Process of producing foamed vinylaromatic polymers

FIELD: polymer production.

SUBSTANCE: process comprises: polymerization in aqueous suspension of at least one vinylaromatic monomer in presence of suspending agent selected from phosphoric acid salts; discharging foamed granules from reaction vessel; washing thus obtained granules with aqueous solution containing 0.005-2% by weight nonionic surfactant; separating washed granules, whose surface contains no inorganic phosphoric acid salts; and drying these granules in air flow.

EFFECT: achieved lack of foam in effluent after washing of polymer being foamed.

8 cl, 1 tbl, 4 ex

 

The present invention relates to a method for producing expanded onto vinylaromatic polymers.

More specifically, the present invention relates to a method for producing expanded onto polystyrene.

Vinylaromatic polymers, and among them, in particular, polystyrene, are known products, which already for a long time are used for the manufacture of compact and/or expanded onto products, which are used in various application sectors, among which the most important are the manufacturer of household appliances, engineering and construction industry, office equipment, etc. of Particular interest is the use in insulation, where vinylaromatic polymers are mainly used in foamed form.

Such foamed products obtained by the swelling of the granules are expanded onto a polymer pre-impregnated with a blowing agent, in a pre-expander and by forming the swollen particles in a closed form by simultaneous influence of pressure and temperature. The swelling of the particles mainly occurs under the action of water vapor or other gas that is supported at a temperature slightly above the glass transition temperature (Tg) of the polymer.

In the production of expanded onto products such processing, ka is rinsing and drying after polymerization, used to remove chemicals, possibly remaining on the surface of the particles. In particular, expanded onto the granules obtained with the aid of a process carried out in aqueous suspension, at the end of the polymerization can be processed to remove a suspending agent, which "pollutes" the surface of the particles, causing certain disadvantages. Indeed, the presence of a suspending agent leads to a prolonged drying time and reduces the performance of the technology (for example, limits the adhesion of the molded) in the manufacture of foamed products.

Drying, which usually produce warm air, requires a long time, because, in order to avoid losses of blowing agent, it is necessary to perform at low temperatures, below 40°C.

In U.S. patent 5041465 polymerization particles is carried out in the presence of finely dispersed calcium phosphate (TPA), used as a suspending agent; removing TFA carried out by washing the product with acidic substances, in particular hydrochloric acid.

In U.S. patent 4793406 remove inorganic suspending agent is also carried out using strong acids.

In U.S. patent 4286069 also described the method of preparation of the aqueous suspension expanded onto granules of styrene polymers in which, if suspendium Agay the fact is inorganic salt of phosphoric acid, for example, calcium phosphate, the granules obtained after the polymerization, washed with nitric acid.

In these cases, the duration of drying is small, however, the use of strong acids creates serious problems of ensuring the safety of employees and facilities, which significantly increases the cost of manufacturing expanded onto the granules.

To overcome the disadvantages associated with processing/washing acids, has been proposed an organic suspendida agents. For example, in U.S. patent 4560705 did not use inorganic suspendida agents, avoiding, thus, the use of acids for cleaning particles. This drying is short, but suspendisse agent, such as dodecylbenzenesulfonate sodium, does not require stage of leaching, it produces foaming in wastewater.

The presence of foam in wastewater leads to the construction of a separate centrifuges or creates serious problems in biological settings, because the foam can carry out active sludge, necessary for the decomposition of organic residues.

The disadvantages of both ways of processing are expanded onto granules obvious. In the first case, processing acids requires technological costs that affect the cost of production; in the second case precuts is of foam complicates any conventional wastewater treatment in biological systems.

To date, the applicant discovered a system that guarantees quick drying expanded onto granules vinylaromatic polymers obtained in aqueous suspension in the presence of inorganic salts of phosphoric acid, for example tricalcium phosphate or magnesium phosphate, but lacking known in the art and the above deficiencies. Such salts can be added to the polymerization mixture either in thin-dispersed form, or can be synthesized in situ no reaction between sodium pyrophosphate and magnesium sulfate.

Thus, the present invention is a method of obtaining expanded onto vinylaromatic polymers, which includes:

a) polymerization in aqueous suspension of at least one vinylaromatic monomer in the presence of a suspending agent selected from inorganic salts of phosphoric acid;

b) removing the expanded onto granules of the reaction vessel,

c) washing the obtained in this way granules with an aqueous solution containing 0.005-2% of the mass. non-ionic surface-active agent;

d) removing the washed granules on the surface which essentially does not contain any inorganic salts of phosphoric acid, and drying of these granules in air flow.

In accordance with the present invention the polymerization vinylaromatic is one monomer in aqueous suspension is carried out in certain conditions and in the presence along with suspensorium agent, additives, well known in this technical field. For example, the polymerization can be carried out in the presence of an initiating system and a blowing system. The initiating system includes two peroxide, one with a half-life equal to one hour at 85-95°and the other with a half-life equal to one hour at 110-120°C.

Together with vinylaromatic polymers, which is the object of the present invention may be used in any foaming agent, which may be enclosed in a polymer matrix. Usually use liquid substances with boiling points in the range from 10 to 100°C, preferably from 20 to 80°C. Typical examples are aliphatic hydrocarbons, freon, carbon dioxide, water, etc.

Foaming agent may be added to the polymer during the operation of polymerization or, alternatively, by impregnation of the granules obtained after the polymerization, or by injection box it into the molten product. After adding receive the polymer in the form of granules, which can be converted into foamed articles having a density in the range from 5 to 50 g/l, preferably from 8 to 25 g/l, as well as having excellent thermal insulation properties. To increase the retention of a blowing agent in the polymeric matrix, Nar is do with a blowing agent, you can use additives that can form as a weak (for example, hydrogen bridges)and strong ties (e.g., acid-base adducts). Examples of such additives are methyl alcohol, isopropyl alcohol, dioctylphthalate, dimethylcarbonate, compounds containing the amino group. These additives are usually added during the polymerization and/or injected into the polymer with a blowing agent.

Adding foaming agents are preferably produced during the polymerization; they are chosen from aliphatic or cycloaliphatic hydrocarbons containing from 3 to 6 carbon atoms, such as n-pentane, isopentane, cyclopentane, or mixtures thereof; halogenated derivatives of aliphatic hydrocarbons containing from 1 to 3 carbon atoms, such as, for example, DICHLORODIFLUOROMETHANE, 1,2,2-trifluoroethane, 1,1,2-trifluoroethane; carbon dioxide and water.

The term "vinylaromatic monomer used in the present description and the claims, essentially refers to the product corresponding to the following General formula:

where n is zero or an integer from 1 to 5, R is a hydrogen atom or methyl, a Y is halogen, such as chlorine or bromine, or alkyl or CNS radical containing from 1 to 4 carbon atoms.

Examples vinylaromatic monomers described above is the General formula, are styrene, α-methylsterol, methylsterol, atillery, butalbiral, dimethylstyrene, mono-, di-, tri-, Tetra - and pentachlorophenol, Postira, mitoxantron, acetoxystyrene etc. Preferred vinylaromatic monomers are styrene and α-methylsterol.

Vinylaromatic monomers having General formula (I), can be used individually or in mixtures up to 50% of the mass. with other copolymerizable monomers. Examples of such monomers are (meth)acrylic acid, With1-C4-alkalemia esters of (meth)acrylic acid such as methyl acrylate, methyl methacrylate, acrylate, methacrylate, isopropylacetate, butyl acrylate, amides and NITRILES of (meth)acrylic acids such as acrylamide, methacrylamide, Acrylonitrile, Methacrylonitrile, butadiene, ethylene, divinylbenzene, maleic anhydride, etc. Preferred copolymerizable monomers are Acrylonitrile and methyl methacrylate.

Get vinylaromatic polymer or copolymer has a molecular weight Mw in the range of 50,000 to 250,000, preferably from 70,000 to 200000. In General, a more detailed description of the method of preparation of expanded onto vinylaromatic polymers in aqueous solution or, more generally, the polymerization in suspension can be found in the Journal of Macromolecular Science, Review in Macromolecular Chemistry and Physics c31 (263) 215-299 (1991) or in international Pat the things the application WO 98/51734.

It expanded onto vinylaromatic polymers obtained by the method which is the object of the present invention, may be added conventional additives commonly used in commercial materials, such as pigments, stabilizers, plantamajoside agents, mineral fillers metaloprokatnyj (athermal) materials, antistatic agents, leavening agents, substances imparting vibration strength, etc. In particular, during the polymerization, it is preferable to add mineral fillers of metaloprokatnyj (athermal) materials, such as graphite, or reflective materials, such as titanium dioxide, in quantities whose values are in the range of from 0.05 to 25 wt%. calculated on the total weight of the obtained polymer.

Upon completion of the polymerization get essentially spherical polymer beads, the average diameter of which lies in the range from 0.2 to 2 mm, inside which are evenly distributed foaming agent.

To increase the stability of the suspension, the viscosity of the reagent solution can be increased by dissolving in it vinylaromatic polymer at concentrations of from 1 to 30 wt. -%, preferably from 5 to 20% based on the weight of monomer. The solution can be obtained either by dissolving the pre-obtained polymer (for example, fresh polymer or waste is radiusa polymerization and/or expansion) in a mixture of reagents, or pre-polymerization of the monomer or mixture of monomers in mass to provide the above concentrations and the subsequent continuation of the polymerization in aqueous suspension in the presence of other additives.

Upon completion of the polymerization granules discharged from the polymerization reactor and washed with a continuous or periodic manner with a solution containing a surface-active agent. Non-ionic surface-active agent (nonionic surfactants) are selected from alcohols/S8-C18ethoxylated and/or propoxycarbonyl fatty acids (Empilan KCL, COAG from Huntsmann), ethoxylated and/or propoxycarbonyl ethers of glycerol, the values of the average molecular weight Mw of which are in the range from 3500 to 5000 (Voranol 4555 from Dow), glycols, condensed with ethylene oxide (EO) and/or propylene oxide (PO), ethoxylated and/or propoxycarbonyl nonylphenols containing 0-5 parts of ethylene oxide and/or propylene oxide (Empilan NP from Huntsmann), ethoxylated and/or propoxyethanol sorbitol containing 5-20 parts of ethylene oxide and/or propylene oxide (for example, Armotan PN020 from ICI), potassium salts of fatty acids of coconut oil, methylethylamine (Nansa from Huntsmann).

The main types of such surface-active agents described in "Dispersing Powders in Liquids", Ralph D. Nelson Jr., Ed. Elsevier, 1988.

Flushing usually occurs at a temperature in the range from 20 on the 50° In vessels with stirring, containing surface-active agent in concentrations that are within the range of 0.01 to 2 wt. -%, preferably from 0.02 to 1%.

Upon completion of the polymerization and washing the surface-active agent obtained granules are pre preparation is usually applied to traditional materials and which essentially consists of:

1) coating the granules with a liquid antistatic agent such as amines, tertiary ethoxylated alkylamines followed the, copolymers of ethylene oxide and propylene oxide, etc. the Purpose of this process is to enhance the adhesion of the coating and sieving of the particles prepared in suspension;

2) drawing on these pellets coating essentially consisting of a mixture of mono-, di - and tri-ethers of glycerol or other alcohols with fatty acids and metallic stearates such as zinc stearate and/or magnesium stearate.

For a better understanding of the present invention and its execution below are some illustrating, but not limiting examples.

Comparative example 1

A 2-liter reactor equipped with a stirrer, was loaded with 100 parts of styrene monomer, 0.30 parts of benzoyl peroxide, 0.15 parts of tertbutylbenzene, 100 parts of demineralized water, 0.2 parts of tricalcium phosphate and 20 parts per million of dodecylbenzenesulfonate sodium.

Then the mixture was heated to 90° With at least 4 hours and up to 125°C for another 6 hours.

During the rise of temperature from 90 to 125°was added foaming agent (7 parts of n-pentane).

Upon completion of the polymerization pellets were separated by centrifugation, and then washed equal part of demineralized water.

Then the pellets were separated by centrifugation and placed in a column with a diameter of 10 cm and a height of 80 cm for drying air at 23°With (flow rate of 3000 l/h). Required for drying time was 40 minutes.

To the thus obtained granules are expanded onto a polymer was added to 0.02% ethoxylated amine; then the granules were sieved, separating a fraction with a diameter of from 1 to 1.5 mm.

Then to this faction gained 0.25% glycerylmonostearate and 0.05% of magnesium stearate.

The product was subjected to preliminary foaming by means of water vapor at a temperature of 100°and density of 15 g/l, and then endured during the day.

Foamed granules used the next day for molding blocks (size 1040×1030×550 mm) under a pressure of 0.5 bar (50 kPa), measuring the duration of cooling (which was equal to 12 minutes).

Then the blocks were cut into flat sheets, for which measured the sintering, which was equal to 15%.

In the bottle of capacity of 200 g was placed 50 g of the mother liquor after polymerization and washing and mixed in the tip is in the minutes, assessing the presence of foam. Observed the formation of foam height of 1 cm, which completely disappeared after settling for 10 minutes.

Comparative example 2

Granules, polymerized in accordance with comparative example 1 were separated by centrifugation, and then washed with an equal amount of demineralized water containing 0.05% dodecylbenzenesulfonate sodium (NaDDB).

The granules were then separated by centrifugation and placed in a column with a diameter of 10 cm and a height of 80 cm for drying air at 23°With (flow rate of 3000 l/h). The time required for drying was 11 minutes.

To the thus obtained pellets was added, and the additive granules are sieved, wspanialy to 15 g/l, was formed in accordance with the procedure adopted in comparative example 1.

It was found that the duration of cooling was 11 minutes, and sintering was 50%.

In the bottle of capacity of 200 g was placed 50 g of the mother liquor after polymerization and washing, and was stirred for minutes, checking for the presence of foam. Observed the formation of stable foam height of 10 cm After 10 minutes, the height of the foam was still 6 see

Example 1

Granules, polymerized in accordance with comparative example 1 were separated by centrifugation, and then washed with an equal amount of demineralized water containing 0.05% non-ionic surface the surface-active agent, consisting of fatty alcohol (a mixture of fatty alcohols C13-C15), condensed with ethylene oxide and propylene oxide supplied by the company Huntsman under the trade name Empilan 2638 (simple ether containing 3 mol of ethylene oxide and 7 moles of propylene oxide).

The granules were then separated by centrifugation and placed in a column with a diameter of 10 cm and a height of 80 cm for drying air at 23°With (flow rate of 3000 l/h). The time required for drying was 10 minutes.

To the thus obtained granules were added the same additives as in comparative example 1, the granules were screened and further processed in accordance with the procedure outlined in comparative example 1, reaching a density of 15 g/L. it was Found that the duration of the cooling block was 10 minutes, and the sintering is 50%.

In the bottle of capacity of 200 g was placed 50 g of the mother liquor after polymerization and washing, and was stirred for minutes, checking for the presence of foam. In this case, the foam was formed.

Examples 2-4

Repeating example 1 with the use of other nonionic surfactants instead of Empilan 2638. The results are shown in the table.

EUR. app.1EUR. PRExample 1Example 2Example 3Example 4
Drying time, min 40111091112
The foam height, cm1100220
The time of the disappearance of the foam, min106 cm after 10 min00,510
NaDDB (%)-0,05----
Empilan 2638 (%)--0,05---
Voranol 4555 (%)---0,05--
Empilan NP (%)----0,05-
Armotan PN020 (%)-----0,05
Voranol 4555 - simple ester of glycerol with 20 mol. EA and 30 mol. ON

Empilan NP - Nonylphenol with 5 mol. EA

Armotan PN020 is a simple ester of sorbitol with 20 mol. EA.

1. The method of obtaining expanded onto vinylaromatic polymers, which includes

a) polymerization in aqueous suspension of at least one vinylaromatic monomer in risotti a suspending agent, selected from inorganic salts of phosphoric acid;

b) removing the expanded onto granules of the reaction vessel;

c) washing the obtained in this way granules with an aqueous solution containing 0.005-2 wt.% non-ionic surface-active agent;

d) removing the washed granules, the surface of which essentially contains no inorganic salts of phosphoric acid, and drying of these granules in the air stream.

2. The method according to claim 1, in which the polymerization vinylaromatic monomer in aqueous suspension is carried out in the presence of an initiating system and a blowing agent.

3. The method according to claim 2, in which the initiator system includes two peroxide, one with a half-life equal to one hour at 85-95°and the other with a half-life equal to one hour at 110-120°C.

4. The method according to claim 2, in which the foaming agent, which may be enclosed in a polymer matrix, consists of liquid substances with boiling points in the range from 10 to 100°C.

5. The method according to any one of claims 1 to 4, in which the foaming system is added in such quantities as to obtain a polymer in the form of granules, which can be converted into foamed articles having a density in the range from 5 to 50 g/l

6. The method according to claim 1, in which vinylaromatic monomer selected from monomers, suitable the General formula

where n is zero or an integer in the range from 1 to 5; R is a hydrogen atom or methyl; Y is halogen, such as chlorine or bromine, or alkyl or CNS radical containing from 1 to 4 carbon atoms.

7. The method according to claim 1, wherein the nonionic surface-active agent selected from alcohols/C8-C18ethoxylated and/or propoxycarbonyl fatty acids, ethoxylated and/or propoxycarbonyl ethers of glycerol with an average molecular mass Mwin the range from 3500 to 5000, glycols, condensed with ethylene oxide and/or propylene oxide, ethoxylated and/or propoxycarbonyl nonylphenols containing 0-5 parts of ethylene oxide and/or propylene oxide, ethoxylated and/or propoxyethanol sorbitol containing 5-20 parts of ethylene oxide and/or propylene oxide, potassium salts of fatty acids of coconut oil, methylethylamine.

8. The method according to claim 1, in which the flushing usually occurs at a temperature in the range from 20 to 50°in vessels with stirring, containing the surface-active agent at a concentration in the range from 0.01 to 2 wt.%, preferably from 0.02 to 1%.



 

Same patents:

FIELD: building industry; other industries; methods and devices for production of the granulated expanded polystyrene from the granules of polystyrene.

SUBSTANCE: the invention is pertaining to the methods of production of the granulated expanded polystyrene from the granules of polystyrene containing isopentane or pentane, which is used as the filler for the concretes and also for the monolithic and prefabricated heat insulation of the buildings and structures with application of cement. The method of foaming provides, that the granule of polystyrene are exposed to treatment with the seam at the temperature of 95-105°ะก at continuous stirring action. At that the granule of polystyrene are treated with superplasticizers for the mortar and the concrete having concentration of 20-40 % in quantity of 0.3-0.4 % of the mass of the polystyrene in the air-steam medium at the pressure of 0.35-0.4 MPa. The device for realization of the method contains: the control system; the loading tank for the source granules of the polystyrene connected with the foaming assembly, which includes the paddle mixer and the assembly of the steam feeding in. The outlet of the foaming assembly through the gear of the granules unloading and through the pneumatic pipe duct with the adjustable shutters is connected to air-separators of the hoppers for ageing of the granules. The hoppers include the means for their unloading connected through the unloading pneumatic pipe duct having the controlled shutter, which is connected to the air-separator of the loading tank. The loading tank and the hoppers for ageing of the granules are supplied with the vertical material pipe duct with inlet and outlet holes arranged accordingly on the upper and the lower controlled levels, in the lower part of which there is the sensor of control over the availability of the material. The device is supplied with the tools for treatment of the granules with the liquid superplasticizers for the concrete and the mortar, which are mounted flush with the spin axis of the worm feeder and perpendicularly to it and containing the tank with the sensor unit of availability of the material. The tank is connected to the spray assembly by means of the plug valve regulating the superplasticizer feeding by the pneumatic cylinder connected with the air collector through the pneumatic distributor. The assembly of the steam feeding in contains four perforated disks-sprayers, the total of the diameters of which is equal to the radius of the bottom of the foaming assembly and which are arranged according to the coordinates: the first disk - [0, r], the second disk - [3r, 0], the third disk - [-5r, 0], the fourth disk - [0,-7r] in the bottom of the foaming assembly, where r is the radius of the disks-sprayers of the steam. There also is the perforated grate in the form of the lattice with a mesh size of 0.14 mm mounted over the bottom along the whole area at the altitude equal to (0.05-0.1) from the height H of the working chamber of the foaming assembly, and the tubular shaft of the paddle mixer of the foaming assembly, which is made sealed above and connected with tubular vanes sealed on the ends and perforated from below. The invention ensures reduction of the granules density and the duration of the superlight expanded polystyrene production process, as well as the specific power inputs.

EFFECT: the invention ensures the decreased granules density, duration of the superlight expanded polystyrene production process, the specific power inputs.

2 cl, 3 dwg, 1 tbl, 14 ex

FIELD: polymer production.

SUBSTANCE: foamed vinylaromatic polymers are prepared using inorganic filler having essentially spherical granulation with average diameter within a range of 0.01 to 100 μm, refractory index exceeding 1.6, and whiteness index equal to or below 22 as measured according to "Color Index". Foamed vinylaromatic polymer include (i) matrix obtained by polymerization of 50-100% of one or more vinylaromatic monomers with 0-50% of copolymerizable monomer; (ii) 1-10% (based in polymer mass) of foaming agent incorporated in polymer matrix; and (iii) 0.05-25% of above-mentioned filler. Foamed vinylaromatic polymers are characterized by density from 5 to 50 g/L and heat conductivity 25 to 50 mv/m-K. A method of preparing foamed vinylaromatic polymers involving polymerization in water suspension of one or more vinylaromatic monomers, optionally in common with at least one polymerizable comonomer, in presence of inorganic filler is also described as well as continuous foamed polymer production process.

EFFECT: enhanced process efficiency.

4 cl, 2 tbl

FIELD: polymer materials in tobacco industry.

SUBSTANCE: invention relates to foamed material constituted by cross-linked amino-formaldehyde polymer product suitable for filtration of tobacco smoke. Foamed material according to invention contains cavities and intermediate spaces located outside of cavities, said spaces being confined by walls consisted of cross-linked amino-formaldehyde polymer product optionally supplemented by additives. Average space dimension lies within 30 to 350 μm. Considerable portion of spaces have two or more perforations with average diameter within a range of 5 to 300 μm in their walls while considerable portion of perforations of neighbor spaces are arranged relative to each other in such a way as to form continuous nonlinear path. Foamed material is characterized by porosity at least 45 vol % and specific surface area 0.1 to 15 m2/g. Method of preparing of such foamed material comprises following stages: mixing air and foaming agent solution under pressure in mixing zone of injector filled with multiple inert mixing members; passing, under pressure, non-hardened foam from mixing zone and prepolymer solution into reaction zone of injector to form curable foam; and discharging foam and drying it in air. Use of such foamed mixture as cigarette filter allows content of toxic compounds such as resins and polycyclic aromatic compounds to be lowered.

EFFECT: enhanced tobacco smoke filtration capacity.

6 cl, 10 dwg, 6 tbl

FIELD: polymer materials.

SUBSTANCE: method is comprised in saturating polymer material sample, placed in high-pressure cell, with carbon dioxide under supercritical conditions at pressure 250 atm and temperature 40-120°C, cooling the cell to room temperature and slowly lowering pressure to its atmospheric value. Foaming of polymer sample saturated with carbon dioxide under supercritical conditions proceeds during 60 min of further heat treatment at atmospheric pressure. Final porosity of polymer sample is determined by heat treatment temperature.

EFFECT: essentially preserved mechanical properties of initial polymer due to that, during heat treatment operation, outside layer of CO2-saturated polymer sample is foamed.

9 dwg, 1 tbl, 6 ex

The invention relates to pharmaceutical industry

The invention relates to an improved particulate, absorbent, polymeric compositions

The invention relates to the production of PVC plastisols with coloured compounds, which serve as the basis for the manufacture of krasavitsa materials in the form of various rollers of printing machines, stamp pad, marking stamps, etc

FIELD: polymer production.

SUBSTANCE: invention relates to foaming agent mixture composed of 1,1,1,3,3-pentafluoropropane and 1,1,1,2,3,3,3-heptafluoropropane, and also 1,1,1,2-tetrafluoroethane and/or 1,1,1,3,3-pentafluoropropane; to component containing above mixture, auxiliary substances or additives such as fire retardants or catalysts; and to incombustible mixture precursor containing polyols with ether and/or ester groups, which have molecular weight from below 400 and up to 10000 and more than 8 hydroxyl groups, and foaming agent mixture. Foaming agent mixture, component, and incombustible mixture precursor are destined for preparation of foamed plastics, particularly foamed polyurethanes.

EFFECT: improved inflammation temperature of mixtures intended for preparing high-quality foamed plastics.

6 cl, 2 ex

FIELD: polymer production.

SUBSTANCE: invention relates to production of polyurethane molded products having dense periphery and cellular core using a mixture of foaming agents, particularly containing 50-99% 1,1,1,3,3-pentafluorobutane (HPC 365 mfc) and 1-50% 1,1,1,2,3,3,3-heptafluoropropane (HPC 227 ea). Polyurethane molded products according to invention are characterized by density values varying between 300 and 600 kg/m3 and can be used as wood simulation.

EFFECT: expanded polyurethane foams production possibilities.

3 cl, 2 tbl

FIELD: chemistry of polymers, chemical technology.

SUBSTANCE: invention relates to the foaming agent compositions and to methods for preparing polymeric foams by using such foaming agent compositions, foaming polymeric composition comprising such foaming agents, and to polymeric foams comprising such foaming agents. The suitable combinations of foaming agents involve: (a) composition comprising above 50 wt.-% of carbon dioxide of the composition mass and above 0 wt.-% of at least one fluorinated hydrocarbon with the boiling point above 14°C but below 120°C; (b) composition comprising carbon dioxide and at least one fluorohydrocarbon with the boiling point above 30°C but below 120°C; (c) composition comprising carbon dioxide and at least one fluorohydrocarbon with the boiling point above 14°C and below 120°C and at least one fluorohydrocarbon with the boiling point below 14°C, and at least one additional foaming agent chosen from water, alcohols, ketones and aldehydes. Polymeric foams comprising the foaming agents compositions comprise additionally the infrared radiating blocking agent chosen from the group consisting of carbon black, graphite, gold, aluminum and titanium dioxide dispersed in the indicated polymer. Polymeric foams prepared by using the foaming agents compositions show heat conductivity value less 35 mWt/m x °K later 90 days after their preparing.

EFFECT: improved and valuable properties of composition and polymeric foam.

6 cl, 6 tbl

FIELD: organic chemistry, foaming agents.

SUBSTANCE: invention relates to foaming agent-containing compositions that comprise at least one fluorohydrocarbon with boiling point above 30°C and lower 120°C, at least one fluorohydrocarbon with boiling point lower 30°C and at least one component chosen from low-boiling alcohols and low-boiling carbonyl compounds excepting for CO2. The foaming-agent-containing composition can comprise additional foaming agent chosen from the group consisting of carbon dioxide, nitrogen, argon, water, air, helium, aliphatic or cyclic hydrocarbons. Also, invention relates to methods for preparing polymeric foams by using such foaming agent-containing compositions and to polymeric foams, foaming polymeric compositions comprising such foaming agent-containing compositions. Polymeric foams prepared by using foaming agent-containing composition have closed-porous structure and heat conductivity value less 35 mW/m x °K after 90 days of its preparing.

EFFECT: valuable properties of agent and composition.

4 cl, 4 tbl

FIELD: polymer production.

SUBSTANCE: invention relates to foamed polyurethane molded products with thickened edge zone with simplified density and clearly expressed more soft cellular core. Soft to semi-rigid polyurethane integral foamed plastics are prepared by interaction of (i) organic and/or modified organic polyisocyanates or their polymeric precursors with (ii) at least one polyol component with hydroxyl number 20 to 200 and functionality 2 to 6, if necessary in combination with (iii) at least one polyol component with hydroxyl number 201 to 899 and functionality 2 to 3, and also (iv) at least one component functioning as chain extension and having hydroxyl number or amine number 600 to 1850 and functionality 2 to 4 in amount 3 to 20% based on the summary weight of (ii) and (iii), and, if necessary, (v) known additives, activators, and/or stabilizers in presence of 0.05-0.6% water (based on summary weight of (ii) and (iii)) and mixtures of pore agents containing 1,1,1,3,3-pentafluorobutane and at least one other fluoroalkane in amount 0.2-10% of the summary weight of components (ii)-(v). Thus obtained foamed plastics with integral structure are characterized by Shore hardness of edge zone 30 to 90, rigidity in compression deformation 30 and 350 kPa, and apparent density 150 to 900 kg/m3.

EFFECT: increased assortment of foamed plastics.

7 cl, 1 tbl, 9 ex

FIELD: polymer materials.

SUBSTANCE: extruded polymeric foamed plastic with closed cells is claimed showing heat conductivity according to European Norm EN-13164 of the order of 30 mW/m·oK or below and characterized by a wide molecular weight distribution. Product contains residues of foaming agents from as-formed foamed plastic cells using mixture of foaming agents, which includes: main foaming agent (one or more fluorine-containing carbon compounds and optionally carbon dioxide) and secondary foaming agent (C1-C4-alcohol, linear or cyclic C1-C5-hydrocarbon, alkyl halide, water, or mixture thereof).

EFFECT: improved insulating ability and stabilized dimensions.

16 cl, 4 tbl, 4 ex

The invention relates to a method for producing an extruded foamed sheet thermoplastic, which, in particular, serve as the raw material for molding containers, vats, substrates, ceilings vehicle or packaging panels, pallets

The invention relates to a new method of production of rigid polyurethane foam with a predominantly closed cell rigid polyurethane foams obtained by this method as a layer constituent elements and material for filling cavities

The invention relates to foamed hydrocarbon polyurethane foams, which can be used in the refrigeration industry

FIELD: polymerization processes.

SUBSTANCE: invention provides a method for homopolymerization of acrylic acid and its salts or copolymerization of acrylic acid with one or several water-soluble monomers in solution in presence of suitable organo-sulfurized polymerization degree regulators according to invention. Thus prepared polymers are used as dispersing substances for mineral materials, for paper coatings, and as paper pulp fillers.

EFFECT: reduced polydispersity of polymers and enabled polymerization degree control according to desired industrial application.

32 cl, 16 tbl, 10 ex

FIELD: polymerization processes.

SUBSTANCE: invention provides a method for homopolymerization of acrylic acid and its salts or copolymerization of acrylic acid with one or several water-soluble monomers in solution in presence of suitable organo-sulfurized polymerization degree regulators according to invention. Thus prepared polymers are used as dispersing substances for mineral materials, for paper coatings, and as paper pulp fillers.

EFFECT: reduced polydispersity of polymers and enabled polymerization degree control according to desired industrial application.

32 cl, 16 tbl, 10 ex

Up!