RU2376331C1 - Thermoplastic polymer material - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: thermoplastic polymer material is described, which contains an organic thermoplastic polymer and a complex additive for improving moulding in amount of 0.02-1 wt %. The complex additive used is a composition which contains polyester with melting temperature ranging from 35 to 120°C and molecular weight of 1000-10000 Da, and thickeners, selected from polymers with molecular weight ranging from 100000 to 20000000 Da which are soluble in polyesters, finely dispersed powders of oxides of silicon and titanium with particle size ranging from 1 to 1000 nm and phosphorus-containing organic compounds.

EFFECT: proposed thermoplastic polymer material allows for reducing energy consumption and moulding temperature during its processing, and reducing loss of polymer during moulding.

9 cl, 16 dwg, 16 ex

Description

The invention relates to the processing of melts of thermoplastic organic polymers by extrusion, injection molding and inflation of a polymer sleeve. In particular, the claimed technical proposal is aimed at improving the processing of molten polyolefins with a narrow molecular weight distribution.

Processing of pure polymers by extrusion or injection molding, as a rule, is not performed. In practice, “polymer compositions” are processed containing various components in relatively small but often critical quantities. These components can be assigned to two classes, namely:

- additives to improve the properties of polymer products;

- additives to improve the formation of molten polymers,

see details in [J.T. Lutz Jr., R.F. Grossman. Polymer Modifiers and Additives. JL Enterprises, Bensalem Pennsylvania U.S. A. (2000) / 1 /] and [H. Zweifel, Plastic Additives Handbook. 5th Ed. Hanser Publishers: Munich (2000), / 2 /], [Flick E W (Ed.) (2001), Plastics Additives: An Industrial Guide, Knovel Corporation, N.Y. / 3 /].

Examples of additives for improving the properties of polymeric products are fillers and fillers, additives to improve mutual adhesion of components, anti-block additives, additives that improve the dispersion of fillers, dyes, plasticizers, a variety of chemical stabilizers and antioxidants. Anti-block additives, for example, are used to reduce the adhesion of polymer films to each other. These additives may include finely divided powders of synthetic quartz, diatomaceous earth, and talc.

Additives to improve the molding of polymers or processing additives facilitate the processing of polymers [E.S. Achlleos, G. Georgiou, S. G. Hatrikiriakos. Role of Processing Aids in the Extrusion of Molten Polymers. J. Vinyl & Additive Technology, 8 (2002) 7-24 / 4 /]. Often, recycling without them would not have been possible. Particularly important among these additives are lubricants, sometimes called “release agents,” which prevent the molten thermoplastic polymer from sticking to the equipment surface, for example, an extruder screw, mouthpiece, rollers, injection molding mold, etc. As an exception to the rule, some additives to improve the properties of polymer products are at the same time additives to improve the molding of polymers. For example, zinc stearate is both a lubricant and an inhibitor of the chemical decomposition of polymers at elevated temperatures.

When organic polymers, which are characterized by high molecular weight and narrow distribution, are formed by extrusion, a smooth extrudate can be obtained only below a certain molding speed. Above this limit, surface roughness begins to appear. The appearance of surface roughness, known to experts as melt crushing or “shark skin”, limits the productivity of polymer molding in industry. In order to increase the molding speed, additives are used to improve the molding of the polymers. The use of these additives should delay or eliminate the appearance of surface roughness.

Some fluorinated polymers, for example: Viton from DuPont, Dynamar from 3M, Kynar from Atofina, etc., see [S. Hatzikiriakos and K. Migler, Polymer Processing Instabilities: Control and Understanding for details. Marcel Dekker 2005. vol. 102. / 5 /], inhibit crushing of the melt and the appearance of defects such as "shark skin". Their use as additives provides higher extrusion molding performance. Such additives are usually used in an amount of from 0.025 to 0.3% by weight of the thermoplastic polymer material. The main problem that arises in the commercial use of these additives is the accumulation of decomposition products of additives on metal surfaces, for example, on an extruder screw and / or on the mouthpiece. The accumulation of decomposition products is often so intense that it is necessary to periodically stop the cleaning equipment. The use of these additives is also limited by their high cost. Fluorinated additives are hydrophobic substances, so their use increases the hydrophobicity of the surface of the polymer film.

Summarizing the analysis of analogues of the proposed technical solution associated with the use of fluorinated polymers, it can be noted that their disadvantage is the high cost and migration of hydrophobic polymers to the surface, which complicates the welding of polymer products by heating, reduces the adhesion of paint and glue to the polymer surface and leads to the accumulation of static electric charge on the surface of the film. The manufacture and use of fluorinated polymers leads to the emission of fluorinated gases into the atmosphere, which destroy the ozone layer of our planet and, possibly, cause cancer, so the use of additives based on fluorinated polymers is undesirable.

It is known that the use of complex processing additives, including a combination of boron nitride particles or delaminated clay with fluorinated polymers, as well as only delaminated clay particles, reduces the induction time for the processing additive and friction loss, see [E. B. Muliawan, N Rathod, SG Hatzikiriakos and M. Sentmanat. Boron Nitride and Fluoropolymer Combinations: Interactions and their performance as processing aids. Polym Eng Sci., 45, 669-677 (2005) / 6 /] and [S. G. Hatzikiriakos, N. Rathod and E. B. Muliawan, The Effect of Nanoclays on the Processability of Polyolefins. Polym. Eng. Sci., 45, 1098-1107 (2005) / 7 /]. The particles of clay and boron nitride are lamellar in shape. The thickness of the particles of delaminated clay can be about 1 nm, and the longitudinal size is from 300 to 600 nm. Particles of boron nitride for use in the processing additive have a size of 1-2 μm and a thickness of 30-60 nm, see [E. A. Pruss, T. M. Clere, S.K. Randa. Polymer processing aid and method for processing polymers. U.S. Pat. Appl. No. 20040220288 A1. Nov.4, 2004. U.S. C1 .: 521/50 / 8 /].

Summarizing the analysis of the analogues of the proposed technical solution associated with the use of complex additives, including a combination of mineral powders with fluorinated polymers, one can note the difficulty of mixing mineral powders with fluorinated polymers, which are characterized by high viscosity.

Organo-silicone additives, such as siloxanes, have been used effectively in industry for many years to improve polymer processing by injection molding, to facilitate the separation of products from the metal mold, and to increase the speed of extrusion molding. However, the use of these additives can be complicated by the difficulty of introducing them into the composition of the thermoplastic polymer material. For example, when these additives are fed together with the granular polymer material, the extruder screw slips and the material stops feeding. Additionally, high molecular weight siloxanes are hydrophobic substances that are characterized by low electrical conductivity. Siloxanes migrate to the surface of the product, and their presence reduces the adhesion of the surface of the product to glue, labels and paint, makes it difficult to weld polymer products, and also leads to the accumulation of static electric charge on the surface of the film, similar to the use of fluorinated processing additives.

Dow Corning has developed processing additives based on very high molecular weight siloxanes (15-20 million daltons). These additives are a dispersion of silicone polymer in a polymer matrix. The use of high molecular weight siloxanes eliminates slipping of the screw of the extruder and prevents the migration of additives to the surface of polymer products [http://www.dowcorning.com / 9 /]. Very high molecular weight siloxanes in the form of granules for use as a processing aid are also available from Wacker Chemie under the Genioplast trademark, see [http://www.wacker.com / 10 /], [M.Geek, P.Jerschow , G. Staiger, O. Fuhrmann. Pelletized organopolysiloxane material. U.S. Pat. Appl. No. 20050004296 A1. Jan. 6, 2005. U.S. C1 .: 524/492 / 11 /]. However, these additives are expensive, and a positive effect is achieved with a relatively high concentration in the mixture, which limits their use.

Summarizing the analysis of the analogues of the proposed technical solution associated with the use of siloxanes, it can be noted that their disadvantage is the relatively high cost, migration of hydrophobic polymers to the surface, which complicates the welding of polymer products by heating and reduces the adhesion of paint and glue to the polymer surface, leads to the accumulation of static electrical charge on the surface of the film.

Polyethylene glycols of various molecular weights and their derivatives are used in industry as components of a lubricant, brake and coolant, release agents for processing metals by pressing and cutting, for example, see [O. N. Dyment. Glycols and other derivatives of ethylene and propylene oxides. - M .: Chemistry, 1976.188 s. / 12 /], [Polyalkylene Oxides and Other Polyethers. ed. by N. Gaylord. New York, Interscience, 1963. 491 p. /13/]. It is known to use polyethylene glycol (PEG), PEG esters and high molecular weight polyethylene oxide (PO) as a release agent and processing aid. DeJuneas, et al. reported in their patent [J.V. DeJuneas, G. L. McClntyre, J.F. O′Horo Jr. Method of reducing breakdown in polyethylene film. U.S. Pat. No. 4,013,622. Mar. 22, 1977. U.S. C1 .: 524/388 / 14 /] that the addition of PEG with a molecular weight of 1300 to 7500 daltons in an amount of 0.02 to 0.05% by weight of the polymer material in the production of a polyethylene film reduces the number of shutdowns of the cleaning equipment under standard conditions work. L.E. Wolinski reported in his patent [L.E. Wolinski. Polyethylene resin containing a solid polyethylene glycol. U.S. Pat. No. 3,222,314. Dec. 07, 1965. U.S. C1 .: 260-32.2 / 15 /], that PEG with a molecular weight of from 1000 to 6500 daltons can be used in an amount of from 0.1 to 10 wt.% As additives in polyethylene to improve print quality on the surface of the polymer film. The use of polyethylene glycols with a molecular weight of less than 10,000, according to Duchesne, see [D.J.Duchesne, V. Bryce. Extrudable thermoplastic hydrocarbon polymer composition, U.S. Pat. No. 4,855,360, Aug. 8, 1989. U.S. CI: 525/187 / 16 /], does not provide an improvement in the quality of molding of polyolefins, in particular it does not suppress defects during extrusion of polyolefins with a narrow molecular weight distribution.

The use of PEG esters and fatty acids as a processing aid for processing linear low density polyethylene is described in [J. B. Williams, K.S. Geick. Melt processing additives for extrusion of polymers. U.S. Pat. Appl. No. 20020063359 A1. May 30, 2002. U.S. CI .: 264/211 / 17 /]. Dover Chemical recently announced its new Doverlube FL-599 brand product, which is a PEG and fatty acid ester. The product is intended for use as a processing additive for processing a number of polymers: high impact polystyrene (HIPS), polystyrene (PS), polyethylene (PE), polypropylene (PP), acrylic butadiene styrene (ABS) and polyvinyl chloride (PVC). It is also noted that it increases the transparency of polypropylene and can be used as a component of cleaning mixtures for extruders when changing the color of the polymer material and to reduce the decomposition of the polymer inside the extruder, see [http://www.doverchem.com / 18 /].

A proposal is known to use a high molecular weight PEG with a molecular weight of from 10,000 to 50,000 daltons as an additive to improve the formation of polyolefins, see [T. T. Tikuisis, et al. High molecular weight polyethylene glycol as polymer process aids. U.S. Pat. Appl. No. 20050070644 A1. Mar.31, 2005. U.S. CI .: 524/115 / 19 /]. Blong and Lavallee proposed using PEG and polyethylene oxide (PO) as a processing aid in extrusion processing of a fluorinated polymer, see [T.J. Blong, C. Lavallee. Meltprocessable fluoroplastic. U.S. Pat. No. 5,527,858. Jun. 18, 1996. U.S. CI .: 525/187 / 20 /]. The disadvantage of using high molecular weight PEG as an additive to improve molding is its high cost. The use of polyesters obtained by the polycondensation of carboxylic acids and polyhydric alcohols with a melting point up to 150 ° C as a processing aid for polyethylene is known from the patent [P.Bauer, U.Seeliger, U. Faller. Thermoplastic molding compounds based on ethylene polymers and thermoplastic polyesters. U.S. Pat. No. 6,048,937. Apr. 11, 2000. U.S. CI .: 525/131 / 21 /].

It is known to use mixtures of polyethers with inorganic powder with a particle size of from 3.5 to 12 microns as a processing additive. Corwin et al. in his patent [M.A. Corwin, G.N. Foster. Anti-block compounds for extrusion of transition metal catalyzed resins. U.S. Pat. No. 4,540,538. Sep.10, 1985. U.S. CI .: 264/211 / 22 /] reports that the accumulation of thermal decomposition products of polyolefins inside a hot extruder is reduced if a processing aid prepared by mixing PEG or polypropylene glycol (PPG) with a molecular weight in the range of 200 to 4,000,000 daltons in combination with phenolic is used antioxidant and inorganic anti-block additive with particle sizes from 0.5 to 10 microns. Li et al. described the use of binary mixtures of PEG and diatomaceous earth, which is usually used as an anti-block additive, in the ratio of 1 part PEG to 2 parts of diatomaceous earth and at a concentration of binary mixture from 0.5 to 3 wt.% to improve the processing of polyethylene and suppress extrusion defects of the type "Shark skin", see: [M.Xie, X.Liu, H.Li. Influence of PEG-containing additives on extrusion of ultrahigh molecular weight PE / PP blend. J. Appl. Polym. Sci. 100 (2006) 1282-1288 / 23 /], [X. Liu, H. Li. Effect of diatomite / polyethylene glycol binary processing aid on the melt fracture and the rheology of polyethylenes. Polym. Eng. Sci. 45 (2005) 898-903 / 24 /], [J. Chen, X. Liu, H. Li. Improvement in processability of metallocene polyethylene by ultrasound and binary processing aid. J. Appl. Polym. Sci. 103 (2007) 1927-1935 / 25 /]. Diatomaceous earth (crystalline quartz), which is used as an anti-block additive in the production of polymer films, is characterized by an irregular angular shape of particles with an average size of 3.5 to 12 microns, see [A.S. Cornett. Antiblock agent for polyolefin films. U.S. Pat. No. 5,908,890. Jun. 1, 1999. U.S. Class: 524/448 / 26 /]. The disadvantage of using a binary mixture of PEG with mineral powders with a particle size of from 0.5 to 10 μm is their low efficiency, so that to improve the molding it is necessary to use them in an amount of from 0.5 to 3 wt.%.

It is known to use esters of boric acid, PEG and / or propylene glycol as a release agent for treating metal molds for injection molding thermoplastic polymeric materials and for cleaning an extruder, see [S. Sato, Release agent for metallic mold. U.S. Pat. Appl. No. 20040083925 A1. May 6, 2004/27 /] and [S.Sato, Resin composition for purging contaminant in the plastic processing machine. U.S. Pat. Appl. No. 20040132878 A1. July 8, 2004/28 /]. It is significant that the polyester of boric acid, proposed for use as a release agent, has a molecular weight of 280 to 4600 daltons, that is, it is prepared using a polyester with a molecular weight of less than 1500 daltons, and the molar ratio of boron atoms to polyester molecules does not exceed 1/3. It follows from the description that the forms are coated with a brush, sprayed or immersed at room temperature in a liquid release agent, i.e. the specified liquid polyester of boric acid is not intended for use as a processing additive. For use as a component of a composition for cleaning the extruder and other equipment for molding polymer melts, said liquid polyester of boric acid is used as an additive in a ratio of 0.1 to 10 parts per 100 parts of thermoplastic polymer. When mixing boric acid liquid ester with granules, the screw of the extruder will slip and the material will slow down and may even completely stop. Therefore, the liquid polyester of boric acid is pre-mixed with the polymer material in the form of granules or powder and granules of the concentrate are formed using a special extruder.

Summarizing the analysis of analogues of the proposed technical solution associated with the use of polyesters and their derivatives, it can be noted that the known additives for improving the formation of polyesters are either expensive or insufficiently effective, so that the improvement of the molding of polymer products is achieved only with a high content of such additives in a thermoplastic polymer material.

The use of complex additives related to the combination of fluorinated polymers and PEG as a processing additive is widely known from the technical literature, see list:

[Fluoroelastomer processing aids meet extrusion needs. Plastics, Additives and Compounding. 4 (Jan. 2002) 23-25. DOI: 10.1016 / S1464-391X (02) 80025-3 / 29 /],

[D.J. Duchesne, V. Bryce, Extrudable thermoplastic hydrocarbon polymer composition, U.S. Pat. No. 5,015,693. May 14, 1991. U.S. CI .: 525/187 / 30 /],

[D.E. Priester. Processing aid system for polyolefins. U.S. Pat. No. 5,587,429. Dec. 24, 1996. U.S. CI .: 525/187 / 31 /],

[R. Chiu, J. W. Taylor, D. L. Cooke, S. K. Goyal, R. E. Oswin. Melt fracture elimination in film production. U.S. Pat. No. 5,550, 193. Aug. 27, 1996. U.S. CI .: 525/199 / 32 /],

[T.J.Blong, M.P. Greuel, C. Lavallee. Extrudable thermoplastic hydrocarbon compositions. U.S. Pat. No. 5,710,217. Jan. 20, 1998. U.S. CI .: 525/199 / 33 /],

[T.J.Blong, M.P. Greuel, C. Lavallee. Extrudable thermoplastic hydrocarbon compositions. U.S. Pat. No. 5,830,947. Nov. 3, 1998. U.S. CI .: 525/187 / 34 /],

[K.Focquet, G. Dewitte, S.E. Amos. Polymer processing additive having improved stability. U.S. Pat. No. 6,294,604. Sep.25, 2001. U.S. CI .: 524/433 / 35 /],

[G.R. Chapman JR and S.R. Oriani. Process aid for melt processible polymers. U.S. Pat. Appl. No. 20030236357 A1. Dec. 25, 2003. U.S. CI .: 525/415 / 36 /],

[S.S. Woods. Melt processable thermoplastic polymer composition employing a polymer processing additive containing a fluorothermoplastic copolymer. U.S. Pat. No. 6,734,252. May 11, 2004. U.S. CI .: 525/187 / 37 /],

[G.R. Chapman JR and S.R. Oriani. Process aid for melt processible polymers. U.S. Pat. Appl. No. 20040204544 A1. Oct. 14, 2004. U.S. CI .: 525/178 / 38 /],

[J. Briers, J. J. J. Cemohous, R. R. Nuyttens. Melt processable compositions. U.S. Pat. Appl. No. 20050101722 A1, May 12, 2005. U.S. CI .: 524/520 / 39 /],

[G.R. Chapman Jr., S.R. Oriani. Process aid for melt processable polymers. U.S. Pat. No. 6,894,118. May 17, 2005. U.S. CI .: 525/186 / 40 /],

[S.R. Oriani, S.D′Uva, V.P. Trilokekar. Process aid masterbatch for melt processable polymers U.S. Pat. No. 6,906,137. Jun. 14, 2005. U.S. CI .: 525/165 / 41 /],

[B. Barriere, A. Bonnet, J. Laffargue and G. Marot. Fluoropolymer-based masterbatch and its use for the extrusion of polyolefins. U.S. Pat. Appl. No. 20060025523 A1. Feb. 2, 2006. U.S. CI .: 525/1 / 42 /],

[G.R. Chapman JR and S.R. Oriani. Process aid for melt processable polymers. U.S. Pat. Appl. No. 20060116477 A1. Jun. 1, 2006. U.S. CI .: 525/165 / 43 /].

The combination of PEG with fluorinated polymers for use as a processing aid is commercially available under the trademarks Kunar and Dynamar. When using a combination of PEG and fluorinated polymers, the accumulation of a static discharge on the surface of the polymer film is not observed, and the friction losses and induction time for the processing additive are reduced.

Summarizing the analysis of analogues of the proposed technical solution associated with the use of mixtures of PEG and fluorinated polymers, it can be noted that their disadvantage is the high cost of fluorinated polymers and their harmful effects on the environment.

The use of thermoplastic elastomers (TPE) based on polyurethanes as additives to improve the molding of polymers was proposed in [O. Kulikov. Thermoplastic polymer material. RU 2275398. Apr. 27, 2006. MKI C08D 23/02 / 44 /]. A thermoplastic elastomer based on siloxane and diisocyanate for use as a processing aid is commercially available under the brand name Geniomer from Wacker Chemie.

PEG-based polyurethane polymers have been known since the late 1950s, see [E. Windemuth, H. Schnell, O.Bayer. High molecular weight polyether urethane polymers. U.S. Pat. No. 2,948,691. Aug. 9, 1960. U.S. CI: 260-2.5 / 45 /]. It is widely known to use water-soluble polyurethanes as thickeners in aqueous suspensions and solutions, see for example: [E.A. Blair and D.E. Hudgin. Hydrophilic polyurethane polymers. U.S. Pat. No. 3,822,238. Aug. 2, 1972. U.S. CI .: 260-75 NK / 46 /], [H. Meffert, S.N. Kim. Polyurethane and the use thereof for modifying rheological properties. U.S. Pat. No. 7,019,061. Mar. 28, 2006. U.S. CI .: 524/284 / 47 /].

Summarizing a review of the analogues of the proposed technical solution associated with the use of thermoplastic polyurethane elastomers, it can be noted that their disadvantage is the difficulty in manufacturing such polymers (high vacuum, accurate dosing of components and their chemical purity, accurate temperature regime of the synthesis process), which increases their cost.

In the industry of processing thermoplastic polymers, there is a significant need for inexpensive and effective additives that provide a product without compromising its mechanical and organoleptic properties. This is especially true for the production of films for use in packaging from polyolefins prepared on the basis of metallocene catalysts.

Closest to the proposed invention is a well-known technical solution for the use of a viscoelastic compound as a processing additive, which is a reaction product between chemical compounds containing boron and oxygen (hardener), and the main component of the compound, which is a polymer material capable of reacting with this hardener, which was recently proposed in [O. Kulikov. A method of molding a thermoplastic organic polymeric material, a composition of a thermoplastic polymeric material and a lubricant. RU 2288095 C1, Nov 27, 2006. IPC В29С 33/62 / 48 /]. Silanes or polyols, in particular polyethylene glycols, can be selected as the main component of the compound. These chemicals are inexpensive and approved for use in contact with food and skin. The mentioned technical solution includes, as a special case, the use of polyols and silanols as the main component of the compound, in a mixture with an inorganic filler, but the advantage of using a filler-thickener in the composition of this compound is not shown. It is not shown that the use of an inorganic filler-thickener with a particle size of 1 to 1000 nm in the compound increases the efficiency of the processing additive. Also, the advantage of using a mixture of polyols with silanols and borates, where silanols are from 1 to 10% by weight of the compound, is not shown. The use of silanols in a mixture with polyols, in particular polyethylene glycols, allows to increase the viscosity of the compound and the effectiveness of the processing additive.

The claimed invention is aimed at increasing the speed and quality of molding of a thermoplastic polymer material with a narrow molecular weight distribution, reducing its losses, energy consumption and molding temperature, as well as simplifying and cheapening the manufacture of additives to improve molding.

This result is achieved in that the thermoplastic polymer material includes an organic thermoplastic polymer as the main component and a complex additive to improve molding, in the following ratio of components, wt.%:

complex additive: 0.02-1;

thermoplastic polymer: the rest,

however, as a complex additive, a composition is used containing one or more polyesters selected from the group of simple and complex, linear and branched aliphatic polyesters with a melting point in the range from 35 to 120 ° C and with a molecular weight of from 1000 to 10,000 daltons, and one or several thickeners, in the following ratio of components, wt.%:

thickeners: 0.01-20;

polyesters: the rest,

and thickeners are selected from the following group:

soluble polyesters with a molecular weight of from 100,000 to 20,000,000 daltons,

fine powders of silicon and titanium oxides with particle sizes from 1 to 1000 nanometers,

chemical compounds containing phosphorus and oxygen from the following group: phosphorus oxides in oxidation states of phosphorus +3 or +5, oxygen phosphorus acids in oxidation states of phosphorus +3 or +5, esters of these phosphorus acids, acid salts of these phosphorus acids, and mixtures of these chemical compounds.

This result is also achieved by the fact that polyesters use polyhydroxy compounds that are selected from the group of polyethylene glycols with a molecular weight of from 1000 to 10,000 daltons, or a mixture of these polyethylene glycols with polyhydric alcohols, soluble in polyethylene glycols, or copolymers of polyhydric alcohols and polyethylene glycols, where the weight content polyhydric alcohols in a mixture or in a copolymer with polyethylene glycols does not exceed 20%.

The indicated result is also achieved by the fact that the organic thermoplastic polymer is selected from the group of polyolefins or a mixture of polyolefins with a narrow molecular weight distribution.

The indicated result is also achieved by the fact that the organic thermoplastic polymer is selected from the group of polyolefins or a mixture of polyolefins with a narrow molecular weight distribution.

The indicated result is also achieved by the fact that the organic thermoplastic polymer is selected from the group of polyethylene or a mixture of polyethylene with a narrow molecular weight distribution.

The indicated result is also achieved by the fact that the organic thermoplastic polymer is selected from the group of polyethylene or a mixture of polyethylene with a narrow molecular weight distribution.

The indicated result is also achieved by the fact that as a thickener or one of the thickeners containing phosphorus and oxygen, organic phosphates or phosphites are used, which are selected from esters of phosphoric or phosphorous acid, as well as mixtures and copolymers of these esters.

The indicated result is also achieved by the fact that polyethylene oxide with a molecular weight of from 100,000 to 20,000,000 daltons is used as a thickener or one of the thickeners.

Definition of Terms

Thermoplastic polymer material

The term "thermoplastic polymer material" or, for brevity, "thermoplastic material", "thermoplastic" means a material based on an organic polymer that softens and acquires the ability to plastic deform when heated to a temperature lower than its thermal decomposition temperature. The term "plastic deformation" means irreversible deformation without fracture under the influence of repeated or long-term load. Thermoplastic organic polymers related to the proposed technical solution include polyolefins, fluorinated polymers, vinyls, polystyrene, polyacryl and polymethacrylate, diene elastomers, thermoplastic elastomers and polyacetates. Another important group of polymers includes polyesters, polyamides, polycarbonates, polysulfones and polyurethanes. The third important group of polymers is thermoplastic cellulose ethers and esters, as well as elastomers, if they can be processed like standard thermoplastics.

The most preferred group of polymers are polyolefins, copolymers, terpolymers and mixtures of polyolefins with a narrow molecular weight distribution. Examples: HDPE (high density polyethylene), LLDPE (linear low density polyethylene), PP (isotactic polypropylene), EPR (ethylene / propylene copolymer elastomer), EPDM (ethylene / propylene / diene copolymer), EVA (ethylene acetate / copolymer / vinyl), EEA (ethylene / ethyl acrylate copolymer) and EAA (ethylene / acrylic acid copolymer), etc.

The thermoplastic polymer may also be a mixture of two or more of the polymers from this list. The aforementioned polymers and copolymers are known and commercially available, therefore, we consider their detailed description unnecessary. These polymers can be processed into plastic products in a variety of ways. The proposed solution is especially useful when molding polymers by extrusion and injection of melts of a thermoplastic polymer material.

Additive to improve the properties of polymer products and an additive to improve the molding of polymers (processing additive)

The definitions of the terms “additive for improving the properties of polymer products” and “additive for improving the molding of polymers” are made above in the review of the prior art. Additives to improve the molding of polymers (processing additives) are usually not thermodynamically compatible with thermoplastic organic polymers, i.e. when mixed, they do not dissolve and do not form a single phase with the main thermoplastic polymer. Such additives are intended to reduce molding pressure and eliminate molding defects.

Simple and complex polyesters

The term polyethers means hetero-chain polymers containing regularly repeating C — O — C groups in the main chain. Ethers are obtained by the polycondensation reaction of polyhydric alcohols (polyols) with polyalkylene oxides, for example, the reaction of ethylene glycol with ethylene oxide in the presence of a catalyst - caustic alkali. Aliphatic linear polyethers include polyacetals [-CHR-O-] n, where R = H or alkyl; alkylene oxide polymers [- (CHR) x-O-] n; copolymers of alkylene oxides with each other, with acetals or vinyl monomers. Polyethylene glycol (PEG) is a simple aliphatic linear polyester. The melting point of PEG with a molecular weight of 600 daltons is 17-23 ° C, for PEG 1000 is 35-40 ° C, and PEG 1500 is 44-48 ° C. The melting point of PEG increases with increasing molecular weight and reaches a value of 67 ° C, see [F.E.Bailey. Alkylene Oxides and Their Polymers. CRC Press Science, 1991. ISBN 0824783840] and [O. N. Dyment. Glycols and other derivatives of ethylene and propylene oxides. - M .: Chemistry, 1976].

A polyester is a category of polymers that contains a functional group of the carboxylic acid ester C (O) -O- in its main molecular chain. Carboxylic acids are a class of organic compounds whose molecules contain one or more functional carboxyl groups —COOH. Polyesters are usually prepared by a polycondensation reaction between a polyhydric alcohol (polyol) and a polybasic carboxylic acid, for example, linear polyesters are obtained in the reaction between a diol and a dicarboxylic acid. Esters obtained in the reaction between a polyhydric alcohol and a polybasic inorganic acid, for example boric acid, phosphoric acid, phosphorous acid, sulfuric acid, can be primary, secondary, and tertiary, i.e., with the substitution of one, two, or three hydrogen atoms. Esters derived from polyethylene glycol with a molecular weight of from 1000 to 10,000 daltons and a polybasic acid are hydrophilic substances. High molecular weight polyesters typically have a melting point higher than polyethers. All aromatic polyesters usually have a high melting point. An example of an aromatic polyester is polyethylene terephthalate (PET), its melting point is + 260 ° C.

For the purposes of this technical proposal, aliphatic polyesters preferably contain at least one hydroxyl group in the molecule. Even better, if aliphatic polyesters contain at least two hydroxyl groups. Hydroxyl groups can be located at the ends of the molecule, they can be distributed along the molecule, or they can be located at the ends and along the molecule. When hydroxyl groups are located only along the chain, then the end groups can be any non-reactive group, for example, a methyl group. Additionally, it is preferable to use polyhydroxy aliphatic polyesters, and it is most preferable to use polyethylene glycols with a molecular weight of from 1000 to 10,000 daltons. For the purposes of the proposed technical solution, mixtures based on such polyethylene glycols can be used, as well as a mixture including low molecular weight polyhydric alcohols, for example, glycerin, polymerized glycerin, xylitol, sorbitol, mannitol and hydroquinone, provided that the melting temperature of this mixture is not lower than 35 ° FROM. For the purposes of the proposed technical solution, copolymers based on these polyethylene glycols and polyhydric alcohols can be used.

Siloxanes and Silanol Fluids

Siloxanes are a class of compounds that are both organic and inorganic compounds, and which consist of silicon, oxygen, hydrogen and other chemical groups, such as alkyl groups. Siloxanes are also known as “silicones” or “silicone elastomers”. A siloxane liquid or resin is a polymeric material with a molecular weight ranging from 20 to 2,000,000 daltons [http://www.fluorochemsilanes.co.uk / 49 /]. Molecules can be linear, cyclic or branched. Siloxanes can be characterized by both low viscosity (from 1 to 100,000 mPa-s) and high viscosity (from 100,000 to 2,000,000 mPa-s). For the purposes of this technical proposal, siloxane liquids and resins are used that contain at least two hydroxyl groups in the molecule, i.e. silanols. Preferably, the hydroxyl groups are located at the ends of the molecules in the form of dimethylhydroxyloxy, diphenylhydroxyloxy or dimethyl phenylhydroxyloxy. Alkyl groups in the composition of silanols include methyl, phenyl, and vinyl groups, and the most preferred methyl group. Without limiting the generality of the claimed technical solution, examples of silanol liquids include block copolymers of siloxane with simple and complex polyesters or with polycaprolactone, as well as mixtures thereof. For the purposes of the proposed technical solution, silanols with a molecular weight of from 20 to 2,000,000 daltons can be used. The molecular weight of silanols is limited by the fact that high molecular weight silanols are characterized by high viscosity, and too viscous silanols will be difficult to mix with other components of the complex processing additives.

Viscoelastic material, viscoelastic fluid

Elastic material under load can change shape and size without breaking and restore its original size after unloading. Viscoelastic material is defined in the literature as that material that has both elastic and viscous properties. Viscoelastic materials can exhibit both a decrease and an increase in viscosity with an increase in the loading speed. A viscoelastic fluid is a viscoelastic material that can flow under load. The mechanical properties of viscoelastic materials are characterized using the dynamic Young's modulus, G * = G1 + iG2, and the loss tangent tan (.alpha.) = G2 / G1, i.e. the relationship of the imaginary part of Young's modulus G2 to its real part G1. A material is considered elastic if G1 / G2> 1 or the loss tangent tan (.alpha.) <1. A material is considered viscous if G1 / G2 <1 or the loss tangent tan (.alpha.)> 1. The mechanical properties of viscoelastic materials vary with the load frequency. Most polymer melts exhibit viscous behavior (G1 / G2 <1) at low frequencies and elastic behavior (G1 / G2> 1) at high load frequencies. The complex viscosity is determined through the dynamic Young's modulus as .eta. * = | G * | / (2.pi.f), where f is the frequency of the applied load. In the literature, the terms “elastic-viscous material” and “elastic-plastic material” are sometimes used, especially to indicate the predominantly elastic behavior of the material in the frequency range characteristic of its processing or use.

Sol, suspension, suspension, gel, jelly

Organosol is a colloidal solution consisting of very small particles of 1-1000 nm, uniformly distributed in an organic liquid. Sols differ from coarsely dispersed systems (suspensions, emulsions) in particle size. Stable suspensions that do not settle by gravity are called suspensions. An increase in the concentration of the dispersed phase in the ash leads to the appearance of coagulation contacts between particles and the beginning of structuring — gelation. Coagulation structures are characterized by low strength, determined by van der Waals and hydrogen forces. Coagulation structures are characterized by complete spontaneous recovery after mechanical failure. A further increase in the volume concentration leads to a gradual disappearance of the ability to thixotropic reduction, and as the content of the dispersion medium decreases, the elastic and plastic properties are lost, see [“Chemical Encyclopedia”, - M .: ed. "Soviet Encyclopedia", 1988/50 /].

In the Russian-language technical literature, a gel is defined as a suspension of finely dispersed particles in coagulation contact with each other, in contrast to jelly, which is a network polymer swollen in a solvent. A variety of jellies are systems in which stable contacts between macromolecules are provided by local crystallization of a group of chains. At temperatures above the melting point of crystalline nodes, jellies are converted into polymer solutions. The gelatinous state of polymer-solvent systems also occurs in the case of interaction with a solvent of polymers having an ultrahigh molecular weight. The properties of the intermolecular chain weave network are similar to those of networks with chemical or crystallization sites. Even with prolonged mechanical action, large, almost completely reversible deformations develop in such a system, although such a gelatinous state is unstable due to the gradual rearrangement of intermolecular contacts. These systems occupy an intermediate position between jellies and viscoelastic polymer solutions. In foreign (English) technical literature, the term jelly refers almost exclusively to food products, while crosslinked polymer systems swollen in a solvent, solutions of block copolymers and ultra high molecular weight polymers, showing reversible deformations and elastic properties, are referred to gels (gel) together with coagulated suspensions of finely dispersed inorganic particles in water or organic solvents.

Thickeners passive and active

The term "thickener polymer fluid" means a substance that increases the viscosity and elasticity of this polymer fluid when mixed with it, but so that it retains its ability to flow under load. The thickener does not have to dissolve in the polymer liquid, but form a sol or suspension in it. A thickener can be called passive if it does not chemically react with a polymer liquid. Examples of a passive thickener: highly dispersed silicon dioxide (white soot) with particle sizes from 1 to 1000 nm, metal salts and carboxylic acids soluble in the polymer liquid, high molecular weight polymers and block copolymers soluble in the polymer liquid, as well as suspensions of high molecular weight polymers and block copolymers, swelling in this polymer fluid. Passive thickeners are often used in industry to create sols, gels, jellies, suspensions, and pastes. For example, to thicken petroleum oils in order to obtain grease, the industry makes extensive use of soaps (salts of higher carboxylic acids, as well as: lithium, potassium, sodium, calcium, aluminum, zinc), urea, bentonite, highly dispersed silicon oxide, see [T .Mang and W.Dresel (Eds). Lubricants and Lubrication (2-nd Edition), Wiley-VCH Verlag GmbH & Co. KgaA. 2007/51 /]. Thickeners differ in the specific effectiveness of increasing viscosity. The content of passive thickeners in grease is in the range from 5 to 40%, and usually from 10 to 15%.

To thicken aliphatic polyesters, the industry uses highly dispersed mineral particles with sizes from 1 to 1000 nm, i.e. colloidal particles, see for example [M. Brauer, Y. C. Chu. Cable grease composition and articles incorporating same. U.S. Pat. No. 5,348,669. Sep.20, 1994. U.S. CI .: 508/136 / 52 /]. Other thickeners for polyethylene glycols and their derivatives are known from the technical literature. For example, the use of lithium salts is known, see [T.R. Forbus, Jr. Polyglycol lubricants measuring trifluoromethane sulfonate. U.S. Pat. No. 4,569,774. Feb. 11, 1986. U.S. CI .: 508/406 / 53 /]. Cody et al. reported in the patent [S.L. Cody, M.R. Hoy, E.J. Roche, E.J. Walter. Soft gelatin pharmaceutical dosage form. U.S. Pat. No. 5,916,590. Jun. 29, 1999. U.S. CI .: 424/452 / 54 /] on the use of polyvinyl alcohol, cellulose ethers, copolymers of ethylene glycol and propylene glycol, sorbitol, as well as sodium stearate, sodium palminate and calcium acetate for thickening polyethylene glycols.

For thickening water-soluble aliphatic polyesters and, in particular, for thickening polyethylene glycols, you can use high molecular weight polyhydroxy compounds soluble in water, but insoluble in the polyethylene glycol itself, for example, selected from the group: polyvinylpyrrolidone, polyacrylamide and some polysaccharides and their . Such high molecular weight polymers swell in polyethylene glycol. Their stable suspension (suspension) in polyethylene glycol can be prepared using water as a common solvent, and then remove the water by evaporation.

As a thickener, you can also use such substances that react with a polymer liquid. An active thickener that reacts with a polymer fluid, here we also call a "hardener". The term "curing" corresponds to a change in the properties of the polymer system and the formation of chemical bonds during the reaction, which, for example, may be condensation, polymerization or vulcanization. Active thickener, i.e. hardener can react with a part of a low-viscosity polymer liquid with the formation of not a continuous spatial network, but a block of a copolymer dissolved in this liquid. The product of this reaction works as a passive thickener. For example, mixing polyesters and polyisocyanates, provided that the amount of polyisocyanate is less than stoichiometric, can lead to the formation of a high molecular weight branched polyurethane-polyurea block copolymer in the volume of the polyester, but an excess amount will lead to the formation of a three-dimensional polymer network. A polymer fluid crosslinked into a three-dimensional network does not show thermoplastic properties. When using polyesters with hydroxyl groups, i.e. polyols, the amount of isocyanate groups should be less than the number of hydroxyl groups of the polyol. Advantageously, the amount of isocyanate groups should be less than two thirds of the number of hydroxyl groups of the polyol in the mixture.

The industry uses polyisocyanates, in particular diisocyanates, to thicken mineral oils. For this, high molecular weight amines are dissolved in mineral oil and polyisocyanates are added, which react with amines to form polyurea. Similarly, solutions of high molecular weight amines and polyamines in polyols can be used and the polyisocyanate added, provided that the molar amount of the polyisocyanate approximately corresponds to the stoichiometric ratio for the reaction with amines or polyamines. The reaction rate of the isocyanate group with an amine group is significantly higher than the reaction rate with a hydroxyl group, therefore, as a result of mixing the components, a polyol thickened with polyurea is obtained.

As a thickener, you can also use substances that, when mixed with polyesters, increase the hydrogen forces of interaction between the polyester molecules. For example, to thicken polyethylene glycols, polyhydric alcohols, phosphorus acids, esters of these acids, soluble in polyethylene glycols, for example, organic phosphites and phosphates, acid salts of these acids and metals, soluble in polyethylene glycols, acid salts of these acids and ammonium can be used. A special case of an active thickener, i.e. hardeners for polyhydroxy compounds, are such chemical compounds that contain boron and oxygen, as well as such chemical compounds that contain phosphorus and oxygen. These hardeners are discussed in more detail below.

A mixture of a polymer fluid with a passive thickener or a combination of passive thickener and hardener is called a compound. The mechanical properties of the polymer fluid and compound are measured at the molding temperature of the polymer material.

Borates and Boric Acids

As an active thickener (hardener) for low and high molecular weight polyhydroxy compounds, including silanols, simple and complex aliphatic polyesters containing at least two hydroxyl groups, i.e. polyols, you can use such chemical compounds that contain boron and oxygen: boron oxide, boric acids, water-soluble salts of boric acid, boric acid esters, acid salts of amines and boric acid, and mixtures of these substances. The term “boric acids” refers to three formulations: orthoboric acid (also boric acid, NHBO3 or B2O3 · 3H2O), metaboric acid (HBO or B2O3 · H2O), and tetraboric acid (also pyroboric, Н4 В4О7 or 2 (В2О3) · Н2О ) Examples of water-soluble salts of boric acid are alkali metal salts, ammonium salts, acid salts of alkaline earth metals. Economically attractive examples of water-soluble salts of boric acid are sodium metaborate (NaBO2), and sodium tetraborate (Na2B4O7). Boric acids and boron oxide, when heated to 100-170 ° C, readily react with polyhydroxyl compounds to form ethers: simple alcohols, phenols, glycols, glycerols, polyhydric alcohols, polyvinyl alcohol, monosaccharides, disaccharides and polysaccharides. Boric esters include mono-, di- and tri-substituted organic boric acid esters.

The polycondensation reaction between an active thickener (hardener) containing boron and oxygen, and polyhydroxy compounds refers to reversible reactions. In the open air, i.e. in the presence of water vapor, the direct and reverse reactions are in equilibrium, i.e. covalent bonds in such a polymer system are broken and recreated with a characteristic time that depends on the amount of water in the system. With an increase in the amount of water in the system, the characteristic time of covalent bond existence decreases. If such a polymer system is under mechanical load, the time of which is shorter than the characteristic time of covalent bond existence, then it exhibits elastic properties, and under a long load it flows. The reaction products of hydrophobic silanols with borates exhibit elastic properties under mechanical load with a characteristic time shorter than 0.1 sec. Adding a small amount of hydrophobic silanols to hydrophilic polyols can reduce the amount of water in the system and increase the characteristic covalent bond lifetime averaged over the system. A catalyst can be used to accelerate the rate of the polycondensation reaction and shift the equilibrium towards the formation of borate and polyester compounds. Examples of catalysts for the condensation reaction and the exchange reaction between esters are known from the technical literature. In particular, the catalyst may be selected from the group consisting of inorganic acids, organic acids, metal salts of organic acids (iron, tin, lead, cobalt, manganese), some metal alkoxides (titanium, zirconium), tertiary amines, acid salts of amines and organic acids.

Phosphates, phosphites, oxides and acids of phosphorus (III and V)

As a passive and active thickener (hardener) for high molecular weight polyethylene glycols, one can use such chemical compounds that contain phosphorus and oxygen: phosphorus oxides in oxidation states of phosphorus +3 or +5; phosphorus oxygen acids in oxidation states of phosphorus +3 or +5; esters of said phosphorus acids, acid salts of said phosphorus acids, and also mixtures of said chemical compounds.

The concept of “phosphorus oxides in oxidation states of phosphorus +3 or +5” refers to the following substances: P2O3; P2O5. The concept of “phosphorus oxygen acids in oxidation states of phosphorus +3 or +5” refers to the following substances: phosphorous acid NZROZ; meta- (HPO3), pyro (H4P2O7) and ortho- (H3PO4) phosphoric acid. Oxides of phosphorus and phosphorus acid react with high molecular weight aliphatic polyhydroxy compounds. The conditions for such reactions are known from the technical literature. When using a mixture of phosphorus acids or phosphorus oxides with polyethylene glycols as a processing additive, the formation of esters of phosphorus acids and polyhydroxyl compounds partially occurs inside the extruder.

Attractive examples of an active thickener are esters of phosphorus acids and, above all, organic phosphites and phosphates. The term “organic phosphates” refers to phosphoric acid esters of the general formula (RO) nP (O) (OH) (3-n), where R is an organic group; n = 1 to 3, and salts of acidic esters of phosphoric acid. Organic phosphates are widely used in industry as additives for the modification of plastics (such as plasticizers, additives to increase fire resistance). The term "organic phosphites" refers to esters of phosphorous acid of the general formula (RO) nP (OH) (3-n), where R is an organic group; n = 1-3, and salts of acid esters of phosphorous acid. Organic phosphites (secondary and tertiary) are widely used in industry as an antioxidant for polymers. In industry, phosphites for use as an antioxidant are prepared predominantly from low molecular weight phosphites by transesterification reactions, i.e. exchange of low molecular weight alcohols with high molecular weight alcohols and glycols when heated in the presence of catalysts. For thickening polyethylene glycols, esters of phosphorus acids and polyhydric alcohols that have from 3 to 6 hydroxyl groups (glycerol, xylitol, sorbitol, mannitol) can be used, see [L. Friedman, Hydroxy propoxy propyl phosphites, U.S. Pat. No. 3,009,939, Nov. 21, 1961, U.S. CI .: 260-461 / 55 /], [N. Mayer, G. Pfahler, H. Wiezer, Phosipites of Polyalcohols, USA Pat. No. 4,207,270. Jun 10, 1980 U.S. CI .: 260/927 / 56 /]. When using a mixture of low molecular weight esters of phosphorus acids or acid salts of phosphorus acids with polyethylene glycols as a processing aid, the formation of esters of phosphorus acids and polyethylene glycols partially occurs inside the extruder by the transesterification reaction.

Organic phosphites, which are used in industry as an antioxidant, are described and classified in [D.R. Stevenson, T. C. Jennings, M.E. Harr, M.R. Jakupca. Phosphite ester additive compositions. U.S. Pat. No. 7,320,764, Jan. 22, 2008. U.S. CI .: 252 / 400.24 / 57 /]. Organophosphites at room temperature can be either liquid or solid substances with a melting point from 40 to 230 ° C. Most organic phosphites used as antioxidants are aromatic phosphites or mixed aryl-alkyl phosphites. Aromatic phosphites are easily hydrolyzed and form effective phenol stabilizers. When low molecular weight phosphites are mixed with high molecular weight polyethylene glycols and when the mixture is heated, a transesterification reaction occurs when the low molecular weight phenol or alcohol is cleaved and replaced with high molecular weight polyethylene glycol. When polyethylene glycol with a molecular weight of 1000 to 10,000 daltons is added to a polymer material containing organophosphites as antioxidants, and during melt processing, partial dissolution of antioxidants in the indicated polyethylene glycol occurs with an increase in the viscosity of the mixture due to an increase in the hydrogen forces of interaction between the polyethylene glycol molecules, and some of the components react inside an extruder with the synthesis of high molecular weight organophosphites, which serve as a passive thickener of polyethylene glycol.

Sulphuric acid. Sulphates

Improving the quality of molding is observed when using a mixture of these polyethylene glycols with sulfuric acid or sulfuric acid esters. However, sulfuric acid causes corrosion of the metal and cannot be recommended for use as a component of a processing additive.

For the purposes of the proposed technical solution, such a composition of a thermoplastic polymer material is used that contains a complex additive to improve molding in an amount of from 0.02 to 1 wt.%. The use of an additive in an amount of more than 1 wt.% Is allowed for accelerated reduction of friction losses during molding and for accelerated suppression of extrusion defects, as well as for the preparation of additive concentrate. The additive concentrate, with its content from 1 to 10 wt.%, Is used to more evenly distribute the specified additive in the polymer material, but the additional operation of concentrate preparation increases the cost of production. The use of a complex additive in an amount of less than 0.02 wt.% Does not provide a pressure reduction during molding of the polymeric material and suppression of defects in the molding of polymers with a narrow molecular weight distribution.

Polyethylene glycols with a molecular weight of 1000 to 10,000 daltons are cheap and are approved for use in contact with food and the human body. Polyethylene glycols are already used in industry as additives in the processing of polyethylene, for example, to improve printing on a polymer film or to improve the quality of welding of a polymer film by heating. The use of polyethylene glycols with a molecular weight of less than 1000 daltons with thickeners does not show an improvement in the molding of a thermoplastic polymer material. Moreover, the use of polyethylene glycols, such as the main component of the additive, leads to slipping of the screw in the screw extruder and a decrease in the supply of polymer material. Thus, the use of low molecular weight polyethylene glycols as the main component of a processing additive is not possible, but they may be present in small quantities in the mixture, provided that the melting point of such a mixture is at least 35 ° C.

The viscosity of polyethylene glycols at temperatures above their melting point increases sharply with increasing molecular weight, so the effect of using thickeners decreases for PEG with a molecular weight of from 6,000 to 10,000 daltons. PEGs with a molecular weight of more than 10,000 daltons are already used in industry as a processing additive without a thickener, but such PEGs are relatively expensive, so their use as the main component of the additive is not economically feasible. However, PEGs with a molecular weight of more than 10,000 daltons may be present in small amounts in the mixture.

For the purposes of the proposed technical solution, PEG mixtures with a molecular weight of from 1000 to 10,000 daltons with a small amount (less than 20%) of low molecular weight polyhydroxyl compounds can be used, for example, from the following list: glycerin, polymerized glycerin, xylitol, sorbitol, hydroquinone, low molecular weight polyvinyl alcohol. When using low molecular weight polyhydroxyl compounds in the composition of a processing additive in an amount of more than 20 wt.%, The effectiveness of the additive decreases.

To prepare a processing additive in accordance with the proposed technical solution, the thickener is mixed with polyester before molding, and then mixed with a thermoplastic polymer, or the polyester and thickener are separately, simultaneously or sequentially mixed with a thermoplastic polymer before molding.

Thickeners for polymer liquids are known from the technical literature. These are, first of all, colloidal mineral particles. Colloidal mineral particles, as a thickener for a polymer liquid, for example, petroleum oil, have long been used in industry. Advantageously, highly dispersed silicon oxide prepared by Aerosil technology or bentonite is used in industry. In the particular case of the implementation of the proposed technical solution, highly dispersed mineral oxide powders with particle sizes from 1 to 1000 nm are used as a thickener. For example, silicon oxide and titanium oxide obtained by Aerosil technology, i.e. the interaction of gaseous silicon tetrachloride or titanium with water vapor. Colloidal oxide powders can have a hydrophobic surface, which is achieved by treating them with silane vapors. The use of colloidal mineral powders in an amount of less than 0.02 wt.% Shows a small effect, and at a concentration of more than 20 wt.% Mixing them with a polymer liquid is difficult due to a significant increase in the viscosity of the mixture. Additionally, the use of more than 20% of these thickeners in the composition to improve molding is not economically feasible.

High molecular weight polymers and block copolymers soluble in this liquid in an amount of from 0.01 to 10% by weight are also used as thickeners for polymer liquids. Methods for mixing such thickeners with a liquid are described in the technical literature. The use of these high molecular weight polymers and block copolymers in an amount of less than 0.01 wt.% Shows a small effect, and when their concentration is more than 10 wt.%, Mixing them with a polymer liquid is difficult. To dissolve polymers with an ultrahigh molecular weight in an amount of more than 1-3 wt.% In a liquid, it is necessary to use a low-viscosity solvent, which after mixing the components is removed by evaporation. Therefore, the use as a thickener of high molecular weight polymers in an amount of more than 1 wt.% Is irrational, and the use of an amount of more than 10% is technically difficult.

It is known in the industry to use a thermoplastic block copolymer (elastomer) soluble in polyester as a thickener for the preparation of gels. Such a block copolymer is mixed with polyester at a temperature above the melting point of the elastomer. As a thickening agent, a high molecular weight thermoplastic elastomer based on a polyisocyanate with a high molecular weight alcohol or amine soluble in polyester can be used. In particular, such a thickener can be obtained by a method known in the industry, namely by mixing a high molecular weight amine with a polyester, and then adding a polyisocyanate to the solution. Advantageously, such a thickener can be prepared by dissolving a high molecular weight amine in polyester and adding diisocyanate to form a block of a urea copolymer.

As a thickener for polyethylene glycols, a polyisocyanate or a polyisocyanate prepolymer can be used. The thickener and polyethylene glycol are mixed in the form of powders or in the form of melts when heated. The amount of isocyanate groups in the mixture should be less than the number of hydroxyl groups of polyethylene glycols. Advantageously, the amount of isocyanate groups is selected to be less than two thirds of the number of hydroxyl groups. When using less than 0.1% polyisocyanate by weight of polyethylene glycol, the additive shows a slight improvement in molding quality compared to the use of polyethylene glycols without thickeners. The use of more than 10% polyisocyanate, provided that the number of isocyanate groups of polyisocyanates in moles is less than the molar amount of hydroxyl groups in polyethylene glycols, for example, mixing PEG 1000 with a high molecular weight isocyanate formate polymer is not economically feasible.

To thicken the polymer liquid, not only sols of mineral particles can be used, but also suspensions of polymer particles insoluble in this polymer liquid. Such suspensions are most stable if they swell in a polymer fluid. In particular, high molecular weight polymers soluble in water but not soluble but swellable in polyethylene glycol, for example, polyvinylpyrrolidone, polyacrylamide, can be used as a thickener for polyethylene glycols. Methods for preparing a suspension of polymer particles using a solvent or simple mixing are also described in the technical literature. The use of such polymers as thickeners in an amount of less than 0.1 wt.% Shows little effect, and the use of more than 10% of these thickeners in the composition of the additive to improve molding is not economically feasible.

As thickeners, metal salts of carboxylic acids soluble in polymer liquids, such as fatty acids, are also widely used in industry. The industry uses salts of higher carboxylic acids and the following metals to thicken polymeric liquids and to produce greases: lithium, potassium, sodium, calcium, aluminum, zinc. From the technical literature it is known that calcium acetate, sodium stearate and sodium palminate are used to thicken polyglycols. The use of salts such as thickeners in an amount of less than 0.1 wt.% Shows little effect, and the use of more than 1% of these thickeners as part of the additive to improve molding is not technically feasible, but can be used for other purposes, for example, to increase the stability of a thermoplastic polymer material when heating or increasing the resistance of the polymer material to flame.

As a thickener, you can use a passive thickener in combination with borates. Borates can be dissolved in polyesters, or used as a concentrated solution in polyhydric alcohols, for example glycerol, xylitol or sorbitol. Such a solution is solid at room temperature and can be used in powder form. Before molding, the borate solution powder is mixed with polyester, then mixed with a thickener, and then with a thermoplastic polymer; or prepare a solution of borates in polyester and this solution is simultaneously or sequentially with a thickener mixed with a thermoplastic polymer; or three components: polyester, thickener and borates, simultaneously or sequentially in any order mixed with a thermoplastic polymer. Mixing the components of the additive to improve molding can be done with heating or at room temperature. Advantageously, the thickener is mixed with the polyester powder at room temperature, and then this mixture and borates in a powder or solution are mixed at room temperature with a thermoplastic polymer. The number of borates is selected from the range of 0.1-19 wt.%, In terms of boron oxide. The amount of borates in an amount of less than 0.1 wt.% Does not show a significant improvement in the properties of the complex additive, and the addition of borates in an amount of more than 19 wt.% Reduces the effectiveness of the complex additive.

As a thickener, you can use silanol liquid in combination with borates. Silanols withstand prolonged heating without chemical decomposition, therefore, their use as part of a complex additive increases its stability and effectiveness at the temperature of molding a thermoplastic polymer material. The amount of silanol liquid is selected from the range of 1-10 wt.%. An amount of silanol liquid of less than 1 wt.% Does not show a significant improvement in the properties of the complex additive, and if the amount of silanol fluid exceeds 10 wt.%, The prepared powder or granules of the processing additive stick together during storage. The silanol liquid is mixed at room temperature with a powder of polyethylene glycols for subsequent mixing with borates and a thermoplastic polymer, or the silanol liquid is mixed with a powder or a melt of a solution of borates in polyethylene glycol. Mixing a silanol liquid with a powder of polyethylene glycol or a powder of a solution of borates in polyethylene glycol at room temperature provides a more uniform distribution in a thermoplastic polymer material. Mixing a silanol liquid at room temperature with polyethylene glycol powder for subsequent mixing with a hardener and a thermoplastic polymer has a technical advantage, since the rate of deposition of the complex additive components on the inner surface of the molding equipment is increased. The components of the additive are deposited on the inner surface of the molding equipment and react there at elevated temperature with an increase in the viscosity of the reaction product relative to the viscosity of the starting components.

As a thickener for polyethylene glycols, phosphorus oxides, phosphorus acids, sulfuric acid, acid salts of these acids, phosphorus acid esters or sulfuric acid esters can be used. These chemical compounds are characterized by strong hydrogen bonds. They also react with polyethylene glycols to form high molecular weight esters. As a thickener for polyethylene glycols, organic phosphates and phosphites, i.e. esters of phosphoric and phosphorous acids, for example liquid and solid organic phosphites, which are used in industry as antioxidant additives for polyolefins. High molecular weight polyethylene glycol reacts with organophosphites when heated by the transesterification reaction. Before molding, the ester of the indicated acids in the form of a powder or liquid or a mixture of these esters is mixed with polyethylene glycol, then mixed with another thickener, for example, highly dispersed quartz oxide, and then with a thermoplastic polymer; or prepare a solution of these esters in polyethylene glycol and this solution is simultaneously or sequentially mixed with a thickener with a thermoplastic polymer; or three components: polyethylene glycol, a thickener, and said esters, simultaneously or sequentially in any order mixed with a thermoplastic polymer. Mixing the components of the additive to improve molding can be done with heating or at room temperature. Advantageously, the thickening agent is mixed with polyethylene glycol powder at room temperature, and then this mixture and the above esters in powder or liquid are mixed at room temperature with a thermoplastic polymer. The amount of these phosphorus acid esters is selected from the range of 0.1-20 wt.% Of the total weight of the complex processing additive, in terms of phosphorus oxide. The amount of these phosphorus acid esters in an amount of less than 0.1 wt.% Does not show a significant improvement in the properties of the complex additive, and adding them in an amount of more than 20 wt.% Does not increase the effectiveness of the complex additive, but can be used for other purposes, for example, to increase the stability of the thermoplastic polymer material when heated or to increase the resistance of the polymer material to flame.

If metal-carboxylic acid-soluble salts of polyethylene glycol, or organic phosphites, or a mixture of these chemical components are used as a thickener, then such chemical compounds are often already present in some grades of polymer material produced by the industry. For example, mixtures of zinc stearate with organic phosphites are used as an antioxidant additive for polyethylene. To improve the molding of such a polymeric material, it is sufficient to add only polyethylene glycol.

The polyester may contain additives that reduce its thermal decomposition - antioxidants, such as hydroquinone. Additionally, the polyester may contain additives that inhibit metal corrosion, for example, tertiary amines. The use of antioxidants and additives to prevent metal corrosion in the composition of lubricants and release agents based on polyesters is known from the patent and technical literature. The proposed additives or reactive components for preparing the additive in an amount of from 1 to 10 wt.% Can be mixed with such a thermoplastic polymer material that is thermodynamically compatible with the main thermoplastic polymer, i.e. a concentrate of processing additives can be made. The concentrate can be granulated so that these granules can in turn be metered and mixed with the granules of the main component. The use of a processing aid concentrate provides a more uniform distribution of the additives in the thermoplastic polymer, but increases the cost of the manufacturing process. To simplify and reduce the cost of production, you can add the additive to the extruder in the form of a liquid at a temperature above its melting for mixing with the granules of the polymer material. Otherwise, the additive can be prepared in the form of granules and mixed at room temperature with granules of a polymer material for processing in an extruder. The proposed additive can be mixed with mineral pigments or anti-block additive and used to prepare the appropriate concentrates. Since the proposed processing additive has a low viscosity at the molding temperature, it improves the dispersion of mineral particles in the polymer material.

Without binding ourselves to theory, below we provide a tentative description of the mechanism of action of the additive. Industrial equipment for molding polymers are made from a variety of materials, but mainly from metals. Commonly used metals are steel, brass, bronze, nickel and aluminum alloys. In the process of molding a thermoplastic polymer material onto a metal surface that is in contact with the thermoplastic melt, a layer of a processing aid, which is characterized by higher adhesion to the metal, spontaneously precipitates from the melt. The presence of a separating layer of additives on the surface of the equipment provides many advantages in the formation of polymers. In particular, this layer acts as a lubricant and can suppress shark skin instability during extrusion of polymers with a narrow molecular weight distribution. The rate of deposition of additives from the melt of the polymer material increases in proportion to their amount in the thermoplastic, but also depends on the viscosity of the additives. The deposition rate of additives sharply increases if the melt viscosity of the polymer material exceeds the viscosity of additives at molding temperature by 10 or more times, see [Joseph D.D. Steep wave fronts on extrudates of polymer melts and solutions: lubrication layers and boundary lubrication Journal of Non-Newtonian Fluid Mechanics, 70 (1997) 187-203 / 58 /]. The thickener in polyester interacts with solvent molecules by intermolecular attraction forces and hydrogen forces. When using an additive with a thickener to form a thermoplastic polymer, the liquid polyester spontaneously deposits on the metal surface together with the thickener. A low-viscosity polyester flows down along the wall, and the thickener, due to interaction with the wall, separates and accumulates on the metal surface so that a thin layer of the mixture of polyester and thickener turns into a viscoelastic compound - a grease. The elasticity of the compound maintains a thicker layer of lubricant compared to the use of polyester without a thickener. At a very low concentration of thickener (less than 0.01 wt.%) In the polyester, the accumulation of thickener at the boundary with the metal is too slow, and at a too high concentration of thickener (10 wt.%), The rate of transfer of the additive decreases due to the increased viscosity of the mixture metal surface. When processing a polymer material that has a wide molecular weight distribution, for example high-pressure polyethylene, or a polymer containing a significant amount of a low molecular weight plasticizer, the proposed additive does not work effectively, since the amount of plasticizer or low molecular weight low viscosity polymer in the thermoplastic material exceeds the content of the additive, liquefies additive layer on the metal surface and prevents the accumulation of a thickener on the metal surface

The essence of the claimed invention is clarified by examples of implementation and drawings:

Figure 1 presents, for comparison, the characteristic curves of reducing friction losses in a steel mouthpiece 2 × 60 mm versus time for using 0.1 wt.% Of the known Viton processing additive and with the proposed additives based on polyethylene glycols PEG 1500, PEG 6000 and PEG 10000 s thickener.

Figure 2 presents the characteristic curves of reducing friction losses in a steel mouthpiece 2 × 60 mm from time to time using 0.1 wt.% Of known processing additives.

Figure 3 presents the curves of changes in the complex viscosity of mixtures of PEG 1000 and PEG 10000 with highly dispersed silicon oxide.

Figure 4. curves of changes in the mechanical properties (G1 / G2) of mixtures of PEG 1000 and PEG 10000 with highly dispersed silicon oxide are presented.

Figure 5 presents the dependence of reducing friction losses during the extrusion of polyethylene with additives (0.2%) from a mixture of PEG 1000 with silicon oxide on the content of silicon oxide.

Figure 6 presents the dependence of reducing friction losses during the extrusion of polyethylene with additives (0.2%) from a mixture of PEG 1000 with Polyethylene oxide (PO) on the content of PO.

Figure 7 presents the dependence of reducing friction losses during the extrusion of polyethylene with additives (0.1%) from a mixture of PEG 1500 with boric acid on the content of boron oxide.

On Fig presents the dependence of reducing friction losses during the extrusion of polyethylene with additives (0.1%) from a mixture of PEG 1500 with phosphoric acid on the content of phosphorus oxide (V).

Figure 9 shows the characteristic curves of reducing friction losses in a steel mouthpiece 2 × 60 mm versus time during extrusion of polyethylene with additives (0.2%) of a solution of borates (VM) in PEG 1500 and a mixture of this solution of borates with thickeners (the content of thickeners in mixtures of 2 wt.%): silicon oxide (AS), silanol (SP) and polyethylene oxide PO.

Figure 10 shows the characteristic curves of reducing friction losses in a steel mouthpiece 2 × 60 mm versus time during extrusion of polyethylene with additives (0.2%) of PEG 1500 and a mixture of PEG 1500 with thickeners (content in the mixture 4%): sodium stearate ( soap); titanium oxide (AT) and polyacrylamide (PAA).

Figure 11 presents the characteristic curves of reducing friction losses in a steel mouthpiece 2 × 60 mm from time to time when extruding polyethylene with additives (0.1%) from PEG 2000; a mixture of PEG 2000 with silicon oxide (content in the mixture 4%); a solution of borates in PEG 2000 (VM); a mixture of PEG 2000 with an MDI preprase polymer Suprasec (1088).

12 shows the characteristic curves for reducing friction losses in a 2x60 mm steel mouthpiece versus time during extrusion of polyethylene with PEG 1000 additives with polyethylene oxide (0.1 wt% PO in the additive) when the content of the additive in the mixture with polyethylene is 0.1; 0.2; 0.5; 1 wt. %%.

On Fig presents the characteristic curves of reducing friction losses in a steel mouthpiece 2 × 60 mm from time to time when extruding polyethylene with additives (0.2%) of a mixture of a solution of borates in glycerin (GL + BM), the specified solution in PEG 1500 with the addition of oxide silicon (GL + BM + AS) or with the addition of polyethylene oxide (0.1 wt.% PO in the additive) (GL + BM + PO), as well as a mixture of a solution of borates in glycerol with a hydrophobic ester and silicon oxide (AG + GL + BM + AS).

On Fig presents the characteristic curves of the reduction of friction losses in a steel mouthpiece 2x60 mm from time to time during the extrusion of polyethylene with additives of a mixture of a solution of phosphates and sorbitol in PEG 6000. The additive content in the mixture with polyethylene is 0.05 and 0.1 wt.%.

On Fig presents the characteristic curves of the reduction of friction losses in the steel mouthpiece 2 × 60 mm from time to time during the extrusion of polyethylene with the addition of a mixture of a solution of phosphates and sorbitol in PEG 1500 with the addition of highly dispersed silicon oxide as a passive thickener. The additive content in the mixture with polyethylene is from 0.025 to 0.1 wt.%.

On Fig presents the characteristic curves of reducing friction losses in a steel mouthpiece 2 × 60 mm from time to time when extruding polyethylene with additives (0.1%) from mixtures: PEG 1500 and phosphoric acid (RA), PEG and phosphoric acid and sorbitol ( PA + SO), PEG and phosphoric acid and sorbitol with the addition of highly dispersed silica as a passive thickener (PA + SO + AS), as well as a solution of Hostanox PAR 62 organophosphite (HTNX) in PEG 1500.

Implementation examples

The experiments were performed using the commercially available LLDPE grade "LL1201 XV" from ExxonMobil. This material was chosen because of its purity and low level of additives in its composition. The material has a density of 0.925 g / cm3, a melting point of 123 ° C and a melt index of 0.7.

The following materials were used in experiments that are reflected in implementation examples:

Dynamar E-15653 from the company 3M,

DuPont Viton Free Flow SC-PW,

Kynar from Atofina,

Geniomer 140 from Wacker Chemie,

Bayer Baycoll AD5027 Linear Polyester, 0.85 wt.% Hydroxyl equivalent,

Glycerin, Sorbitol,

Sodium Stearate

Boric Acid, Phosphoric Acid,

Organophosphite Hostanox PAR 62 from the company Clariant,

PAA polyacrylamide, molecular weight 11,000,000 daltons,

Polyethylene glycols: PEG-200, PEG-600, PEG-1000, PEG-1500, PEG-2000, PEG-4000, PEG-6000, PEG-8000, PEG-10000,

Polyethylene oxide, molecular weight 5,000,000 daltons, from Alfa Aesar,

PPDI diazocyanate (para-phenyl diisocyanate) Hylene from DuPont Polymer Specialties, NCO content 52.5%,

Huntsman Suprasec 1088 MDI prepolymer,

Silicone fluid DOW 3-0133 POLYMER from the company Dow Corning, the equivalent content of silanol groups (Si-OH) - 0.153%,

Highly dispersed silicon oxide Aerosil 300,

Fine titanium oxide Aerosil P25 from Degussa.

Example 1. Extrusion of polyethylene with known processing additives

The powder of the well-known Viton FF processing additive was mixed with polyethylene in an amount of 1 g of additive per 1 kg of polyethylene. The extrusion was carried out at a speed of about 40 mm / sec. A characteristic curve for reducing friction loss versus extrusion time is shown in FIG. It can be seen that the supplement does not begin to act immediately, but after about 35 minutes. This waiting time is also called induction time. It is important for the industry to know not only the induction time, but also the recovery time, i.e., the termination of the additive, if they switch to extrusion of the polymer without the additive. For this purpose, in the implementation examples, 1 kg of a mixture of polyethylene with an additive was extruded, and then pure polyethylene was extruded. The moment of change of polyethylene with additives to pure polyethylene is shown in Fig.2, and Fig.9 - Fig.13 vertical dashed line.

Powders of the known fluorinated processing additives Viton FF, Dynamar and Kynar were mixed with polyethylene in an amount of 2 g of additive per 1 kg of polyethylene granules. These mixtures of polyethylene with additives were loaded into an extruder screw. Extrusion was carried out at a speed of about 40 mm / sec. Extrusion of 1 kg of the mixture at this speed lasts about 2 hours 20 minutes. After extrusion of 1 kg of a mixture of polyethylene with additives, about 1 kg of pure polyethylene was extruded. The reduction in friction losses when using Dynamar is not much different from using Viton FF. When using fluorinated polymers Viton and Dynamar as processing additives, the extrudate accumulated a significant static electric charge. When using the Kynar additive (a mixture of fluorinated polymers, about 60 wt.%, With polyethylene glycol, about 40 wt.%), Charge accumulation did not occur, but a fluorinated polymer was accumulated around the mouth of the mouthpiece, which was oxidized in air.

A thermoplastic polyurethane elastomer (TPUE) was prepared from PEG 8000 and PPDI diisocyanate through the isocyanate prepolymer stage. The prepolymer was polymerized by the addition of diethyleneamine. Granules (1 g) of the following thermoplastic polyurethane elastomers: Geniomer (TPUE based on siloxane); Baymod (a polyester based TPUE) and a prepared TPUE based on PEG 8000 polyethylene glycol were each mixed with 1 kg of polyethylene pellets. By mixing borates and silanol with phosphoric acid additives as a catalyst, a product was prepared that resembled the well-known Silly Putty “jumping putty”. The preparation of additives based on silanol and borates is much simpler compared to the process of preparing a thermoplastic polyurethane elastomer. Pieces of Silly Putty product made from silanol and borates were also mixed separately with 1 kg of polyethylene granules. Mixtures of polyethylene with additives were used in an extruder screw. Extrusion was carried out as described above. The characteristic curves of the reduction of friction losses from the extrusion time are presented in FIG. 2. Comparison with Figure 1 shows that additives based on thermoplastic polyurethanes, in addition to Baymod, as well as an additive obtained by the reaction of silanol with borates, show a more effective reduction in friction losses than an additive based on Viton fluorinated polymers. It is further seen that these additives do not accumulate in the extruder. When using the Geniomer additive, a static electric charge accumulated, but less than when using Viton and Dynamar additives.

Example 2. The mechanical properties of mixtures of PEG with fine silica as a thickener

At a temperature of about 75 ° C, a number of samples of a PEG 10,000 mixture, as well as a PEG 1000 mixture with highly dispersed amorphous silica Aerosil 300, were prepared. Using a Rheotest RT-20 instrument, we measured the dynamic Young's modulus, depending on the frequency. Figure 3 presents the dependence of the complex viscosity, .eta. * = G * / f. Figure 4 presents the dependence of the ratio G2 / G1 at a frequency of 2.5 Hz on the content of silicon oxide in the mixture. It can be seen that near the content of silicon oxide in the mixtures of 7.5-8 wt.%, The elasticity of the mixture sharply increases. Similarly, an increase in the viscosity of the mixture was noted. An increase in the viscosity and elasticity of the mixture with an increase in the content of silicon oxide in the mixture corresponds to the establishment of coagulation contacts between colloidal particles of silicon oxide and the transformation of the mixture into a viscoelastic gel.

Example 3. Extrusion of polyethylene with PEG additives of various molecular weights with highly dispersed oxide powder as thickeners

To obtain the proposed additives, a thickener (highly dispersed silica powder Aerosil 300 or abbreviated AS) was mixed with PEG in the amount of 6 parts per 100 parts of PEG. Additives (2 g) were mixed with polyethylene granules (1 kg) and loaded into the feeder of the screw extruder. Extrusion was carried out at a speed of about 40 mm / s at a temperature of 185 ° C. For comparison, we extruded with pure PEG without a thickener. During the extrusion of polyethylene with PEG 200 additives with Aerosil 300 silicon oxide, a decrease in the material feed rate by 25-30% and current oscillations for rotation of the extruder motor were observed, which can be explained by the slip of the screw when feeding the material. During the extrusion of polyethylene with PEG 600 additives with Aerosil 300, a decrease in the material feed rate by 23–28% and current oscillations for rotation of the extruder motor at a constant rotation speed were observed. Shark skin extrusion suppression was not observed for both types of polyethylene glycol. When using PEG with a molecular weight: 1000; 1500; 2000; 4000; 6000; 8000; 10000 as the main component of the additive and highly dispersed silicon oxide powder as a thickener, we observed the suppression of shark skin extrusion defects, when friction losses were reduced by 15-20%. We also observed a slight (from 1 to 5%) increase in the extrusion rate at a constant screw rotor speed when using the additives of these PEGs with thickeners when the content of additives is less than 0.5 wt.%. Thus, the use of a PEG mixture with a molecular weight of from 1000 to 10 000 Daltons with a thickener allows to suppress shark skin extrusion defects and improve molding quality.

Example 4. Extrusion with additives of a mixture of PEG 1000 and fine silica as a thickener

To determine the effect of the amount of finely divided silica as a thickener on the efficiency of the processing additive, we used a mixture of PEG 1000 with Aerosil 300 silica. Polyethylene glycol was mixed with a thickener at a temperature of about 75 ° C with a content of 0.025; 0.1; one; 6 and 10 wt. %%. For uniform distribution of the thickener, an ultrasonic mixer was used. The prepared additive (2 g) was mixed with pure polyethylene (1 kg). Extrusion was carried out as described above. The dependence of the maximum friction reduction achieved on the content of highly dispersed silica is shown in FIG. 5. Assuming the continuity and monotony of the change in efficiency from the content of the thickener, it can be expected that the effect of the thickener will be noticeable when the content is in the range from 0.02 to 20 wt.%. Mixtures with a thickener content of 7 wt.% And higher are difficult to prepare because of their high viscosity. Thus, for the purposes of this technical proposal, the content of finely divided silica in the additive is preferably selected from the range from 0.05 to 7 wt.%.

Example 5. Extrusion with additives of a mixture of PEG 1000 and polyethylene oxide as a thickener

A mixture of PEG 1000 with high molecular weight polyethylene oxide (PO) with a molecular weight of 5,000,000 daltons was used to determine the effect of the amount of polyethylene oxide as a thickener on the efficiency of the processing additive. Polyethylene glycol was mixed with a thickener at a temperature of about 75 ° C with a content of 0.005; 0.025; 0.065 and 1 wt. %%. The prepared additive (2 g) was mixed with pure polyethylene (1 kg). Extrusion was carried out as described above. The dependence of the maximum friction reduction achieved on the content of polyethylene oxide is shown in Fig.6. Assuming the continuity and monotony of the change in efficiency from the content of the thickener, it can be expected that the effect of the thickener will be noticeable when the content is in the range from 0.01 to 10 wt.%. To prepare mixtures with a high molecular weight content of 1 to 10 wt.%, It is necessary to use a solvent, water, and remove it by evaporation after mixing the components. Thus, for the purposes of this technical proposal, the content of polyethylene oxide in the additive is preferably selected from the range from 0.02 to 1 wt.%.

Example 6. Extrusion of polyethylene with the addition of PEG 1500 with boric and phosphoric acids

Mixtures of boric acid with PEG 1500 were prepared with a boric acid content of 20 wt.%. When heated to 140 ° C, boric acid was dissolved and water was removed from the resulting solution in vacuum. By diluting the solution with pure PEG 1500, compositions with boric acid content were obtained: 1.25; 2.5; 5; 10 weight %%. The extrusion was carried out as described above, with an additive content of 0.1 wt.%. The dependence of the maximum achieved friction reduction on the content of borates in terms of boron oxide is shown in Fig.7. Assuming the continuity and monotony of the change in efficiency with the content of boron oxide, it can be expected that the effect of the thickener will be noticeable when its content is in the range from 0.4 to 20 wt.%. When using PEG with a molecular weight of from 6000 to 10000 instead of PEG 1500, the effect of the thickener is noticeable when the content of boron oxide is in the range from 0.1 to 20 wt.%.

A mixture of phosphoric acid with PEG 1500 was prepared with a phosphoric acid content of 10 wt.%. When heated to 160 ° C, phosphoric acid was dissolved and boric acid was added in an amount of 1 wt.% And water was removed from the resulting solution in vacuo. Diluting the solution with pure PEG 1500 gave compounds with a phosphoric acid content in wt.%: 0.1; one; 2.5; 5. The extrusion was carried out as described above, with an additive content of 0.1 wt.%. The dependence of the maximum achieved friction reduction on the phosphate content in terms of phosphorus oxide is shown in Fig. 8. Assuming the continuity and monotony of the change in efficiency with the content of boric acid, it can be seen that the effect of the thickener is noticeable when it is in the range from 0.2 to 20 wt.%. When using PEG with a molecular weight of from 6000 to 10000 instead of PEG 1500, the effect of the thickener is noticeable when the content of phosphorus oxide is in the range from 0.1 to 20 wt.%.

Example 7. Extrusion of polyethylene with additives of a solution of borates in PEG 1500 with thickeners

A solution of borates in PEG 1500 was prepared. A mixture of boric acid (24.8 g) and anhydrous borax (5 g) was used as borates per 1 kg of PEG. When heated to 100 ° C, borates were dissolved and water was removed from the resulting solution in vacuo. As thickeners of PEG 1500 with borates, highly dispersed silicon oxide Aerosil 300 (AS), polyethylene oxide (PO) and silanol polymer liquid D0W 3-0133 POLYMER (SP) were used in an amount of 6 parts per 100 parts of PEG by weight. For comparison, a solution of borates in PEG 1500 without thickeners was used. Additives (2 g) in the form of a powder were mixed with polyethylene granules (1 kg) and the mixture was loaded into an auger-extruder feeder. The extrusion was carried out as described above. The characteristic curves of the reduction of friction losses from time are presented in Fig.9. A comparison of the curves shows that the use of thickeners reduces friction losses.

Example 8. Extrusion of polyethylene with additives PEG 1500 with various thickeners

As a thickener PEG 1500 used polyacrylamide with a molecular weight of 11000000 daltons in the amount of 6 parts per 100 parts of PEG. Polyacrylamide swells in PEG, but is not soluble in it. Mixtures were prepared by dissolving PEG and a thickener in water and removing the solvent by heating. The final drying was carried out with heating in vacuum. In another case, a carboxylic acid salt, sodium stearate (soap), was used as a thickener in an amount of 1 part per 100 parts of PEG. The mixture was prepared by dissolving the soap in liquid PEG. A mixture of colloidal titanium oxide in an amount of 6 parts and 100 parts of PEG was prepared. For comparison, PEG 1500 without a thickener was used. The characteristic curves of the reduction of friction losses from time are presented in Fig.9. A comparison of the curves shows that the use of thickeners reduces friction losses, and as thickeners you can use metal salts of carboxylic acids, highly dispersed titanium oxide and high molecular weight polymers that are insoluble in PEG, but soluble in water and swellable in PEG.

Example 9. Extrusion of polyethylene with additives PEG 2000 with various thickeners

As a thickener PEG 2000 used highly dispersed (colloidal) powder of silicon oxide (4 parts per 100 parts of PEG); Suprasec 1088 MDI prepolymer (or 1088 for short) and a PEG borate solution in combination with finely divided silica. For comparison, PEG 2000 without a thickener was used. Mixtures were prepared with liquid PEG. After mixing, the product was ground at room temperature. The resulting powders were mixed with polyethylene granules with an additive content of 0.1 wt.%. The extrusion was carried out as described above. The characteristic curves of the reduction of friction losses from time are shown in FIG. 11. A comparison of the curves shows that the use of thickeners reduces friction losses.

Example 10. Extrusion of polyethylene with additives PEG 10000 with various thickeners

Colloidal silica powder (6 parts per 100 parts of PEG) or PPDI diazocyanate (0.16%, designated as ppdi; 0.8%, designated as PPDI) was used as a thickener for PEG 10000. For comparison, PEG 10 LLC without a thickener was used. Mixtures were prepared with liquid PEG. After mixing, the product was ground at room temperature. The resulting powders were mixed with polyethylene granules with an additive content of 250 ppm, i.e. 0.025 wt.%. Extrusion was carried out as described above. When using pure PEG 10000, a decrease in friction loss was recorded by 14.5%. The use of polyisocyanates as a thickener reduces friction losses compared to pure PEG 10000 by another 14% for ppdi (28.5%) and 19% for PPDI (33.5%). A mixture of PEG 10000 with PPDI diazocyanate (0.16%) in an amount of 3 g was mixed with 3 kg of polyethylene granules and used for extrusion, as described above. The characteristic curve is shown in FIG. 1 for comparison with an additive used in industry for improving molding based on fluorinated polymers. It can be seen that with the same content in the mixture, the proposed PEG-based additive with a thickener provides a more effective reduction in friction losses than the Viton fluorinated polymer-based additive used in industry.

Example 11. Extrusion of polyethylene with additives of a mixture of PEG 1000 with PO at different contents of the mixture

A mixture of polyethylene glycol PEG 1000 with polyethylene oxide (0.1%) prepared in Example 5 was mixed with polyethylene with an additive content of from 0.1 to 1 wt.%. The characteristic curves of the reduction of friction losses from time are presented in Fig. 12. It can be seen that the additive content of 1 wt.% Provides only a small decrease in friction losses compared to the additive content of 0.5 wt.%. It can be seen from the characteristic curve that when the content of the additive is 1% by weight, the time for which the additive can be removed from the extruder by extrusion of polyethylene without the additive is significantly extended. Additionally, it was found that the mass extrusion rate when the additive content of 1 wt.% Is reduced by 10% compared with extrusion without the use of additives. It can be concluded that the use of the proposed additives in an amount of more than 1 wt.% For extrusion is impractical, but can be used for extrusion of a polymer with fillers.

Example 12. Extrusion of polyethylene with the addition of polyester or PEG with thickeners and with the addition of hardener in powder

A solution of boric acid (boron oxide) and borax in glycerol (glycerol) was prepared: 100 g of boric acid and 25 g of anhydrous borax were taken per 100 g of glycerol. When heated to 100 ° C in vacuum, water was distilled from the solution. The resulting solution, resembling a clear and colorless fragile glass, was ground into powder at room temperature. Borate solution powder was used as a component of a complex processing additive in an amount of 16 g of a borate solution per 100 g of polyester with a thickener. The use of a borate solution as a separate component of a processing additive simplifies its manufacture. Extrusion was carried out with additives of a mixture of a hydrophobic Baycoll AD5027 polyester with Aerosil 300 as a thickener and with a solution of borates in glycerol at the component ratios indicated above. Liquid PEG 1500 was mixed with highly dispersed (colloidal) silicon oxide (1 part per hundred parts of PEG) or PO polyethylene oxide. The resulting mixtures were ground into a powder at room temperature, mixed with a powder of a solution of borates in glycerol and used similarly as described above as a processing additive with a content of 0.2 wt.%. Characteristic curves are shown in Fig.13. It is seen that in the case of using a hydrophobic polyester with a thickener and borates, the reduction in friction losses is less than for processing additives used in industry. It was further noted that when using hydrophobic polyesters as a component of a processing additive, the mass consumption of polyethylene at a given rotational speed of the extruder screw is reduced by 4-6%. This decrease can be explained by the slipping of the screw of the extruder.

Example 13. Extrusion of polyethylene with the addition of a solution of phosphates in PEG 6000

Organophosphate was prepared as follows: 18.1 g of sorbitol was mixed with 22.4 g of phosphoric acid and heated with stirring to 130 ° C until a dark amber color of the mixture was obtained. The resulting product in an amount of 3.7 g was mixed with 100 g of PEG 6000, heated to 130 ° C and cooled to room temperature. Additives (0.5 or 1.0 g) were mixed with polyethylene pellets (1 kg) and the mixture was loaded into the screw extruder feeder. Extrusion was carried out as described above. Additives (5 g) in the form of a powder were mixed with polyethylene granules (5 kg) and the mixture was loaded into an auger-extruder feeder. Extrusion was carried out as described above. The characteristic curves of the reduction of friction losses from time are shown in Fig. 14 by solid, dashed, and dashed lines.

Organophosphate was prepared as follows: 15.3 g of Sorbite (SO) was mixed with 49 g of phosphoric acid (PA) and heated with stirring to 130 ° C until a dark amber color of the mixture was obtained. The resulting product in an amount of 2.17 g was mixed with 100 g of PEG 6000, heated to 130 ° C and cooled to room temperature. Additives (0.25 or 1.0 g) were mixed with polyethylene pellets (1 kg) and the mixture was loaded into a screw extruder feeder. Extrusion was carried out as described above. Additives (2.5 g) in the form of a powder were mixed with polyethylene granules (5 kg) and the mixture was loaded into an auger-extruder feeder. Extrusion was carried out as described above. The characteristic curve of reducing friction losses over time for the use of 0.05% additives is shown in FIG. 14 with a dash-dot line, and for the use of 0.1% of additives is represented by a dash-dot line. The characteristic curve for the use of 0.025% is not shown, since the reduction in friction losses was negligible. It can be seen that with the same content in the mixture, the proposed PEG 6000 additives with an organophosphate thickener provide a more effective reduction in friction losses than the additive based on fluorinated polymers used in industry. An increase in the phosphate content in the composition of the additive provides a more effective reduction in friction loss with an additive content of 0.05%.

Example 14. Extrusion of polyethylene with additives of a solution of organophosphates in PEG 1500 and highly dispersed silicon oxide as a thickener

Organophosphate was prepared as follows: 2.0 g of sorbitol was mixed with 6.44 g of phosphoric acid and heated with stirring to 130 ° C until a dark amber color of the mixture was obtained. The resulting product was mixed with 41.5 g of PEG 1500, heated to 130 ° C and cooled to room temperature. As a passive thickener, 0.53 g of highly dispersed Aerosil 300 (AS) silica was added to this mixture. Additives (0.5 or 1.0 g) were mixed with polyethylene pellets (1 kg) and the mixture was loaded into the screw extruder feeder. Extrusion was carried out as described above. The characteristic curves of the reduction of friction losses from time are shown in Fig. 15. Additives (5 g) in the form of a powder were mixed with polyethylene granules (5 kg) and the mixture was loaded into an auger-extruder feeder. Extrusion was carried out as described above. The characteristic curve of the reduction of friction losses from time is presented in figure 1. When comparing the characteristic curves in FIG. 1, it can be seen that with the same content in the mixture, the proposed PEG 1500 additive with an organophosphate thickener provides a more effective reduction in friction losses than the Viton fluorinated polymer based additive used in industry.

Example 15. Extrusion of polyethylene with the addition of a solution of phosphates, polyhydric alcohol and highly dispersed silica in PEG 1500

50 g of PEG 1500 were mixed with 2 g of phosphoric acid. 50 g of PEG 1500 and 2 g of sorbitol were mixed with 4.3 g of phosphoric acid and 0.5 g of boric acid. 41.5 g of PEG 1500 were mixed with 2 g of sorbitol, with 0.5 g of finely divided silica and 6.44 g of phosphoric acid. Each mixture was heated to 160 ° C and water was removed from the resulting solution in vacuo. The resulting products were used as additives in polyethylene with the amount of additives of 0.1 wt.%. Extrusion was carried out as described above. The characteristic curves of the reduction of friction losses from time are presented in Fig.16. It can be seen that when using a mixture of PEG with highly dispersed silica, polyhydric alcohol and phosphoric acid, the proposed additive provides the highest reduction in friction losses.

Example 16. Extrusion of polyethylene with the addition of a solution of organo-sulfate in PEG 1500

In all of the above implementation examples, we used linear low density polyethylene that contained an antioxidant. Typically, industry uses mixtures of zinc stearate with organophosphites as an antioxidant. It was shown in Example 7 above that sodium stearate mixed with polyethylene glycol reduces friction losses. To study the effect of using mixtures of polyethylene glycol with organophosphates, 40 g of PEG 1500 were mixed with 10 g of organophosphite Hostanox PAR 62 from Clariant, which is used as an antioxidant for polyolefers. The characteristic curves of the reduction of friction losses from time are presented in Fig. 16. It is seen that the use of organophosphate in a mixture with polyethylene glycol reduces friction losses compared to pure PEG 1500.

In the technical literature it is noted that the use of pure polyethylene glycol as an additive in polyethylene that does not contain an antioxidant does not reduce friction. The decrease in friction losses with the use of pure PEG without a thickener in the implementation examples is explained by the presence of an antioxidant in the composition of the polyethylene used, which is a thickener for polyethylene glycol. An additional reduction in friction losses is observed when using the proposed processing aid compositions containing thickeners.

findings

Additives to improve the molding of a thermoplastic polymeric material, prepared on the basis of simple and complex, linear and branched aliphatic polyesters with a melting point of polyesters from 35 to 120 ° C with thickeners, were not known from the patent and special technical literature. The use of thickeners for the preparation of lubricants is widely used in industry, but such compositions are applied to the surface of rubbing parts, and are not used as additives in the molding of thermoplastic materials. It is not obvious from the prior art that the effectiveness of processing additives prepared on the basis of aliphatic polyesters will improve with the use of thickeners. From examples of the implementation of the proposed technical solution, it can be seen that additives can be used to improve the molding of thermoplastic polymer material in an amount of from 0.02% to 1%, and the amount of thickener to improve the effectiveness of the additive compared to using only polyesters without a thickener is necessary in an amount of 0.01 to 20%.

The use of a finely divided mineral powder with particle sizes from 1 to 1000 nanometers as a passive thickener of an aliphatic polyester differs from the use of a mineral powder with particle sizes above 3500 nanometers as a component of a complex processing additive known from the literature, see references and discussion above. The use of a finely divided (colloidal) mineral powder in combination with polyester also differs from the known use of delaminated clay powder alone or in combination of this powder with fluorinated polymer as a processing aid. The use of high molecular weight polyethylene oxide (PO) as an additive to improve the molding of a thermoplastic polymer is known from the literature, but the use of PO as a passive thickener in a complex processing additive based on polyethylene glycols was not known. The use of polyisocyanates as a component of a processing additive, when the molar amount of isocyanate groups is less than the number of hydroxyl groups in polyethylene glycol is not known from the technical literature and differs from the known use of thermoplastic elastomers and block copolymers based on diisocyanates as a processing additive. The use of a suspension of high molecular weight polymers that dissolve in water but do not dissolve in polyester but swell in it differs from the known suspensions of fluorinated polymer in polyethylene glycol for use as a processing additive, since fluorinated polymer does not swell in polyethylene glycol and does not dissolve in water. The use of mixtures of polyethylene glycol with chemical compounds containing boron and oxygen as a complex additive for improving the molding of a thermoplastic polymer material is known, however, the technical advantage of using such mixtures in combination with other thickeners, in particular with silanol, has not been shown. The use of mixtures of polyethylene glycol with chemical compounds containing phosphorus and oxygen as a complex additive to improve the molding of a thermoplastic polymer material was not known. Other thickeners for polyesters and for polyethylene glycols, for example metal stearates, are known from the technical literature, but it is not known to use compositions containing polyethylene glycol and metal stearate as a complex processing additive. The proposed technical solution also relates to the use of a combination of several proposed thickeners as a polyester thickener.

Thus, the proposed invention is new and meets the requirements of an inventive step. Examples of the implementation of the technical proposal indicate industrial applicability.

Within the scope of the claimed invention, modifications obvious to specialists are possible of the claimed invention. Therefore, it should be understood that all implementation examples, in particular molding conditions, chemicals, temperatures, etc., are intended to provide a general illustration of the invention, and should not be construed as an unjustified limitation of the protection limits of the claimed invention.

Since the use of borates and boric acids as a thickener and mixtures based on polyols and silanols with borates as a processing aid are known from the prototype of the claimed invention [481, it seems advisable not to indicate in the Formula of the invention, but to leave in the description of the invention recommendations for compositions based on these borates and mixtures of borates with other thickeners. Similarly, it seems appropriate not to indicate in the Formula, but to leave in the description of the invention recommendations for compositions using mixtures of polyols with silanol and borates, which correspond to the particular case of the implementation of the prototype of the claimed invention.

It seems advisable not to indicate in the claims, but to leave in the description of the invention the use of water-soluble, but insoluble in polyesters, high molecular weight compounds as thickeners, since the preparation of mixtures using solvents is not economically feasible. It seems advisable not to indicate in the claims, but to leave in the description of the invention the use of carboxylic acid and alkali metal salts as thickeners, since the introduction of alkali metals in the composition of the polymer material can reduce its resistance to ultraviolet radiation and heat, which is usually undesirable.

It seems appropriate to limit the choice of mineral powder in the Formula of the invention to highly dispersed oxides of silicon and titanium, since these mineral powders are cheap and affordable, and the use of other mineral powders, such as delaminated clay, as a thickener appears to be economically disadvantageous. It seems advisable not to indicate in the claims, but to leave in the description of the invention the use of polyisocyanates as thickeners. Polyisocyanates are not recommended for contact with food and the human body. Although the reaction of polyisocyanates with polyols reduces their toxicity to an acceptable level, it cannot be ruled out that toxic gases will be released during the formation of the polymer material, which is undesirable.

Specialists in the field of polymers and rheology understand that polyesoluble polymers with a molecular weight of from 100,000 to 20,000,000 daltons can be used as thickeners of polyesters and if polyethylene oxide with a molecular weight of 5,000,000 daltons shows good results, then the same improvement will be observed for all soluble in polyesters of polymers and any molecular weight of additives from the specified range.

Specialists in hydromechanics and rheology understand that highly dispersed powders of silicon and titanium oxides with particle sizes from 1 to 1000 nanometers can be used as thickeners for polymer liquids and, if in the implementation examples, it is shown that if powders of silicon and titanium oxides with particle sizes of about 10 nanometers show good results, then other highly dispersed powders of silicon and titanium oxides with particle sizes from the specified range can be used to prepare the claimed polymer compositions wow stuff.

Specialists in the field of chemistry and polymers understand that if phosphoric acid, organophosphates and organophosphites. used in the examples of the implementation of the claimed invention, show good results, then other chemical compounds containing phosphorus and oxygen from the following group: phosphorus oxides in oxidation states of phosphorus +3 or +5, oxygen phosphorus acids in oxidation states of phosphorus +3 or +5, esters of said phosphorus acids, acid salts of said phosphorus acids, and also mixtures of said chemical compounds can be used to prepare the claimed compositions of the polymer material.

It should be clear that all documents cited in the description of the invention, as well as citations from any of the specified document, cannot limit the scope of protection of the claimed invention. If the terms do not coincide in the present description and in the cited documents, it is the present description of the invention that sets the meaning and definition of the terms used.

Claims (8)

1. Thermoplastic polymer material, including an organic thermoplastic polymer as the main component and a complex additive to improve molding, in the following ratio of components, wt.%:
complex supplement 0.02-1 thermoplastic polymer rest,
in this case, as a complex additive, a composition is used containing one or more polyesters selected from the group of simple and complex, linear and branched aliphatic polyesters with a melting point in the range from 35 to 120 ° C and with a molecular weight of from 1000 to 10000 Yes, and one or several thickeners, in the following ratio of components, wt.%:
thickeners 0.01-20 polyesters rest,
and thickeners are selected from the following group:
soluble in polyesters polymers with a molecular weight of from 100,000 to 20,000,000 Yes,
fine powders of silicon and titanium oxides with particle sizes from 1 to 1000 nm,
chemical compounds containing phosphorus and oxygen from the following group: phosphorus oxides in the oxidation states of phosphorus +3 or +5, oxygen phosphorus acids in the oxidation states of phosphorus +3 or +5, esters of these phosphorus acids, acid salts of these phosphorus acids, and mixtures of these chemical compounds. 2. The thermoplastic polymer material according to claim 1, characterized in that the polyesters use polyhydroxy compounds that are selected from the group of polyethylene glycols with a molecular weight of from 1000 to 10000 Da, or a mixture of these polyethylene glycols with polyhydric alcohols, soluble in polyethylene glycols, or copolymers of polyhydric alcohols and polyethylene glycols, where the weight content of polyhydric alcohols in a mixture or in a copolymer with polyethylene glycols does not exceed 20%. 3. The thermoplastic polymer material according to claim 1, characterized in that the organic thermoplastic polymer is selected from the group of polyolefins or a mixture of polyolefins with a narrow molecular weight distribution. 4. The thermoplastic polymer material according to claim 2, characterized in that the organic thermoplastic polymer is selected from the group of polyolefins or a mixture of polyolefins with a narrow molecular weight distribution. 5. The thermoplastic polymer material according to claim 1, characterized in that the organic thermoplastic polymer is selected from the group of polyethylene or a mixture of polyethylene with a narrow molecular weight distribution. 6. The thermoplastic polymer material according to claim 2, characterized in that the organic thermoplastic polymer is selected from the group of polyethylene or a mixture of polyethylene with a narrow molecular weight distribution. 7. Thermoplastic polymer material according to claims 1 to 6, characterized in that as a thickener or one of the thickeners containing phosphorus and oxygen, organic phosphates or phosphites are used, which are selected from esters of phosphoric or phosphorous acid, as well as mixtures and copolymers these esters. 8. Thermoplastic polymer material according to claims 2, 4, 6, characterized in that polyethylene oxide with a molecular weight of from 100,000 to 20,000,000 Da is used as a thickener or one of the thickeners.

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