bath. Grafted silica is separated by decantation and the residual methanol is evaporated in a stream of nitrogen. Finally, the grafted silica dried at 130°C under vacuum for 12 hours. The carbon content is determined by the analyzer elements (analyzer NCS 2500 production CE Instruments) on an untreated silicon dioxide and grafted on the silica. Quantitative analysis of grafted silicon dioxide is carried out through three days after the end of drying, and air moisture or heat can actually cause the hydrolysis of the grafted methanol. The number of silanol groups at 1 nm2thus is calculated by the following formula:

where %Cg: the weight percentage of carbon present in the grafted silicon dioxide,

%Cb: the weight percentage of carbon present in the raw silicon dioxide,

SBET: specific surface area of silicon dioxide on BET (m2/g).

Thus, according to the first variant of the invention proposes a new silicon dioxide, characterized in that it has:

- specific surface area CTAB (SCTAB)constituting from 40 to 525 m2/g

- specific surface according to BET (SBET )comprising from 45 to 550 m2/g

- width Ld ((d84-d16)/d50) of the distribution of particle sizes measured by the grading of the XDC after grinding ultrasound, at least 0.91, in particular at least equal to 0.94, and

the distribution of the pore volume, depending on the pore size, wherein the ratio of V(d5-d50)/V(d5-d100)well at least 0,66, in particular at least 0,68.

In particular, silicon dioxide according to this variant of the invention has:

- width Ld ((d84-d16)/d50) of the distribution of particle sizes measured by the grading of the XDC after grinding ultrasound equal to at least the 1.04 and

the distribution of the pore volume, depending on the pore size, wherein the ratio of V(d5-d50)/V(d5-d100)well at least 0,71.

This silicon dioxide may be relevant V(d5-d50)/V(d5-d100)at least 0,73, in particular, at least 0,74. This ratio may be at least 0,78, in particular, at least 0,80, even at least 0,84.

The second variant of the invention represents a new silicon dioxide, characterized in that it has:

- specific surface area CTAB (SCTAB)constituting from 40 to 525 m2/g

- specific surface according to BET (SBET)comprising from 45 to 550 m2/g

- wide distribution of pore Idp above 0.70 and, more specifically, is use 0,80, in particular, higher 0,85.

This silicon dioxide may have a width of pore distribution Idp above 1,05, for example, higher 1,25 even higher 1,40.

According to this variant of the invention the silicon dioxide preferably has a width Ld ((d84-d16)/d50) of the distribution of particle sizes measured by the grading of the XDC after grinding ultrasound, at least 0.91, in particular at least equal to 0.94, for example, at least equal to 1.0.

According to the third variant of the invention, a new silicon dioxide, characterized in that it has:

- specific surface area CTAB (SCTAB)constituting from 40 to 525 m2/g

- specific surface area BET (SBET)comprising from 45 to 550 m2/g

- wide L′d ((d84-d16)/d50) size distribution of particles less than 500 nm, measured by the grading of the XDC after grinding by ultrasound, is at least equal to 0.95 and

the distribution of the pore volume, depending on the pore size, wherein the ratio of V(d5-d50)/V(d5-d100) is at least 0,71.

This silicon dioxide may be relevant V(d5-d50)/V(d5-d100)at least equal to 0.73, in particular at least equal to 0.74. This ratio may be at least equal to 0.78, in particular at least equal to 0.80, even be not less 0,84.

The fourth variant of the invention represents a new diox the d silicon, characterized in that it has:

- specific surface area CTAB (SCTAB)constituting from 40 to 525 m2/g

- specific surface according to BET (SBET)comprising from 45 to 550 m2/g

- of a width L'd ((d84-d16)/d50) size distribution of particles less than 500 nm, measured by the grading of the XDC after grinding ultrasound, at least 0.90, in particular at least equal to 0.92, and

the distribution of the pore volume, depending on the pore size, wherein the ratio of V(d5-d50)/V(d5-d100)that is at least 0,74.

This silicon dioxide may be relevant V(d5-d50)/V(d5-d100)at least equal to 0.78, in particular at least equal to 0.80, even at least equal 0,84.

The silica according to the invention (i.e., the corresponding one of the four variants of the invention) pore volume formed by the largest pores is usually the largest part of the structure.

They can have a width Ld of the distribution of particle sizes at least equal to 1.04 million, and the width L d distribution of particle sizes less than 500 nm, equal to at least 0,95.

The width of the Ld size distribution of particles of silicon dioxide according to the invention may in certain cases be at least equal 1,10, in particular at least equal to 1.20; it can be equal to ENISA least 1,30, for example, at least 1,50, even be not less than 1,60.

Also, the width L d distribution of particle sizes less than 500 nm of the silica according to the invention can be, for example, equal to at least 1.0, more specifically, at least 1,10, in particular, at least 1,20.

Preferably, the silica according to the invention have a special chemical surface, according to which the ratio of (the number of Sears×1000)/(specific surface area by BET (SBET)) is below 60, preferably below 55, for example below 50.

The silica according to the invention have generally increased and, therefore, atypical particle size, which can be that the fashion of their size distribution, measured by the grading of the XDC after grinding ultrasound (in water)meets the condition: Fashion XDC (nm)≥(5320/SCTAB(m2/g))+8, even condition: Fashion XDC (nm)≥(5320/SCTAB(m2/g))+10.

The silica according to the invention can have, for example, pore volume (V80)formed by pores with diameters components from 3.7 to 80 nm, equal at least to 1.35 cm3/g, in particular at least 1,40 cm3/g even at least 1.50 cm3/year

The silica according to the invention preferably have a satisfactory ability to dispersion (dispersibility) in the floor of the measures.

Their average diameter (⊘50Safter grinding the ultrasound is usually below 8.5 μm; it may be below 6.0 μm, for example less than 5.5 microns.

Their average diameter (⊘50Mafter grinding the ultrasound is usually below 8.5 μm; it may be below 6.0 μm, for example less than 5.5 microns.

They may also have speed grinding αmeasured in test for crushing ultrasound in pulsed mode, described previously, at 100%power ultrasonic 600 watt probe to at least 0,0035 μm-1min-1in particular, at least equal 0,0037 μm-1min-1.

The silica according to the invention may have a ratio of crushing ultrasound (FDS) above 3 ml, in particular above 3.5 ml, in particular higher than 4.5 ml.

Their crushing ratio ultrasound (FDM) can be higher than 6, more specifically greater than 7, in particular higher than 11.

The silica according to the present invention can have an average (by weight) particle size measured by the grading of the XDC after grinding ultrasound, dwconstituting from 20 to 300 nm, in particular from 30 to 300 nm, for example from 40 to 160 nm.

Typically, the silica according to the invention also have at least one or even all three of the following characteristics:

the distribution of particle sizes such that dw≥(16500/SCTA is )-30

- porosity such that L/IF≥-0,0025SCTAB+0,85

- the number of silanol groups per unit surface areasuch that

According to one embodiment, the silica according to the invention typically have:

- specific CTAB surface, comprising from 60 to 330 m2/g, in particular from 80 to 290 m2/g

- specific surface according to BET of $ 70 to 350 m2/g, in particular from 90 to 320 m2/year

Their specific surface area CTAB can be from 90 to 230 m2/g, in particular from 95 to 200 m2/g, for example, from 120 to 190 m2/year

Their specific surface area by BET can range from 110 to 270 m2/g, in particular from 115 to 250 m2/g, for example, from 135 to 235 m2/year

According to another embodiment, the silica according to the invention typically have:

- specific CTAB surface constituting from 40 to 380 m2/g, in particular from 45 to 280 m2/g

- specific surface according to BET of $ 45 to 400 m2/g, in particular from 50 to 300 m2/year

Their specific surface area CTAB can be from 115 to 260 m2/g, in particular from 145 to 260 m2/year

Also, their specific surface area by BET can range from 120 to 280 m2/g, in particular from 150 to 280 m2/year

The silica according to the SNO present invention may have a certain microporosity; thus, the silica according to the invention is usually such that (SBET-SCTAB)≥5 m2/g, in particular, ≥15 m2/g, for example, ≥25 m2/year

This microporosity usually not very large; the silica according to the invention, as a rule, such that (SBET-SCTAB)<50 m2/g, preferably <40 m2/year

The pH value of the silica according to the invention typically ranges from 6.3 to 7.8, in particular, between 6.6 and 7.5.

They have different size Malopolskie DOP, mostly from 220 to 330 ml/100 g, for example, from 240 to 300 ml/100 g

They can be in the form of almost spherical beads with an average size of at least 80 microns.

This medium size balls may be at least 100 μm, for example, at least 150 μm; he also, as a rule, does not exceed 300 μm and preferably ranges from 100 to 270 μm. This average size is determined according to the standard NF X 11507 (December 1970) by dry sieving substances with the definition of a diameter corresponding to the harvested 50%of the resultant residue on a sieve.

The silica according to the invention can also be in the form of a powder with an average size of at least 15 μm; for example, size, comprising from 15 to 60 μm, in particular from 20 to 45 μm) or from 30 to 150 μm, in particular from 45 to 120 μm).

They may also be in view of the granules of a size not less than 1 mm, in particular the size, comprising from 1 to 10 mm, under the direction of their largest dimension (length).

The silica according to the invention preferably receive according to the method of obtaining corresponding to the invention described above.

The silica according to the invention or obtained by the process according to the invention finds a particularly interesting application to enhance natural and synthetic polymers.

Compositions based on polymer (polymers), in which they are used, in particular as reinforcing additives are usually compositions based on one or more polymers or copolymers, in particular one or more elastomers, in particular thermoplastic elastomers having, preferably, at least one glass transition temperature, which is from -150 to +300°C, for example, from -150 to +20°C.

As possible polymers can be called diene polymers, in particular diene elastomers.

For example, it is possible to use polymers or copolymers derived from aliphatic or aromatic monomers containing at least one unsaturated bond (such as, in particular, ethylene, propylene, butadiene, isoprene, styrene), polymethylacrylate, or mixtures thereof; may also be called silicone elastomers, functionalized elastomers (n is an example, groups suitable for interaction with the surface of the silicon dioxide and halogenated polymers. Mention can be made of polyamides.

The polymer (copolymer) may be a polymer (copolymer)obtained by polymerization in mass, the latex polymer (copolymer) or a solution of polymer (copolymer) in water or in any other suitable dispersing liquid.

As the diene elastomers, mention can be made of, for example, polybutadienes (Bq), polyisoprene (IR), copolymers of butadiene, copolymers of isoprene, or mixtures thereof, and, in particular, butadiene-styrene copolymers (BSC, in particular e-BSC (emulsion) or P-BSC (solution)), copolymers of isoprene with styrene (BIC), copolymers of isoprene with styrene (CLAIMS), copolymers of isoprene-butadiene-styrene (IBSC), ternary copolymers of ethylene-propylene-diene (EPDM).

You can also call natural rubber (TC).

Polymeric compositions may be vulcanized grey (so get the vulcanizates) or crosslinked, in particular, peroxides.

Typically, the compositions of the polymer(s) include, in addition, at least one binding agent (silicon dioxide/polymer) and/or at least one covering agent; they can also contain, optionally, one antioxidant.

As binding agents can in particular be used as non-limiting examples: polycarbosilane, t is called "symmetric" or "asymmetric"; you can specify more specifically, the polysulphides (in particular, disulfides, trisulfide or tetrasulfide) bis-(alkoxy(C1-C4)alkyl(C1-C4)silyl-Akilov(C1-C4)), such as polysulfides bis(3-(trimethoxysilyl)propyl) or polysulfides bis(3-(triethoxysilyl)propyl). You can also call tetrasulfide of monomethoxypolyethylene.

The binding agent may be pre-coated in the polymer.

It can also be used in a free state (i.e., without prior vaccination) or grafted to the surface of the silicon dioxide. The same applies to the possible covering agent.

The use of silicon dioxide according to the invention or obtained by the process according to the invention may allow significantly reduce, for example, about 20%, the amount of binding agent used in polymer compositions, reinforced by silicon dioxide, while maintaining complex properties are almost identical.

Together with the binding agent may be in some cases used suitable "activator binding", i.e. a compound which is mixed with a binding agent increases the effectiveness of the latter.

The weight percentage of silicon dioxide in the composition of the polymer(s) may vary within a wide range. It is usually from 20 to 80%, for example, the R from 30 to 70%, from the amount of polymer(s).

Silicon dioxide according to the invention may predominantly represent the entire reinforcing inorganic additive and even the entire reinforcing additive to the composition of the polymer(s).

However, this silicon dioxide according to the invention can be optionally added at least one reinforcing additive, in particular a commercially available highly dispersed silicon dioxide, such as, for example, Z1165MP, Z1115MP, besieged processed silicon dioxide (e.g., "activated" using a cation such as aluminum), other inorganic reinforcing additive, such as aluminum oxide, or organic reinforcing additive, in particular soot (optionally covered with an inorganic layer, such as silicon dioxide). Silicon dioxide according to the invention is in this case preferably at least 50% or at least 80% by weight of the entire reinforcing additives.

As non-limiting examples of finished products on the basis of the polymer compositions described above (in particular, on the basis of the vulcanizates mentioned above), you can call the soles of shoes (preferably obtained in the presence of a binding agent (silicon dioxide/polymer)), coatings for soils, gastight, refractory materials, as well as technical the ski products such as suspension rollers, the connecting elements of electrical appliances, the connecting elements of water and gas pipelines, connecting the elements of the brake system, casings, cables and belts.

For Shoe soles can be used, mainly in the presence of a binding agent (silicon dioxide/polymer), the composition of the polymer(s) based on, for example, natural rubber (NC), composition of polyisoprene rubber (IR), polybutadiene rubber (BK), butadiene-styrene copolymer rubbers (BSC), rubber-based copolymer of butadiene with Acrylonitrile (NSC).

For technical products can be used, for example, in the presence of a binding agent (silicon dioxide/polymer) polymer compositions on the basis of, for example, natural rubber (NC), composition of polyisoprene rubber (IR), polybutadiene rubber (BK), butadiene-styrene copolymer rubbers (BSC), polychloroprene, rubber-based copolymers of butadiene with Acrylonitrile (NSC), hydrogenated or carboxylating nitrile rubber copolymer of isobutylene-isoprene rubbers (IIC), halogenated Putilkovo rubber (in particular, brominated or chlorinated), copolymer of ethylene-propylene rubber (EPM), rubber-based ternary ethylene-propylene-diene copolymer (EPDM), chlorinated polyethylene, chloral Feofanova polyethylene, epichlorhydrine rubber, silicones, fluorocarbon rubber, polyacrylates.

The silica according to the invention or obtained by the process according to the invention can also be used as a catalyst carrier, adsorbent active substances (in particular, the carrier of liquids, for example, used in the food industry, such as vitamins (vitamin E), choline chloride), as a binder, textureimage agent or anti-commutes, as an element for battery separators, as an additive to toothpaste, paper.

The following examples explain the invention without limiting, however, its scope.

EXAMPLE 1

In the reactor of stainless steel with a volume of 25 liters enter 10 liters of purified water. The solution is brought to 80°C. All reactions occur at this temperature. With stirring (350 rpm, propeller stirrer) introducing sulfuric acid at a concentration of 80 g/l up until the pH becomes equal to 4.

Within 35 minutes in the reactor is injected simultaneously a solution of sodium silicate (weight ratio of SiO2/Na2O equal to 3.52)having a concentration of 230 g/l, with a rate of 76 g/min, and a sulfuric acid concentration of 80 g/l, with a feed rate that is installed so as to maintain the pH of the reaction medium at a value of 4. At the 30th minute of the addition the stirring speed was adjusted is about 450 rpm

After 35 minutes, adding the introduction of stop acid until the pH reaches a value equal to 9. Supply of silicate then also cease. Carry out ripening for 15 minutes at pH 9. At the end of maturation, the stirring speed was adjusted to 350 rpm

Then the pH was adjusted to pH 8 by the introduction of sulfuric acid. New simultaneous addition occurs within 40 minutes with a feed rate of sodium silicate, equal to 76 g/min (the same sodium silicate as when you first added together), and when the feeding speed of sulfuric acid having a concentration of 80 g/l is set so as to keep the pH of the reaction medium at the level of 8.

At the end of this simultaneous addition, the reaction medium is brought to pH 4 with sulfuric acid at a concentration equal to 80 g/l Medium maturing within 10 minutes at pH 4. 250 ml of flocculant FA 10 (polyoxyethylene with a molecular mass equal to 5·106g) at a concentration of 1% imposed on the 3-th moment of ripening.

The slurry is filtered and washed under vacuum (dry extract of 16.7%. After dilution (dry extract 13%) received the filter cake is crushed mechanically. The resulting paste is finely crushed using a turbine nozzle.

Characteristics of the obtained silicon dioxide P1 are as follows:

Specific surface area CTAB: 221 m2/g

Specific surface area by BET:240 m 2/g

V(d5-d50)/V(d5-d100): 0,74

Width Ld (XDC): 1,62

Width of pore distribution Idp: 1,42

Width L d (XDC): 1,27

The number of Sears×1000/specific surface area by BET: 42,9

Fashion XDC: 39 nm

Pore volume V80: 1,69 cm3/g

50S(after grinding ultrasound): 4,8 mcm

FDS: 4,6 ml

α: 0,00626 μm-1min-1

dw: 79 nm

L/IF: 0,62

EXAMPLE 2

In the reactor of stainless steel with a volume of 25 liters enter 9,575 kg of purified water and 522 g of sodium silicate (weight ratio of SiO2/Na2About equal 3,55)having a concentration of 235 g/l Solution is brought to 80°C. All reactions proceed at this temperature. Under stirring (300 rpm, propeller stirrer) introducing sulfuric acid at a concentration equal to 80 g/l, up until the pH reaches the value 4 (introduced 615 g of acid).

For 40 minutes in the reactor is injected simultaneously a solution of sodium silicate (weight ratio of SiO2/Na2About equal 3,55) at a concentration of 235 g/l with a feed rate of 50 g/min and sulfuric acid at a concentration of 80 g/l with a feed rate that is installed so as to maintain the pH of the reaction medium at a value of 4.

After 40 minutes, adding the introduction of acid stop as soon as the pH reaches a value equal to 9. Supply of silicate then also pregraduate 15-minute ripening at pH 9 and 80° C.

Then the pH within 2 minutes, adjusted to pH 8 by the introduction of sulfuric acid. New simultaneous addition carried out for 60 minutes with a feed rate of sodium silicate 76 g/min (the same sodium silicate as when you first added together) and the feed rate of sulfuric acid being in a concentration of 80 g/l, installed so as to maintain the pH of the reaction medium at a value of 8.

At the end of this simultaneous addition, the reaction medium is brought to pH 4 for 5 minutes using a sulfuric acid being in a concentration of 80 g/L. Then the environment is maturing for 10 minutes at pH 4.

The slurry is filtered and washed under vacuum (dry extract draught of 5.5%). After dilution (dry extract 12%) received the filter cake is crushed mechanically. The resulting paste is finely crushed using a turbine nozzle.

Characteristics of the obtained silica P2 are as follows:

Specific surface area CTAB: 182 m2/g

Specific surface area by BET: 197 m2/g

V(d5-d50)/V(d5-d100): 0,76

Width Ld (XDC): 1,12

Width of pore distribution Idp: 1,26

Width L d (XDC): 0,90

Fashion XDC: 57 nm

Pore volume V80: 1,40 cm3/g

50S(after grinding ultrasound): 4,1 mcm

FDS: 4,0 ml

EXAMPLE 3

In the reactor of stainless steel with a volume of 25 liters enter 10 liters of sodium silicate (the ri, the weight ratio of SiO 2/Na2About equal 3,55)having a concentration of 10 g/L. the Solution is brought to 80°C. All reactions take place at this temperature. Under stirring (300 rpm, propeller stirrer) introducing sulfuric acid at a concentration equal to 80 g/l, up until the pH reaches the value 4 (introduced 615 g of acid).

For 40 minutes in the reactor is injected simultaneously a solution of sodium silicate (weight ratio of SiO2/Na2About equal 3,55)having a concentration of 230 g/l, at 50 g/min and sulfuric acid in a concentration equal to 80 g/l, with a feed rate that is installed so as to maintain the pH of the reaction medium at a value of 4.

After 40 minutes, adding the introduction of acid stop upon reaching a pH of 8.

New simultaneous addition carried out for 60 minutes with a feed rate of sodium silicate 50 g/min (the same sodium silicate as when you first added together) and with a feed rate of sulfuric acid being in a concentration of 80 g/l, installed so as to maintain the pH of the reaction medium at a value of 8.

At the end of this simultaneous addition reaction medium is brought within 4 minutes to pH 4 with sulfuric acid at a concentration equal to 80 g/l Medium maturing within 10 minutes at pH 4.

The slurry is filtered and washed under vacuum (dry extract of sediment to 13.7%). After dilution (dry extract of 1.2%) of the precipitate on the filter is crushed mechanically. The resulting paste is finely crushed using a turbine nozzle.

Characteristics of silica P3 are as follows:

Specific surface area CTAB: 228 m2/g

Specific surface area by BET: 245 m2/g

V(d5-d50)/V(d5-d100): 0,76

Width Ld (XDC): 1,48

Width of pore distribution Idp: 1,98

Width L d (XDC): 1,16

Fashion XDC: 42 nm

Pore volume V80: 1,48 cm3/g

50S(after grinding ultrasound): 4,4 mcm

FDS: 4,3 ml

EXAMPLE 4

In the reactor of stainless steel with a volume of 25 liters enter 12 liters of sodium silicate solution (weight ratio of SiO2/Na2About equal to 3.5), having a concentration of 10 g/L. the Solution is brought to 80°C. All reactions take place at this temperature. Under stirring (300 rpm, propeller stirrer) introducing sulfuric acid at a concentration of 80 g/l, up until the pH reaches a value of 8.9.

Within 15 minutes, the reactor is injected simultaneously a solution of sodium silicate (weight ratio of SiO2/Na2About equal to 3.5), having a concentration of 230 g/l, with a rate of 76 g/min and sulfuric acid at a concentration of 80 g/l, with a feed rate that is installed so as to maintain the pH of the reaction medium at a value of 8.9. Thus obtained Sol loosely aggregated particles. Sol let drain and quickly cooled with a copper coil, which circulates holo is Naya water. The reactor quickly purify.

In a reactor with a volume of 25 liters enter 4 liters of purified water. Sulfuric acid at a concentration equal to 80 g/l, administered before until pH reaches the value 4. Within 40 minutes at a time add cold Sol with a feed rate of 195 g/min and sulfuric acid in a concentration equal to 80 g/l, with a feed rate, allowing you to set the pH at a value of 4. Spend 10 minutes maturation.

After 40 minutes, adding Zola/sulfuric acid for 20 minutes to conduct the simultaneous addition of sodium silicate with a feed rate of 76 g/min (the same sodium silicate as when you first added together) and sulfuric acid at a concentration of 80 g/l with a feed rate that is installed so as to maintain the pH of the reaction medium at a value of 4. After 20 minutes, the feed acid is terminated by receipt of pH 8.

New simultaneous addition occurs within 60 minutes with a feed rate of sodium silicate 76 g/min (the same sodium silicate as when you first added together) and the feed rate of sulfuric acid concentration equal to 80 g/l, installed so as to maintain the pH of the reaction medium at a value of 8. When the environment becomes very viscous, the mixing speed is increased.

At the end of this simultaneous addition reaction medium is brought within 5 minutes to pH 4 with sulfuric what Isletas in concentration, equal to 80 g/l Medium maturing within 10 minutes at pH 4.

The slurry is filtered and washed under vacuum (dry extract filtered sediment 15%). After diluting the obtained precipitate crushed mechanically. The resulting paste is finely crushed using a turbine nozzle.

Characteristics of silica P4 are as follows:

Specific surface area CTAB: 230 m2/g

Specific surface area by BET: 236 m2/g

V(d5-d50)/V(d5-d100): 0,73

Width Ld (XDC): 1,38

Width of pore distribution Idp: 0,67

Width L d (XDC): 1,14

Fashion XDC: 34 nm

Pore volume V80: 1,42 cm3/g

50S(after grinding ultrasound): 3,8 mcm

FDS: 4,6 ml

EXAMPLE 5

In the reactor of stainless steel with a volume of 25 liters enter 10 liters of sodium silicate solution (weight ratio of SiO2/Na2About equal 3,48)having a concentration of 5 g/L. the Solution is brought to 80°C. Under stirring (300 rpm, propeller stirrer) introducing sulfuric acid at a concentration of 80 g/l up until the pH reaches a value of 4.2.

Within 30 minutes the reactor is injected simultaneously a solution of sodium silicate (weight ratio of SiO2/Na2About equal 3,48)having a concentration of 230 g/l, with a feed rate of 75 g/min and sulfuric acid at a concentration of 80 g/l with a feed rate that is installed so as to maintain the pH of the reaction cf is built on the value of 4.2.

After 30 minutes, adding the introduction of acid stop as soon as the pH reaches a value equal to 9. Supply of silicate then also cease. Spend 15 minutes maturation at pH 9, all the while gradually increasing the temperature (within 15 minutes) with 80 to 90°C is the amount at which reaction takes place.

Then pH was adjusted to pH 8 by the introduction of sulfuric acid at a concentration equal to 80 g/L. New simultaneous addition is carried out in 50 minutes with a feed rate of sodium silicate 76 g/min (the same sodium silicate as when you first added together) and the feed rate of sulfuric acid at a concentration equal to 80 g/l, installed so as to maintain the pH of the reaction medium at a value of 8.

At the end of this simultaneous addition reaction medium is brought to pH 4 with sulfuric acid at a concentration equal to 80 g/l Medium maturing within 10 minutes at pH 4.

The slurry is filtered and washed under vacuum (dry extract of sediment 19,6%). After dilution (dry extract 10%) received the filter cake is crushed mechanically. The resulting paste is finely crushed using a turbine nozzle.

Characteristics of silica P5 are as follows:

Specific surface area CTAB: 135 m2/g

Specific surface area by BET: 144 m2/g

V(d5-d50)/V(d5-d100): 0,76

Width Ld (XDC): 1,52

The width of the distribution of the population then, Idp: 2,65

Width L d (XDC): 0,92

The number of Sears×1000/specific surface area by BET: 49,3

Fashion XDC: 57 nm

Pore volume V80: 1,12 cm3/g

50S(after grinding ultrasound): 5,9 mcm

dw: 159 nm

L/IF: 1,47

EXAMPLE 6

Prepare three polymeric composition:

- one containing precipitated vysokodispersnyi silicon dioxide Z1165MP, manufactured by Rhodia, a density of 2.1 g/cm3and the binding agent (reference composition R1),

two others, each containing silicon dioxide prepared according to example 4, and a binding agent (compositions C1 and C2).

Silicon dioxide Z1165MP has the following characteristics:

Specific surface area CTAB: 160 m2/g

Width Ld (XDC): 0,56

Width of pore distribution Idp: 0,50

Width L d (XDC): 0,56

Fashion XDC: 41 nm

Pore volume V80: 1,12 cm3/g

50S(after grinding ultrasound) <6 μm

α: 0,0049 μm-1min-1

dw: 59 nm

L/IF: 0,39

The results for the examples are given in table. 1-6.

100
Table 1

(The compositions, by weight)
Composition R1Composition C1Composition C2
BSK(1)100100
Silicon dioxide Z1165MP5000
Silicon dioxide of example 405050
The silane Si69(2)446,25
Diphenylguanidine1,451,451,45
Stearic acid1,11,11,1
Zinc oxide1,821,821,82
Antioxidant(3)1,451,451,45
Sulfenamid(4)1,31,31,3
Sulfur1,11,11,1
(1)Butadiene-styrene copolymer synthesized in solution (type Buna VSL 5525-0), not diluted oil

(2)The binding agent of the filler with the polymer (production company Degussa)

(3)N-(1,3-dimethyl-butyl)-N'-phenyl-p-phenylenediamine

(4)N-cyclohexyl-2-benzothiazolesulfenamide (CBS)

Composition C1 contains a certain amount of a binding agent, identical to the one that contains the reference composition R1. Composition C2 contains the number svyazivayuschego the agent, the corresponding specific surface area of the used silicon dioxide (example 4).

The composition is prepared thermomechanical processing of elastomers in an internal mixer (BRABENDER type) volume 75 cm3in two stages, with an average speed of blades 50 revolutions/minute, to obtain a temperature of 120°C, after these stages should the final stage of processing, carried out on the external mixer.

The temperature vulcanization choose 170°C. Conditions of vulcanization compositions correspond to the kinetics of vulcanization of the respective mixtures.

Properties of the compositions shown below, and measure (on vulcanized compositions) was carried out according to the following standards and/or methods:

The vulcanization properties (rheological properties)

(Original properties - rheometric when 170°C, t=30 minutes)

Standard NF T 43015

Use, in particular, to measure the minimum time (min) and maximum torque (Cmax) Monsanto rheometer 100 S.

Ts2 corresponds to the time during which it is possible to control the mixture; the mixture is hardened polymer, since Ts2 (the beginning of vulcanization).

T90 is the time at the end of which the vulcanization was 90%.

Mechanical properties (compositions, vulcanized at 170°C)

Stretching (modules): standard NF T 46002

The modules x (%), correspond to the voltage measured at the iformatsii stretch x (%).

Table 2
Composition R1Composition C1Composition C2
Vulcanization
Cmin (ln.lb)102114
Ts2 (min)3,12,13,1
T90 (min)29,442,036,4
Cmax (ln.lb)9197,5103
Mechanics
Module 10% (MPa)0,951,31,05
Modulus 100% (MPa)3,64,04,6
The module 200% (MPa)9,59,812,2

Note that the compositions C1 and C2, containing silicon dioxide according to the invention have a more advantageous properties compared with the properties of the reference composition R1.

Despite the suboptimal conditions of vulcanization, the composition of C1 leads to more pronounced hardening modules than the reference composition R1.

The regulation of the proportion of binding agent is carried out in the case of the composition C2, p is igodit to the kinetics of vulcanization, comparable to the kinetics in the case of the reference composition R1; moreover, the modules of the composition C2 (in particular, the modules 100% and 200%) is much higher than the modules obtained with the reference composition R1.

EXAMPLE 7

In the reactor of stainless steel with a volume of 25 liters enter 10 liters of sodium silicate solution (weight ratio of SiO2/Na2About equal 3,53)having a concentration of 5 g/L. the Solution is brought to 80°C. Under stirring (300 rpm, propeller stirrer) introducing sulfuric acid at a concentration equal to 80 g/l, up until the pH reaches a value of 4.2.

Within 35 minutes in the reactor is injected simultaneously a solution of sodium silicate (weight ratio of SiO2/Na2About equal 3,53 having a concentration of 230 g/l, with a feed rate of 50 g/min and sulfuric acid at a concentration of 80 g/l, with a feed rate that is installed so as to maintain the pH of the reaction medium at a value of 4.2.

After 35 minutes, adding the introduction of acid stop as soon as the pH reaches a value equal to 9. Then the flow of silicate also cease. Spend 15 minutes maturation at pH 9, all the while gradually increasing the temperature (within 15 minutes) with 80 to 90°C is the amount at which reaction takes place.

Then pH was adjusted to pH 8 by the introduction of sulfuric acid at a concentration equal to 80 g/L. New simultaneous addition occurs within 5 minutes with a feed rate of sodium silicate 50 g/min (the same sodium silicate, when first added together) and with a feed rate of sulfuric acid at a concentration equal to 80 g/l, installed so as to maintain the pH of the reaction medium at a value of 8.

At the end of this simultaneous addition reaction medium is brought to pH 4 with sulfuric acid at a concentration equal to 80 g/l Medium maturing within 10 minutes at pH 4.

The slurry is filtered and washed under vacuum (dry extract of sediment 16,8%). After dilution (dry extract 10%) received the filter cake is crushed mechanically. The resulting paste is finely crushed using a turbine nozzle.

Characteristics of silica P6 are as follows:

Specific surface area CTAB: 170 m2/g

Specific surface area by BET: 174 m2/g

V(d5-d50)/V(d5-d100): 0,78

Width Ld (XDC): 3,1

Width of pore distribution Idp: 1,42

Width L d (XDC): 2,27

The number of Sears×1000/specific surface area by BET: 50,6

Fashion XDC: 41 nm

Pore volume V80: 1,38 cm3/g

50S(after grinding ultrasound): a 4.3 µm

FDS: 3,7 ml

α: 0,00883 μm-1min-1

dw: 98 nm

L/IF: 0,78

EXAMPLE 8

In a reactor with a volume of 2000 litres injected 700 liters of process water. This solution is heated to 80°C by direct steam injection. Under stirring (95 rpm) introducing sulfur to the slot in concentration, equal to 80 g/l, up until the pH reaches a value of 4.

Within 35 minutes in the reactor is injected simultaneously a solution of sodium silicate (weight ratio of SiO2/Na2About equal to 3.52)having a concentration of 230 g/l, with a speed of 190 l/h and sulfuric acid in a concentration equal to 80 g/l, when the feed speed is set so as to maintain the pH of the reaction medium at a value of 4.

After 35 minutes, adding the introduction of acid stop as soon as the pH reaches a value equal to 8. Then spend new simultaneous addition of 40 minutes with a feed rate of sodium silicate 190 l/h (the same sodium silicate as when you first added together) and with a feed rate of sulfuric acid at a concentration equal to 80 g/l, installed so as to maintain the pH of the reaction medium at a value of 8.

At the end of this simultaneous addition reaction medium is brought to pH 5.2 with sulfuric acid at a concentration equal to 80 g/l Medium maturing within 5 minutes at pH 5.2.

The slurry is filtered and washed under filter press (dry extract of sediment 22%). The obtained filter cake is ground up, adding sodium aluminate in an amount corresponding weight ratio of Al/SiO20,3%. The resulting paste is finely crushed using a nozzle with a nozzle.

Characteristics of silica P7, poluchennogo is in the form of nearly spherical balls, these are:

Specific surface area CTAB: 200 m2/g

Specific surface area by BET: 222 m2/g

V(d5-d50)/V(d5-d100): 0,71

Width Ld (XDC): 1,0

Width of pore distribution Idp: 1,51

Width L d (XDC): 0,93

The number of Sears×1000/specific surface area by BET: 31,5

Fashion XDC: 34 nm

Pore volume V80: 1,44 cm3/g

Average particle size: >150 μm

50S(after grinding ultrasound): 4,8 mcm

FDS: 5,4 ml

50M(after grinding ultrasound): 5.0 µm

FDM: 11,5

α: 0,00566 μm-1min-1

dw: 68 nm

L/IF: 0,70

EXAMPLE 9

In a reactor with a volume of 2000 litres injected 700 liters of process water. This solution was adjusted to 78°C heating by direct steam injection. Under stirring (95 rpm) introducing sulfuric acid concentration equal to 80 g/l, up until the pH reaches a value of 4.

Within 35 minutes in the reactor is injected simultaneously a solution of sodium silicate (weight ratio of SiO2/Na2About equal to 3.52)having a concentration of 230 g/l, with a speed of 190 l/h and sulfuric acid in a concentration equal to 80 g/l, with a feed rate that is installed so as to maintain the pH of the reaction medium at a value of 4.

After 35 minutes, adding the introduction of acid stop as soon as the pH reaches the mn of the treatment, equal to 8. Then spend new simultaneous addition of 40 minutes with a feed rate of sodium silicate 190 l/h (the same sodium silicate as when you first added together) and with a feed rate of sulfuric acid concentration equal to 80 g/l, installed so as to maintain the pH of the reaction medium at a value of 8.

At the end of this simultaneous addition reaction medium is brought to pH 5.2 with sulfuric acid at a concentration equal to 80 g/l Medium maturing within 5 minutes at pH 5.2.

The slurry is filtered and washed on a vacuum filter (dry extract of sediment 18%). The obtained precipitate filtered mechanically crushed with technical water (add 10% water to the precipitate), adding sodium aluminate in an amount corresponding weight ratio of Al/SiO20,3%. The resulting paste is finely crushed using a turbine nozzle.

Characteristics of silica P8 are as follows:

Specific surface area CTAB: 194 m2/g

Specific surface area by BET: 212 m2/g

V(d5-d50)/V(d5-d100): 0,75

Width Ld (XDC): 1,11

Width of pore distribution Idp: 0,83

Width L d (XDC): 4,29

The number of Sears×1000/specific surface area by BET: 34,9

Fashion XDC: 47 nm

Pore volume V80: 1,37 cm3/g

50S(after grinding ultrasound): 5,9 mcm

α: 0,00396 μm-1min-1

EXAMPLE 10

Prepare two polymeric composition:

- one containing vysokodispersnyi precipitated silicon dioxide Z1165MP production company Rhodia (characteristics outlined in example 6) and a binding agent (reference composition R2)

- other, containing silicon dioxide prepared according to example 8, and a binding agent (composition C3).

Table 3

(Composition by weight)
The composition R2Composition C3
Bq(1)7070
BSK(2)1515
NBK(3)1515
Silicon dioxide Z1165MP500
Silicon dioxide according to example 8050
Silicon dioxide A1891(4)11
Paraffin oil(5)1010
Stearic acid1,51,5
Zinc oxide33
The glycol(6)33
TBBS(7)11
TBzTD(8)0,60,6
Sulfur1,51,5
(1)Polybutadiene (type Kosyn KBR01)

(2)Butadiene-styrene copolymer synthesized in solution (type Buna VSL 5025, not diluted oil)

(3)A copolymer of butadiene and Acrylonitrile (type Krynac 34-50)

(4)The binding agent of the filler with the polymer, γ-mercaptopropionylglycine (manufactured by Crompton)

(5)Plastol 352 (manufactured by Exxon)

(6)Type of PEG 4000 (production company)

(7)N-tert-butylbenzenesulfonamide

(8)the disulfide of tetrabenzylthiuram

Compositions prepared thermomechanical processing of elastomers in an internal mixer (BANBURY type) 1200 cm3. The initial temperature and rotor speed is set so as to achieve a temperature drop of the mixture close to 120°C. this step is the final processing on the external mixer at a temperature below 110°C. This phase provides an opportunity to introduce the system of cure.

The temperature of vulcanization is chosen equal to 160°C. Conditions of vulcanization compositions correspond to the kinetics of vulcanization of the respective mixtures.

Properties of the compositions are given below, while maintenance is conducted according to the following standards and/or methods:

The vulcanization properties (rheological properties)

(Original properties - rheometric at 160°C, t=30 minutes)

Standard NF T 43015

Use, in particular, to measure the minimum time (min) and maximum torque (Cmax) Monsanto rheometer 100 S.

Ts2 corresponds to the time during which it is possible to control the mixture; the mixture of polymer increase, since Ts2 (the beginning of vulcanization).

T90 is the time at the end of which the vulcanization was 90%.

Mechanical properties (compositions, vulcanized at 160°C)

- Elongation (modulus, tensile strength, elongation at break): standard NF T 46002

The modules x (%) correspond to the voltage measured at a tensile strain x (%).

- Tear resistance: standard NFT 46007 (method B).

- Hardness shore a ASTM D2240; the specified value is measured 15 seconds after application of power.

- Abrasion resistance: DIN 53516; measured value denotes the value of the loss on abrasion: the smaller, the better the abrasion resistance.

Table 4
The composition R2Composition C3
Vulcanization
Min (ln·lb)228
Ts2 (min)0,81,4
T90 (min)3,32,8
Cmax (ln·lb)9695
Mechanics
Module 10% (MPa)0,80,8
Modulus 100% (MPa)2,83,1
Modulus 300% (MPa)9,08,9
Tensile strength (MPa)11,912,8
Elongation at break (%)377418
Tear resistance (10 experiments) (kN/m)6873
Hardness shore A (points)6870
Abrasion loss (mm3)3629

It is established that the composition of C3 containing silicon dioxide according to the invention possesses a number of properties, especially interesting in comparison with the properties of the reference composition R2.

Having comparable with the reference composition R2 kinetics of vulcanization and modules similar to modules reference composition R2, composition C3 has a higher tensile strength, elongation, resistance to tear and shore hardness than the reference the song R2. And, especially, the composition C3 has a much higher durability than the reference composition R2: abrasion loss reduced by almost 20%.

EXAMPLE 11

Prepare three polymeric composition:

- one containing highly dispersed precipitated silica Z1165MP production company Rhodia (characteristics outlined in example 6) and a binding agent (reference composition R3),

two other containing silicon dioxide prepared in example 8, and a binding agent (composition C4), or silicon dioxide prepared in example 9, and a binding agent (composition C5).

Table 5

Formulations of the compositions, by weight
Composition R3Composition C4Composition C5
BSK(1)103103103
Bq(2)252525
Silicon dioxide Z1165MP8000
Silicon dioxide of example 80800
Silicon dioxide of example 90080
TESPT(3)6,48,07,7
Steer the new acid 2,02,02,0
Zinc oxide2,52,52,5
Antioxidant(4)1,91,91,9
DPG(5)1,51,81,8
CBS(6)2,02,02,0
Sulfur1,11,11,1
(1)Butadiene-styrene copolymer synthesized in solution (type Buna VSL 5025-1), diluted oil (37.5 wt.%)
(2)Polybutadiene (type Buna CB24, manufactured by Bayer)

(3)The agent bind the filler with the polymer, bis(3-(triethoxysilyl)propyl)tetrasulfide (produced by the company Degussa under the name Si69)

(4)N-1,3-dimethylbutyl-N-phenyl-para-phenylenediamine (Santoflex 6-PPD production company Flexsys)

(5)Diphenylguanidine (vulcanization accelerator D manufactured by Bayer)

(6)N-cyclohexyl-2-benzothiazolesulfenamide (Santocure production company Flexsys)

Each of the three compositions is prepared in three stages. The first two stages are carried out in an internal mixer, allowing thermomechanical processing at high temperature is round, until a temperature close to 150°C. these stages is the third stage of mechanical treatment on the cylinders at temperatures below 110°C. the third stage provides an opportunity to introduce the system of cure.

The mixer used in the first two stages, is an internal type mixer BRABENDER capacity of 70 cm3. The initial temperature and the speed of the rotors each time is set so as to achieve a temperature drop of the mixture close to 150°C.

The first step allows you to enter elastomers (at time t0), silicon dioxide (fractional introduction, 2/3, then 1/3) with a binding agent (at time t0+2 min), then with FGD (at time t0+4 min), and finally, stearic acid (t0+6 min). After discharge from the mixer (drop mixture, t0+7 min), then cooling the mixture (temperature below 100° (C) the re-introduction (at time t'0) in an internal mixer (and the temperature is then gradually increased) the second stage in the mixer allows thermomechanical processing to improve the dispersion of silica and the binding agent in the elastomeric matrix. At this stage, enter (at time t'0+1 min) zinc oxide and antioxidant.

After discharge from the mixer (the fall of the mixture at time t'0+4 min), then cooling the mixture (temperature below 100° (C) the third stud who I allow you to enter the vulcanization system (sulfur and CBS). It comes in a roll mixer, preheated to 50°C. the Duration of this stage is from 5 to 20 minutes.

After homogenization and passes through rollers each final mixture is rolled in the form of plates with thickness of 2-3 mm

The temperature of vulcanization is chosen equal to 160°C. Conditions of vulcanization compositions correspond to the kinetics of vulcanization of the respective mixtures.

Properties of the compositions are given below, and the measurements were carried out according to the standards and/or methods specified in example 10.

Dynamic properties (compositions, vulcanized at 160°C), such as tan Delta at 60°C, defined by viscoelastometer Metravib VA3000 in accordance with ASTM D5992, pre-charged 4%, at a frequency of 10 Hz (sinusoidal wave).

Table 6
Composition R3Composition C4Composition C5
Vulcanization
Min (Nam·m)253327
Ts2 (min)a 3.9the 3.84,1
T90 (min)14,216,315,2
Cmax (Nam·m) 717675
Mechanics
Module 10% (MPa)0,60,70,6
Modulus 100% (MPa)2,42,82,9
The module 200% (MPa)6,47,47,2
Hardness shore A (points)626767
Abrasion loss (mm3)725658
Dynamics
Tan Delta (60°C)0,1210,1130,100

Found that compositions C4 and C5, each containing silicon dioxide according to the invention have a combination of properties, especially interesting in comparison with the properties of the reference composition R3.

Having comparable with the reference composition R3 kinetics of vulcanization, the composition C4 and C5 have a higher modules and shore hardness than the reference composition R3. And, most importantly, composition C4 and C5 detect a much higher abrasion resistance than the reference composition R3: abrasion loss is reduced by approximately 20%. Finally, composition C4, and C5 have a smaller Tang is nsom Delta at 60° C than the reference composition R3, which is also particularly advantageous improves the properties of the final products on the basis of the compositions of C4 or C5.

1. A method of producing silicon dioxide, comprising the reaction of a silicate with an acidifying agent to obtain a suspension of silicon dioxide, then the separation and the drying of this suspension, characterized in that the reaction of the silicate with the acidifying agent is carried out according to the following successive stages:

(i) receive the aqueous basic solution having a pH from 2 to 5, preferably from 2.5 to 5,

(ii) to the specified base solution simultaneously adding silicate and acidifying agent so that the pH of the reaction medium was kept at 2 to 5, preferably from 2.5 to 5,

(iii) cease to add an acidifying agent, while continuing to introduce into the reaction environment silicate to obtain a pH of the reaction medium in the range of 7 to 10, preferably from 7.5 to 9.5,

(iv) to the reaction medium add both silicate and acidifying agent so that the pH of the reaction medium was maintained in the range of 7 to 10, preferably from 7.5 to 9.5,

(v) cease to add silicate, while continuing to introduce into the reaction environment acidifying agent to obtain a pH of the reaction medium below 6.

2. The method according to claim 1, wherein between step (iii) and step (iv) p is avodat the stage of ripening.

3. The method according to one of claims 1 and 2, characterized in that the stage of ripening is conducted at the end of step (v).

4. The method according to one of claims 1 and 2, characterized in that in step (v) cease to enter silicate, while continuing to introduce into the reaction environment acidifying agent to obtain a pH of the reaction medium in the range from 3 to 5.5, for example, from 3 to 5.

5. The method according to one of claims 1 and 2, characterized in that between step (iii) and step (iv) to the reaction medium add acidifying agent, and the pH of the reaction medium at the end of this add is from 7 to 9.5, preferably from 7.5 to 9.5.

6. The method according to one of claims 1 and 2, characterized in that all stages of the reaction of the silicate with the acidifying agent is carried out at a temperature of from 70 to 95°C, preferably from 75 to 90°C.

7. The method according to one of claims 1 and 2, characterized in that all stages of the reaction of the silicate with the acidifying agent is carried out at a constant temperature.

8. The method according to one of claims 1 and 2, characterized in that step (i) includes adding acidifying agent to the water to obtain pH values obtained basic solution from 2 to 5, preferably from 2.5 to 5, in particular from 3.0 to 4.5.

9. The method according to one of items 1 and 2, characterized in that step (i) includes adding acidifying agent to the mixture of water with silicate to obtain a pH of the base solution from 2 to 5, before occhialino from 2.5 to 5, in particular from 3.0 to 4.5.

10. The method according to one of claims 1 and 2, characterized in that step (i) includes adding acidifying agent to the base mud containing particles of silicon dioxide previously formed at pH above 7, to obtain a pH of the base solution from 2 to 5, preferably from 2.5 to 5, in particular from 3.0 to 4.5.

11. The method according to one of claims 1 and 2, characterized in that the drying is carried out by sputtering.

12. The method according to one of claims 1 and 2, characterized in that the compartment comprises filtering performed by the filter press.

13. The method according to one of claims 1 and 2, characterized in that the drying is carried out with the help of an atomizer.

14. The method according to one of claims 1 and 2, characterized in that the compartment comprises filtering carried out by using a vacuum filter.

15. The method according to one of claims 1 and 2, characterized in that the drying is carried out with the help of turbine nozzle.

16. Silicon dioxide, which can be obtained by the method according to one of claims 1 to 15.

17. Silicon dioxide, characterized in that it has a specific surface area CTAB (SCTAB) component is from 40 to 525 m2/g, specific surface area by BET (SBET)comprising from 45 to 550 m2/g, width Ld=((d84-d16)/d50) size distribution of particles measured by the grading of the XDC after grinding ultrasound, at least 0.91, and

the distribution is of pore volume, wherein the ratio of V(d5-d50)/V(d5-d100)well at least 0,66.

18. Silicon dioxide according to 17, characterized in that it has a width Ld of the distribution of particle sizes at least equal to 0.94.

19. Silicon dioxide on one of p and 18, characterized in that the ratio V(d5-d50)/V(d5-d100)well at least 0,68.

20. Silicon dioxide on one of p and 18, characterized in that it has a width Ld=((d84-d16)/d50) of the distribution of particle sizes measured by the grading of the XDC after grinding by ultrasound, is at least equal to 1.04 million, and

the distribution of the pore volume where V(d5-d50)/V(d5-d100)well at least 0,71.

21. Silicon dioxide on one of p and 18, characterized in that the average diameter (⊘50S) after grinding the ultrasound below 8.5 μm, in particular below 6.0 microns.

22. Silicon dioxide on one of p and 18, characterized in that the average diameter (⊘50Mafter grinding the ultrasound below 8.5 μm, in particular below 6.0 microns.

23. Silicon dioxide on one of p and 18, characterized in that it has a speed grinding, marked αmeasured according to the test, called the melting of the ultrasound in the pulse mode, at 100% power 600-watt transmitter at least equal 0,0035 μm-1min-1.

24. Silicon dioxide, Otley is audica fact, he has

specific surface area CTAB (SCTAB)constituting from 40 to 525 m2/g, specific surface area by BET (SBET)comprising from 45 to 550 m2/g, the width of pore distribution Idp greater than 0.70 and, in particular greater than 0,80.

25. Silicon dioxide at point 24, characterized in that it has a width Ld=((d84-d16)/d50) of the distribution of particle sizes measured by the grading of the XDC after grinding ultrasound, at least 0.91, in particular at least equal to 0.94.

26. Silicon dioxide on one of PP and 25, characterized in that the average diameter (⊘50Safter grinding the ultrasound below 8.5 μm, in particular below 6.0 microns.

27. Silicon dioxide on one of PP and 25, characterized in that the average diameter (⊘50Mafter grinding the ultrasound below 8.5 μm, in particular below 6.0 microns.

28. Silicon dioxide on one of PP and 25, characterized in that it has a speed grinding, marked αmeasured according to the test, called the melting of the ultrasound in the pulse mode, at 100% power 600-watt transmitter at least equal 0,0035 μm-1min-1.

29. Silicon dioxide, characterized in that it has a specific surface area CTAB (SCTAB)constituting from 40 to 525 m2/g, specific surface area by BET (SBET)comprising from 45 to 550 m2(d5-d50)/V(d5-d100)well at least 0,71.

30. Silicon dioxide on one of PP, 18 and 29, characterized in that the ratio V(d5-d50)/V(d5-d100)well at least 0,73, in particular at least equal to 0.74.

31. Silicon dioxide, characterized in that it has a specific surface area CTAB (SCTAB)constituting from 40 to 525 m2/g, specific surface area by BET (SBET)comprising from 45 to 550 m2/g, the width L d=((d84-d16)/d50) size distribution of particles less than 500 nm, measured by the grading of the XDC after grinding ultrasound, at least 0.90, in particular at least equal to 0.92, and the distribution of the pore volume where V(d5-d50)/V(d5-d100)well at least 0,74.

32. Silicon dioxide on one of p, 18, 29 and 31, characterized in that it has a width Ld of the distribution of particle sizes at least equal to 1.04 million, and the width L d distribution of particle sizes less than 500 nm, is at least equal to 0,95.

33. Silicon dioxide on one of p and 31, characterized in that the average diameter (⊘50Safter grinding the ultrasound below 8.5 μm, in particular the proceeds of 6.0 microns.

34. Silicon dioxide on one of p and 31, characterized in that the average diameter (⊘50Mafter grinding the ultrasound below 8.5 μm, in particular below 6.0 microns.

35. Silicon dioxide on one of p and 31, characterized in that it has a speed grinding, marked αmeasured according to the test, called the melting of the ultrasound in the pulse mode, at 100% power 600-watt transmitter at least equal 0,0035 μm-1min-1.

36. Silicon dioxide on one of p, 18, 24, 25, 29 and 31, characterized in that it has a ratio (the number of Sears×1000)/(specific surface area by BET (SBET)) below 60, preferably below 55.

37. Silicon dioxide on one of p, 18, 24, 25, 29 and 31, characterized in that it has such a particle size that fashion particle size distribution measured by the grading of the XDC after grinding ultrasound meets the following condition: fashion XDC (nm)≥(5320/SCTAB(m2/g))+8.

38. Silicon dioxide on one of p, 18, 24, 25, 29 and 31, characterized in that it has a pore volume (V80)formed by pores with a diameter of from 3.7 to 80 nm, at least about 1.35 cm3/year

39. Silicon dioxide on one of p, 18, 24, 25, 29 and 31, characterized in that it has a specific surface area CTAB (SCTAB)constituting from 60 to 330 m2/g, in particular from 80 to 290 m2/g, the specific surface is here on the BET (S BET)comprising from 70 to 350 m2/g, in particular from 90 to 320 m2/year

40. Silicon dioxide on one of p, 18, 24, 25, 29 and 31, characterized in that it has a specific surface area CTAB (SCTAB)comprising from 90 to 230 m2/g, in particular from 95 to 200 m2/year

41. Silicon dioxide on one of p, 18, 24, 25, 29 and 31, characterized in that it has a specific surface area by BET (SBET), component 110 to 270 m2/g, in particular from 115 to 250 m2/year

42. Silicon dioxide on one of p, 18, 24, 25, 29 and 31, characterized in that (SBET-SCTAB)≥5 m2/g, in particular ≥15 m2/year

43. Silicon dioxide on one of p, 18, 24, 25, 29 and 31, characterized in that (SBET-SCTAB)<50 m2/g, preferably <40 m2/year

44. Silicon dioxide on one of p, 18, 24, 25, 29 and 31, characterized in that it is almost spherical beads with an average size of at least 80 microns.

45. Silicon dioxide on one of p, 18, 24, 25, 29 and 31, characterized in that it is in powder form with an average size of at least 15 μm.

46. Silicon dioxide on one of p, 18, 24, 25, 29 and 31, characterized in that it is in the form of granules with a size of at least 1 mm.

47. The use of silicon dioxide, obtained by the method according to one of claims 1 to 15 or silicon dioxide on one of p-6, as reinforcing additives for polymers.

48. The use of silicon dioxide, obtained by the method according to one of claims 1 to 15 or silicon dioxide on one of PP-46, as a reinforcing additive in the composition of natural rubber.

49. The use of silicon dioxide, obtained by the method according to one of claims 1 to 15 or silicon dioxide on one of PP-46, as a reinforcing additive in the Shoe soles.

50. The use of silicon dioxide, obtained by the method according to one of claims 1 to 15 or silicon dioxide on one of PP-46, as reinforcing additives in polymer compositions for technical products.

51. The use of silicon dioxide, obtained by the method according to one of claims 1 to 15, or silicon dioxide on one of PP-46, as a catalyst carrier.

52. The use of silicon dioxide, obtained by the method according to one of claims 1 to 15, or silicon dioxide on one of PP-46, as absorbent active substances.

53. The use of silicon dioxide, obtained by the method according to one of claims 1 to 15, or silicon dioxide on one of PP-46, as binding agent.

54. The use of silicon dioxide, obtained by the method according to one of claims 1 to 15, or silicon dioxide on one of PP-46, as testudinoidea or protivokashleva agent.

55. The use of silicon dioxide, obtained by the method according to one of claims 1 to 15, or dio the sid of silicon on one of PP-46, as as for battery separators.

56. The use of silicon dioxide, obtained by the method according to one of claims 1 to 15, or silicon dioxide on one of PP-46, as an additive for toothpaste.

57. The use of silicon dioxide, obtained by the method according to one of claims 1 to 15, or silicon dioxide on one of PP-46, as an additive for paper.

58. The use of silicon dioxide in § 49 in the presence of tetrasulfide of monomethoxypolyethylene as a binding agent.



 

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3 ex

FIELD: organic chemistry, in particular blocked mercaptosilane cross-linking agents.

SUBSTANCE: claimed blocked cross-linking agent is obtained by reaction of 3-chloropropyltriethoxysilane and sodium 2-mercaptobenzothiazolate in isopropyl alcohol solution at 80-82°C. Mixture is agitated at this temperature for 15-20 h, cooled and alcohol is distilled followed by separation of finished product from sodium chloride. Cross-linking agent of present invention is useful in rubber mixtures based on non-polar polydienes with silicic acid and mineral fillers to simplify dispersion thereof in mixtures.

EFFECT: rubbers with decreased hysteresis.

1 tbl, 4 ex

FIELD: polymers, rubber composition, in particular rubber for footgear, textile, paper articles, etc.

SUBSTANCE: claimed method includes preparation of vulcanizable rubber mixture based on polar carbochain chloroprene or butadiene-nitrile rubber containing plasticizer in amount of 5-15 mass pts based on 100 mass pts of rubber. Plasticizer contains oxidized sunflower oil waste having iodine number of 90.75 mgI2/100 g; acid number 5.5 mgKOH/g; epoxy number of 1.4 % and molecular weight of 981.0 pretreated in air by ultraviolet light.

EFFECT: composition with increased freeze resistance.

2 tbl, 1 ex

FIELD: polymers, in particular diene rubber compositions reinforced with carbon white for production of pneumatic tire and intermediate therefor.

SUBSTANCE: sulfur-vulcanizing rubber composition for pneumatic tire production includes at least one diene elastomer (A component), carbon white as reinforcing filler (B component), binder of carbon white/elastomer having at least two functional groups, named as "X" and "Y" (C component), which may be grafted on the one side to carbon white via Y group, and on the other side to elastomer via X group, wherein X group represents α,β-unsaturated fatty acid ester having carbonyl group of general formula X 1 in γ-position. In formula R, R1 and R2 are monovalent hydrocarbon radical or R1 and R2 may be additionally hydrogen atoms. Also disclosed are pneumatic tire in raw and cured form, semimanufactured tire, in particular thread running surface from said rubber composition. Method for production of rubber composition, method for binding of carbon white with diene elastomer includes thermomechanical blending of A, B, and C components in one or more steps up to maximum temperature of 110-190°C.

EFFECT: rubber composition with improved hysteretic properties, high mechanical and technological characteristics; pneumatic tires and intermediates made of the same with low rolling resistance and increased endurance.

30 cl, 3 dwg, 6 tbl, 4 ex

Latex sealant // 2265038

FIELD: polymer materials.

SUBSTANCE: sealant destined to seal metallic packaging joints contains, wt %: synthetic latex with 48-55% solids 100, carboxymethylcellulose sodium salt 2.045, mixture of polyethylene ethers of mono- and dialkylphenols 1.11, disperser (sodium tripolyphosphane) 0.37, casein 0.185, oleic acid 0.37, foam suppressor 0.407, pigment filler 5,92, and water 60.125.

EFFECT: increased viscosity, improved homogeneity, enhanced adhesion, reduced drying time.

2 tbl

FIELD: polymer materials.

SUBSTANCE: invention relates to compositions containing (i) elastomer sensitive to oxidative, thermal, dynamic, or light- and/or ozone-induced degradation and (ii), as stabilizer, at least one compound belonging to type of S-substituted 4-(3-mercaptosulfinyl-2-hydroxypropylamino)diphenylamine, as well as to a method for preventing decoloration of substrates coming into contact with elastomers and to a method for stabilizing elastomers consisting in introducing into the latter or coating them with at least one compound belonging to type of S-substituted 4-(3-mercaptosulfinyl-2-hydroxypropylamino)diphenylamine. Composition of stabilized elastomer comprises (a) natural-origin or synthetic elastomer sensitive to degradation as mentioned above and (b) stabilizer, in particular at least one compound having following general formula 1: [R-S(=O)mCH2-CH(OH)-CH2]n-N(R1)2-n-R2 (1), where R represents C4-C20-alkyl, hydroxy-substituted C4-C20-alkyl, phenyl, benzyl, α-methylbenzyl, α,α-dimethykbenzyl, cyclohexyl, or -(CH2)qCOOR3, and, when m=0, R can be and, when n=1 and R4 is hydrogen, can also be R2-R1N-CH2-CH(OH)-CH2-S(=O)m(CH2)x- or R2-R1N-CH2-CH(OH)-CH2-S(=O)m-CH2-CH2-(O-CH2-CH2)y-; R1 represents hydrogen, cyclohexyl, or C3-C12-alkyl; R2 represents group ; R3 C1-C18-alkyl; R4 hydrogen or CH2-CH(OH)-CH2-S(=O)m-R; X C1-C8-alkyl; Y C1-C8-alkyl; m=0 or 1, n=1 or 2, q=1 or q=2-6, and y=1 or 2. Compounds of formula 1 stabilize elastomers, especially low-colored ones, prevent oxidative, thermal, dynamic, or light- and/or ozone-induced degradation thereof, and prevent decoloration of substrates coming into contact with elastomers.

EFFECT: enlarged assortment of elastomer-conditioning reagents.

16 cl, 3 tbl, 6 ex

Rubber mixture // 2255947

FIELD: rubber and tire industry.

SUBSTANCE: invention relates to rubber mixtures based on unsaturated rubbers and can be used in manufacturing protective rubbers. The rubber mixtures comprises oleic acid additionally in the mass ratio of stearic and oleic acids = 1:1.5, respectively, in the following ratio of components, mass. p. p.: unsaturated rubber, 100; sulfur, 1.7-2.2; rubber accelerator, 1.4-1.8; softening agent, 8.0-15.0; protective wax, 1.0-2.0; N-isopropyl-N'-phenyl-n-phenylenediamine, 1.0; polymerized 2,2,4-trimethyl-1,2-dihydroquinoline, 2.0; N-cyclohexylphthalimide, 0.2-0.3; technical carbon, 55.0-60.0; zinc oxide, 3.0-5.0; stearic acid, 0.8; oleic acid, 1.2. Invention provides expansion assortment of rubber mixtures eliciting the improved complex of technological and physical-mechanical properties: improved technological and some physical-mechanical properties of rubbers - increased wear resistance of rubbers, fatigue endurance and reduced cost of articles due to change of 60% of stearic acid for more cheap oleic acid.

EFFECT: improved properties of rubber mixtures and rubbers.

3 tbl

FIELD: rubber industry.

SUBSTANCE: invention relates to compositions containing crude emulsion rubber, synthetic latex, or natural rubber latex subjected to oxidative, thermal, dynamic, and/or light-induced degradation. In particular, invention provides composition, containing (i) crude emulsion rubber, synthetic latex, or degraded natural rubber latex, (ii), as stabilizer, at least one compound of formula I: (I), wherein R1 is C9-C20-alkyl, and (iii), as another stabilizer, at least one compound of formula II: (II), wherein R2 is C8-C12-alkyl; R3 is hydrogen, C8-C12-alkyl, cyclohexyl, 1-methylcyclohexyl, benzyl, α-methylbenzyl, α,α-dimethylbenzyl, or -CH2-S-R2; R4 is C1-C12-alkyl, benzyl, α-methylbenzyl, α,α-dimethylbenzyl, or -CH2-S-R2; and R5 is hydrogen or methyl. Invention also describes a method of stabilizing indicated mixture of compounds I and II.

EFFECT: enhanced efficiency of stabilizer composition as compared to each of stabilizers used separately.

16 cl, 3 tbl, 3 ex

FIELD: rubber industry.

SUBSTANCE: invention relates to compositions containing crude emulsion rubber, synthetic latex, or natural rubber latex subjected to oxidative, thermal, dynamic, and/or light-induced degradation. In particular, invention provides composition, containing (i) crude emulsion rubber, synthetic latex, or degraded natural rubber latex, (ii), as stabilizer, at least one compound of formula I: (I), wherein R1 is C9-C20-alkyl, and (iii), as another stabilizer, at least one compound of formula II: (II), wherein R2 is C8-C12-alkyl; R3 is hydrogen, C8-C12-alkyl, cyclohexyl, 1-methylcyclohexyl, benzyl, α-methylbenzyl, α,α-dimethylbenzyl, or -CH2-S-R2; R4 is C1-C12-alkyl, benzyl, α-methylbenzyl, α,α-dimethylbenzyl, or -CH2-S-R2; and R5 is hydrogen or methyl. Invention also describes a method of stabilizing indicated mixture of compounds I and II.

EFFECT: enhanced efficiency of stabilizer composition as compared to each of stabilizers used separately.

16 cl, 3 tbl, 3 ex

FIELD: rubber industry.

SUBSTANCE: plasticizer is prepared from alcohol production waste (65.79%), phthalic anhydride (32.89%) and tetrabutoxy titanate catalyst (1.32%), said alcohol production waste being, in particular, mixture of ethyl, isobutyl, and isoamyl alcohols resulted from preliminary distillation of ethanol production waste. Invention widens assortment of plasticizers, improves environmental conditions, diminishes consumption of hard-accessible and much more expensive ester plasticizer dibutyl phthalate, limits washing-out of plasticizer from vulcanizate based on polar caoutchoucs, and reduces swelling thereof.

EFFECT: improved performance characteristics of plasticizer and reduced expenses.

4 tbl, 3 ex

Polymer composition // 2266308

FIELD: polymer materials.

SUBSTANCE: invention relates to polymer composition designed for use in mining, mineral concentration, and chemical industries, which composition contains polyvinylchloride, vinyl chloride/vinyl acetate copolymer, epoxide 4,4'-isopropylidenediphenol resin, dicyanediamide, dioctyl phthalate, calcium stearate, talc, and rubber crumb.

EFFECT: increased resistance of lining made of thermosetting composition to hydroabrasive wear.

2 tbl

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