Flexible and elastic chemical composition based on poly (vinylidene fluoride) and the method of production thereof
(57) Abstract:The invention relates to compositions based on fluorinated polymers, and method of production thereof. Flexible and elastic composition comprises at least one homopolymer (a) vinylidenefluoride (VF2) or copolymer (a) vinylidenefluoride and at least one other fluorine-containing monomer that can be copolymerized with vinylidenefluoride, in which 100 weight.h. vinylidenefluoride mentioned monomer present in an amount of from 0 to 30 weight. including at least one elastomer, at least one plasticizer C. this composition comprises on a 100 weight.h. component And 0.5 to 10 weight.h. component b and from 0.5 to 10 weight.h. the component With the additional condition that the sum of b and C is from 1 to 10.5 weight.h. Plasticizer selected from ester plasticizer and sulfonamida. The invention can be used for the manufacture of materials exposed to mechanical stresses, sealing membranes, various products for chemical industries. 2 C. and 7 C.p. f-crystals, 5 PL. The invention relates to the field of polymers. The object of the invention are compositions based on fluorinated polymers, as well as the way the particular as good thermal stability, high chemical resistance, in particular, with respect to solvents, resistance against a variety of atmospheric effects and the effects of various radiations, in particular the resistance to UV radiation, the proof of these polymers to gases and liquids, as well as good electrical insulation properties. Such polymers are used, in particular, for the manufacture of pipes intended for the transportation of hydrocarbons extracted from oil fields located under the land (on-shore), and under the bottom of the sea (offshore). Extracted from these deposits of hydrocarbons in some cases have to be transported at relatively high temperatures (about 135oC) and high pressure (which can be as high as 70 MPa). The operation of oil or gas installations in such circumstances raises problems of thermal and chemical resistance used in the technological process materials, as well as sufficient mechanical strength. To these above-mentioned requirements can be added and other requirements associated with the use of such pipes before or after their panovka (i.e. unwinding from the spools and winding coils) these pipes may be exposed to shock and efforts bending, they also must be able to stand, often at very low temperatures (for example, at temperatures of about -35oC).In order to try to meet these requirements, both in the short and in the long term, have been proposed various types of materials containing, typically, one or more metal elements, providing the desired mechanical strength, for example twisted in a spiral steel tape, as well as various layers based on polymer compositions, providing, in particular, the required tightness and thermal insulation. These compositions, often based on fluorinated polymers, in particular on the basis of semi-crystalline poly (vinylidene fluoride) (PVDF), in some cases, subjected to forced plasticization to eliminate the possible lack of flexibility, poor deformability on the threshold of fluidity and lack of elasticity. The disadvantage of this technical solution is more or less rapid retrieval of this material is introduced into it plasticizers the flow of hydrocarbons, which leads to a gradual loss of the material properties that were given to him of the relevant platifina is a journey of this length of service life of parts, based on these chemical compounds.In order to resolve some of these problems, plasticized, if necessary, the fluorine-containing polymers, substituted polymeric composition containing a homopolymer PVDF, thermoplastic copolymer vinylidenefluoride (VF2) and at least one other fluorine-containing monomer (see document EP 608939 and EP 608940), and plasticizer (see document EP 608939). However, strict and precise control of a given morphological structure of such mixtures requires the use of complex and expensive equipment, which makes these technical solutions are hard to obtain. On the other hand, it is noted that mixtures of this kind have limited elasticity at low temperatures and poor resistance to swelling, for example, in contact with the hydrocarbon and chemical resistance, inferior chemical resistance of the PVDF and subjected to effect extraction of the plasticizer, if present in the composition, upon contact with certain chemicals.Efforts were also made of the incorporation into the polymer type PVDF particles of the elastomer (see , for example, document FR 2592655 and FR 2618791) to absorb uglevodorodami mass of the mixture. Mixtures of this kind are characterized by high elasticity compared to the pure polymer type PVDF, but its flexibility is insufficient to consider some applications of this material, in particular for use in devices for transportation and/or storage of hydrocarbons, because the mixture of this type is not sufficiently flexible in the case when it is not in direct contact with hydrocarbons. In the document FR 2592655 described mixture containing optionally a plasticizer comprising at least 10% of the total weight of the mixture, which, although having at the same time the necessary flexibility and resistance to shock, sooner or later allow the selection of the plasticizer.In the application for the European patent EP 0714944 described composition containing a matrix of PVDF, which are scattered small inclusions of vulcanized elastomers, and softened, if necessary, by the introduction of plasticizers. These compositions are characterized by a very high multiaxial impact strength, however, the number of these elastomers on the level of 26.6 or 50 weight. hours at 100 weight. including polymer PVDF 1000 (see the following examples 6 and 11) is so significant that such compositions in the morning the positions is their high permeability under pressure, and poor resistance to rapid decompression of hot gases under pressure ("blistering").In the present invention seeks to overcome the above-mentioned problems, therefore, an object of this invention is flexible and elastic composition containing:
at least one homopolymer (a) vinylidenefluoride (VF2) or copolymer (A) VF2 and at least one other monomer that can be copolymerized with VF2, in which 100 weight. h VF2 mentioned monomer present in an amount of from 0 to 30 weight. h,
at least one elastomer IN,
at least one plasticizer,
characterized in that, on the one hand, it contains 100 weight. including polymer And from 0.5 to 10 weight. including elastomer and from 0.5 to 10 weight. including plasticizer With the additional condition that the total content of the elastomer and the plasticizer is from 1 to 10.5 weight. o'clock, and, on the other hand, the fact that the said homopolymer or copolymer of vinylidenefluoride And choose so that he possessed the flow index, measured in accordance with ISO standard 1133 at a temperature of 230oWith under a load of 5 kg, of less than 5 g/10 min, and the critical Gcat the intersection of the shear moduli in the molten state by G:
- elongation at the threshold of turnover at more than 11%,
- elongation at break r exceeds 200%,
- measured in accordance with ISO norm 180-1982 impact resistance at a temperature of 23oWith exceeds 50 kJ/m2and impact resistance at a temperature of -30oWith exceeds 10 kJ/m2,
- resistance to rupture in bending on coated metal tape exceeds 50%,
- weight loss p in the air at a temperature of 150oWith in one month does not exceed 8% and change of mass of p in the oil environment (ravnovyesnaya mixture of cyclohexane, isooctane and xylene) at a temperature of 150oWith in one month is not negative (that is, the composition does not lose its weight in oil environment).Critical module Gwithis determined at a temperature of 190oWith using a dynamic mechanical spectrometer, such as a spectrometer type Rheometrics RMS 800, using a viscometer of the type of plane-plane diameter 25 mmPreferably the relative amount specified other monomer is from 0 to 5 weight parts.Preferably, the specified another monomer preditor In the present in the composition in relative amounts of from 0.5 to 5 weight. hours at 100 weight. including polymer A.In a preferred embodiment of the invention the plasticizer With presents in the composition in relative amounts of from 0.5 to 5 weight parts per 100 weight parts of polymer A.Fluorine-containing polymers And included in the compositions according to the invention, chosen among the homopolymers or copolymers of VF2 because of their special chemical inertness in the presence of crude oil or natural gas coming directly from the fields, and their stability at high temperatures.Preferably, the composition according to the invention contain 100 weight parts of homopolymer of vinylidenefluoride, and 2.1 parts by weight of elastomer In and 3.2 parts by weight of plasticizer, and said homopolymer is chosen so that the flow index MFI, measured at a temperature of 230oWith, was 0.7, and the critical module Gcmeasured at a temperature of 190oWith was 20 kPa.In the preferred embodiment, these compositions according to the invention, the elastomer is In an acrylic elastomer and plasticizer is dibutylsebacate.Suitable for use under the proposed isostasy elastomers or rubbers, natural or synthetic, are determined by the standard ASTM (see Special Technical Bulletin No. 184) as materials that can be stretched at room temperature to double their original length and which after removal of this tensile stress, impacted material within 5 minutes, up to 10% restore its original length after the same period of time. Thermoplastic elastomers (TPE) provide elongation at the threshold of the yield strength in excess of 15%. These thermoplastic elastomers are properties between thermoplastic resins, easy to use and allows a variety of uses, but with properties, limited by temperature or in the dynamic area, and the elastomer with excellent elastic properties, but the use of which is sufficiently severe, complex and in some cases polluting the environment. Structure of thermoplastic elastomers always contains two incompatible phases, one of these phases combines thermoplastic segments, dispersed in the elastomer phase. Usually there are 5 categories of thermoplastic elastomers (TPE):
- polyolefin thermoplastic, elastometric more than 60% polypropylene, and mixtures, in which the elastomer phase is predominant (>70%), and this phase can be both structured and not structured;
- block copolymers based on polystyrene, in which the hard phase is formed by segments of polystyrene and flexible phase can be formed, for example, segments of polybutadiene (SBS), polyisoprene (SIS) or polyethylenimine (SEBS);
- block copolymers based on polyurethane (TPU), which can be obtained from the joint reaction of diol with a high molecular weight, which forms a flexible and amenable to crystallization segment of the polymer chain of thermoplastic elastomer TPE, with a diisocyanate and diola low molecular weight, which constitute the hard segment of the polymer chain;
- block copolymers based on polyester, for example, obtained by copolymerization of polybutylene (RHT) or polyethylene terephthalate (PET), which form a rigid and crystalline segments, and glycol or low molecular weight (butanediol, diethylene glycol), which together with polyalkylene ether glycol forms a flexible and amenable to crystallization segment;
- block copolymers based on polyamide, in which the hard segments are formed of polyamide (PA), and the Rami, and complex polyetherimide.Elastomers and TRE preferably can be selected from among natural rubber, polyurethanes, copolymers of maleic ethylene-propylenediene (EPDM) copolymers Acrylonitrile-butadiene-styrene (ABS), copolymers of methacrylate methylbutadiene-styrene (MBS), block copolymers based on polyamide (e.g., simple, complex, and a mixture of simple and complex polyetherimide), copolymers of ethylene-carbon monoxide, acrylic rubbers, in particular particles of core-shell with poly (acrylic surface layer, SBS, SIS, copolymers of ethylenediurea, ethylene-ethyl acetate, ethylene-vinyl acetate, and their terpolymers.Preferably the elastomer in choosing among the copolymers of methyl methacrylate-butadiene-styrene (MBS) and acrylic rubber.In a preferred embodiment, the acrylic rubber is used in the form of particles of core-shell with poly (acrylic surface.Plasticizers can be selected from among commonly used plasticizers, in particular among those described in documents US 3541039 and US 4584215. In a preferred embodiment, the plasticizer is selected among dibutylsebacate and N-n-butylsulfonyl.In addition to the above-described components a, b and the ate, and/or dyes and/or pigments, organic or mineral, macromolecular or not.As non-limiting examples of fillers include mica, alumina, talc, gas, carbon black, glass fiber, carbon fiber, macromolecular compounds.As non-limiting examples of additives can be called agents, anti-UV, agents for imparting fire resistance, thermal stabilizers, as well as agents of transformation or "processing aids".The total content of these various additives and fillers is less than 20% of the total weight of a+b+C.In a preferred embodiment, the receiving of the compositions according to the invention is carried out by mixing in the molten state of the components a, b and C.The composition according to the invention can be prepared by mixing in the molten state of homopolymer or copolymer of vinylidene And with one or more elastomers, originally presented in the form of powder or granules in an extruder, a roll mixer, or in any other suitable apparatus for mixing.You can also mix a homopolymer or copolymer of wines is tx2">One or more plasticizers, and used, if necessary, additives may be introduced into the structure of the considered compositions or process of mixing components a and b, or may be pre-mixed with one or other of these components before they are mixed among themselves, or can be introduced into the mixture and after mixing them using the above mentioned technologies mixing.The composition of the invention can be used for the manufacture of materials exposed to mechanical stresses under conditions of high and/or low temperatures, contact with particularly aggressive environments, such as hydrocarbons, strong acids, solvents, mineral and organic bases, when these materials are particularly required robust implementation is satisfactory properties of flexibility and elasticity.As mentioned above, the composition according to the invention is particularly well adapted for making sealing membranes flexible metal piping designed to extract fields and/or for transportation of natural gas and hydrocarbons in the oil and gas industrial is applied by extrusion or co-extrusion. In so manufactured pipe and then insert the corresponding flexible metal conduit. Such sealing membrane can also be formed directly on the flexible metal tubing using conventional technologies to create the pipe exterior coating.The composition according to the invention can also be used in multilayer sealing membranes such as those described, for example, in U.S. patent 5601893.The composition of the invention is also well adapted for manufacture by extrusion of various products for chemical production, in particular in the form of hoses and pipes, and also for producing the relevant products in the field of construction and urban development, for example the insulating sheaths of cables, ropes and strands, as well as single-layer and multilayer films and sheets for any other industrial needs.The composition of the invention can also be used for the manufacture of insulating sheaths for electrical wires, cables, strands and stretch marks such as those described in applications for European patents EP 671502 and EP 671746.EXAMPLES
Using a single-screw ECG compression 3,5), adjusted to a temperature of 220oWith, ekstragiruyut composition (Ai Bj Ck x) containing at least 7 fluorine-containing polymers A1 to A7, one of the 4 elastomers from B1 to B4 and one of the 2 plasticizers C1 and C2. In accordance with the selected proportions of the various components of the respective compositions indicated positions from before .
Table 1 shows a flow index in the hot condition of fluorine-containing polymers Ai, which are homopolymers or copolymers of vinylidenefluoride VF2, as well as their critical module. The table below shows flow index MFI measured in accordance with ISO standard 1133 at a temperature of 230oWith under a load of 5 kg Critical module Gcdetermined at a temperature of 190oWith using a dynamic mechanical spectrometer, such as a spectrometer type Rheometrics RMS 800, and viscometer type plane-plane diameter 25 mmTable 2 shows the chemical nature of the brand names and suppliers of elastomers Bj.Table 3 shows the chemical nature, as well as the family to which they belong plasticizers Ck.Table 4 shows the weight proportions of the various components of rassmatrivaemye using classical methods of radical polymerization in emulsion or in suspension type those described in the application for the European patent EP 709429 and patents France FR 2286153 and FR 2610325. They can also be obtained in solution or in bulk.More specifically, used in this case, the elastomer B1 obtained by radical polymerization in the aqueous phase of acrylic monomers in accordance with U.S. patent 3264373 or 3562235.Elastomer B2 obtained by radical polymerization in the aqueous phase and consists of the predominant phase formed by a copolymer of methyl methacrylate, butadiene and styrene (MBS) and phase-based polyacrylate.Elastomer B3 consists of two interpenetrating phases of polymers, one of which is a polymer-based polyacrylate, and the other is an organosilicon polymer.Elastomer B4 obtained by radical polymerization in emulsion. This elastomer is a copolymer of butadiene and partially hydrogenated to increase its thermal stability of Acrylonitrile.Testing was performed against the above compositions by measuring the tensile strength, impact strength IZOD, tensile bending covered this song metal line tension was measured on the plates with a thickness of 0.7 mm, prepared from the above extruded compositions and molded at a temperature of 205oWith tiled press. Samples for tensile tests of type ASTM D 1708 were cut using a special matrix of these plates. Elongation under tension (i.e. deformation on the threshold yield stress y and deformation before fracture r) was measured in accordance with standard ASTM D 638 at normal ambient temperatures.Impact strength IZOD with notch groove (measured at a temperature of 23oWith and at a temperature of -30oC) was investigated on the samples extruded at a temperature of 230oWith and having dimensions of 80 x 10 x 4 mm, and the recess grooves and the test Protocol was in accordance with the norm ISO 180-1982.Bending strength carried out on a metal tape coated from the tested compositions were evaluated under normal ambient temperature on flexible metal construction (metal tape with the edge bent in such a way as to receive the outer diameter of the bend, equal to 29 mm), having a coating of compositions considered here, extruded using a right-angle head. This coating has an average of ITA a shell pipe is mounted on two fixed support, spaced from each other at a distance of 250 mm By means of a bending roller with a diameter of 80 mm exercise pressure on the pipe at the same distance from its points of support, creating a pressure sufficient to cause bending of the pipe until its rupture. This measures the depth of the above-mentioned roller, which indicates the ability of this flexible tube to deform. The ratio of the depth of immersion of the above-mentioned roller, measured at break that pipe, to the maximum depth of dives recorded at the level of 160 mm, corresponds to the bending strength with the said coating of metal tape.Thermal and chemical resistance is evaluated by measuring the rate of change of weight R extruded sample of this composition to a thickness of 3 mm and a weight of 5 g and identical to the sample, placed for 1 month at a temperature of 150oWith in a given environment [air or oil (1/3 of the volume of cyclohexane, 1/3 of isooctane and 1/3 xylene)], which are also measured elongation tensile (i.e., the parameters y and r). The sign "-" (minus) corresponds to the weight loss.Chemical resistance is evaluated by measuring weight changes R extruded between 7 days at a temperature of 50oWith the solution of hydrochloric acid Hcl with a concentration of 37% by weight, followed by rinsing in distilled water and drying for 24 hours at a temperature of 150oC. the Sign "-" (minus) corresponds to the weight loss.All results are summarized in the following table 5.The preferred composition for the manufacture of pipelines designed to transport liquid hydrocarbons, is, as it follows from the results in table 5, the composition is 5: A4 B1 C1 .I 1. Flexible and elastic composition comprising at least one homopolymer (a) vinylidenefluoride (VF2) or copolymer (a) vinylidenefluoride and at least one other fluorine-containing monomer that can be copolymerized with vinylidenefluoride, in which 100 weight.h. vinylidenefluoride mentioned monomer present in an amount of from 0 to 30 weight.h., at least one elastomer, at least one plasticizer, characterized in that, on the one hand, the composition comprises on a 100 weight.h. component And 0.5 to 10 weight.h. component b and from 0.5 to 10 weight.h. the component With the additional condition that the sum of the components b and C is from 1 to 10.5 weight.h., on the other hand, the fact that the homopolymer is accordance with ISO standard 1133 at 230oWith under a load of 5 kg was less than 5 g/10 min and a critical module Gwithat the intersection of the shear moduli in the molten state G' and G", measured at 190oWith, ranged from 5 to 22 kPa, and a plasticizer selected from ester plasticizer and sulfonamida, and this composition has the following properties: elongation at the threshold of turnoveryexceeds 11%, the elongation before rupturerexceeds 200%, measured in accordance with ISO norm 180-1982 impact strength at 23oWith more than 50 kJ/m2and impact strength at -30oWith is more than 10 kJ/m2, tensile strength in bending on coated metal tape exceeds 50%, the loss of mass of p in the air at 150oWith in one month does not exceed 8% and change of mass of p in the environment of oil (ravnovyesnaya mixture of cyclohexane, isooctane and xylene) at 150oWith in one month is not negative.2. The composition according to p. 1, characterized in that the said other monomer is present in an amount of from 0 to 5 weight.h.3. Composition according to any one of paragraphs.1 and 2, characterized in that the component In a relative amount of from 0.5 to 5 weight is Alceste from 0.5 to 5 weight.h.5. Composition according to one of paragraphs.1-4, characterized in that thermoplastic elastomer In choosing among the copolymers, methyl methacrylate-butadiene-styrene (BS) and acrylic rubber.6. The composition according to p. 5, characterized in that the acrylic rubber in the form of particles such as core-shell (core-shell) with polyacrylic surface layer.7. Composition according to any one of paragraphs.1-6, characterized in that it contains 100 weight.h. homopolymer of vinylidenefluoride, 2.1 weight.h. component and 3.2 In weight. including component, and a homopolymer chosen so that the flow index FI measured at 230oWith, was 0.7, and the critical module Gwithmeasured at 190oWith is 20 kPa.8. The composition according to p. 7, wherein the component is an acrylic elastomer, and the component is dibutylsebacate.9. The method of obtaining the composition according to one of paragraphs.1-8 by mixing in the molten state of at least one homopolymer or copolymer vinylidenefluoride (A) at least one elastomer (b) and at least one plasticizer (S), as defined in paragraph 1.
FIELD: polymer materials.
SUBSTANCE: invention provides elastic and resilient composition containing (A) at least one homopolymer of vinylidene fluoride or copolymer of vinylidene fluoride with at least one other monomer capable of being copolymerized with vinylidene fluoride wherein proportion of this other monomer ranges between 0 and 30 wt parts per 100 wt parts vinylidene fluoride, (B) at least one fluorinated elastomer, which is copolymer of vinylidene fluoride and at least one other fluorinated monomer, and optionally (C) plasticizer. Composition is characterized by that, on the one side, it contains 0.5 to 10 wt parts B and 0 to 10 wt parts C per 100 wt parts A, provided that B+C = 0.5 tp 10.5 wt parts, and, on the other side, such vinylidene fluoride homopolymer or copolymer is chosen in such a way that it has coefficient of fluidity below 5 g/10 min, as measured according to standard ISO 1133 at 230°C under load 5 kg, and critical modulus G ranging between to 5and 22 kPa, as measured in intersection of shear moduli G' and G" in molten state at 190°C.
EFFECT: essentially increased stability of composition in air and in crude oil.
7 cl, 6 tbl, 12 ex
FIELD: polymer materials.
SUBSTANCE: composition contains, wt %: vinylidene fluoride 20-40, methyl methacrylate homopolymer or copolymer, acryl elastomer 5-18, and UV-absorbing substance 1-4. Invention also discloses jointly extruded films (options) and substrates covered by these films. Invention enables preparing composition with not rising UV-absorbing substances and manufacturing films showing high mechanical strength and providing high-quality adhesion to substrate while being resistant to radiation.
EFFECT: improved consumer's properties of films.
14 cl, 7 ex
FIELD: polymer materials.
SUBSTANCE: invention relates to polymer mixture for use in membrane manufacture. Mixture contains (i) at least one acrylic polymer or at least one acrylic polymer and at least one vinyl polymer, which polymers comprise at least one ionic or ionizable group, in particular sulfurized group, and (ii) at least one thermoplastic fluoropolymer, provided that components (i) and (ii) differ from each other. Invention also related to polymeric ionic membrane, membrane electrode complex, fuel cell, battery, and to a polymer mixture and composition preparation process.
EFFECT: enabled production of fluoropolymer uniformly mixing with other polymers, enabled manufacture of membrane directly from aqueous fluoropolymer dispersions, and increased chemical resistance and mechanical strength of membranes.
25 cl, 5 tbl, 13 ex
FIELD: polymer materials.
SUBSTANCE: invention provides polymer composition containing one or several halogenated thermoplastic polymers and being characterized by RMFI between 1.1 and 6, where RMFI is ratio of melt flow indexes MFI8/2 and MFI0.3/1 measured in accordance with standard ASTM D1238. Invention also discloses preparation method and use for these compositions.
EFFECT: enabled preparation of compositions exhibiting a rheological property (stretching viscosity), which is characterized by elevated resistance to deformation during foaming.
14 cl, 2 dwg, 3 tbl, 8 ex
SUBSTANCE: invention proposes composition polymeric material of tribotechnical designation based on polytetrafluoroethylene, coke and activated magnesium spinel and can be used in machine and mechanisms heavy-loaded friction units. The composition polymeric material comprises the following components, wt.-%: coke, 13.0-14.5; magnesium spinel activated in planetary mill AGO-2 for 2 min, 0.5-2, and polytetrafluoroethylene, the balance. Using the invention allows enhancing longevity and working ability of friction units based on high abrasion resistance, low friction coefficient that are determined by the composition structure.
EFFECT: improved and valuable properties of material.
FIELD: chemistry; rubber industry.
SUBSTANCE: invention pertains to rubber mixtures based on fluoroprene, used for making rubber goods, which can work in conditions affected by fuel and used in the motor-car industry. The rubber mixture consists of a vinylidene fluoride terpolymer and tetrafluoroethylene, magnesium oxide, calcium hydroxide, technical carbon T-900, di-(4hydroxyphenyl)dimethylmethane, pentaerythritol tetrastearate, dibutyl sebacate and a catalyst. The catalyst used is in the form of guanidine quaternary salts, and more specifically, guanidine bromide or chloride. The catalyst is a compound obtained from interaction of phenyl-bi-guanidine hydrochloride or hydrobromide with lower bromide or ethyl chloride, with molar ratio of 1:7 in the presence of a base. The catalyst is taken in percentage mass ratios of 0.5-0.7% at 100% mass of terpolymer.
EFFECT: increased rate of vulcanisation of rubber mixtures; wide range of catalysts for fluoroprene.
3 tbl, 2 ex
SUBSTANCE: invention pertains to compositions of high-molecular compounds, in particular, to compositions of homopolymers of vinyliden fluoride. Description is given of the composition based on polyvinyliden fluoride, containing polyvinyliden fluoride, as well as an elastomer, in the form of butadiene-styrene thermoplastic elastomer, in quantity of 15-30% of the mass, and extra 3-8% mass of high pressure dispersed polyethylene, irradiated in an oxygen containing medium, to an absorbed dose of 100-400 kGY.
EFFECT: increased tribotechnica characteristics, reduction of frictional coefficient and increased wear resistance of the composition based on polyvinyliden fluoride.
1 cl, 2 tbl, 7 ex
SUBSTANCE: described is a polymer composition formed from molten mass, containing: (a) non-fluorinated polymer formed from molten mass; and (b) fluoropolymer obtained from copolymerisation (1) from 20% to 30% of total weight of vinylidene fluoride; (2) one or more fluorinated monomers which are not vinylidene fluoride, and (3) one or more modifiers which are selected from (i) olefins containing a bromine or iodine atom bonded to the carbon atom of the olefin double bond, (ii) olefins of formula (IV): Xa 2C = CXa-Rf-(Xb)r (IV), where each Xa can independently represent hydrogen, fluorine, chlorine, Rf represents a perfluoroalkylene group, perfluorooxyalkylene group or perfluoropolyester group; Xb represents Br or I or r equals 1, 2 or 3, and (iii) a mixture of these substances; also content of one or more modifiers is not more than 1 wt %, is sufficient for formation of a long, branched chain of a fluoropolymer without formation of gel, where the composition contains 0.005-50 wt % fluoropolymer, the non-fluorinated polymer being that, which does not contain fluorine atoms or contains fluorine atoms with ratio of fluorine atoms to carbon atoms less than 1:1, the fluoropolymer has a fluorinated chain in which the ratio of fluorine atoms to carbon atoms is at least equal to 1:1. Also described is a polymer fusible additive composition for use as an additive during extrusion of non-fluorinated polymer.
EFFECT: increased effectiveness of the composition.
10 cl, 12 ex, 8 tbl
SUBSTANCE: rubber mixture contains the following in pts. wt: copolymer of vinylidene fluoride and hexafluoropropylene SKF-26 63-69, low-molecular weight copolymer SKF-26 ONM 31-37, barite 20-35, vulcafluoro F 1.5-3.0, magnesium oxide 3-6, calcium hydroxide 5-7, triethylbenzylammonium chloride 0.2-0.5, modifier of adhesion strength of vulcanised rubber to metal - cobalt salt of 2-sulfobenzoic acid 0.5-2.0.
EFFECT: high adhesion strength of vulcanised rubber to metal.
SUBSTANCE: composition contains the following components, wt %: pyro-packed thermally expanded graphite 10-55 (content of pyrocarbon equals 4-5% of the weight of graphite), fluoro-polymer F42, acetone - the rest. The invention discloses a coating method.
EFFECT: improved electroconductive properties, corrosion resistance and strength of articles made from said composition.
3 cl, 1 tbl, 3 ex