The polymer dispersion with high solid content (options), the composition of the sealing and sealing (options), a method of obtaining a dispersion of polymer particles with a high content of solids and dispersion of polymeric particles

 

(57) Abstract:

The method of polymerization predominantly of one or more acrylate and/or vinyl acetate monomers in the presence of latex results in dispersions of polymer particles with a high solids content with a lower viscosity than usual. A significant amount (wt.%) additional monomers may be present in large particles with non-spherical shape. Some of the original latex particles are stored during the polymerization, they increase the solids content and reduce the viscosity, located in the gaps between the large particles. The total solid content of the polymeric substances in polymers can easily be varied from 77 to 92 wt.% or more (technical task) that exceeds the content achieved in any previously published polymerization processes of the water. Viscosity at very high contents of solids determine pastorates, but the materials still remain stable during storage and further processing without separation of dispersion on agglomerated polymer part and released the water. The dispersion used for obtaining sealants, membranes, etc., as additives, and without Vysokoe solids content and thixotropy dispersion allow you to get the sealer is water-based with low shrinkage - the technical problem. 8 C. and 30 C.p. f-crystals, 8 tab., 1 Il.

The invention relates to free-radical polymerization of acrylate and/or vinyl acetate monomers in the latex, leading to the dispersion of polymer particles with a high content of solids (preferably more than 50 wt. %, preferably 7-95 wt.%). Monomeric composition, polymerized in the presence of latex should not be similar to the composition of the monomers used to produce latex, and can be used to modify the properties of the dried films obtained from the dispersion. High solids content makes the material budget for transportation or storage, and processing in the sealing material leads to the formation of the sealant with a low modulus, high elongation and low shrinkage.

Traditionally, sealants and sealing materials with high properties was obtained with the use of solvent-based polymer systems, such as silicone and polyurethane polymers as a binder for sealing compositions. These sealing compositions based solvents give the seals a good consumer properties (thixotropy and viscosity) and on the th of high quality material. However, in recent years due to enhanced state standardization and increased awareness of consumers to manufacturers of sealants based solvents is increased pressure to reduce VOC (the content of organic volatile compounds) in their product (e.g., VOC).

Dispersion of polymer particles in water is widely used in sealants, water-based, such as coatings and sealants. Their low viscosity, low emission of volatile organic compounds and ease of use were contributing factors to their application. However, regardless of the size of polymer particles existed barrier solids content of 40-65 wt.% (depending on the type of emulsifier and other conditions), above which it is difficult to prepare a dispersion of polymer particles. Therefore sealants with a high content of solids was obtained with the addition of fillers. Fillers dilute polymer in the final use, reducing compliance and improving the module. Polymer particles having a low value of Tg (glass transition temperature) (e.g., below 0oC) are commonly used in the compositions and sealant plotnicki the solids content is the European patent N 0515719 A1, which describes self-adhesive acrylate copolymer, which can be used for compositions that comprise self-adhesive surface layers. This acrylate copolymer receive a combined suspension and emulsion polymerization. The solids content, as described, is 30-70 wt.%, and according to the examples show 65 wt.% solid.

In the article Do lk Lee in The Jornal of Paint Technology, volume 42, No. 550 (1970), S. 579-587 discussed the location of the binary mixtures of spheres.

In U.S. patent 4130523 (Hoy and Peterson) revealed the solids content of about 70 wt.%. Their latex particles preferably have a diameter not greater than 1.5 μm.

The object of the present invention is the polymerization in the presence of pre-obtained latex of the additional monomers, forming a thixotropic product with high solids content, low viscosity, especially suitable for use in coatings and sealants.

Discovered that latex dispersion of latex polymer particles when used as a medium for further polymerization can lead to the formation of dispersions of polymer particles with a high content of solids (for example the show bimodal or multimodal distribution of particle size with particle diameters, in the range from about 0.05 to 100 μm. Received a wide distribution of particle size and good mixing during polymerization, it is believed, are the main factors to achieve high content of solids.

When removing the shear stress dispersion of polymer particles savusauna, but are capable of liquefaction. Large particles (greater than 4 microns), when formed, at the time of formation are typically non-spherical, preferably having an average aspect ratio between the largest and smallest diameters of each particle at least 1.5 times.

The drawing shows acrylate dispersion obtained similarly to examples 1-3 with increasing approximately H. Table VI presents the specific pH value and content in wt.% solid particles in the samples A-K. the Range of the distribution of particle size and variation of the shape of the particles is easily visible by microscopic examination under a microscope, in which a drop of polymer dispersions have between two object glasses.

Dispersions with a high solids content is produced by polymerization of monomers in the presence of latex (for example, using latex as the format of particles of average weight less than 2 μm) in the medium based on water. Latex is the primary source of smaller particles in the final dispersion of the particles. Latex is also environment water-based for the further polymerization.

A mixture of latexes are also used as source material, giving even greater flexibility of the composition and determining the properties of the final dispersion and films or seals, obtained from the dispersion. Such dispersions are usually thixotropic, especially when the solids content of more than 75 wt.%. Thixotropy promotes the use of polymer in applications such as sealants, when using a material with low viscosity at high shear. The material may have a high viscosity and thus impede (such as leakage) under conditions of low shear. Preferred polymers for the process and sealants contain polyacrylate, polyvinyl acetate and copolymers and combinations.

The monomers polymerized in the presence of latex, it is desirable to periodically add, for example, dosing them in latex or simultaneous dosing of latex and monomers. Preferably the monomers have a low solubility in water (e.g. less than 5 wt.% soluble in water), such that when Aeritalia. Large polymer particles, ultimately created during this polymerization, have a diameter of from about 2 to about 200 microns. The solids content in the dispersion of polymer particles is preferably at least 50, 60, 65, 75, 77 or 80 wt. %. The preferred range is from 70 to 95 percent by weight or 75 to 85, 88, 90 or 92 wt.% by weight of the dispersion.

Adding monomer in a pre-prepared latex can be carried out using any latex-based acrylate or vinyl acetate. The viscosity of the dispersion will typically be lower than that of such dispersions formed with other sequences of emulsion and suspension polymerization. When the original latex contains from 40 to 68% solids, the resulting dispersion of polymer particles may contain more than 70 wt.% or preferably from 75 to 92 wt.% solid.

Source latexes containing from 40 to 68 wt.% solids differ from latexes derived by conventional emulsion polymerization, because they are often bimodal or multimodal. This is due to the fact that a wide distribution of particle size or multimodal distributions are known to have pengendalian solids can be easily obtained by changing when the shearing force of the diameter of one or more fashion or by increasing or decreasing the number of particles with the same or different diameters. Technology is the creation of a broad or multimodal distributions described in the European patent N 0515719 A1 and U.S. patent N 4130523. Both publications are presented as preconditions of the invention and, therefore, included as a reference. Review article, entitled "Concentrated Colloidal Dispersions", Faraday Discussions of the Chemical Society, No. 76, published in the Royal Society of Chemistry, London 1983, incorporated by reference and describes various ways in the preparation of latexes with high solids content.

Commercially available latexes with high solids content, known as RhoplexTM2620 from Rohm and Haas, acrylate latex with a solids content of 62 wt.%, CarbobondTMXPD 2254 with a content of approximately 67 percent solids obtained from BFGoodrich Company, Breckville Ohio, used in examples 1-4; Acronal V 275TMBASF with the content of 65 wt.% the solids. Acronal V275TMdiffers from the other two latex content in the polymer few % of Acrylonitrile.

During the polymerization process in the presence of the latex was initially observed new small particles (less than 0.5 µm and sometimes less than 0,10 µm in diameter). At a certain solids content (depending the tion, the relative number of new small particles tends to decrease (probably due to agglomeration) and larger particles (diameter greater than 2 μm) are observed in large quantities. Obviously, the agglomeration of small particles into particles of large size is controlled manner without formation of coagulate (which you would expect in a typical polymer dispersions in water, when agglomeration). Although the above particles are often observed, the method of polymerization does not require their presence. In examples 1 and 2 larger particles have a diameter range of 2-4 μm, whereas in the subsequent examples in the modes of existence of particles with diameter from 2 to 4 and from 8 to 30 μm. Thus, examples 1 and 2 show a bimodal distribution, whereas examples 3 and 4 show a tri-modal distribution of particle diameters.

These polymer dispersions with a high solids content, particularly applicable as a sealant, especially type sealers water-based. The evaporation of water from traditional sealers water-based, low solids content during curing causes severe unwanted shrinkage. Shrinkage in the sealer water-based leads to residual pressures and stresses that can cause loss of UPSI compositions can reduce the maximum water loss and the maximum degree of shrinkage. When the sealing composition initially contains a polymer dispersion with a higher solids content in the final seal can be achieved even higher solids content by adding non-volatile fillers. As an alternative, sealant composition may be achieved by the same solids content with fewer fillers. This usually results in the sealing composition with high elongation, low modulus and high adhesion to the substrate. The viscosity of the sealant increases with the addition of solid particles to polymer dispersions with a low solids content. Adding large quantities of certain solid particles in the sealing composition of water-based significantly increases the module and reduces the limit strain at break of the composition containing sealing compound, when utverzhdenii, thus, reduces the operational properties of the sealing material.

The viscosity of these dispersions vary depending on the content of solids, but in General they are lower than the viscosity obtained when other types of water polymerizate. For a dispersion containing 75 or more wt.% solid washes is more desirable viscosity of less than 20,000 cps. When the solids content of 70-80 wt.% the desired viscosity of less than 10,000 cps under the same conditions of measurement.

The preferred monomers for latex and/or polymerization in the presence of latex are one or more alkylacrylate containing 4-16 or preferably 4-12 carbon atoms, such as ethyl-, butyl - and hexyl acrylate and/or vinyl acetate. Alkyl(alkyl)acrylates are included in the General term of alkylacrylate, although they tend to have higher glass transition temperatures. Preferably, when the polymer in each or both of the latex polymer particles, or a larger polymer particles have at least 50, 70, 75, 80, or 90 wt.% duplicate links of alkylacrylate or vinyl acetate, and preferably, it alkylacrylate. Such acrylates obtained by the esterification of one or more (alkyl)acrylic acids such as methacrylic acid, and one or more alilovic alcohols containing 1 to 12 carbon atoms. It is also preferable for the base polymer, as described above (e.g., at least 70, 80 or 90 wt.% thereof), that it is substantially non-crystalline polymer (e.g., elastomeric or manifesting itself as an elastomer at 20oC) the storage may have reversible strain of 200% or more and therefore are called elastomers.

Other monomers which may be used include Ethylenediamine monomers. They include monomers containing from 3 to 16 carbon atoms and optimally one or more heteroatoms O, N, Cl and/or F. They include conjugated diene (preferably 4-8 carbon atoms); and other monomers having a functional group of carboxylic acid, or a complex ester such as di-n-butylmalonate, acrylic acid, maleic anhydride, isobutylidene, Acrylonitrile, (alkyl)Acrylonitrile, acrylamide and their derivatives, alpha-methylsterol-styrene, vinyl chloride, vinylidenechloride, finalproject and other higher esters from the group of vinylacetate, containing from 4 to 30 carbon atoms. Multifunctional monomers capable of cross-linking, such as diacrylate or divinylbenzene, can also be used. Other monomers also include other functional groups of the acrylate containing from 4 to 16 carbon atoms, such as acrylates having a lateral double carbon-carbon links or side apostolica. These monomers can optimally be present in the latex is used as a polymerization medium. Preferably the presence of these mono is/or vinyl acetate).

It is desirable that the monomers used for the formation of larger particles comprised 10 wt.% or less, preferably 7 wt.% or less of monomers with high solubility (e.g., those whose solubility in water is 5 or 10 wt.% or more). Examples of monomers with limited high solubility include olefinic monobasic acid containing 3-10 carbon atoms, acrylic acid, olefin dibasic acid containing 4 to 12 carbon atoms and Acrylonitrile containing 3-10 carbon atoms.

The preferred environment for latex is water or mixtures, which contain a significant portion of water (for example, 70, 80, 90 or more wt.%). Solvents, such as alcohols, glycols, chlorinated alkali, etc. can be used in small quantities in the mixture.

The emulsifiers (a term that includes the surfactant used in the latex or latex polymerization, are commercial anionic emulsifiers, commonly used for emulsion polymerization, such as alkyl sulphonates or polysulphonate, olefin or polyaluminosilicate or polysulphonate, and carboxylates or polycarboxylate received the ionic emulsifiers, and also a mixture of anionic and nonionic emulsifiers. Polymeric emulsifiers obtained by the reaction or added separately, can also be used. It is preferable to use nonionic and cationic emulsifiers in smaller amounts, for example less than 50 wt.%, 30 wt.% or 10 wt.% from the total amount of emulsifiers at any time in the dispersion of polymer particles. Preferably, the emulsifiers were less than 10 wt.% and preferably less than 1 or 2 wt.% from the final dispersion of polymer particles.

Can be used any traditional agents transfer circuit used in emulsion, dispersion or suspension polymerization. These additives are designed to reduce the degree of branching of the polymer and its molecular weight to prevent the formation of macromolecular gel during polymerization.

Latex is used as a medium for the polymerization of the additional monomer, preferably has a pH from 1 to 11, more preferably from 3 to 9 and preferably from about 5 to 7. Preferably, the pH was created hydroxides of alkali metals selected from the group of Na, Ca, K and Li, or ammonia, or amines with up to 3 substituents, each of which contains the polymer particle size, forming the emulsion, and/or a larger polymer particles may be previously known initiators. The polymerization initiators can be any of the previously known initiators used in the process of free-radical polymerization in organic solvents in bulk or in aqueous environment, such as emulsion or suspension polymerization. Preferred initiators include soluble in oil azo or peroxy-terminaltory commonly used in polymerization processes in solutions in organic solvents, including but not limited to, 2,2'-azo-bis-isobutyronitrile, 2,2'-azo-bis-(2,4-dimethylvaleronitrile), 2,2'-azo-bis-(2-methylbutyronitrile), di(2-ethylhexyl)PEROXYDICARBONATE, tert-amyl-peroxyneodecanoate, exeloncorporationoo.htm. Water-soluble terminaltory, usually used in emulsion polymerization, including (but not limited to) ammonium persulfate, can also be successfully used. Redox initiators, including (but neogranichivatsya) tert-butyl hydroperoxide or cumonherface in combination with formaldehydefree sodium, or sodium bisulfite, or metabisulfite potassium, can also be successfully ispolzo with N,N-dimethylaluminum can also be successfully used.

Dispersion of polymer particles preferably contains two or more groups dispergirovannykh polymer particles, which leads to a wide distribution of particle size. One group consists of polymer particles with a mass-average diameter of from about 0.05 to 0.7 μm, or more preferably from 0.08 to 0.6 μm. Another group - preferably with mass-average diameter of from 0.7 to 4 μm and more preferably from 1.0 to 3.5 or 4 microns. Particles between 0.05 and 0.7 mcm and some particles with diameters between 0.7 and 4 μm originally derived from latex, and they are preferably present in an amount of from about 2 to about 20 wt.%, more preferably from about at least 10 to 20 wt.% of the total number of polymer particles. In the final dispersion of polymer particles, these particles derived from latex, will be present (possibly fewer) as one or more modes in the distribution of particle size. These fashion in the distribution of particle size is preferably present as having diameters of from 0.05 to 0.6 or 0.7 μm, and from 0.7 to 4 μm, and more preferably from 0.1 to 0.5 and from 1.0 to 3.5, and most preferably about 0.3 and 2.0 μm. Thus, at least one mode will be less than 1 μm and at least one mode will be greater than 1 μm.their particles (greater than 4 microns in diameter) are described below as non-spherical, the values of the diameters shown here are calculated in the measurement of particle size using dynamic light scattering. These particles will cause the mode of distribution of particle size is preferably from 4 to 100 μm and preferably from 6 to 40 μm. Each of these size ranges of particles will have a value of mass of particle size. It is desirable that the value of the mass of the particle size for large (greater than 4 μm) of the polymer particles was from 5 to 30 times greater than the value of the mass of the particle size small (4 μm or less) of the polymer particles. For polymer dispersions with a higher solids content, preferably at least 5, 10, 15, 60, or 70 wt.% polymer dispersions consisted of large particles having a diameter of not less than 4 μm, and more preferably between 4 and 100 microns. Preferably, at least 70, 80 or 90 wt.% or more particles in the dispersion was subject described the combined ranges of small and large size-specific.

Distribution of particle size found in polymer dispersions differ from normal distributions particle size created by emulsion or suspension polimerization. Specifically when Biy diameter greater than 1 μm and more preferably between 1 and 4 microns at high solids content, described above. The preferred multi-modal distribution is from 5 to 30 wt.% particles having diameters between 0.05 and 0.7 mcm, 20-70 wt.% particles having diameters of from 0.7 to 4 μm and 5-75 wt.%, and more preferably 30-75 wt.%, having particle diameters from 4 to 100 microns.

The diameters of the particles described herein, is determined by the light scattering method. They correlate well with measurements of the diffusion and sedimentation column chromatography and studies using the electron microscope. When referring to the average size, we mean preferably bulk sizes. Fashion in the distribution of particle size is used for determining the peak or maximum.

When fashion is defined as containing particles this means that fashion is a prevailing diameter, present in the peak of the distribution of particles by size.

The object of the invention to provide a stable dispersion of polymer particles by polymerization of unsaturated monomers in the pre-obtained latex. Incremental monomer are introduced, or in the fallopian mix in measured quantities or add portions within a certain period of time. While a significant part of the added monomachine add free-radical initiator within a certain period of time (for example, during the polymerization process) or you can choose the free-radical initiators that generate effective number of free radicals in the polymerization process. Preferably the addition of monomers during the period of time (as metered) from 1/2 to 24 hours, preferably from 1 to 10 hours and preferably from 1/2 to 6 hours it is also Desirable to choose such initiator and the temperature of polymerization in which the monomers are easily converted into polymer particles while adding monomers. Thus, the amount of unpolymerized monomers in the polymer dispersion and the reactor during the polymerization is minimized by periodic fractional or continuous addition of the monomer and the continuous polymerization of the monomers.

Some of the initial latex polymer particles may be lost due to agglomeration or coagulation during this process. However, a significant number of smaller latex particles, for example, 4 μm or less are retained during this process. The presence of at least two modes of greatly differing diameters species in the distribution of particle diameters in one dispersion of polymeric particles partially determines the achievement of soda is, obrazovanie in this process, have a non-spherical shape because of the way they are received. This leads to the average characteristic relation for particles with a size diameter of more than 4 μm, preferably greater than 1.5 and more preferably greater than 2. The average aspect ratio is the average for a group of particles, defined as the quotient of the largest diameter to the smallest diameter of each particle. These values are usually determined by examination of photographs of the particles, obtained using an electron microscope.

The latex used as the primary source of a polymerization medium, preferably is a latex obtained mainly from one or more alkylacrylate and/or vinyl acetate monomers. Other monomers previously described for use in the polymerization process, may also be present in the latex in the form of a polymer or copolymer in the latex. Preferably, the polymer latex contained at least 50, 70, 80, or 90 wt.% recurring units derived from alkylacrylate and/or vinyl acetate, and preferably from alkylacrylate containing from 4 to 16 carbon atoms. The latex preferably is anionic stabilized laaksovirta-active substances). Preferably, the polymer latex contained, at least to 0.05 wt.% repeating units of monomers of unsaturated one - or dibasic carboxylic acids, more preferably from 0.1 or 0.5 to 10 or up to 20 wt.%. The monomers of unsaturated carboxylic acids include those which contain up to 12 carbon atoms. Such monomers include acrylic acid, methacrylic acid, taconova acid, maleic acid, etc., Latex environment contains, preferably 20-70 wt. % solids and more preferably 50-68 wt.% the solids. The term solid is throughout the description to define components that do not evaporate easily during 1 h at 105oC.

It is desirable, but not necessary the presence of two or more stirring in the reactor. Most preferably, the stirrer was able to mix and homogenize the materials with high viscosity and high thixotropy, such as shown in the examples. Preferably a substantial shearing force to maintain the thixotropic material shifted liquefied (liquid) state. Non-spherical particles greater than 4 microns in diameter are typically formed at high solids content in terms of the appreciation the particles. Preferably, the stirrer was in close contact with the walls of the reactor and thoroughly mixed, the materials in the reactor. Desirable mixing blade anchor type.

Optimally no additional emulsifiers do not add together with additional monomers. Consider that some emulsifiers latex desorbers of small particles and adsorbed on the droplets of the monomer and the large polymer particles. It is established that a sufficient amount of emulsifier must be present to stabilize the particles in order to avoid catastrophic coagulation. Thus, if the latex is insufficient emulsifier, an additional emulsifier must be added during or after the addition of monomers or before adding the monomers.

The term "thixotropic" used to characterize the dispersion of polymer particles. Thixotropic dispersion is a dispersion, when the measured viscosity decreases with the factor from 5 to 1000, when the shear rate (rpm) was used to determine the viscosity viscometer is increased from 1 to 100 rpm, more preferably for this process, the change in the viscosity factor of 10 to 800 and predpociteniea polymerization for the polymerization of monomers in the latex is preferably from 20 or 40 to 110oC, more desirable from 50 to 100oC and preferable from 65 to 96oC.

The above dispersion can be used in the compositions of the seals with low shrinkage, especially in structures, water-based, does not contain low volatile or volatile organic compounds. The composition of the sealant may include inorganic fillers such as chalk, talc, titanium dioxide (in many forms such as white pigment, zinc oxide and kaolin clay. These fillers may be present in concentrations of up to 70 wt.% the solids. The composition of the sealant may include various plasticizers such as low molecular weight (for example, with an average molecular weight less than 10000, 20000 or 30000) polymers or oligomers that are compatible with one or more polymers polymer dispersion. They serve to soften the polymeric composition. The composition of the sealant may include biocides such as fungicides and anti musty agents), UV stabilizers, antioxidants, adhesion promoters, viscosity modifiers (which raise or lower the viscosity), cholesteremia agents and cross-linking agents. Preferably, at least 60, 70, 80, or 90 wt.% the solids composition of the seal performance is iesa at 105oC for 1 hour). It is desirable that the composition of the sealant was allocated less than 25 or 30, preferably less than 20 or 15 wt.% volatiles (organics and water), drying at 105oC for 1 hour. It is desirable that the seal had extrodinary ASTM D2452 at 20 psi with the mouthpiece of the extruder 2.64 mm less than 400 seconds at 25oC, more preferably from 10 to 400 seconds, and preferably from 20 to 100 or 200 seconds. The polymer dispersion may contain polymers with 2 or more different values of Tg. Low values of Tg desirable for flexibility at low temperatures, however, they can be sticky at elevated temperatures. When selecting suitable monomers for latex and polymerization of two or more phases in the seal can be polymers, divided into two or more phases, giving two values Tg and causing as flexibility at low temperatures and low stickiness in the same composition.

Examples 1-4 illustrate the preparation of polymer dispersions, containing 72, 79, 80 and 87% solids.

Get solution containing deionized water and concentrated hidrosis ammonium (29-30 wt.% NH3) in the ratio 50:50, and add it dropwise to karboksilirovannogo ATEX then placed in a reactor and stirred under a stream of nitrogen with an intensity of 100 rpm Under normal laboratory receipt as reactor using 4-liter reactor, equipped with a polymer jacket. For mixing use a low-speed mixer with a high torque electric rotating with the blades of the anchor type. For temperature regulation apply external heating/cooling bath, in which circulates a water-glycol mixture through the reactor with the polymer jacket. The latex is heated to 75oC for 1.5 h add a solution of laurylsarcosine, tert-anilinoquinazoline, ethyl acrylate and butyl acrylate. While adding support bath temperature in the range of 75-85oC. 15 minutes after the end of the add imposed tert-butylhydroperoxide (1,43 g) and begin cooling. Tert-butylhydroperoxide is the first half of the redox system used for reducing the amount of unreacted free monomers to an acceptable level. When the bath temperature reaches 50oC, add a solution containing 33.3 wt.% formaldehydeinduced sodium, deionized water and 33.3 wt.% anionic surfactants. Formaldehydeinduced sodium catalyzes tert-butylhydroperoxide, new monomers. The reaction mass is stirred for a further 1 hour at a temperature of more than 50oC. during this period of time the particles are captured (spent). Then the reaction mixture is cooled to room temperature and removed from the reactor. The resulting polymer is very thixotropic. The distribution of particle sizes is multimodal.

The original latex environment in examples 1-4 is carboxylesterase acrylic latex with a solids content of about 66 weight percent, a pH of about 2 and a viscosity of about 9576 NSEC/m2. This is a commercially available latex, The BFGoodrich Company trademark CarbobondTMXPD 2254.

In the continuous polymerization crust previously formed polymer is added to the reactor and heated to the appropriate reaction temperature under a layer of nitrogen. The monomer solution and the latex is then applied by the pump into the reactor at an appropriate speed and unreacted polymer is pumped from the bottom of the reactor with a velocity corresponding to the total speed of adding latex and monomer. This type of reaction schemes can be implemented at the facility CSTR (reactor with continuous stirring). The reactor piston flow can also be used (see table Brookfield No. DVIl), 28728 NSEC/m2at 100 rpm (23,9oC) and 215460 NSEC/m2at 1 rpm (23,9oC). The distribution of particle size of this dispersion was typically bimodal with one mode with center at 0.4 to 0.7 μm and another mod with center at 1 - 3 microns. Completely coagulated and dried films of this dispersion are characterized by two values of glass transition temperature is one at (-21) to (-23)oC and one at (-30) to (-31), characterizing various acrylate copolymers. The glass transition temperature were measured using a differential scanning colorimeter model Perkin Elmer DSC7 at the intensity of heating/cooling 10oC / minute (see table II).

The final dispersion has a viscosity, determined at cone-flat viscometer (Brookfield Model No. DVIl) 287280 NSEC/m2at 100 rpm (23,9oC) and 14364000 NSEC/m2at 1 rpm (23,9oC). Completely coagulated and dried film of the specified dispersion characterized by two values of glass transition temperature, as in example 1. The distribution of particle size in the specified dispersion was typically bimodal with one mode with center at 0.4 to 0.7 micron and other fashion center at 2 to 4 μm (see table III).

The final dispersion of the at 100 rpm (23,9oC) and more 4788000 NSEC/m2at 1 rpm (23,9oC). The polymer exhibits good stability during long-term storage. It easily forms a thin film. The distribution of particle size in the specified dispersion was typically a tri-modal with one fashion centre at 0.4 to 0.7 microns, another fashion centre at 2 to 4 microns and the third fashion centre at 8 to 30 μm. Completely coagulated and dried film of the specified dispersion are characterized by two different values of glass transition temperature, as in example 1 and 2.

Similar latex according to example 3 are prepared using the same procedure and recipe, but replace the original latex on RholexTM2620 (commercially available latex) from the company Rohm and Haas with a solids content of 62 wt. % with Monomeric composition, similar CarbobondTM. The resulting polymer dispersion has a solids content to 85.8 wt.% and the viscosity at pH 6 is similar to example 3.

Another similar latex according to example 3 was prepared using the same procedure and recipe, but replace the original latex on Acronal V275TMfrom BASF with a solids content of 65 wt.%, having Monomeric composition, similarly CarbobondTMplus a few wt.% acrilan example 3.

Example 4

An example of polymerization with the use only of butyl acrylate as a second incremental monomer shown in table IV. In the polymerization process using the same raw latex, as in examples 1, 2 and 3, and in addition, the same procedure as in examples 1, 2 and 3.

The final dispersion has a cone-flat viscosity (Brookfield Model No. DVIl) 292068 NSEC/m2at 100 rpm (23,9oC) and 3351600 NSEC/m2at 1 rpm (23,9oC). The distribution of particle size in the specified dispersion was typically a tri-modal with one fashion centre at 0.4 to 0.7 microns, another fashion centre at 2 to 4 microns and the third fashion centre at 8 to 30 μm. Completely coagulated and dried films of this dispersion shows two different values of glass transition temperature, one (-21) to (-23)oC, characterizing the initial latex, and more from the (-45) to (-53)oC characterizing polymethylacrylate. The values of glass transition temperature measured using a differential scanning colorimeter model Perkin Elmer DSC7 at the intensity of heating/cooling 10oC / minute. The dried film of the specified dispersion show the low-temperature plasticity characteristic of such material, as polymethylacrylate with meant is of such a polymer, as the original latex.

Example 5

An example of polymerization using the original vinyl acetate latex of the type illustrated in table V. the Method for producing this polymer identical to that used to obtain the original acrylic latex. The latex used in this example is commercially available ethylenevinylacetate latex, manufactured by Air Products, Inc., and has the trademark AirflexR500. This latex is characterized by a solids content of 55 wt.%, as is, a pH of 4.9 and a Tg value of the 5oC.

The final dispersion has a solids content was 82.3 wt.%. She has a viscosity, determined at cone-flat viscometer (Brookfield Model No. DVIl) less 957600 NSEC/m2at 50 rpm (23,9oC) and less 47880000 NSEC/m2at 1 rpm (23,9oC).

Example 6

The micrograph shows a series of wet polymer dispersions wet polymers obtained analogously to examples 1 to 4, which have between two object glasses for microscope. These polymers do not dilute. On these micrograph shows the range of the distribution of particle size and morphology, which can be achieved in the field of pH values and sadecky the composition of the sealant, containing a dispersion of polymer particles of this invention are presented in table VII.

Sealant receive, using a planetary mixer with a working capacity of about 3/4 gallon and capable of handling viscous, thixotropic materials, capable of vacuum mixing. Used mixer is characterized by different mixing speeds from 40 to 200 rpm Dispersion of polymer particles, fungicide and glycols add to mixer and mix until smooth, usually within 5 - 10 minutes. Then add mineral oil, epoxysilane and protivoplesnevye agent and mix until smooth. Then bring the pH of the mass with a mixture of concentrated ammonia/deionized water in a ratio of 50:50 to the desired final pH of the mass average of 6.5 to 8.0. Then mix the material under vacuum for 20 minutes to remove air from the sealant and pack the resulting material into briquettes.

Example 8

Some examples of U.S. patent 4130523 ('523) were reproduced in order to compare the viscosity values at different solids content in the product with the viscosity achieved by the method according to the invention. The obtained viscosity values are presented in table VIII.

Gaskets and sealants according to the invention can be introduced using a syringe or by extrusion or otherwise in different profiles using conventional equipment such as a gun or tube to seal. They can provide the desired values of volumetric shrinkage of about 5-30%, more preferably 8-20%.

These seals have a lower shrinkage, high elongation, low modulus, good adhesion to various substrates and quick drying with formation of slavocracy surface. They are not see oil compositions for coatings.

Although, in accordance with the Patent Law of the above is the best and preferred embodiments of the method and invention, but they but limit the invention, the scope of which is defined by the claims.

1. The polymer dispersion with high solid content, obtained by polymerization in the presence of a latex of acrylate monomers characterized by the distribution of polymer particle size of at least two modes, characterized in that it is an aqueous dispersion containing at least 77 wt.% discrete polymer particles obtained by polymerization of monomers containing at least 50 wt.% acrylate monomers with 4 to 16 carbon atoms and/or vinyl acetate, with one mode in the specified distribution of particle size has a particle diameter between 0.05 and 4 μm, and the other mode has particles of diameters between 4 and 100 microns and these particles with a diameter between 4 and 100 μm obtained by polymerization of the aforementioned acrylate or vinyl acetate monomers.

2. Dispersion under item 1, characterized in that the said discrete polymer particles are 77-92 wt.% from this dispersion, and the one this mod contains particles of size between 1,cteristics the ratio between the largest and the smallest diameter of each of the large particles is at least 1.5 times.

3. Dispersion under item 1, characterized in that the monomers contain at least 70 wt.% at least one acrylate monomer and/or vinyl acetate monomer and the above acrylate monomers have the General formula I

< / BR>
where R1Is h or methyl;

R2is alkyl containing 1 to 13 carbon atoms.

4. The variance in p. 2, characterized in that the above average aspect ratio is at least a 2.0.

5. Dispersion under item 1, characterized in that the polymer formed from the above-mentioned acrylate and vinyl acetate monomers and is mainly non-crystalline polymer with Dt, 0oOr less.

6. The polymer dispersion with high solid content, obtained by polymerization in the presence of a latex of acrylate monomers characterized by the distribution of polymer particle size of at least two modes, characterized in that it contains an aqueous dispersion containing at least 77 wt.% discrete polymer particles obtained by polymerization of monomers containing at least 50 wt.% at least one acrylate monomer from 4-16 carbon atoms and/or vinyl acetate, and hence ENISA least another mode has particles of diameters between 0.7 to to 100.0 μm, at least 20 wt.% particles have a diameter greater than 1 μm and such particles are formed by polymerization of the above acrylate and vinyl acetate monomers.

7. The variance in p. 6, characterized in that the particle diameter exceeding 1 μm are at least 35 wt.% of the total number of particles.

8. Dispersion under item 7, characterized in that the particle diameter exceeding 1 μm are at least 50 wt.% of the total number of particles.

9. Dispersion under item 7, characterized in that the monomers of the polymer particles comprise at least 70 wt.% from at least one acrylate monomer and/or at least one vinyl acetate monomer.

10. Dispersion under item 7, wherein at least 30 wt.% of the total number of particles comprise particles with a diameter between 1 and 4 microns.

11. The variance in p. 6, characterized in that it contains at least 80 wt.% discrete polymer particles.

12. The variance in p. 6, characterized in that inside the fashion with a particle size of between 0.7 and 100 µm specified distribution of particle size is characterized by the presence of at least one fashion between 0.7 and 4 microns and at least another fashion between 4 and 100 microns is re and at least 15 wt.% particles with a diameter of more than 4 μm.

13. Dispersion under item 12, characterized in that at least 35 wt.% particles have a diameter of more than 1 μm and at least 15 wt.% particles have a diameter of more than 4 μm.

14. Variance p. 13, wherein at least 50 wt.% the particles have a diameter greater than 1 μm and at least 25 wt.% particles have a diameter of more than 4 μm.

15. The variance in p. 6, characterized in that the said discrete polymer particles comprise at least 80 % by weight of the specified variance.

16. The variance in p. 6, characterized in that the dried film obtained from this dispersion, have at least two distinct values of glass transition temperature, varying in size from 2 to 100oWhen measured on a differential scanning colorimeter, with levels of temperature increase of 10 degrees/minutes

17. The variance in p. 6, characterized in that the polymer formed from the above-mentioned acrylate and vinyl acetate monomers and is mainly non-crystalline polymer with Dt, 0oOr less.

18. The polymer dispersion with high solid content, obtained by polymerization in the presence of latex unsaturated monomers, characterized rasr less than 1 μm, and in another fashion - greater than 1 μm, characterized in that it contains at least 77 wt.% discrete polymer particles, these unsaturated monomers contain at least 50 wt.% at least one acrylate monomer from 4-16 carbon atoms and/or vinyl acetate, the diameter of the particles in the same fashion is between 0.5 and 1 micron, and in another - more than 4 μm.

19. Dispersion under item 18, characterized in that the dried film obtained from this dispersion have at least two values of TD, measured on a differential scanning colorimeter when heating intensity is 10 degrees. /min, with at least two specified values Dt vary in size from 2 to 100oAnd one of these values TD is the characteristic of the dispersed polymer latex, and the other is characteristic of the discrete polymer particles formed of the added monomers.

20. Dispersion under item 18, characterized in that the polymer formed from the above-mentioned acrylate and vinyl acetate monomers and is mainly non-crystalline polymer with Dt, 0oOr less.

21. Polymer dispersion with high solid content, different polymerization of one or more unsaturated monomers in the latex water-based, moreover, these unsaturated monomers comprise at least 50 wt.% from at least one acrylate monomer from 4-16 carbon atoms and/or vinyl acetate, and these large particles have a diameter of more than 4 μm and the average aspect ratio between the largest and the smallest diameter of each particle of at least 1.5, and the residual polymer particles from the specified latex water-based, and these residual particles have a mass-average particle diameter less than 4 microns and are the product of polymerization of monomers, at least 50 wt.% these monomers used for obtaining the specified latex, represent one or more acrylate and/or vinyl ether monomers, and these large and the residual polymer particles comprise at least 77% by weight of the specified variance.

22. The variance in p. 21, characterized in that the polymer particles have a distribution of particle size, and the specified distribution of particle size is multimodal and is characterized by the presence of at least one fashion with a diameter of less than 3.5 microns and at least one fashion diameter greater than 4 microns.

23. The variance in p. 22, characterized those who by p. 23, characterized in that the large polymer particles contain at least 70 wt.% acrylate repeating units from at least one acrylate monomer of General formula

< / BR>
where R1Is h or methyl;

R2is alkyl containing 1 to 13 carbon atoms.

25. The variance in p. 21, characterized in that the latex water-based contains 0.1 to 10.0 wt.% unsaturated mono - or dicarboxylic acids by weight of the polymer latex and has a pH before polymerization 3-9.

26. The variance in p. 21, characterized in that the polymer formed from the above-mentioned acrylate and vinyl acetate monomers and is mainly non-crystalline polymer with Dt, 0oOr less.

27. The sealing composition and the sealant containing polymer dispersion, characterized in that it contains at least 77 wt.% polymer particles in a medium containing water, these polymer particles are distributed according to the size of the particles, with a particle diameter of 4.0 μm or more are non-spherical in shape and have an average aspect ratio between the largest and the smallest diameter of each particle equal to at least 1.5 times, and these particles dispersion code monomers and obtained by polymerization of the above acrylate and vinyl acetate monomers in the presence of latex.

28. The composition according to p. 27, wherein the polymer particles comprise at least 80 % by weight of the specified polymer dispersion, and the particle diameter of at least about 4.0 μm represent at least 30 wt.% the specified polymer dispersion, with the specified dispersion comprises at least 10 wt.% particles that have a diameter less than 4 microns.

29. The composition according to p. 28, characterized in that it has extraterrest by the ASTM D2452 when 13,79 kPa with the mouthpiece of the extruder 2.64 mm with less than 400 at 25oC.

30. The composition according to p. 29, characterized in that the said polymer particles contain at least 70 wt.% acrylate repeating units of the acrylate monomers of General formula

< / BR>
where R1Is h or methyl;

R2is alkyl containing 1 to 13 carbon atoms.

31. A method of obtaining a dispersion of polymer particles with a high content of solids, characterized in that the latex containing polymer particles, which have at least 50 wt.% recurring units of at least one acrylate and/or vinyl acetate monomer, and add polymerizing monomers polymerized by the method of free radical polymerization and containing p is their non-spherical particles with a mass-average particle diameters of at least 4 μm, having an average aspect ratio between the largest and the smallest diameter of each particle equal to at least 1.5 times, by dispersion with a solids content of at least 77 wt.%.

32. The method according to p. 31, characterized in. that said dispersion of polymer particles of a specified latex and these large non-spherical particles are characterized by a distribution of particle size, the specified distribution of particle size is multimodal and having at least one fashion diameter less than or equal to 4 μm and at least one fashion, which has a diameter greater than 4 μm, and the above particle diameter of more than 4 μm are at least 30 wt.% particles in the specified distribution of particle size and these particles with a diameter less than 4 microns comprise at least 10 wt.% particles in the specified distribution of particles by size.

33. The method according to p. 32, characterized in that it is carried out in the mixer for materials with a dynamic viscosity, defined taper-flat type viscometer, at 25oAnd about 20./min at least 10000-70000 mPas.

34. Dispersion of polymer particles, characterized in that it contains the water dispersion of the ore one acrylate and/or vinyl acetate monomer, moreover, these water dispersion have a viscosity of less than 30,000 mPas at the 24oAnd about 20./min, measured at cone-flat viscometer, and these particles are obtained by polymerization of the above acrylate and vinyl acetate monomers in the presence of latex.

35. The variance in p. 34, wherein the specified subjected to polymerization monomers containing at least 50 wt.% alkylacrylate, in which the alkyl contains from 1 to 12 carbon atoms.

36. The composition of the sealing and sealing, characterized in that it contains an aqueous dispersion having at least 77 wt.% discrete polymer particles obtained by polymerization of monomers containing at least 50 wt.% at least one acrylate monomer containing 4-16 carbon atoms and/or vinyl acetate monomer, and this dispersion has a distribution of particle size, which is characterized by at least one mode in the distribution of particle size between 0.05 and 0.7 mcm and at least another fashion between 0,7 and 100.0 μm, and a specific distribution of particle size of at least 20 wt.% particles have a diameter greater than 1 μm, and these particles are obtained by polymerization of the above acrylate and VCAM in itself protivoplesnevye agent or a fungicide and Packed in cartridges.

38. The composition according to p. 36, characterized in that this fashion in the distribution of particle size between 0,7 and 100.0 μm includes at least one fashion diameter between 0.7 and 4 microns, and at least one fashion with a diameter of between 4 and 100 μm and contains at least 20 wt.% particles of diameter greater than 1 μm and 15 wt.% particles with a diameter of more than 4 μm.

 

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