FR2466481A2 - Polystyrene-di:organo:polysiloxane elastomer - used for moulded goods, coatings, fibres, selectively permeable membranes and prostheses - Google Patents

Abstract

Parent patent claims thermoplastic elastomers having units of formula (-CH2CH2SiR2(C(C6H5)2-CH2)a (C(G)R'-CH2)n-A-(CH2-C(G)R')n (CH2-C(C6H5)2) SiR2CH2CH2SiR2(OSiR2)m, where R is (m)ethyl, n-propyl, phenyl or 3,3,3-trifluoropropyl; R' are H or methyl; A is a 6-45C naphthalene, biphenylene, alkylene or polyalkylene gp., opt. substd. by aromatic rings; G is (I) C6(H)5-b(CH3)b, where b is 0-3, or (II) C6H4N(CH3)2; a is 0 or 1; n and n' are 20-500; and m is 1-1500. Polystyrenic polydiorganopolysiloxanes have the above formula, in which G is C6H4R"c(SiR3), where R" is H, methyl or SiR3; and c is 0-2, are novel. The copolymers can be used for joints, profiles, insulating or protective coatings, and fibres. The gas permeability is good and the copolymers can be used for selectively permeable membranes, e.g. for artificial lungs, or for sepn. of gaseous mixts. They are physiologically inert and can be used for prostheses. In the new elastomers, some of the G gps. may be of formulae (I) or (II). The mol. wt. is 20,000-2,000,000. Pref., the copolymer contains 30-85wt.% of the siloxane units. The claimed prepn. involves (a) anionic polymerisation of C(G)R'=CH2, using AM2, where M is K, Na or Li as initiator, to give a living polymer, (b) reaction of the mixt. from (a) with diphenylethylene, to give a second living polymer, (c) reaction of the polymer from (b) with (CH2=CH)-R2SiCl, to give a polystyrenic difunctional polymer, and (d) reaction of this difunctional polymer with HSiR2(OSiR2)mH.

Description

 The present invention relates to polysomeric thermoplastic elastomeres comprising a succession of units, each of which is formed of a rigid polystyrenic block and a diorganopolysiloxane flexible block connected to each other by a non-hydrolyzable bond.

dans laquelle
- Les symboles R, identiques ou différents, représentent des radicaux méthyles, éthyles, n-propyles, phényles, trifluoro-3,3,3 propyles.In the French patent application 78/26245, thermoplastic elastomers have been described characterized in that they are formed of a succession of units corresponding to the general formula F

in which
The symbols R, identical or different, represent methyl, ethyl, n-propyl, phenyl or 3,3,3-trifluoropropyl radicals.

 - The symbols R ', identical, represent hydrogen atoms, methyl radicals.

 the symbol A represents a divalent hydrocarbon radical, without aliphatic unsaturation, having from 6 to 45 carbon atoms and chosen from naphthalene, biphenylenes, alkylene and polyalkylene radicals optionally substituted by aromatic rings.

 - The symbols G, identical, represent radicals of formula - C6 (H) b (CH3) b in which the symbol -b represents 0, 1, 2 or 3, radicals of formula -C6H4N (CH3) 2.

 the symbols a identical, represent zero or 1.

 the symbols n and n ', which are identical or different, represent any number whose sum ranges from 20 to 500.

 the symbol m represents any number ranging from 1500 to 1500.

- les symboles G représentent des radicaux phényles et, uniquement lorsque les symboles R' représentent des atomes d'hydrogène, des radicaux de formule

des radicaux de formule

It was furthermore specified in the French patent application 78/26 245 that the various symbols appearing in the formula
F could take the following preferred meanings
the symbols R represent methyl radicals
the symbol A represents the naphthylene-1,5 radical, the tetramer of α-methylstyrene, the radicals of formula

the symbols G represent phenyl radicals and, only when the R 'symbols represent hydrogen atoms, radicals of formula

radicals of formula

the symbols a represent zero
the symbols n and n 'represent arbitrary numbers whose sum ranges from 30 to 400.

 the symbol m represents any number between 10 and 1200.

dans laquelle
- les symboles R identiques ou différents représentent des radicaux méthyles, éthyles, n-propyles, phényles, trifluoro-3,3,3 propyles.It has now been found and this is the object of this certificate of addition of new thermoplastic elastomers comprising a succession of silylated and diorganopolysiloxane polystyrene units and having the general average formula (F ')

in which
the identical or different R symbols represent methyl, ethyl, n-propyl, phenyl or 3,3,3-trifluoropropyl radicals.

the identical or different symbols R 'represent hydrogen atoms or methyl radicals
the symbol A represents a divalent hydrocarbon radical, without ethylenic unsaturation having from 6 to 45 carbon atoms, and chosen from naphthylene, biphenylenes, alkylene or polyalkylene radicals optionally substituted with aromatic rings.

et dans laquelle
- R" représente un atome d'hydrogène, un radical méthyle, ou un groupement SiR3
- c représente un nombre entier égal a 0,1 ou 2.the identical or different symbols G 'represent silylated aromatic radicals having the formula

and in which
R "represents a hydrogen atom, a methyl radical or an SiR3 group
c represents an integer equal to 0.1 or 2.

 - R has the meaning previously given.

The symbols G 'may optionally be partly replaced by identical or different radicals G and representing radicals of formula C6 (H) b (CH3) b in which the symbol b represents 0, 1, 2 or 3, or radicals of formula -C6H4-N (CH3) 2
the identical symbols a represent zero or 1
the symbols n and n ', which are identical or different, represent arbitrary numbers whose sum is between 20 and 500.

 the symbol m represents any number between 1 and 1500.

As a preference, the various radicals have the following meaning
the symbols R represent methyl radicals
the symbol A represents the naphylene-1,5 radical, the tetramer of α-methylstyrene, the radicals of formulas

the identical or different symbols G 'represent trimethylsilyl-phenyl, bis (trimethylsilyl) phenyl or tris (trimethylsilyl) phenyl radicals, these G' radicals possibly being partly replaced by identical or different radicals G and representing phenyl radicals; or else, and only, when the symbols R 'represent hydrogen atoms, radicals of formula

- the symbols are zero
the symbols n and n 'represent arbitrary numbers whose sum is between 30 and 400
the symbol m represents any number between 10 and 1200
By way of illustration, thermoplastic spheres may be mentioned, those whose patterns correspond to the formulas

<tb> hereinafter <SEP> r
<tb> f <SEP> CH2CH2 (CH3) 2Si <SEP> t <SEP> cle <SEP> Cu2 <SEP> l <SEP> II <SEP> 2 <SEP> l <SEP> 1Si (CH3) <SEP> not
<tb><SEP> CR <SEP> CH2 <SEP> CH2 <SEP> If (GH3 - ,: I :: "" ,, T
<tb> L <SEP> Cu2Ca2-Si <SEP> (Cu3) <SEP> 24osi <SEP> (Cu3) <SEP> 2 <SEP> +
<tb><SEP> 2
<tb><SEP> n5 <SEP> n <SEP> = <SEP> 58
<tb> CH2CH2 (CH3) 2Si <SEP> n6 <SEP> (CH3) <SEP> CH2 <SEP> X <SEP> A1 <SEP>, <SEP> CH2C (CH3) <SEP> - <SEP> ~~ ~~~
<tb> t <SEP> CC! <SEP> C6H4-Si (CH3) 3 <SEP> 6 <SEP> 1 <SEP> C6 <SEP> 4
<tb><SEP> H, -Si (CH,)? <SEP> ng
<tb><SEP> CH2CH2Si (CH3) 2 <SEP> - <SEP> OSi (CH3) 2 <SEP>;
<tb><SEP> n6 <SEP> n <SEP> 6 <SEP> 45
<tb><SEP> n <SEP> =
<tb><SEP> 6 <SEP>n'6<SEP> = <SEP> 45
<Tb>
It should be understood that copolymers which simultaneously comprise non-silylated polystyrene units and silylated polystyrene units form part of the subject of this certificate of addition.

As a preference, the copolymers according to the invention consist of silylated polystyrene units and polysiloxane units.

 The process for preparing the thermoplastic elastomers according to the invention is easily carried out in 3 phases according to an analogous mode making it possible to obtain the elastomers of formula F and described in the French patent application 78/26 245.

The first phase of the process consists in anionically polymerizing a monomer of formula CG 'R' = CH 2 in which G 'is a silylated phenyl radical or several monomers having the formula
CG'R '= CH2, at least one of the monomers being such that G' represents a silylated phenyl radical, the other monomers may then comprise non-silylated radicals G '. By way of examples of monomers, mention may be made of styrene or methylstyrenes substituted on the benzene ring by 1, 2 or 3 triorganosilyl radicals and in particular p-trimethylsilylstyrene, p-trimethylsilylmethylstyrene, bis (trimethylsilyl). ) 3,5-styrene, bis (3,5-trimethylsily) -3-methyl-styrene. These various monomers can be used alone or in mixture with one another or else in a mixture with other styrenic derivatives, these being unsulphonic such that styrene or a derivative thereof chosen from (1) α-methylstyrene, (2) styrenes substituted on the phenyl ring by 1, 2 or 3 methyl radicals (it is considered that the vinyl radical of the substituted styrenes is in position 1 on benzene) such as 2-methyl styrene, 3-methyl styrene, 4-methyl styrene, 2,4-dimethyl styrene, 2,5-dimethyl styrene, 3,4-dimethyl styrene, dimethyl -3,6 styrene, trimethyl2,4,5 styrene, the trimer 2,4,6-thyl-styrene (3) styrenes substituted on the phenyl ring by a dimethylamino or diethylamino radical such as 4-dimethylamino-styrene, 3-diethylamino-styrene. Preferably, among these unsulphonated monomers, styrene, α-methylstyrene, trimethyl, 4, 6 styrene (vinylmesitylene), 4-dimethylaminopyrene, etc. are chosen.

 The anionic polymerization takes place in anhydrous organic solvents, at a temperature of less than -300 ° C. but hardly falling below -850 ° C., using an initiator of formula A (M) 2.

The symbol A has the meaning already given relating to the formula F and the symbol M represents an alkali metal atom such as potassium, sodium, lithium, preferably potassium.

 The organic solvents used are chosen from linear branched or cyclic organic ethers such as dimethyl ether, diethyl ether, diisopropyl ether, dibutyl ether, tetrahydrofuran or from diols of glycols such as dimethoxy. -1.2 ethane.

 The amount of solvent used represents from 60 to 98% of the weight of the reaction medium; it depends on the solubility of the polymers in this medium and the temperature at which the polymerization will be carried out.

 The initiators of formula A (M) 2 are preferably chosen from oligomers with dicarboanionic sites with potassium or sodium counter-ions.

The preparation of this type of initiator is well known; it is described for example in the article by CL LEE, J. SMID and
Mr. SZWARC published in Trans. Farad. Soc. 59 - 1192 (1963) and in the article by GREBER G., E. REESE, A. BALCIUNAS published in Farbe Und-Lack 70 NO 4 - 249 (1964)
Thus they can be obtained by contacting potassium or sodium, in organic ethers-oxide medium, with the styrenic monomers, the alkali metal / monomer ratio varying from about 0.5 to 2.

 They can also be obtained under the same operating conditions by the use of naphthalene-potassium or naphthalene-sodium in place of potassium or sodium.

Among these oligomers with dicarboanionic sites may be mentioned, for illustrative purposes, the dipotassic or disodium tetramer of α-methylstyrene, the dimers of formulas

 The initiators may be further selected from organic dilithians such as dilithiostilbene, 1,5-dilithio-naphthalene, 1,5-dilithio-pentane.

 The preparation of these dilithians is known, it is described for example in the British patents 906 315 and 972 246.

 The initiators may be prepared in another reactor than that in which the anionic polymerization will take place and possibly well before this polymerization, or in this reactor at the same time as the polymerization.

 The styrene monomer / initiator molar ratio largely determines the molecular weight of the polymers to be prepared. This ratio can be in a wide range of values ranging for example from 20 to 500, resulting in number average molecular weights ranging from 2000 to 75,000.

 However, for the polymerization reaction to develop optimally (having a high conversion rate of monomers to polymers, for example greater than 90%) it is preferable that the monomer / initiator ratio ranges from 30 to 400. resulting in number average molecular weights ranging from 3,000 to 60,000.

 The polymerization time depends mainly on the structure of the monomers; it can therefore be a few minutes with styrene and several hours with vinylmesitylene which has a sterically hindered phenyl nucleus.

dans laquelle les symboles R', A, G', n, n' et M ont la signification précédemment indiquée relative à la formule F'.The living polymers obtained during this first phase correspond to the following formula

in which the symbols R ', A, G', n, n 'and M have the previously indicated meaning relating to the formula F'.

 During the second stage of the process, the living polymers obtained above are reacted with organochlorosilanes of formula (CH 2 CHCH) (R) 2 SiCl (in the same meaning as indicated above) in a proportion of at least 1 mole of organochlorosilane per gram of alkali metal. The living polymers are preferably brought into contact with the organochlorosilanes, without the protection of an inert gas atmosphere, at the end of their preparation and within the solutions in which they were prepared. This precaution is recommended since living polymers are generally not very stable at room temperature.

The second step of the method is then a functionalization step which makes it possible to replace the terminal groups.

by the following new terminal groups:

 The chlorosilanes used during the second stage of the process may be chosen, by way of illustration, from those of formulas (CH 2 = CH) (CH 3) 2 SiCl; (CH 2 = CH) (CH 3) C 2 H 5 SiCl (CH 2 = CH) (CH 3) C 6 H 5 SiCl; (CH2 = CH) (CH3) (n-C3H7) SiCl; (CH2 = CH) (CH3) (CF3CH2-CH2) SiCl.

 Preferably, vinyldimethylchlorosilane and vinylmethylphenylchlorosilane are used.

 It is recommended to introduce the excess chlorosilanes representing for example 2 to 8 times the molar amount necessary to neutralize the alkali metals M.

il est judicieux d'utiliser dans cette deuxième phase une température de réaction aussi basse que possible.To avoid side reactions, especially those from the attack of vinyl radicals chlorosilanes by groups

it is advisable to use in this second phase a reaction temperature as low as possible.

Thus temperatures between -500C and -1200C are remarkably suitable for achieving a virtually complete substitution.

en incorporant à chaque extrémité de la chaine des polymères vivants un motif de formule -cH2-C(C6H5)2-
Cette incorporation est aisément obtenue par mise en contact d'au moins 2 moles de diphényléthylène avec une mole des polymères vivants précédemment définis, /ce qui correspond à 1 mole de l'amorceur à , une température de l'ordre de -10 C à 700C dans le milieu réactionnel de formation des polymères vivants. Le diphényléthylène ne sthomopolymerise pas ; il en résulte la fixation d'un seul motif -CH2-C(H6H5)2 - en bout de chaine et l'obtention des nouveaux polymères

If it is desired to operate at higher temperatures, it is appropriate to reduce the reactivity of the group

by incorporating at each end of the chain of living polymers a unit of formula -cH2-C (C6H5) 2-
This incorporation is easily obtained by placing at least 2 moles of diphenylethylene in contact with one mole of the living polymers previously defined, corresponding to 1 mole of the initiator at a temperature of the order of -10 ° C. to 700C in the reaction medium for forming living polymers. Diphenylethylene does not homopolymerize; this results in the fixing of a single pattern -CH2-C (H6H5) 2 - at the end of the chain and the obtaining of the new polymers

<tb> alive <SEP> from <SEP> next <SEP> formula
<tb> MC (C6H5) 2-CH2- <SEP> CCR '<SEP> - <SEP> CH2 <SEP> A <SEP> A <SEP> CGIR <SEP> j <SEP> n
<tb><SEP> CH2-C (C6H5) 2-M
<Tb>
Then the organochlorosilanes are introduced into the reaction medium at temperatures of the order of -300C to 600C; in this temperature range there are no parasitic side reactions, only the substitution reaction takes place.

 Whether the polymers have, or not, at each end of their chain a -CH2-C (C6H5) 2- motif, the substitution reaction of the alkaline atom X with the SiRCH = CH2 group is very rapid. It is therefore not advisable to abandon the reaction mixture at the low temperatures precipitated after the end of the addition of the organochlorosilanes for a period exceeding 1 h. In general, the organochlorosilanes are rapidly introduced into the cooled solution of the living polymers and, after removal of the cold source, the reaction mixture is allowed to return to ambient temperature.

 It is also possible to introduce the cooled solution of living polymers into organochlorosilanes, but this process often requires the use of more complex equipment.

 Functionalized polymers are precipitated by diluting the reaction mixture with a compound in which they are poorly soluble or insoluble. In this purpose, alkanols having from 1 to 5 atoms, such as methanol, ethanol, isopropanol, isobutanol and n-pentanol, are preferably used.

 Practically the reaction mixture is poured into a large volume of alkanol representing from 4 to 15 times its own volume; this results in the precipitation of the polymers which are then filtered, washed once or several times with the alkanols and dried at a temperature of the order of 500C to 1800C under a pressure less than or equal to atmospheric pressure.

Polystyrene difunctional polymers obtained

<tb> tooth <SEP> to <SEP> the <SEP> formula <SEP> F2 <SEP>:
<tb><SEP> 1 <SEP> b
<tb> (C =CH) SiR2 CC (C6Hs) 2-CH2 <SEP> CR '<SEP> - <SEP> CH2 <SEP> j <SEP> Δ <SEP> H2 <SEP> b
<tb> L <SEP> CH2-C (C6H5) 2 <SEP> + <SEP> SiR2 (CH = <SEP> CH2)
<tb><SEP> a
<tb> in which the symbols R, R ', A, G', a, n and n 'have the meaning indicated above relative to the formula F.

 These symbols of the formula F2 also have the preferred meaning established for the symbols of the formula F '.

By way of illustration, difunctional polymers may be mentioned as those corresponding to the formulas below.

 The symbols ng, n5, n6, n6 and A1 having the meanings previously indicated.

 They are solid, whitish products with no elastomeric properties.

 In the third stage of the process for preparing the thermoplastic elastomers, the difunctional polymers obtained during the second stage of the process are reacted, under the usual conditions of the hydrosilylation reactions, with liquid α-dihydrogenopoly-diorganosiloxanes of the general formula mean HSiR2 (0SiR2) in which the symbols R and m have the meaning previously indicated.

 These α-β-dihydropenopolydiorganosiloxanes are available on the market silicones, further their preparation techniques are now well developed (French applications 2,225,480, 2,283,934 and 2,300,771).

 The molecular weight of these polysiloxanes is variable, it is determined by the nature of the substituents R and especially by the value of m which can range from 1 to 1500, preferably from 10 to 1200, it follows that these polysiloxanes have a variable viscosity which generally ranges from a few cPo at 250C to 500,000 cPo at 250C.

As specific examples of these polysiloxanes may be mentioned those of formulas HSi (CH3) 20Si (CH3) 2H; HSi (CH3) 2

<tb>#OSi (CH3) 2 # m1H
<tb> m, taking the values 4, 6, 85, 125, 178, 230.

<Tb>

HSi (CH3) 2 <SEP>#OSiCR (C2H5) # 5 <SEP>#OSi (CH3) 2 # 150 <SEP> H
<Tb>

<tb> HSi (CH3) 2 <SEP> OSiCH3 (CH2CH2CF3) <SEP> 11 <SEP> OSi (CR3) 2 <SEP> 90 <SEP> H
<tb> HSi (CH3) 2 <SEP>; OSiCH3 (C6H5) i <SEP> 16 <SEP> OSi (CH3) 2 <SEP> 310 <SEP> H
<Tb>
The amounts in the presence of the polymers of formula F 2 and of the dihydrogenopolydiororganosiloxines are such that the molar ratio number of vinyl groups provided by the polymers / number of groups
SiH provided by the polysiloxanes ranges from 0.7 to 1.3, preferably from 0.9 to 1.1.

 The polyblock copolymers resulting from this hydrosilylation reaction are terminated at each end of their chain by SiH and / or Si-CH = GH2 groups. However, it is possible to have other blocking groups by introduction during the hydrosilylation reaction of organosilicon compounds bearing an SiH group such as trimethylmonohydrogensilane or organic or organosilicic compounds having a vinyl radical such as styrene or trimethylvinylsilane.

 This hydrosilylation reaction, which leads to a polyaddition of the two reagents, is catalyzed by metals of group VIII of the periodic table of elements or by their mineral or organic derivatives. Among these metals may be mentioned platinum, palladium, ruthenium, rhodium, iridium.

 It is recommended to use the platinum which can be introduced in the form of elemental platinum deposited on various supports (alumina, silica, carbon black) or better in the form of its chlorides such as those of formula: Cl2Pt, Cl Pt H2PtCl6.6H20. In addition, these chlorides can be modified by contacting with appropriate organic compounds; Thus, on the one hand, the reaction products of chloroplatinic or hexachloroplatinic acid with alcohols, ethers, aldehydes (US Pat. No. 3,220,972) and on the other hand the complexes formed between platinic chlorides and olefins (U.S. Patent 3,159,601) or phosphines or alkyl sulfides.

 The amounts used of these catalysts are low, of the order of 0.5 to 30 parts by weight, based on the metal, for 1 million parts by weight of reactants (polymers of formula F 2 + a-w dihydrogenopolydiorganosiloxanes used).

 The polyaddition reaction is preferably carried out in solutions containing suitable diluents. This avoids unwanted precipitation of polymers and runaway reaction mixtures.

 The diluents used may be chosen from: aliphatic and cycloaliphatic hydrocarbons, halogenated or not, such as pentane, hexane, heptane, chloroform, dichlorethane, tetrachloroethane, trichloroethene, perchlorethylene, chloride methyl, cyclohexane, methylcyclohexane, decalin.

aromatic hydrocarbons, halogenated or not, such as toluene, xylene, tetralin, chlorobenzene or orthodichlorobenzene.

aliphatic esters of monocarboxylic acids such as ethyl acetate, butyl acetate and amyl acetate.

 The proportion of diluents in the solutions is variable, depending for example on the solubility of the starting materials and the copolymers formed, it is preferable, however, to use solutions containing from 25 to 75% by weight of diluents and better still from 35% by weight. 65 2.

 The reaction temperature must be sufficient to cause the polyaddition reaction and maintain an acceptable rate of formation of the copolymers. Generally this temperature is in the range 809C to 2209C. The reaction time is a function of the nature of the reagents and the catalyst and the temperature at which one operates.

It can range from 30 minutes to 30 hours.

After completion of the polyaddition reaction, which can be analytically determined by the disappearance of the SiH groups and
If -CH = C, the copolymers of formula F 'are precipitated by dilution of their reaction medium with compounds in which they are little or not soluble.

 The technique used is similar to that described previously in the 2nd phase for the separation of polymers of formula F2.

The copolymers, which correspond to the precipitated formula F ', are then filtered, washed and dried. These are solid products with softening points of the order of 150-2500C. The molecular weights of these copolymers depend on the aforementioned molar ratio, number of SiCE groups = CH 2, provided by the polymers / number of groups
SiH provided by the dihydrogenopolydiorganosiloxanes, as well as the course of the polyaddition reaction; they can range from 20,000 to 2 million.

 These copolymers are thermoplastic elastomers whose elastomeric properties are mainly a function of the nature and the weight ratio of the silylated polystyrene blocks and the diorganopolysiloxane blocks constituting each unit.

 It is however recommended to manufacture copolymers having from 30 to 85% by weight of diorganopolysiloxane blocks. When this percentage is low, between 30 and 40%, the copolymers have high mechanical properties, of the order of those of purely organic polymers or copolymers. By cons when this percentage exceeds 45 - 50%, the copolymers have lower mechanical properties, which are nevertheless greater than those of the usual organopolysiloxane elastomers.

 These copolymers are characterized by a good temperature resistance, higher than that exhibited by purely styrenic polymers. Indeed their elastic modulus varies slightly over a temperature range from room temperature to temperatures exceeding 1000C.

 These copolymers can be converted using rubber techniques or those of plastics transformers into joints, profiles, insulating or protective coatings, solid fibers. Such objects can be used in many fields of industry such as automotive, electrical engineering.

 In addition, these copolymers, because they comprise diorganopolysiloxane blocks, have good gas permeability. They can therefore be used for the preparation of membranes with selective gas permeability (for example as artificial lungs) or for separating at least one of the constituents of gas mixtures. Being physiologically inert, they can also be used for the manufacture of prostheses in contact with human tissues (for example as catheters, various implants, heart valves).

 Up to 100% of their weight, pulverulent fillers chosen from among the various kinds of silica, calcined clays, carbon blacks, metal oxides, alkali metal and alkaline carbonates can be incorporated into these copolymers. earthy and magnesium, aluminum or zirconium silicates.

 The polydiorganosiloxane and silyl polystyrene thermoplastic elastomers have, with respect to polydiorgano siloxane, unsilylated polystyrene elastomers, higher mechanical properties, with an equal content of polysiloxane units. Substantially increased compatibility is also observed in the polyaddition reaction between the α, bis-bis-vinylsilylated polystyrenes and the α, hydrogenopolysiloxanes.

EXAMPLE 1 14.3 g of p (trimethylsilyl) styrene (obtained by magnesium synthesis from chlorotrimethylsilane and p-hromostyrene) are added to a solution containing 150 ml of tetrahydrofuran and 7 cm of a dipotassium tetra- mer solution. of amethylstyrene, and normality 0.206. Once the polymerization is complete, the temperature of the reaction medium is lowered to -85 ° C. and 1 cm 3 of chlorodimethylvinylsilane is added.

 Precipitation in methanol, after washing, filtration and drying, collected 14.2 g of polytrimethyl (vinyl-4 ') phenylsilane.

This product has a number-average molecular weight, determined by permeate gel chromatography M GPC = 10 500 g / mol
n, GPC and a weight average molecular weight, determined by light scattering Mw, DDL = 10,900 g / mol.

 Its glass transition temperature determined by differential calorimetry is 13 ° C.

avec n5+n'5 = 58 ; A1 représentant le reste du tétramère de l'a méthylsty rène. The polymer thus meets the average general formula:

with n5 + n5 = 58; A1 represents the rest of the tetramer of methylstyrene.

The polystyrenic-polysiloxane copolymer is then prepared as follows 3
5 g of the "polystyrene" and 8.55 g of polydimethylsilane α,--dihydrogenosilane having a mass average of 17,100 g / mol are added to 16 cm of toluene, the temperature of the reaction medium is raised to 95 ° C. and 0.025 ml of solution containing 10 g / l of U2PCl6.6H2O in isopropanol is introduced.

 The medium is homogeneous after about 10 minutes. Total reaction time t 18 hours.

 The multiblock copolymer is recovered by precipitation in methanol. After washing, filtration and drying, 100% weight-average molecular weight copolymer determined by light scattering was collected.

Mw, DDL = 107,000 g / mole
The units constituting this copolymer correspond to the form:

EXAMPLE 2
According to the procedure described in Example 1, 25 g of p (trimethylsilyl), α-methylstyrene (obtained by magnesium synthesis from chlorotrimethylsilane and p-bromo, α-methylstyrene) are introduced into a solution containing 250 ml of tetrahydrofuran and 13.2 cm of a dipotassium tetramer solution of methylstyrene and Q210 N.

 When the polymerization is complete, 1.5 cm 3 of chlorodimethylvinylsilane are added to the solution, previously cooled to -5 ° C.

 The polymer is precipitated in methanol, washed and dried.

25 g of poly-trimethyl (isopropenyl-4 ') phenylsilane are thus obtained.
Mn, GPC = 9,200 g / mole.

Glass transition temperature: 1590C.

avec n6 + n' 6 =
A1 représente toujours le reste du tétramère de l'a méthylstyrène.The polymer thus meets the average general formula

with n6 + n '6 =
A1 always represents the rest of the tetramer of methylstyrene.

The polystyrenic-polysiloxane copolymer is then prepared according to the conditions of the previous test 3
To 33 cc of toluene was added 10 g of the above "polystyrene" and 19 g of the same polydimethylsilane as used in the synthesis of the example. 0.030 ml of the catalyst solution is added to the medium, brought to 950C. The solution is homogeneous after about 15 minutes.

Total reaction time: 4 hours
100% of multiblock copolymer is recovered.

Mw, DDL = 180,000 g / mole
The copolymer is then constituted by the units of formula:

From this copolymer, rubbery plates are prepared by hot molding.
These plates have a tensile strength of 123 kg / cm 2.

The elongation at break is 786%.

Claims (2)

 the identical or different R symbols represent methyl, ethyl, n-propyl, phenyl or 3,3,3-trifluoropropyl radicals.  in which

 average general formula F '  what they are formed of a succession of patterns responding to the  claim 1 of the main application 78/26,245, characterized in that  1 - polydiorganopolysiloxane polystyrene elastomers according to the  the symbol A represents a divalent hydrocarbon radical, without ethylenic unsaturation having from 6 to 45 carbon atoms, and chosen from naphthylene, biphenylenes, alkylene or polyalkylene radicals optionally substituted with aromatic rings.  the identical or different symbols R 'represent hydrogen atoms or methyl radicals  - represents an integer equal to 0.1 or 2.  - Rt 'represents a hydrogen atom, a methyl radical, or an SiR3 group  and in which

 the identical or different symbols G 'represent silylated aromatic radicals having the formula  - R has the meaning previously given.  500.  any number that is between 20 and  the symbols n and n 'which are identical or different  the identical symbols a represent zero or 1  The symbols G 'may optionally be partly replaced by identical or different radicals G and representing radicals of formula Cg (H) S ~ b (CH3) b in which the symbol b represents 0, 1, 2 or 3, or radicals of formula -C6H4-N (CH3) 2  between 1 and 1500;  - the symbol m represents any number included  Thermoplastic elastomers according to claim 1, characterized  in that the various symbols, which define the general formula  F ', have the following meaning  the symbols R represent methyl radicals  the symbol A represents the naphylene-1,5 radical, the tetramer of amethylstyrene, the radicals of formulas

 the identical or different symbols G 'represent trimethylsilyl-phenyl, bis (trimethylsilyl) phenyl or tris (trimethylsilyl) phenyl radicals, these G' radicals possibly being partly replaced by identical or different radicals G and representing phenyl radicals; or else, and only, when the symbols R 'represent hydrogen atoms, radicals of formula  at least one monomer comprising, as a group G ', a silylated phenyl radical, using initiators of formula A (M) 2 in which the identical M symbols represent potassium, sodium, or lithium, in organic ether oxides, at a temperature between -850C and -300C.

 the anionic polymerization of one or more monomers of formula  (a) we realize in a first phase  phases such as  claim 1, characterized in that said method comprises 3  the symbol m represents any number between 10 and 1200 3 - Process for the preparation of thermoplastic elastomers according to the  the symbols n and n 'represent arbitrary numbers whose sum is between 30 and 400  - the symbols are zero

 The molar monomer / initiators ratio being between 20 and 500, which leads to living polymers of formula

 and then optionally bringing the preceding reaction mixture into contact with diphenylethylene of formula C (C6H5) 2 = CH2, in a proportion of at least 2 moles of diphenylethylene per 1 mole of living polymers, which leads to novel living polymers of formula

 polymers / previously obtained by contacting the reaction medium with vinylorganochlorosilanes of formula (CH 2 CRCR) 2 -S; LÇC in a proportion of at least 1 mole of these silanes per 1 gram atom of alkali metals M leading to polysty difunctional polymers  (b) in a second phase the neutralization is carried out  (c) in a third stage, the polyaddition is carried out between the polymers of formula F 2 and the dihydrogenodiorganopolysiloxanes of formula HSiR 2 (ORSi 2) H, in a ratio of number of vinyl groups of the polymers F 2 / number of SiH groups of the polysiloxanes between 0.7 at 1.3, in the presence of metal catalysts, or their mineral or organic derivatives, selected from the group consisting of platinum, palladium, ruthenium, rhodium, irridium. <Tb> <tb> LSi (R) 2 <SEP> {C2-, <SEP> CH2) <tb> <SEP> 6522Aa2n <SEP> E2G '<SEP> ~ <SEP> n <SEP> 2-C (C6H5) 2 <tb> (CH2 = CH) sL (RWC (CH) HR'-CH <SEP> A <SEP> '-CH2 <SEP> f <SEP> ATCH-CRmCH <tb> repies <SEP> of <SEP> formula <SEP> F2 <SEP>::  The symbols R, R ', G', A, a, n, n ', m, have the meaning given in claim 1.