IE42610B1 - Thermoplastic polysiloxane elastomers - Google Patents

Abstract

1517557 Polysiloxane elastomers having organic linkages RHONE POULENC INDUSTRIES 30 Sept 1975 [1 Oct 1974 11 Feb 1975] 40055/75 Heading C3T A thermoplastic polysiloxane elastomer contains units of the formula wherein each R<0> is a C2-10 alkylene or cycloalkylene radical optionally bearing 1-4 Cl or F atoms; each # is a direct bond or -SiR2-, -SiR2O-, -SiR2-(CH2)1-3- or -SiR2- C6H4- (R being Me or Ph); each R<1> is an alkyl, haloalkyl, cyanoalkyl, aryl or haloaryl radical, each R<2> is a C1-4 alkylene or alkylidene radical; each X is -O-, -S- or -NR<4>- or -CO-O-, -CO-S- -CS-O- or -OS-S- attached to R<2> via O or S (R<4> being H or C1-6 alkyl); each # has 1-30 C atoms and is (i) an optionally chlorinated alkylene, alkylidene, cycloalkylene or arylene radical or a a mono- or poly-cyclic divalent saturated, unsaturated or aromatic heterocyclic radial, or two or more such radicals linked directly or via -O-, -S-, -NR<4>-, -COO-, -CONR<4>-, O -SO2-, -N=N-, -N=N-, -CO- or -PO(R<5>)- (R<5> being C1-4 alkyl, cyclohexyl or phenyl) or (ii) a benzenetriyl, naphthalenetriyl, pyridinetriyl or =C6H3-E-C6H4- radical (E being C1-4 alkylene or alkylidene, -O-, -S-, -COO-, -SO2-, -CO- or -CONH-) in which one valency is attached to X and the other two to T below when T is each # is -O-CO-0-, -NR<4>-CO-NR<4>-, -NR<4>-CO-O, -O-CO-CO-O-, -SCO-CO-S-, -NR<4>-CO-CO-NR<4>, -T-R<11>-T-, wherein R<11>, R<111> and R<1111> are di-, tri- and tetra-valent organic radicals and each T is -CO-O-, -CO-S-, -CO-NR<4>-, -NH-CO-NR<4>-, -NH-CO-O- or -NH-CO-S- attached at either end to a divalent group #, or is attached via the -CO- groups to trivalent #; and n is 1-2000. They are prepared by reaction of the silanes in which each R is a C2-10 ethylenically unsaturated organic radical, with the siloxanes H-SiR<1>2-(OSiR<1>2)n-H. In examples silanes having two groups CH2=CH-SiMe2-CH2O- linked by the sequences (Examples 1 and 2 and 8-11), (Examples 3 and 4), (Example 5), (Example 6) and (Example 7), are added in place of a Pt catalyst to siloxanes HMe2Si(OSiMe2)nH, where n is 14 to 37, in toluene, cyclohexane, dioxan or butyl acetate. The products, in the same solvents or chloroform, are cast into films, or moulded into sheets. The unsaturated silanes are the subject of copending Specification 1,517,558.

Description

THIS INVENTION relates to thermoplastic polysiloxane elastomers.

Silicone rubbers have acquired considerable industrial importance because of their special chemical, physical and mechanical properties and especially because of their behaviour towards cold and heat. These elastomers are obtained, by a long and delicate process, from elastomeric siloxane gums which are themselves in the form of more or less viscous products devoid of valuable mechanical properties. These gums are prepared by polymerisation of cyclic siloxane oligomers or by polycondensation or copolycondensation of siloxane oligomers with terminal functional groups (for example alkoxy, hydroxyl and/or chlorine). The production of the silicone rubbers from polysiloxane gums requires firstly the preparation of masterhatches by incorporating into the gum various ingredients such as fillers (and especially silica in a great variety of forms),pigments and -2vulcanising agents, followed by the vulcanisation of these masterbatches, for example by heating in the presence of organic peroxides or, in the case of polysiloxane gums with terminal functional groups, by a cold treatment using polyfunctional crosslinking agents (e.g. silicates, trialkoxysilanes and triacetoxysilanes). Regardless of the process employed, the vulcanisation, which makes it possible to convert a gum devoid of valuable mechanical properties to a rubber, must be preceded by the moulding of the desired objects because the vulcanised product is devoid of any thermoplasticity. On the other hand, the incorporation of fillers into the polysiloxane gums has proved indispensable; in effect, the silicone rubbers obtained by vulcanisation of unfilled gums have such low mechanical properties that they have not found any practical use. In certain cases the introduction of the fillers into the polysiloxane gums can have the effect of forming a mixture which is difficult to handle during the moulding process because of an interaction between the filler and the gum; it is then necessary to overcome this disadvantage by incorporating ingredients intended to minimise this interaction or to restore sufficient plasticity to the masterbatch. All these operations complicate the process of obtaining silicone rubbers and prove costly from an economic point of view.

Attempts have been made to avoid the disadvantages referred to above whilst preserving the remarkable properties of silicone rubbers, by proceeding to develop thermoplastic elastomeric polymers. The method generally used to -3arrive at this objective consists of combining polysiloxane units and units of organic polycondensates in one polymeric chain. Thus it has been proposed in U.S. Patent No. 3,189,662, to obtain block copolycondensates containing polydiorganosiloxane units and units of polycarbonates of aromatic diols by reaction of an a-ω-dihalogenopolysiloxane with a diphenol in the presence of a halogen acceptor, to form an intermediate condensate which is then treated with phosgene. Although the polycondensate thus obtained is elastic, it has the disadvantage of containing, in its chain, Si-O-C bonds of which it is known that they are less stable to hydrolysis than the silicon-carbon bonds. It has also been proposed to prepare polymers containing polydiorganosiloxane unites linked to one another by purely organic units via intermediate siliconcarbon bonds. Thus it has been proposed, in U.S. Patent No. 3,176,034, to prepare copolymers containing a plurality of polydiorganosiloxane blocks linked to one another by organic units of the formula: in which X is a halogen or hydrogen atom or a methyl radical, Y is an alkylene radical and a is 0 or 1, by reaction of an «,ω-dihydrogenopolydiorganosiloxane with allyl diethers of bisphenols in the presence of the usual hydrosilylation catalysts. The polymers thus obtained are thermo-442610 plastic fluids which must be converted by crosslinking when they are used. In effect it has been found that no satisfactory solution has been provided to the problem of obtaining elastomeric thermoplastic polymers which simultaneously have the remarkable properties of silicone rubbers and excellent stability to hydrolysis. The present invention provides a solution of this problem.

More precisely, the present invention provides polysiloxane thermoplastic elastomers, which possess a plurality of recurring units of the general formula: in which the various symbols have the following meaning: Rq and R’q which may be identical or different, represent a linear or branched alkylene group or a cycloalkylene group optionally substituted by 1 to 4 atoms of chlorine and/or fluorine, said group containing from 2 to 10 carbon atoms. λ and λ1, which may be identical or different, denote a valency bond or one of the followincj organosilicon groups: (II) (III) (IV) (V) 43®&© wherein the radicals R, carried by the silicon are identical or different and represent a methyl radical or a phenyl radical, and nj_ is 1, 2 or 3. Ι<1» R'j, and to Q&, which may he identical or different, are linear or branched alkyl radicals optionally substituted by one or more halogen atoms or by cyano groupa or aryl radicals or alkylaryl radicals, optionally substituted by one or more halogen atoms.

R2 and R12' which may be identical or different, represent a linear or branched alkylene or alkylidene radical containing from 1 to 4 carbon atoms.

X and X' which may be identical or different represent a functional group of the formula: -0-, -S-, -C-0-, -C-S-, -C-0-, -C-S- or -Mli li II II I 0 S S R^ said group being linked by a hetero atoms to the radicals R2, R2‘, and wherein R^ is a hydrogen atom or an alkyl radical containing from 1 to 6 carbon atoms. Ϊ and f which may bs identical or different are organic radicals containing from 1 to 30 carbon atoms, chosen from the group consisting of (1) a divalent radical which is a linear or branched alkylene radical, an alkylidene radical or a cycloalkylene radical, optionally substituted by one or more chlorine atoms, a monocyclic or polycyclic arylene radicaloptionally substituted by one or more methyl radicals and/or more than one chlorine atom, a saturated or unsaturated or aromatic monocyclic or polycyclic heterocyclic radical containg at least one Ο, N or s atom optionally substituted by one or more methyl radicals, or a chain of alkylene and/or alkylidene and/or eycloalkylene and/or arylene and/or divalent heterocyclic radicals linked to one another by a valency bond and/ □r by at least one of the groups;-0-, -S~, -NIJ», -C00-, tCQEJR^-, 0 · » T -SO--, - -N=N-, -N=N“, -C- and -Σ’- (XI) 2 4 li I ,0 . r5 wherein Rg represents an alkyl radical having from 1 to 4 carbon atoms, a cyclohexyl radical or a phenyl radical: or (2) a trivalent radical which is a benzenetriyl radical, a naphthalenetriyl radical, a pyridinetriyl radical, or a radical of the formula (XII) in which E represents a valency bond or an alkylene or alkylidene group having from 1 to 4 carbon atoms, an oxygen atom, a sulphur atom or one of the groups: -COO-, -SO--, -C- and -C-NH-, 2 II II 0 0 in which one of the free valencies is attached to x or X*, respectively, and the remaining two valencies are attached to the carbonyl group in formula (XX) below; yis an organic radical chosen from the groups of the formula: -0-C-0-, -NRi-C-NR,- or -NR/.-C-O-, H 11 4 4 « 0 0 ^COC0_ co -T-RM-T'- (VII), or -Ν ^R ^CO^ \ co‘N - (IX), (VIII) in which R represents a divalent organic radical, or, additionally, a valency bond when -T-R-T’- represents -O-C-C-O, -S-C-C-S- or -NR.-C-C-NR, II II tt tl 4 II II 4 0 0 0 0 0 R· represents a trivalent organic radical.

R represents a tetravalent organic radical.

T and T‘ represent identical or different functional groups chosen from the groups of the formula (X): V 42S10 CO-, -C-S-, -C-N-, -NH-CO-M-, -NH-C-O-, -MH-C-S· It either end of which may ba attached to a divalent group E or Ε’, or co- (XX) in which the carbonyl groups are attached to a trivalent group S or a ; and n is a number from 0 to 2,000.

More precisely, the various symbols which figure in the formulae (I) to (X) can, for example, assume the following meanings: I. Radicals R and R' o o These radicals represent h linear or branched alkylene group optionally substituted by 1 to 4 atoms of chlorine and/or of fluorine, or a cycloalkylene group optionally substituted by one to four atoms of chlorine and/or fluorine.

More specifically, RQ and R' symbolise ethylene, 1,3-propylene, 1,2-propylene, 1,4-butylene, 1,3-butylene 7a « 4261« 2,3-butylene, 1,5-pentylene, 1,4-pcntylene, hexamethylene, octamethylene, decamethylcnc, monochloroethylene, dichloroethylene, 1,2-difluoroeth/lene, 1,4-cyclohexylene and 1,3-cyclohexylene groups.

Preferably, Κθ and R’ represent linear alkylene groups containing from 2 to 6 carbon atoms.

II. Radicals and R'^ and to Qg They represent; in particular: Linear or branched alkyl groups having from 1 to 10 carbon atoms, optionally substituted by one to four atoms of chlorine and/or of fluorine or by a cyano group.

Phenyl groups optionally substituted by 1 to 4 atoms of chlorine and/or of fluorine.

Alkylaryl groups containing from 1 to 4 atoms of carbon in the alkyl radical, optionally substituted by 1 to 4 atoms of chlorine and/or of fluorine, such as the tolyl, xylyl and ethylphenyl radicals.

More specifically still, the following may be mentioned by way of examples of the radicals symbolised by R^, R*^ and to Qg: the methyl, ethyl, propyl, isopropyl, butyl, isobutyi, a:-pentyl, t-butyl, chloromethyl, dichloromethyl, a-chloroethyl, a,βdichloroethyl, fluoromethyl, difluoromethyl, α,β25 diflurorethyl, 3,3,3-trifluoropropyl, 4,4,4-trifluorobutyl, 3,3,4,4,5,5,6-heptafluoropentyl, β-cyanoethyl, γ-cyanopropyl, phenyl, p-chlorophenyl, m-chlorophenyl, 3,5-dichlorophenyl, trichlorophenyl, tetrachlorophenyl, ο-, p- or m-tolyl, α,α,α-trifluorotolyl and xylyl groups such —---8 as 2,3-dimethylphenyl and 3,4-dimethylphenyl, Preferably, the radicals R^, R1^ and to represent alkyl radicals having at most 6 carbon atoms, and phenyl, tolyl and xylyl radicals optionally substituted by 1 to 4 atoms of chlorine and/or of fluorine.

III. Radicals R^ and R'2 By way of specific examples, the following radicals may be mentioned; methylene, ethylene, 1,3propylene, 1,2-propylene, ethylidene, isopropylidene and tetramethylene.

IV. Radicals X and X1 j These represent oxygen, sulphur and the functional groups: -NR.-, -C00-, -C-S-, -C-0-, and -G-S4 is s s V. Radicals Γ and Γ* They represent radicals chosen from the group consisting of: 1. Divalent radicals which are: a straight or branched alkylene, alkylidene or cycloalkylene radical optionally substituted by one or more chlorine atoms or a monocyclic or polycyclic arylene radical optionally substituted by one or more methyl radicals and/or οηέ or more chlorine atoms.

A saturated or unsaturated or aromatic, monocyclic or polycyclic heterocyclic radical which contains at least one of the hetero-atoms 0, N and S and can optionally be substituted by methyl radicals: - 9 4 3«! ο the term polycyclic heterocyclic radical denotes a radical containing at least two heterocyclic structures or at least one heterocyclic structure associated with at least one aromatic or non-aromatic hydrocarbon ring, the combination forming an ortho-condensed, or ortho- and pericondensed, system. This meaning is intended throughout this specification.

A chain of several alkylene and/or cycloalkylene and/or arylene and/or divalent heterocyclic radicals, linked to one another by a valency bond and/or by at least one of the following divalent groups: -0-, -S-, -N-, -C00-, -CON-, -S02-, -N=N-, -N=^-, r4 r4 θ -CO- and -ί- (XI) R5 (wherein Rg represents an alkyl radical having from 1 to 15 4 carbon atoms, such as methyl, ethyl, n-propyl and nbutyl, a cyclohexyl radical or a phenyl radical), and/or by an alkylene or alkylidene group having from 1 to 4 carbon atoms, such as methylene, ethylene and isopropylidene Amongst the divalent radicals which have just 2(1 been mentioned they represent more particularly still: a) an alkylene or alkylidene radical having from 1 to 12 carbon atoms or a cycloalkylene radical having from 5 to 8 carbon atoms: by way of illustration there may be mentioned the methylene, ethylene, propylene, butylene, hexamethylene - 10 and cyclohexylene radicals. b) an arylene radical such as m-phenylene, p-phenylene, toluylene, such as 5-methyl—1,3-phenylene and 2-methyl-l,4phenylene, a xylylene radical such as 1,2-dimethyl-3,6phenylene, naphthylene and anthracenylene. c) a saturated or unsaturated or aromatic heterocyclic radical which contains one or more hetero-atoms Ο, N and S and 4 to 6 atoms in the ring, and is optionally substituted by one or two methyl groups; By way of illustration there may be mentioned the following radicals; a) a divalent radical consisting of a chain of 2 to 4 groups chosen from amongst those defined under a) and/or b) and/or c), linked to one another by a valency bond and/or by at least one of the groups -0-, -S-, -NH-, -C00-, -CONH, -SOj-, -Ν=Ν-, -N=N-, -CO- and 0 *5 and/or by an alkylene and/or alkylidene group having from 1 to 4 carbon atoms, such as those already mentioned.

As examples of such groups, there may be mentioned the following radicals: - 11 4 2 01° Preferably, Γ and Τ' represent an alkylene or alkylidene radical having from 1 to 6 carbon atoms, a cyclohexylene radical, a m- or p-phenylene, tolylene or xylylene radical, a radical formed by two phenylene groups linked to one another by a valency bond or by an alkylene or alkyliio dene group having from 1 to 4 carbon atoms (such as methylene, ethylene, propylene or isopropylidene), an oxygen atom or a -Nil-, -SO.-, -C-NH- or -CO- group. & If 2. The trivalent radicals Γ and Γ* in particular represent: a benzenetriyl radical such as 1,2,4-benzenetriyl, a naphthalenetriyl radical such as 2,3,6naphthalenetriyl, or a radical of the formula ,— E (xn) in which E represents a valency bond or an alkylene or alkylidene group having from 1 to 4 carbon atoms, such as those already mentioned, or a -0-, -S-, -C00-, -S02-( 4361 Ο -C- or -CONH- group» II Amongst the trivalent groups, land P' mors especially represent the groups: VI. Radical R It more particularly denotes: 1. A linear or branched alkylene radical, or alkylidene radical, a cycloalkylene radical, a monocyclic or polycyclic arylene radical which is optionally substituted by one or more alkyl radicals having from 1 to 4 carbon atoms, such as those already mentioned, and/or by one or two functional groups from amongst cyano, amide, nitro, ester g (especially me thy lcarbony lossy and methoxycarbonyl), alkoxy, hydroxyl, amine and hydroxycarbonyl and/or by one or more atoms of halogens, and especially of bromine, chlorine and fluorine. 2. A saturated or unsaturated aromatic monocyclic or polycyclic heterocyclic radical containing at least one of the hetero-atoms Ο, N and S, optionally substituted by methyl radicals. 3. A chain of several radicals as defined under 1) and/or - 13 -COO- : -CONR,- ; -SO.- ; -N=N- ; -N=N4 2 χί -P(R3^2 -Si (R3^2 - Si -0- Si - (CH ) n.

(R3^2 (R3^2 - Si -0- Si - (CH2) (R352 ^3½ Si - (CH2) - Si - (CII2) - and nl nl (R3}2 - Si - (CH.) - Si - (CII.) -02), linked to one another by a valency bond and/or an oxygen atom and/or a sulphur atom and/or by at least one of the groups: -N- : I R4 -CO- ; -(CII ) zn - (CH.) z I - ° - (C nl nl nl wherein R3 , R^, Rg and n^ have the meanings already given above.

Amongst the radicals which have just been mentioned, R more particularly represents: a) a linear or branched alkylene radical or alkylidene radical having at most 12 carbon atoms, or a cycloalkylene radical having from 5 to 8 carbon atoms in the ring.

By way of illustration there may be mentioned the following radicals: methylene, ethylene, ethylidene, 1,3-propylene, isopropylidene, butylene , cyclohexylene , hexamethylene and dodecamethylene. b) a phenylene, tolylene, xylylene, naphthylene or anthracenylene radical optionally substituted by one or more atoms of chlorine, by cyano, amide or ester (especially methylcarbonyloxy and methoxycarbonyl) groups or alkoxy groups having from 1 to 4 carbon atoms (for example methoxy). - 14 e) a saturated or unsaturated or aromatic heterocyclic radical which contains one or two hetero-atoms, which atoms are, independently, nitrogen, oxygen or of sulphur and contains from 4 to 6 atoms in the ring, and is optionally substituted by one or two methyl groups. The following radicals may be mentioned by way of illustration: d) a divalent radical consisting of a chain of 2 to 4 groups chosen from amongst those defined in paragraphs a) and/or b) and/or c) and linked to one another by a valency bond and/or an atom of sulphur and/or of oxygen and/or by at least one group of the formula: L5 -Ν- , -NHCO-, -C00-, -SO--, -Ν=Ν-, -Ν=ΪΓ-, -CO- and Ψ -PI R5 and/or by an alkylene or alkylidene group having from 1 to 4 carbon atoms, such as those already mentioned.

By v/ay of illustration there may he mentioned the i0 divalent groups already indicated for T and T’,to v/hich may bs added the groups of the formulae: Preferably, R represents an alkylene radical having from 1 to 8 carbon atoms, a cyclohexylene radical, a m- or p- phenylene radical, or a divalent radical containing 2 to 4 phenylene groups linked to one another by a valency bond and/or an oxygen atom and/or the groups ΐ -NHC0-, -CO-, -S02-, -NH-, -P- and -COOίο -P- and -COO- . and/or by a methylene and/or isopropylene group, or a radical containing two alkylene groups having from 1 to 4 carbon atoms linked to a benzene ring by a valency bond and/or an oxygen atom and/or the groups: -NH-CO-, -CO-, -S02-, -NH-, VII Radical R 1 and R1' They symbolise the following multivalent radicals: 1. A linear or branched saturated aliphatic hydrocarbon radical having from 2 to 20 carbon atoms. 2. A saturated cycloaliphatic hydrocarbon radical containing 5 or 6 carbon atoms. 3. A saturated or unsaturated or aromatic heterocyclic radical containing at least one of the atoms Ο, N and S and 4201 from 4 to 5 atoms in the ring» 4. A monocyclic or polycyclic aromatic radical in which the rings are fused or linked to one another by a valency bond and/or an alkylene or alkylidene radical having from 1 to 4 carbon atoms and/or an atom of oxygen and/or of sulphur and/or by at least one radical of the formulae: (Kill) (in which Δ represents an alkylene radical having at most 10 12 carbon atoms such as the methylene, ethylene, propylene and hexamethylene radicals, or a cycloalkylene radical having 5 or 6 carbon atoms (cyclohexylene) and R^ and have the meanings already indicated), the aromatic rings being optionally substituted by chlorine atoms and/or methyl groups.

More particularly, R1 and R, which are respectively trivalent and tetravalent, represent: «) a saturated aliphatic hydrocarbon radical containing from 2 to 10 carbon atoms, such as the radicals: >CH - CH< and -CH„ CH- β) a 1,2,4-cyclohexanetriyl radical or a 1,2,4,5-Cyclohexane' tetrayl radical γ) a heterocyclic radical of the formulae: - 17 * 2 610 and 6) a monocyclic or polycyclic aromatic radical such as the 1,2,4-benzenetriyl and 1,2,4,5-benzenetetrayl radicals and the radicals of the formulae: Preferably, R1 and R represent trivalent or tetravalent radicals containing 1 or 2 phenyl nuclei linked to one another by a valency bond or by an oxygen atom, a methylene radical, an isopropylidene radical, or a —SO.—, Q or 0 group.

J ? -C- -PI *5 VI11. Radicals T and T' They preferably represent one of the following groups CO -COO-, -CONH-, -NH-COO-, -NH-CO-NH- and -N CO X. n is preferably from 3 to 500.

Amongst the compounds of the formula (I), those particularly preferred are the compounds in which the - 18 42610 various radicals of the said formula have the following meanings: Rq = R'o is a linear alkylene radical having from 2 to 6 carbon atoms. λ = λ' is a valency bond.

R^ = R'^ is an alkyl radical having from 1 to 6 carbon atoms optionally substituted by 1 to 4 atoms of chlorine and/or fluorine, or a phenyl, tolyl and xylyl radical optionally substituted by 1 to 4 atoms of chlorine and/or fluorine. to Qg , which may be identical or different, have the same meaning as R^.

Rj = R‘2 is a methylene or ethylene radical.

X = X' is an atom of oxygen or sulphur or one of the radicals -0-C , —N— and -CON- , υ ι ι 0 r4 r4 R^ being hydrogen or a methyl or ethyl group. Γ = Γ1 is an alkylene or alkylidene radical having from 1 to 6 carbon atoms, a cyclohexylene radical, a phenylene, tolylene, xylylene or bensylene radical, a radical formed by two phenylene groups linked to one another by the valency bond or by an alleylene or alkylidene group having from 1 to 4 carbon atoms , an oxygen atom or a -NH-, -SOj-> —C— or -C-NH- group it It 0 Γ = f is a 1,2,4-bensenetriyl radical or one of the following radicals: R represents an alkylene radical having from 1 to 8 carbon atoms, a cyclohexylene radical, a phenylene radical, a tolylene radical, a xylylene radical, a divalent radical containing 2 to 4 phenylene groups linked to one another by a valency bond, by an oxygen atom or by the groups: O -C-, -SO--, -NH-, -P-, -C- and -CONH, II I and -CO-NH-. or an alkylene or alkylidene group containing from 1 to 4 carbon atoms, or a divalent radical containing 2 alkylene groups having from 1 to 4 carbon atoms linked to a phenylene group by a valency one of the groups II -C-, -SO2~, -NH-, -C-O-, R1 and R represent trivalent or tetravalent radicals containing 1 or 2 benzene nuclei linked to one another by a valency bond, an oxygen atom, a methylene radical, an isopropylidene radical or a bond,· by an oxygen atom or by -so2-, H —C— or group.

-PI n is between 10 and 200 and more particularly between 10 and 80.

T and Τ' represent one of the groups C0-COO-, CONH-, -NH-COO-, -NH-CO-NH- and -N/' -C0Y= -O-CO-OAs specific examples of compounds of the formulae (I) there may be mentioned those which contain a plurality of recurring units of the formulae: ?H3 ° θ CH3 Z?H3\ ^3 -$ί-σΗ2-ο-θ-α-ΝΗ-θ-θΗ2-θ-ι®-ε;-θ-ο-αι2-^ί- ( ch2 ) 4 si-o-siCH, ta, 'tn, ! CH, 3 3 325 3 CH, ,CH,. CH.

CH3 OH3 /Cii3\ GU H,) 2-Si-CH2-O-^-NH-CO-^-CONH-^-O-CH2-Si- (CH2) 2+Si-(»-Si“ CH, CH, I 3 CH. *2^2?^~CH2 CH, CH. ,CH.\ CH /—\ I 3 11 3\ I 3 °’^^~ra2~H^''CNH“CT2'W>“OCH2'Si(CH2)2rSiCr“ Si ' 0 ch3 'ch3/b4 £h3 1^3 CT3 13132> 2^i-^-O-O-C^-O-C-O-CHj-Q-O-^-Si-iC^) Jsi-A- Si CH, 0 CH, CH,/ CH, CH, j CH^ 0 -3ί-σΗ2-Ο-θ-ΝΗ-σ-ΝΗ-θ-σ-Ι2-θ-ΝΗ-Ο-ΝΗ-θ-Ο-σΗ2-3ϊ^ CH^ ksioj- si ' 11 U CH ' I CH CH, ,CHi CH, , 3 /1 A 1 Sx^CH^fsicA =< ‘3 CH/ CHJ 55 ώ -CH.

CgH5 CTU CH3 -O^C-O^CH^-O-C^C-O-CCH^-O-C-^OC^-k-iCE^/k-A -k CgHg '(2H3/4 CH3 CH. I 3 /CH, /c,HA CH. 3 /1 6 5\ j 3 •Oj -Si— taJ ch, 50 3 CH, Ο Ο O 0 CH, \CH, \CH - 21 42010 ΐΗ3 ™ ?Η3 Ζ?6Η5 ?6 (CH2 )3-|i-CH2-O-^J-COO- (CH2 ) 2-OCO-^_^-O-CH2-|i- (CH2) 34-^i-O-|i CH, CH, 'C-H_ C, , flJ7| C6H5 W f * 3 r-CCOx x-c<\ 2<fH-fi-CH2-O-O-OCO-0fcoZN-(CH2)6-N,co>v CH CH- \=/ CH-rCH CH, I 3 ch3ch3 OOCH2-Si(CH2)^ Si-Oj-Si CH, CH,/ <^H, 2000 CO G6H5 fH3 - (CH2) 5Si- (CH2) 2-000-<ζν^ ^N- (CH2) 6-NH-CO^J>-O-CII2-Si— (CH2) 24-Si-0j- Si— tn3 co cii3 'ch3/0ch3 C2H2F3 co CH3 /CH;-(0Η2)2-3χ -CH2-O^J-NHCOYY ^N-Q-O-CH2-Si-(CH2).

CO CII, z°\ CH, (CH2) 2-Si-CH2-O-^-NHCO-^0/ ^-θ-Ο-Ο^-δί- (CH2 <^η, co cH, CH, ™3 ,COX ,-. XCOS fH3 (CH2) 2-Si-CH2-oO-< N-0-a-CH2-hi-(CH2) CH, LU LU CH, CII, I .3 Sitil J CH, CO CH, CO CH, /CH, \ CH, ι 3 /—\ / \ ι 3 / \ ,—χ ι 3, Ζ ι 3 \ I 3 .(CH2)2-Si-CH2-O-Nx Orm N-O-0-CH2-^i-(CH2)2^i O VsiCII- CO CHC^ CO CH, \CH, / CH, 3 3 \ 3 /25 3 CH3 CO CH3 /CH, -(Ο^Ι^έχ-ΟΗ^Ο-^-ΝΗΟΟη^γγ ^N-Q-O-CH2|i-(CH2)2 Ui oi ___ / CO 0h, \ti: £%CN Si O tn C 3 2Ό CH' I 3> *SiI CH. - 22 *... 42Q10 ^>2 ? „ '?ΗΛ :H2Si-CH5O-^-C-NH-^-NH-C-^-O-CH2Si-CH2-CH9-Si—- ίΟ-Si -4-0-SiU«Oi —J— — < /13 J (CH,)_ 0 0 (CH,)„ (CH,)_(CH,),(CHJ, (32 μ /=\ ι, __ I 3 2 1,3/2 I \3 2 j 3< [^Si-CH^O-^-C-m-^-O-C-^-NH-C-^-O-O^-Si-CH^CHgSi—iO-Sil·—O-Si ' 28 Preparation of the thermoplastic elastomers with recurring units pf the formulae (I) The thermoplastic elastomers according to the invention can be obtained easily by reaction of at least one diethylenic silicon compound of the general formula ^1^2 ^'l^2 a-\-Si-R,-X- Γ-ψ- JP-X’ -R' .-Si-λ’R' (XIV) in which λ, Rr R2, X, Γ’ ,ψ , Τ' , X', R’2, R^ and λ’ have the meaning given above and R and R' are identical or different monovalent organic groups containing an ethylenic double bond and at most 10 carbon atoms, with at least one α,ω-dihydrogenopolysiloxane of the general formula: ?1 HJ—Si I Q.

(XV) optionally in the presence of customary catalysts for the reaction of compounds having = Si-H groups with ethylenic double bonds. The diethylenic silicon starting materials are described and claimed in Patent Specification No. · By way °£ example, this polyaddition reaction, which will hereafter be referred to as hydrosilyiation can be illustrated by the following scheme if R and R' represent a vinyl group and λ and λ1 represent a valency bond in the formula (XIV): ^’l’2 '-R'2-Si -CH=' <*1>2 CH.=CH-Si-R,-X-r-'j'- Γ'-Χ CII., + H· 2 x (Rp2 CH.-CH.-Si-R.-X-ΨΓ'-Χ',-R (R' ), /-/ CH2-CII2- In particular R and R' represent linear or branched alkenyl radicals optionally substituted by one or more atoms of halogens, especially of chlorine and/or of fluorine, or cycloalkenyl radicals optionally substituted by one or more atoms of halogens, especially of chlorine and/or of fluorine.

R and R* preferably represent linear alkenyl radicals having from 2 to 6 carbon atoms and more preferably still radicals with a terminalethylenic double bond.

As specific examples of radicals R and R' there may be mentioned the following radicals: vinyl, allyl, prop-2—en-l-yl, prop-2-en-2-yl, but-3-en-l-yl, but-2-en-l-yl, but-l-en-l-yl, pent-220 en-l-yl, pent-2-en-2-yl, pent-4-en-l-yl, pent-4-en-2-yl, hex-5-en-l-yl, oct-7-en-l-yl, α-chlorovinyl, α,βdichlorovinyl, a, (i-difluorovinyl, cyclohex-3-en-l-yl and - 24 43610 cyclohex-2-en-l-yl.

A. Conditions of the polyaddition reaction The reactipn of the compound (XIV) with the compound (XV) can he carried out under the conditions usually employed during the addition of compounds having s Si-H groups with ethylenic compounds, cf. W.NOLL, Chemistry and Technology of Silicones (1968)', pages 49 et seq.

Thus, the hydrosilylation reaction can be carried out by heating the reactants at, for example, 150 to 350°C under autogenic pressure in the absence of catalysts. It can also be carried out in the presence of the customary catalysts, which makes it possible to use less high temperatures, of the order of 0 to 200°C, and allows the reaction to take place more rapidly under normal pressure.

As catalysts, compounds which generate free radicals are suitably used, such as peroxidic compounds (for example acyl peroxides, alkyl peroxides and per-esters) or azo compounds. As illustrations of these compounds there may be mentioned benzoyl peroxide, acetyl peroxide, lauroyl peroxide, t-butyl perbenzoate, t-butyl peracetate, t-butyl peroxide and N,N'~ azobis-isobutyronitrile. The same effect can be achieved if the process is carried out under ultraviolet irradiation instead of carrying out the reaction in the presence of catalysts which generate free radicals.

Another group of catalysts which can be employed to prepare the thermoplastic elastomers of the invention consists of the metals of group VIII of the periodic classification of the elements (cf. - 25 42610 Handbook of Chemistry and Physics, 53rd edition) and their inorganic or organic derivatives. Amongst these metals tjiere may in particular be mentioned Pt, Ru, Rh, Pd and Ir. The noble metals are particularly suitable,, and platinum is very specially suitable. They can be used in the form of the element or in the form of salts of inorganic acids, in particular halides, salts of organic acids or complexes. Such catalysts have been described in the literature, cf., for example, U.S. Patents Nos. 2,637,738 and 2,632,013: J.L.SPEIER et al., J.Am. Chem. Soc. 79, page 974 et seq. (1957); A.J.CHALK et al., J.Am. Chem. Soc. 87, 16 (1965).

Amongst these catalysts based on metals of group VIII, those based on platinum are very particularly suitable and are preferably employed.

They can assume various forms which are well-known in the technical literature. Thus, it is possible to use the various catalysts based on finely divided elementary platinum which may or may not be deposited on various supports such as carbon black, alumina and silica; catalysts of thi 3 type have in particular been described in U.S. Patent No. 2,970,150. Another family of platinum catalysts consists of chloroplatinic acid (cf. U.S. Patent No. 2,823,218) and the compounds derived therefrom, such as alkali metal chloroplatinates (cf. J.L. SPEIER, loc. cit); and compouncfe obtained by reaction of chloroplatinic acid with alcohols, ethers or aldehydes (cf. U.S. Patent No. 3,220,972), with olefines (cf. U.S. Patent No. 3,159,601) or with cyclopropane (cf. U.S. Patent No. 3,159,662). It is _ 26 43610 also possible to use the complexes of platinum halides with compounds which are donors of electron pairs, such as the phosphines, for example bis-(tributylphosphino)dichloroplatinum (XI) and bis-(triphenylphosphino)dichloroplatinum (II) (cf. A.J. CHALK et al., loc. cit). Elementary platinum deposited on charcoal and chloroplatinic acid and its derivatives are the platinum catalysts preferably used in the process of this invention.

The hydrosilylation reaction can be carried out in the absence of a solvent or by bringing the reactants and, if appropriate, the catalyst, into contact in an organic medium consisting of a solvent or a diluent which is inert under the reaction conditions.

As such, there may especially be used saturated aliphatic hydrocarbons such as pentane,· hexane and heptane; saturated cycloaliphatic hydrocarbons such as cyclohexane; aromatic hydrocarbons, such as benzene and toluene; halogenated hydrocarbons, such as chloroform, diehloroethane and chlorobenzene; alcohols such as ethanol, propanol and isopropanol; ethers, such as tetrahydrofurane; and esters, such as methyl acetate, ethyl acetate and butyl acetate. The choice of the reaction medium depends on the nature of the starting reactants and on the temperature at which the reaction takes place. The reaction can take place in solution or in suspension depending on whether one or' both reactants are soluble or insoluble in the chosen medium.

The relative amounts of the compounds of the formula (XIV) which will hereafter be referred to as dialkenylsilane monomer or dialkenylsilane and - 27 42510 and of the α,ω-dihydrogenopolysiloxane, which will hereafter be referred to as dihydrogeno monomer”, can vary within wide limits. Thus, the relative amount of the reactants, expressed by the ratio of the number of alkenyl groups introduced by the dialkenylsilane monomer to the number of active hydrogen atoms introduced by the dihydrogeno monomer can vary, for example from 2 to 0.5. However, to obtain polymers of high molecular weight it is preferable that the ratio defined above should be close to 1, through a slight excess of one or other of the reactants can be used. Thus the ratio of alkenyl group/H is preferably from 1.2 to 0-8. Xn this case the molecular weight of the thermoplastic elastomer of the invention, can, where necessary, be adjusted to the desired value by using a chain stopper consisting of a silicon compound containing a single a Si-H group or consisting of an organic or organo-silicon compound containing only one ethylenic double bond.

Though any compound having a = Si-H group can be used as the chain stopper, the following are particularly suitable; trimethylsilane, triethylsilane, tri-n-propylsilane and diethylmethylsilane.

Amongst the chain stoppers having an alkenyl group, organo-silicon compounds such as trimethylvinylsilane, triethylvinylsilane and allyltrimethylsilane are preferably used, though it is possible to use organic mono-unsaturated compounds such as vinyl acetate, styrene or allyl benzene.

The amount of chain stopper is decided as a function of the desired molecular weight of the 43610 thermoplastic elastomer, in accordance with the rules well-known in polymer chemistry to those skilled in the art.

If a catalyst is used to carry out the hydrosilylation reaction, the amount employed can vary within very wide limits depending on the nature of the catalysts, the nature of the reactants employed and the reaction conditions.

Where a compound which generates free radicals is used, it is possible to use, for example, from -4 x 10 to 0.1 mol of catalyst per mol of dialkenylsilane monomer, though it is possible, without disadvantage, to go outside these limits.

If the catalyst is one of the abovementioned metals or a derivative of these metals, especially platinum, the amount of catalyst, expressed as gram atoms of metal per alkenyl group present in the dialkenyl monomer is suitably from 10 ® to 10-^ gram atom of metal per -5 -2 alkenyl group and preferably from 10 to 10 As has already been indicated, the reaction temperature can vary within wide limits depending on whether the reaction is carried out in the presence or absence of a catalyst or, in the former case, depending on the nature and amount of catalyst employed. Overall, the temperature can vary e.g. from 0 to 300°C and preferably from 20 to 250°C. The use of platinum catalysts makes it possible to work at temperatures of the order of 10 to 200°C. The reaction can also be carried out at a pressure above, below or equal to atmospheric pressure.

To prepare the thermoplastic elastomers of the formula (I) in which R“ is an 43610 arylene radical containing one or more functional groups such as specified earlier, it is preferable to employ compounds of the formula (XIV) in which the functional groups carried by the arylene radicals R are inert towards the dihydrogenosiloxane under the reaction conditions. To obtain compounds of the formula (I) in which R represents an arylene radical substituted by a functional group capable of reacting with the dihydrogenosiloxane (for example an amine group), a compound of the formula (XIV) is employed, in which the functional group or groups carried by the arylene groups R are blocked by inert groups and are then liberated by treating the polymer obtained after hydrosilylation (for example by hydrogenation of nitro groups to amine groups , in a known manner).

B. Monomers employed in the polyaddltion reaction 1. The dialkenylsilane monomers of the formula (XXV) are compounds which can be prepared by reaction a) of an organosilicon compound of the formula: R-X-Si-Rj-X-T-Y (XVI) by itself or together with a compound of the formula: R' - λ' - Si - R'2 - X' - f - Υ' (XVII) with Cl-C-Cl b) a coupling agent of the formula: A * T.-R''-R'. Tj-R'' 0 II II 0 0 II c 0 or o; ^R1xc II 0 0 H (XVIII II o 1 1 in which: R, R. , , X, Γ, R', R' 1 · R'o , X', Γ1, λ and λ' have 42Q10 the meaning given above and Y and Y' represent the following -COORg (a) -COCI (b) -NH »4 (c) -OH (d) -SII (e) -NCO (f) when Γ or Γ’, respectively, is divalent, or 0 II IS -C-O-C- (g) when tor Γ1, respectively, is trivalent, wherein R^ has the meaning already given and Rg represents a hydrogen atom or an alkyl, radical containing from 1 to 4 carbon atoms, such as methyl, ethyl, propyl and butyl.

The radicals R, R' and R are as defined for the formulae (VII) to (IX).

Tj- and T'j_, which may be identical or different, represent a chlorine atom or one of the groups defined for Y and Y1 or additionally a valency bond when T^-R-T^' represents Cl-C-C-Cl or R.-O-C-C-OR._ ιί ιι XV π κ -Lu O O 0 0 4 2 610 The preparation of the dialkenylsilane monomers, which is described and claimed in Patent Specification No. to which reference should be made, by reaction of the compounds of the formulae (XVI) and (XVII) with the difunctional compounds (XVIII), can be carried out by employing tlie general principles of chemistry well known to those skilled in the art regarding the reaction of acids or their derivatives (chlorides, anyhydrides and esters) with alcohol, thiol, amine and isocyanate groups, or of the reaction of isocyanate groups with alcohol, amine or thiol groups.

Preparation of the compounds XVI and XVII The functional monoalkenylsilane compounds of the formulae (XVI) and (XVII) used to prepare the dialkenylsilane monomers can be obtained according to a process which comprises reacting a compound of the formula: (R, ), I12 R - Si Cl (XIX) in which R, R^ and R2 have the meanings already given, with a compound of the formula: Z - X - J? - Υχ (XX) in which: X and T have the meanings already mentioned and Z represents a hydrogen atom, an alkali metal such as Na, K or Li or a quaternary ammonium group of the formula (RgJ^-NH-, wherein Rg has the meaning already given for the group (a), and Y has the meanings given for Y and Y* in formulae (XVI) and (XVII) and can furthermore be' a functional group which is a precursor of Y and Y’, such as the groups: -N02, Rg-C-O-, —ORg, -S-Rg, Rg-C-S-, -C0NH2, -CN ot O O -CHO, wherein Rg has the meaning already formulated.

If X represents an oxygen atom, a sulphur atom or a carboxyl or thiocarboxyl group, 2 is preferably a sodium or potassium or lithium atom or an ammonium group t(Rg)3NH}-. For convenience, the alkali metal salts and the tertiary amine salts of acids or of phenols have been represented by a formula which uses covalent bonds. Obviously these compounds can also be employed in the ionic form.

It is obvious that the group Y^ must be inert under the conditions of the condensation reaction of’the compound (XIX) with the compound (XX) and that a group Y^ which is not prone to react either with the chlorine of the compound (XIX) or with the group Z-X- of the compound (XX) will be chosen. Those skilled in the art will in the same way suitably choose the groups Y^ by applying the general laws of chemistry.' If Y^ is a precursor of the groups Y, the compound with the group Y'will be obtained by conversion of Y^ by means of the usual reaction such as hydrogenation, hydrolysis and saponification.

By way of indication, if Z - X - represents a group 42Gt Ο containing an alkali metal atom ot a quaternary ammonium group, Y^ can be one of the following functional groups: -NO -NH, -CO-NH, and -CN. *4 If Z - X - represents an amino group, the group Y^ can be -NO., -O-C-R., -COOR., -OH, -OR., -S-C-R., y 6 6' 6' || 6' 0 -SH, -SRg, -CONH2 and -CN.

The organosilicon compounds (XIX) can be obtained in accordance with the general methods for obtaining organosilicon derivatives with chloroalkyl groups (see our Patent Specification No. 2116/75). For this purpose, it is usual to prepare chloroalkylchlorosilanes which are converted by a Grignard synthesis into the corresponding ethylenic organosilicon compounds. These methods are described, for example, in the treatise by Eaborn: Organosilicon compounds, pages 379-381 (I960).

Purely by way of illustration, the following compounds may be mentioned amongst the organosilicon compounds (XIX):vinyldimethylchloromethylsilane, allyldimethyIchloromethylsilane , vinyldiphenylchloromethylsilane, allyldi20 phenylchloromethylsilane, vinyldimethylchloroethylsilane, vinyldimethylchloropropylsilane, but-l-enyl-dimethylchloromethylsilane, 1,2,2-trichlorovinyl-dimethylchloromethylsilane, vinylmethyIphenyIchloromethylsilane, γ-cyanopropylvinylmethylchloromethylsilane, and 1,1,3,3-tetramethyl-3-vinyl25 1-chloromethyl-disiloxane.

The compounds of the formula (XX) can be amine compounds such as p-ethoxycarbonylphenyl-methylamine, p-nitro- 34 43610 phenylmethylamine, and 4-li-methylamino-4‘-nitro-diphenylmethane, or alkali metal salts or tertiary amine salts of carboxylic acids, such as p-methoxybenzoic acid, the monoethyl ester of terephthalic acid, the monomethyl ester of diphenylmethane-4,4'-dicarboxylic acid, p- or m-nitrobenzoic acid,3,4-dinitrobenzoic acid and p-nitrothiobenzoic acid.

These compounds (XX) can also be alkali metal alcoholates to thiolates such as the salts of the following compounds: methyl p-hydroxybenzoate, p-hydroxynitrobenzene, 4-hydroxy-4'-nitro-diphenylmethane, 4-hydroxy-4'-ethoxydiphenyl ether, ethyl 4-mercaptobenzoate, 4-mercaptonitro-benzene, 4-mercapto-ethoxybenzene, the ethyl ester of thioglycollic acid and the methyl ester of 4-hydroxybutanoic acid.

The condensation reactions of the organosilicon compound (XIX) and the compound (XX) can be carried out in accordance with the general processes described in the literature and by reference to the nucleophilic substitution reactions which employ an organosilicon compound with a chloroalkyl group [see e.g. Eaborn: Organosilicon compounds pages 393, 411, 412 and 413 (196(3) and U. S. Patents Nos. 2,783,262, 2,783,263 and 2,833,802].

The following may be mentioned as examples of compounds (XVI) or (XVII) employed, for the preparation of the dialkenylsilanes of the formula (XIV): l-Amino-4-(vinyldimethylsi)y)methoxy)-benzene, 1hydroxy-4-(vinyldimethylsilylmethoxy)-benzene, l-mercapto-4(vinyldimethylsilymethoxy)-benzene, l-carboxy-4-(vinyldi- 35 4 2(510 methyls ilylmethoxy)-benzene, 4-(vinyldimethylsilylmethoxy)benzoic acid chloride, l-methoxycarbonyl-4~(vinyldimethylsilylmethoxy)-benzene, l-isocyanato-4-(vinyldimethylsilylmethoxy)-benzene, l-amino-4-(2-vinyldiinethylsilyl-ethoxy)benzene, l-hydroxy-4-(2-vinyldimet.hylsilyl-ethoxy)-benzene, l-amino-4-(3-vinyldimethylsilyl-propoxy)-benzene, 1-mercapto4-(3-vinyldimethylsilyl-propoxy)-benzene,1-amino-4-(vinyldimethylsilylmethoxycarbonyl)-benzene,l-carboxy-4-(vinyldimethylsilylmethoxycarbonyl)-benzene, l-amino-4-(vinyldimethylsilylmethylthio)-benzene, 1-ethoxycarbonyl-4-(vinyldimethylsilylmethylthio)-benzene, l-ethoxycarbonyl-4-(vinyldimethylsilylmethylthiocarbonyl)-benzene, l-ethoxycarbonyl-4(vinyldimethylsilylmethylthio-thiocarbonyl)-benzene, 4-vinyldimethylsilylmethoxy-4‘-amino-diphenylmethane, 4-vinyldimethylsilylmethoxy-4'-chlorocarbonyl-diphenylinethane, 4-vinyldimethylsilylmethoxy-4'-amino-diphenyl ether, 4-vinyldimethylsilylmethoxy-4’-methoxycarbonyl-diphenyl ether, 4-vinyldimethylsilylmethoxy-41-amino-diphenylsulphone, 4~vinyldimethylsilylmethoxy-4'-amino-diphenyl, 4-vinyldimethylsilylmethoxy-4'-hydroxy-diphenyl, 4-vinyldimethylsilylmethoxy-4'chlorocarbonyl-diphenyl, l-amino-4-(allyldimethylsilylmethoxy)benzene, l-amino-4-(but-l-enyl-dimethylsilylmethoxy)-benzene, l-amino-4-(methyldivinylsilylmethoxy)-benzene, l-amino-[(1,2,2trichlorovinyl )-dimethylsilylmethoxy]-benzene, l-amino-4(vinyldiphenylsilylmethoxy)-benzene , l-amino-4-[vinyl-bis(3,4-dichlorophenyl)-silylmethoxy]-benzene, l-amino-4(methylphenylvinylsilylmethoxy)-benzene, l-amino-4-(methylγ-cyanopropylvinylsilylmethoxy)-benzene, N-p-aminophenyl-N- 36 42610 vinyldimethylsilyImethyl-methylamine, N-p-ethoxycarbonylphenyl-N-vinyldimethylsilylmethyl-methylamine, the ethyl ester of 4-(vinyldimethylsilylmethoxy)-butanoic acid, 4-vinyldimethylsilylmethoxy-butylamine, 3-amino-5-(vinyldimethylj silylrnethoxy)-pyridine, 3-ethoxycarbonyl-5-(vinyldimethylsilylmethoxy) -pyridine , l-amino-4-[ (dimethylvinylsiloxy)dimethylsilylmethoxy]-benzene, l-aminomethyl-4-(vinyldimethylsilylmethoxy- (benzene, l-hydroxymethyl-4-(vinyldimethylsilylmethoxy-bensene,the ethyl ester of 2-(vinyldimethylsilyl3 methyl)-thioglycolic acid, l-amino-4-(methyl-γ-trifluoropropyl vinylsily Imethoxy) -benzene and 4-(vinyldimethylsilylmethoxy) -phthalic anhydride.

Amongst the difunctional compounds of the formula (XVIII) which cah be used for the preparation of the dialkenylsilane monomers there may be mentioned: phosgene, dicarboxylic diacids (or their esters, their anhydrides or their chlorides) such as oxalic acid, succinic acid, glutaric acid, adipic acid, dodecanedioic acid, 1,4-cyclohexanedicarboxylic acid, o-phthalic acid, terephthalic acid, 1,5-naphthalenedicarboxylic acid, 4,4'-diphenyldicarboxylic acid and the oxide of phenyl-bis(4-hydroxycarbonyl-phenyl)phosphine, diamines such as hexamethylenediamine, ethylenediamine, bis-(4-aminocyclohexyl)-methane, 1,4-diaminccyclohexane, bis-(4-aminophenyl)-methane, 2,2-bis-(4-aminophenyl):5 propane, 4,4'-diaminodiphenyl ether, m-phenylenediamine, pphenylenediamine, 4,4'-diaminodiphenyl sulphide and the oxide of bis-(4-aminophenyl)-phenyl-phosphine, diisocyanates such as 1, 2-diisocyanatopropane, 1,2-diisocyanatobutane, - 37 1.3- diisocyanatobutane, 1,6-diisocyanatohexane, 1,3-diisocyanatobenzene, 1,4-dissocyanatobenzene, 2,4-diisocyanatotoluene, 2,6-diisocyanatotoluene, 2,4-diisocyanatoxylene, 2,6-diisocyanatoxylene, 3,3'-d.iisocyanatodiphenyl, 4,4'5 dii3ocyanatodiphenyl, 3,3'-diisocyanatodiphenylmethane, 4,4'diisocyanatodiphenylmethane, 4,4'-diisocyanato-3-31dimethyldiphenyl, 4,4'-diisocyanato-3,31-dimethyldiphenylmethane, 4,4'-diisocyanatodiphenylethane, 3,31-diisocyanatodiphenyl ether, 4,4'-diisocyanatodiphenyl ether, 3,3'10 diisocyanatodiphenylsulphone, 4,4'-diisocyanatodiphenylsulphone, 3,3'-diisocyanatobenzophenone, 4,4'-diisocyanatobenzophenone, 3,3'-diisocyanatodicyclohexylmethane, 4,4'diisocyanatodicyclohexylethane, L,5-diisocyanatonaphthalene, 4,4'-diisocyanato-3,3 ‘-diclilorodiphenyl, 4,4'-diisocyanato15 3,3'-dimethoxydiphenyl, diols and diphenols such as ethylene glycol, diethylene glycol^ triethylene glycol, tetraethylene glycol, 1,3-propanediol, 1,2-propanediol, 1,4butanediol, 1,3-butanediol, 1,5-pentanediol, 1,4-pentanediol, 1.3- pentanediol, 1,6-hexanediol, 1,7-heptanediol, bis-(β— hydroxyethyl) terephthalate, hydroquinone, 4,4'-dihydroxydiphenyl , bis-(4-hydroxyphenyl)-methane, 2,2-bis(4-hydroxyphenyl) -propane, 4,4'-dihydroxydiphenyl ether, bis-(4hydroxyphenyl)-sulphone and the oxide of bis-(4-hydroxyphenyl)phenylphosphine, dithiols such as 1,2-ethanedithiol, 1,325 propanedithiol and 1,4-dimercaptobenzene, aminoacids, aminoalcohols, aminophenols and acid-alcohols such as 6-aminocaproic acid, 6-hydroxycaproic acid, ethanolamine, 6-aminohexanol and p-hydroxyaniline, and tricarboxylic or tetra38 J 3 6 10 carboxylic acids (or their anhydrides or chlorides) such as trimellitic acid, 3,4,4’-tris-hydroxycarbonyl-diphenyl, 4-hydroxycarbonyl-diphenyl ether and 3,4’-di(hydroxyc.arbonyl)-diphenyl ether, 4,3,4'-trihydroxydiphenylsulphone, pyromellitic acid and 3,4,3',4'-diphenyltetracarboxylic acid.

As specific examples of dialkenylsilane monomers of the formula (XIV) which can he employed for the preparation of the silicon-based thermoplastic elastomers there may be mentioned the conpounds of the formulae: ^3 π π ?H3 :2=CH-Sx-CH2-0-^y-CH2-0-^-0-CH2-^-0-CH2-|i-CH=CH2 (1) ch3 0 ch3 CHCH.

I2=CH-Si-CH2-0-^-CH2-NH-C-NH-CH2-^^-0-CH2-^i-CH=CH2 CH- 0 CH. (2) CH.

CH. 12=CH-Si-CH2-O-+^ —O-CHj-Si CH. 0 O (k-Si-CH=CH_ (3) CH. 32=CH-Si-CH2~O-^4) -C-NH- -CH2-^^—NH-C-£j^ -0-CH2-Si-CH=CH2 (4) CH. O 0 ck.

CH.

CH.

H2=CH-Si-CH2-O-^^-NH-C-NH-^>-CH2-^-NH-C-NH-^y-O-CH2-Si-CH=CH2 (5 CH.

CH.

CH. :2=CH-Si-CH2-O^-C-O-CH2-O-C-Q-2-aC-Q-O-CH2-SiCH_ OOO 0 CH.

Si-CH=CH(6 43610 CH2=CH· fH3 •fi-CH, CH. (7) CH. CH. | 3 | 3 CH2=CH-Si-CH2-O-2-CH2-O-C-/_7-O-CH2-Si-CH=CH2 (8) ch3 ” o & ch3 CH.

I 3 CH.=CH~Si-CH.-O-C2 I 2 II ch3 0 CO. -'co/ N- (CH.) .-NH~C-/~Vo~CH.-Si-CH=CH.

II \=/ 0 CH. (9) CH2=CH-Si-CH2-O-^^-NH-C-^rj/Z O-CH2-Si-CH=CH2 CH. 0 / ~ CH.

C J ί (10) H3 CH2=CH-Si-CH2- o-^2^-nh-c CH.

CO, CH.

CH.

KN— (/ CH.-Si-CH=CH„ ι 2 CII.

(ID CH2=CH-Si-CH2-O-^2^-NHCH.

O-CH CH. i-CH=CH. f1 CH. {12; - 4o 42610 2. The «-ω-dihydrogenopolysiloxanes of the formula (XV) employed as comonomers for the preparation of the thermo-plastic elastomers are known products obtainable in accordance with the (20) - 41 42G10 usual processes of the chemistry of the silicones.

For example, it is possible to hydrolyse the monohalogenodiorganosilane, such as monochlorodimethylsilane, or cohydrolyse a monohalogenodiorganosilane, a dihalogenodiorganosilane and/or a cyclic polydiorganosiloxane such as octamethylcyclotetrasiloxane; it is also possible to react a monohalogenodiorganosilane with an α,ω-dihydroxypolysiloxane having a high or low molecular weight or an a,ω-dialkoxypolysiloxane; further, it is possible to react a dihydrogenodiorganosiloxane with an a,ω-dihydroxy polysiloxane or an a,ω-dihalogenodiorganosiloxane with a metal hydride such as lithium aluminium hydride.

They can also be obtained by cationic polymerisation of an octaorganocyclototra3iloxane such as octamethylcyclotetrasiloxane with an α,ω-dihydrogenomonosiloxane such as α,ω-dihydrogenotetramethylsiloxane.

The molecular weight of the α,ω-dihydrogenosiloxane of the formula (XV) is determined by the value of n, which can vary from 0 to 2,000. In general, compounds in which n is from 3 to 500 and preferably from 10 to 200 and especially from 10 to 80 are used.

The a,w-dihydrogenopolysiloxane can be a homopolysiloxane or a copolymer derived from two or more dihalogenodiorganosiloxanes. The copolymers can be either compounds in which the various units are arranged at random or block copolymers.

As specific examples of compounds of the formula (XV) there may be mentioned: dihydrogenotetramethyldisiloxane, dihydrogenodiethyldimethyldisiloxane, dihydrogenodiphenyldimethyldisiloxane or the compounds of the formula: - 42 42610 H(CH3)2 - Sio[CH3C6H5SiO^Si(CH3)2H H(CH3)2 - Sio[ (C-H5)2-Si0]]si(CH3)2H H(CH3)2 - SiO[(CH3)2-Si0|si(CH3)2H H(CH3)2 - Sio[(CH3)2-SiO^?0 Si(CH3)2H H(CH3)2 - SiQt(CH3)2-SiO^ Si(CH3)2H H(CH3) {C6H5)Siot(CH3) (C6H5)Sio3y^ Si(CH3) (Cgl^H H(CH3) (C3H4F3)Si0£- (CH3) (C3H^F3)SiQ-^Si(CH3) (C3H4F3)H H(CH3)2SiO-£(CgH^Cl)(CH3)SiO -^SitCH^H and H(CH3)2-SiO-G(C2H^CN)(CH3)SiO SKCH^H To prepare the thermoplastic elastomers according to the invention it is possible, as has alreadybeen mentioned above, to employ one or more dialkenylsilane monomers (XIV) together with one or more α,ωdihydrogenopolysiloxanes (XV). In the latter case it is possible to react 2 or more than two monomers (XIV) or (XV). This gives copolymeric thermoplastic elastomers.

It is also possible to obtain block copolymers by reacting a thermoplastic elastomer containing a plurality of recurring units of the formula (I) and having, at each end of the chain, a monoalkenylsilane unit or a hydrogenosiloxane unit, with a thermoplastic elastomer containing a plurality of recurring units of the formula (I) different from those of the first elastomer and terminated by hydrogenosiloxane or monoalkenylsilane unit, respectively.

The thermoplastic elastomers according to the invention can be used in essentially all the fields where - 43 42610 silicone elastomers are conventionally used, as they retain the properties of the iattor, but also in other fields which are those where thermoplastic polymers are used because of the ease with which they may be employed. They can be converted into various moulded articles by extrusion or injection in the molten state, or by stamping. They are particularly suitable for the production of films or of fibres. They can also be converted into finished articles by starting from their solutions in organic solvents.

Before being used, the thermoplastic elastomers according to the invention can be mixed with the usual additives such as pigments, fillers such as the various types of silica, titanium oxide and carbon blacks, plasticisers or heat stabilisers and light stabilisers.

The following Examples further illustrate the present invention; all temperatures are given in degrees Centigrade. - 44 42610 EXAMPLE 1 1) Preparation of the thermoplastic elastomer 419 g of toluene, 108.14 g of an CH. CHi 3 _ _ _ | 3 CH2=CH-Si-CH2-0-^^-CONH-^^-CH2-^^-NHXO-^^-0-CH2-Si-CH=CH2 ch3 ch3 610 are introduced into all cylindrical glass reactor equipped with a stirring system, a heating device, a thermometer and a reflux condenser.

The contents of the reactor are stirred under a nitrogen atmosphere and then heated under reflux until a homogeneous solution is obtained. 3.3 cm of a solution containing chloroplatinic acid (HjPtClg) in isopropanol «•6 3 (concentration; 3 x 10” gram atom of Pt/cmJ) are then added. An immediate increase in the viscosity of the reaction mixture is observed. The mixture is kept under these conditions for 4 hours and the toluene solution is then cooled to 20°C.

The viscosity of the solution, adjusted to 20% by weight of solids content by addition of toluene, is 30 poises at 25°C.

A film is prepared by depositing, by means of a casting machine, a uniform 0.5 mm layer of the solution of 25% solids content on a glass plate and then evaporating the solvent by heating to 80°C for 1 hour. A transparent elastic film of 70μ thickness is obtained, the mechanical properties of which are as follows: breaking load determined in accordance with French 2 Standard SpecificationT 46,002: 88 kg/cm elongation at break determined in accordance with French Standard Specification T 46,007: 660%.

A sample of the film obtained above is dissolved in chloroform at a concentration of 0.5 g/100 cm . The inherent viscosity of this solution, measured at 25aC, is 65 cm3/g. - 46 43610 The examination, .by infra-red spectrometry, of the product obtained makes it possible to establish the absence of a band at 10.5μ which corresponds to the ssi-CH=CH2 group and the presence of the following bands: 3.05μ, corresponding to the -NH- group 6.10u, corresponding to the -C- group and It 6.64ju, corresponding to the -C-NH chain unit.

Furthermore, it was not possible to determine the active hydrogen by gasometric methods after treating the ) product with potash.

The polymer obtained above has a softening point of 160°C and a weight-average molecular weight Mw of 170,000, measured by light-scattering on a solution in ethyl acetate; it corresponds to the recurring structure.

(?H3}2 (CH ) I 3 2 (cn3)? 0-CH_-Si-CH_-CH -Si(OSi-)— 2 2 2 I 28 (CH ) . 3 2 ; —0-Si -i (ch3) 2) Preparation of 4,4l-N,Nl-bis-rp-vinvIdimethylsilylmethoxy)-benzoyl1-diamino-diphenylmethane 65.5 g of 4,41-diaminodiphenylmethane, 350 cm of chloroform and 74 g of triethylamine are introduced into a ) 500 cm flask equipped with a stirrer system, a reflux condenser, a dropping funnel and a thermometer.

The contents of the flask are cooled to 0°C whilst stirring and 168 g of p-(vinyldimethylsilyImethoxy)-benzoyl chloride are added slowly over the course of 1 hour 30 minutes - 47 42610 maintaining the temperature O’C.

The reaction mixture is added to 400 cm of distilled water. The organic· layer is separated off, washed with 3 times 200 cm of water, then dried over 5 anhydrous Na2S04 and evaporated to constant weight.

This gives 219 g of a crude product which is treated with carbon black and recrystallised from 500 cm3 of anhydrous ethanol. 171 g of 4,4'~N,N'-bis[p-(vinyldimethylsilyImethoxy)-benzoyl]-diamino10 diphenylmethane of melting point 154°C are thus obtained.

The percentage composition corresponds to that of the compound of the formula: CH. CHI 3 . I 3 CH2=CH-Si-CH20-^-CO-NH-^-CH2-^-NHCO-^-O-CH2-Si-CH=CH2 3) Preparation of p-(vinyldimethylsilvlmethoxv)15 benzoyl chloride 760 g of methyl p-hydroxybenzoate and 850 cm of Nmethylpyrrolidone are introduced into a flask and a methanolic solution of sodium methylate, prepared from 960 g of methanol and 115 g of sodium, is run in over the course of 2 hours 20 minutes at between 82 and 100°. The methanol is then removed by distillation and 672 g of vinyldimethylchloromethylsilane are run over the course of 1 hour 5 minutes at between 108 and 128°.

After distilling the N-methylpyrrolidone, the - 48 42610 distillation residue is taken up with 2 1 of cyclohexane and washed with water, and the methyl p-(dimethylvinylsilylmethoxy) -benzoate is rectified. This gives 1,136 g of a fraction of boiling pointy 110-113°, having a melting point of 25.5°.

Treatment of the methyl p-(dimethylvinylsilylmethoxy) benzoate with a sodium hydroxide solution containing 100 g of sodium hydroxide, 250 g of water and 1,000 cm of methanol gives the sodium salt of p-(dimethylvinylsilylmethoxy)-benzoic acid.

After acidifying a solution containing the sodium salt of p-(dimethylvinylsilylmethoxy)-benzoic acid, a white product melting at 118° is isolated by filtration; it corresponds to p-(dimethylvinylsilyImethoxy)-benzoic acid; 354 g of the acid previously prepared are introduced into a flask and 357 g of thionyl chloride are run in over the course of 40 minutes at between 28 and 29°.

The reaction mixture is then heated and kept at 102° for 1 hour. Rectification gives a fraction pf 344 g, of boiling pointQ 126-127°, corresponding to p(dimethylvinylsilylmethoxy)-benzoyl chloride.

EXAMPLE 2 A thermoplastic elastomer of the same structure as in Example 1 is prepared by following the same procedure bdt replacing the toluene by 476 cm of butyl acetate. The total duration pf the reaction is 5 hours.

The solution obtained, diluted to 20% by weight of solids by addition of butyl acetate, has a - 49 42610 viscosity of 2 poises at 25°C.

The inherent viscosity of a sample of the reaction product measured on a solution of 0.5 g in 100 3 cm of chloroform at 25°C is 53 cm /g.

The polymer thus obtained has a softening point of 160°C. The breaking load and the elongation measured 1 2 as in Example 1 are respectively 68 kg/cm and 600%.

The percentage analysis and the infra-red spectrum correspond to the product of Example 1.

EXAMPLE 3 1) Preparation of the thermoplastic elastomer with recurring units? (CH3)2 (CH3)2 (0Η3)2(0Η3)φ}2 CH^-CHA-Si-CHo-0--NH-C0-?-Si-CH2-GH2-Si-(0-3)-0-Si4.088 g of N,N‘-bis-[p-(vinyldimethylsilylmethoxy)15 phenylj-terephthalamide, 8.36 g of an cc, ω-dihydrogenopolydimethylsiloxane of number-average molecular weight 1,114, containing 0.181 atom of active hydrogen per 100 g of polymer, having a visc/bsity of 9.3 cst at 25°C, and containing about 3 dimethylsiloxane units, and 43 cm of toluene are 20 introduced into a reactor equipped as in Example 1.

The contents of the reactor are heated to the reflux temperature and 0.36 cm^ of a solution of chloroplatinic acid containing 8 x 10- gram atom of Pt/cm is then added.

The terephthalamide dissolves in 7 minutes. A further 43610 0.90 cm of chloroplatinic acid is added and heating is continued for 5 hours 30 minutes. The solution is very viscous; cooling gives a gel which is dispersed in 200 cm of methanol and stirred vigorously. The polymer obtained 3 is filtered off and then re-suspended in 200 cm of methanol. It is then filtered off and dried at 80°C under mm of mercury.

This gives a product of softening point 190 °C and q of inherent viscosity 32 cm /g, measured at 25 °C on a solution of 0.5 g in 100 cm3 of CHCl^.

The percentage composition and the infra-red spectrum correspond to those of a polymer having the recurring unit mentioned above. It was not possible to demonstrate the presence of active hydrogen which can be determined by gasometric methods after treating the product obtained with potash. The infra-red spectrum of the product no longer contains the bands characteristic of the vinylsilyl group.

A sample is moulded by using the following procedure: g of the polymer obtained above are introduced into a square mould of size 10 x 10 x 0.4 cm and the mould is placed between 2 sheets of stainless steel. The whole is placed between the platens of a press heated to 194°C, a pressure of 15 kg/cm is then applied and the whole is kept under these conditions for 15 minutes.

After cooling, a transparent elastic sheet is obtained, the mechanical properties of which are as follows; breaking load determined in accordance with French Standard Specification T 46,002: 141 kg/cm elongation at break determined in accordance with French - 51 42610 Standard Specification T 46,002: 396% tear strength in accordance with French Standard Specification T 46,007: 45 kg/cm. 2) Preparation of Ν,Ν'-bis-Cp-(vinyldimethylsilyl5 methoxy)-phenyl1-terephthalamide .35 g of l-amino-4-(vinyldimethylsilylmethoxy)benzene, 5.05 g of triethylamine and 50 cm of carbon tetrachloride are introduced into a three-neck 250 cm flask equipped with a mechanical stirrer, a reflux condenser, a dropping funnel and a thermometer, the whole being kept under an atmosphere of dry nitrogen.

The reaction mixture is cooled to -4C whilst stirring. A solution of 5.22 g of terephthaloyl chloride in 17 cm of acetone is introduced into the dropping funnel 15 and is then added uniformly over the course of 27 minutes to the contents of the flask. During the addition, the temperature is kept at between -4 and +2°C. The reaction mixture is left for a further 1 hour 30 minutes, whilst being stirred vigorously.

Thereafter, the reaction mixture is poured into 100 cm of water; the precipitate formed is filtered off, washed with 4 times 40 cm of a mixture of water and acetone, again filtered off and then dried at 110°C under reduced pressure (5 mm of mercury).

This gives 12.90 g of a product of melting point 315°C.

The IR and NMR spectra and the percentage composition show that the material is N,N'-[p(vinyldimethylsilylmethoxy)-phenyl]-terephthalamide. - 52 43S10 3) Preparation of l-amino-4~(vinyldimethylsilylmethoxy)-benzene 64.4 g of sodium p-nitrophenate are dissolved in 203 g of N-methylpyrrolidone and this solution is introduced into a flask. After heating to 90°C, 53.8 g of dimethylvinylchloromethylsilane are run in over the course of 13 minutes and 10 cm of N-methylpyrrolidone are added.

The reaction mixture is kept at about 100° for 20 hours, the sodium chloride is filtered off and the N-methylpyrrolidone is distilled under reduced pressure. The residual reaction mixture is dissolved in ether and the ether solution is washed with an aqueous sodium carbonate solution. After distilling the ether, 91 g of a yellow product'crystallising at 34° are obtained. The percentage analysis and infrared analysis show that the compound is p-(dimethyIvinylsilylmethoxy)-nitrobenzene.

A further quantity of this latter compound is prepared in accordance with the same method. Thereafter, the nitro derivative is reduced. 775 g of stannous chloride and 700 g of hydrochloric acid (d=1.19) are introduced into a flask and a solution of p-(vinyldimethylsilylmethoxy)-nitrobenzene containing 118.5 g of the nitro derivative and 150 em of ethanol is then run in over the course of 50 minutes at between 30 and 45°.

The reaction mixture is kept at 45° for 2 hours. After cooling, the following are carried out: filtration of the tin tetrachloride, washing with water, neutralisation with a concentrated sodium hydroxide solution and filtration of the precipitate formed. This precipitate is disolved in excess sodium hydroxide solution.

After extracting with ether, removing the ether hy evaporation, and rectification, a fraction of 79.8 g, of boiling point0 g : 115-117°, of p-(vinyldimethylsilylmethoxy)- aminobenzene is obtained: EXAMPLE 4 A thermoplastic elastomeric polymer 10 derived from N,N’-bis-[4-(vinyldimethylsilylmethoxy) phenylj-terephthalamide is prepared as follows: 3.17 g of N,N’-bis-[4-p-(vinyldimethylsilylmethoxy)-phenyl]-terephthalamide, 10.804 g of the α,ω-dihydrogenopolydimethylsiloxane used q in Example 1, 42 g of cyclohexane and 0.3 cmJ of a solution of H^PtClg in toluene, containing 3.3 x “6 3 gram atom of Pt/cnr are introduced into a reactor equipped as in Exanple 1 and the suspension obtained is heated to the boil. After 1 hour, an increase in the viscosity of the reaction mixture is observed; heating is continued for 7 hours 30 minutes; tlie reaction mixture is then in the form of a homogeneous solution. It is cooled to 20°C and the precipitation of a polymer swollen with solvent is observed. The cooled mass is heated to 80°C to cause the polymer to dissolve, and a film is then prepared as in Example 1, by - 54 4 2610 casting the solution on a plate heated to 80°C.

This gives a film of which the inherent viscosity 3 at 25°C, measured on a solution of 0.5 g in 100 cm of chloroform, is 36 cm /g.

Its percentage composition and its infra-red spectrum correspond to those of a polymer having the recurring unit; (ch3)2 W2 &3>2 CH2-Si-CH2-0-^>-NH-CO-^-CO-NH-^-0-CH2-Si-CH2-CH2-Si-(0-Si)-0-Si— The film obtained above has the following 10 mechanical properties (measured as in Example 1); breaking load; 48 kg/cm elongation at break; 275% EXAMPLE 5 l) Preparation of a thermoplastic elastomer derived from the N,N‘15 bis-Γρ-(vinyldimethylsilvlmethoxycarbonvl)-phenyl1terephthalamide of the formula: «JH3>2 CH =CH-Si-CH_-0-C 2 2 J NH-CO CO-NH-^^«jH3>2 C-0-CH--Si-CH=CH, | 2 0 -©-: 1.5 g of terephthalamide and 7.1 g of an α,ωdihydrogenopolydimethylsiloxane of number-average molecular weight 2,930, containing 0.068 atom of active hydrogen per 100 g of polymer, of viscosity 48 cst at 20°C, and containing about 30'dimethylsiloxane units, are introduced 4 2 610 into an apparatus equipped as in Example 1.

The contents of the flask are heated to 3 110° and 0.3 cm of a solution of hexachloroplatinic acid in toluene, containing 8 χ 10~θ gram atom of 3 platinum per cm is added, followed by an additional —5 quantity of chloroplatinic acid (1.9 x 10 gram atom of platinum). Heating is continued for 24 hours at 110°C and the solution is then cooled and poured into 2 1 of methanol, with vigorous stirring.

The precipitate is washed with 100 cm of methanol and then dried for 24 hours at 80 °C under reduced pressure (3 mm of mercury).

The inherent viscosity of the polymer measured at 25°C on a solution of 0.5 g in 100 cm of 3 chloroform is 30 cm /g. Its softening point is 120°C. 2) Preparation of N.N'-bis-fp-vinyldimethylsilylmethoxycarbonyl)-phenylΙ-terephthalamide. g of l-amino-4-(vinyldimethylsily lmethoxy3 carbonyl)-benzene, 8.6 g of triethylamine and 50 cm of acetone are,introduced into a three-neck glass flask of 3 250cm , equipped with a stirrer system, a reflux condenser, a dropping funnel and a thermometer.

A solution of 8.8 g of terephthaloyl chloride dissolved in 100 cm3 of acetone is introduced into the dropping funnel and is then introduced into the reaction mixture, kept at 35°C.

After adding 11 cm of the solution of terephthaloyl chloride, a white precipitate forms. 43610 The addition is continued and lasts for 1 hour minutes.

The reaction mixture is then brought to the boil and kept at its boiling point, namely 58°C, for 1 hour.

After cooling, the precipitate is filtered off on a glass frit and is then washed with 5 times 50 cm of water, suction-drained and then dried for 4 hours at 1OO°C under 25 mm pressure. 21.2 g of product are thus obtained.

IO The filtrate is precipitated by 500 cm3 of water, which makes it possible to obtain a further 3.57 g of product g of product originating from the 1st filtration . 3 are recrystallised from 250 cm of chlorobenzene, making it possible to obtain 8.9 g of pearlescent crystals identified as being N,3Sr'-bis-p-[(vinyldimethylsilylmethoxycarbonyl)phenylj-terephthalamide of melting point 26O°C.

EXAMPLE 6 1) Preparation of the thermoplastic elastomer 67.47 g of toluene, 15.06 g of an α,ω-dihydrogeno20 polydimethylsiloxane of number-average molecular weight 1,100 (n = about 13 in the formula I) and 7.42 g of 4,4’-N,N'-bis-[p-(vinyldimethylsilylmethoxy)-benzoyl}diaminobenzene of the formula . 3 are introduced into a 250 cm flask equipped with a stirring system, a thermometer, a reflux condenser and a heating device.

The suspension is heated under reflux whilst 3 stirring and 0.8 cm of a solution of chloroplatinic acid in toluene containing 3 χ 1Ο~θ gram atom of platinum per 3 cm is then added. The reaction mixture becomes viscous 5 and homogeneous. It is kept under reflux for 6 hours minutes.

Following the procedure of Example 1, a film is prepared from the reaction solution. A white elastomer is thus obtained, having a softening point of 190°C and an inherent viscosity of 40 cm^/g, measured at 20°C on a 3 solution containing 0.5 g in 100 cm of chloroform.

The percentage composition and the infra-red spectrum correspond to those of a polymer containing a plurality of recurring units of the formula: 2) Preparation of N,N'-bis-[p-(vinyldimethylsilyl)methoxy)-benzoyl] -4,4'-diamino benzene 21.6 g of p-phenylenediamine and 200 cm of N-methyl 3 pyrrolidone are introduced into a 500 cm three-neck flask 20 equipped with a mechanical stirrer, a thermometer, a condenser, a dropping funnel and a nitrogen inlet tube.

The solution is cooled to 5-10°C and a solution of 102 g of the chloride of p-(vinyldimethylsilylmethoxy)3 benzoic acid in 100 cm of N-methylpyrrolidone is added over the course of 1 hour.

The contents of the flask are then heated to 60°C and kept at this temperature for 1 hour. The hot reaction _ solution is added to 1 litre of iced water whilst stirring.

A beige precipitate is obtained, which is filtered off, washed with water and then dissolved in hot dioxane. This solution is filtered and the filtrate is then cooled to 20°C.

A white crystalline precipitate is obtained, which is filtered off and dried to constant weight. 83.5 g of a product of melting point 255°C, which is free from impurities and of which the infra-red spectrum agrees with that of Ν,N'-bis-[p-(vinyldimethylsilylmethoxy)-benzoyl]-4,4'-diamino10 benzene. .

The percentage analysis of the elements C, H and N gave the following results: C% = 65.13 = 6.75 15 = 5.25 EXAMPLE 7 1) Preparation of the thermoplastic elastomer with recurring unit : W2 I -Si-CHj-O-^-C-NH-Q-O-C-Q-NH-C-^- O-CH,-Si~CH,-CH--Si-( O—Si-HO-Si/28 40.11 g of dioxane, 10.21 g of an κ,ω-dihydrogenopolydimethylsiloxane of number-average molecular weight 2,150, used in Example 6, and 3.15 g of N--[p-(vinyldimethylsilylmethoxy)-benzoyl]-p-aminophenyl N'-[p-(vinyldimethylsilylmethoxy)-benzoyl]-p-aminobenzoate are introduced into 25 the apparatus described in Example 6.

The contents of the flask are heated to the reflux 3 temperature whilst stirring and 3 cm of the catalyst solution used in Example 6 are then added.

The mixture is kept under these conditions for 5 hours 30 minutes. A film is prepared from the reaction solution. This gives a white elastomer having a softening point of 160°C, and having an inherent viscosity of 25 cm3/g, measured as in Example 6.

The percentage composition and the infra-red spectrum correspond to those of the polymer having the above recurring unit. 2) Preparation of p-aminophenyl N,N'-bis-Γρ(vinyldimethylsilyImethoxy)benzoyl]-p-aminobenzoate g (0.1 mol) of p-aminophenyl p-aminobenzoate and 100 cm of N-methylpyrrolidone are introduced into the apparatus described in Example 6.

A suspension is obtained, which is kept at between 5 and 10°C whilst a solution of 51 g (0.2 mol) of the chloride of p-(vinyldimethylsilyImethoxy)-benzoic acid in cm of N-methylpyrrolidone is added thereto over the course of 1 hour. The reaction solution is kept at 20°C for 2 hours after the end of the addition, and is then added to 800 cm of iced water whilst stirring. A precipitate is thus formed, which is filtered off and then washed with water on the filter. The precipitate is dissolved in hot dioxane, the solution is filtered and the filtrate is cooled to 20°C.

This gives 56 g of a crystalline white product free from impurities, which has a melting point of 213°C and of which the infra-red spectrum agrees with that of p-aminophenyl Ν,N1-bi s—[p-(vinyldimethyls ilylmethoxy)benzoyl]-p-aminobenzoate.

The percentage analysis of the elements C, H and N gave the following results: c% 66.59 = 6.18 - 4.04 EXAMPLES 8 to 11 Following the procedure of Example 1, a series of thermoplastic elastomers is prepared by polyaddition of the 4,4'-N,N,-bis-[p-(vinyldimethyl3 silylmethoxy)-benzoyl]-dLaminodiphenylmethane, used in Example 1, with a series of α,ω-dihydrogenopolydimethylsiloxanes of varying number-average molecular weight; the elastomers obtained contain a plurality of recurring units analogous to that indicated in Example 1.

Films are prepared from the polymers thus obtained, in accordance with the process described in Example 1, and the mechanical properties and inherent viscosity are determined on these films.

The results have been listed in the table which follows: 4SG10 EXAMPLES «,ω-DLhydroyeno- {xslydimethyleiloxane Elastomers Μη ---! η ^inh in cm3/g breaking load in kg/cm2 Elongation at break in % δ 1,4-30 17.5 64 115 600 9 1,820 22.7 66 88 690 10 2,420 31 68 56 730 11 2,800 36 77 46 720

Claims (2)

1. A thermoplastic polysiloxane elastomer which possesses plurality of recurring units of the general formula: ·- ι which each of R and R* , which may be identical or different, o o spresents a linear or branched alkylene group or a cycloalkylene roup optionally substituted by 1 td 4 atoms of chlorine and/or Luorine, said group containing from 2 to 10 carbon atoms; each of λ and fi', which may be identical or different, ^presents a valency bond or one of the following groups i« 3 ? 2 Si(R 3 , 2 -; -Si-0-; (XI) (HI) (R 3 } 2 ^3^2/=1 -Si-(CH 2 ) n -Si-4>(IV) (V) herein each of the radicals R 3 , which may be identical οιiff erent, represents a methyl radical or a phenyl radical, nd n^ is 1, 2 or 3; each of R^, R'^ and to Q g , which may be identical r different, represents a linear or branched alkyl radical ptionally substituted by one or more halogen atoms or cyano iroups, an aryl radical or alkylaryl radical optionally lUbstituted by one or more halogen atoms; each of R 2 and R‘ 2 , which may be identical or different, represents a linear or branched alkylene or alkylidene radical ontaining up to 4 carbon atoms; each of X and X', which may be identical or different, represent a functional group of the formula : 1 0-, -S' -C-0-, -C-S-, -C-Ο-, -C-S- or -N-, κ ii if li ι 0-0 S S said group being linked by a heteroatom to the radicals and R'j. and wherein R^ is a hydrogen atom or an alkyl radical containing from 1 to 6 carbon atoms; each of 1 and f', which may be identical or different, 5 represents an organic radical containing crom 1 to 30 carbon atoms, which is: (1) a divalent radical which is a linear or branched alkylene radical, an alkylidene radical or a cycloalkylene radical, optionally substituted by one or more chlorine 10 atoms, a monocyclic or polycyclic arylene radical optionally substituted by one or more methyl radicals and/or more than one chlorine atom, a saturated or unsaturated or aromatic monocyclic or polycyclic heterocyclic radical containing at least one Ο, N or S atom optionally substituted by .5 one or more methyl radicals or a chain of alkylene and/or alkylidene and/or cycloalkylene and/or arylene and/or divalent heterocyclic radicals linked to one another by a valency bond and/or by at least one of the groups: -0-, -S-, -NR,-. -COO-, -CONR.-, -SO.-, -N=N-, -N=N- . — C U 4 2 | It ' o o T 0 and -Ρ- (XI) I R 5 wherein Rg represents an alkyl radical having from 1 to 4 carbon atoms a cyclohexyl radical or a phenyl radical: 2. (2) a trivalent radical which is a benzenetriyl radical, a naphthalenetriyl radical, a pyridinetriyl radical or a radical 5 of the formula: - 64 42610 (XII) in which E represents a valency bond or an alkylene or alkylidene group having from 1 to 4 carbon atoms, an oxygen atom, a sulphur atom or one of the groups: -C00-, -SO,-, -C- and -C-NH-, 2 il II o o in which one of the free valencies is attached to X or X', respectively, end the remaining two valencies are attached to the carbonyl group in formula (XX) below; ItT is an organic radical of the formula: -0-^-0-, -HR^-C-NR^- or -NR^-CO-OO 0 -T-R-T'(VII) (VIII) in which: R represents a divalent organic radical or, additionally, • , a valency bond when -T-R M -T'- represents 65 42610 -O-C-C-O-, -S-C-C-S- or -NR?,-C-C-NR, II II II II 4 II II 4 oo oo oo R' represents a trivalent organic radical; R represents a tetravalent organic radical; each of τ and Τ' , which may be identical or different, represents a functional group of the formula: -C-0II -οδ-C-Ν-, -NH-C0-N-, -NH-C-0-, -NH-C-S-, II I I 1 II 0 R 4 R 4 0 0 (X) either end of which may be attached to a divalent group r or r',or .0 ,- CO — --NC/ Coin which the carbonyl groups are attached to a trivalent group £ or Γ'; and n is a number from 0 to 2,000.

2. An elastomer according to claim 1, in which the symbols R„ and R‘ , R, and R',, R~ and R' , X and X’, Γ and Γ* and A and ο ο 1 12 2 are respectively identical to one another· 3. An elastomer according to claim 1 or 2, in which R q and R o * represent a linear alkylene radicals having from 2 to 6 carbon atoms. k. An elastomer according to claim 1 or 2, in which R Q and R ’ represent ethylene, 1,3-propylene, 1,4-butylene, hexamethylene, monochloroethylene or 1,2-difluoroethylene groups. 5. An elastomer according to any one of claims 1 to 4, in which R^ and R^' and to represent linear or branched alkyl groups having up to 10 carbon atoms, optionally substituted by 1 to 4 atoms of chlorine and/or fluorine or by a cyano group, phenyl groups optionally substituted by 1 to 4 atoms of chlorine and/or fluorine, or alkylaryl radicals containing from 1 to 4 carbon atoms in the alkyl radical and optionally substituted by 1 to 4 atoms of chlorine and/or fluorine. 6. An elastomer according to claim 5, in which Rj, Rj, ' and to Q g represent alkyl radicals having at most 6 carbon atoms, or phenyl, tolyl or xylyl radicals optionally substituted by 1 to 4 atoms of chlorine and/or of fluorine and/or a cyano group. 7. An elastomer according to claim 6, in which R l' R l‘ an< ^ ®1 to % re P resent a methyl, ethyl, propyl, isopropyl, n-pentyl, chloromethyl, dichloromethyl, difluoromethyl, 3,3,3-trifluoropropyl, β-cyanoethylphenyl, m-chlorophenyl, 3,5-dichlorophenyl, o-tolyl, p-tolyl, 2,3-dimethylphenyl or 3,4-dimethylphenyl radical. 8. An elastomer according to any one of claims 1 to 7, in which λ and λ' represent a valency bond. 9. An elastomer according to any one of claims 1 to 8, in which Γ and f represent: a) an alkylene or alkylidene radical having from 1 to 12 carbon atoms or a cycloalkylene radical having from 5 to 8 carbon atoms; b) a phenylene, tolylene, xylylene, naphthalene or anthracenylene radical; c) a saturated or unsaturated or aromatic heterocyclic radical containing at least one 0, N .or S atom and 4 to 6 atoms in the ring; d) a divalent radical consisting of a chain of 2 to 4 radicals as defined under a) and/or b) and/or c) linked to one another by a valency bond and/or by at least one of the groups: - 67 I 4261 Ο -Ο-, -S-, -ΝΗ-, -COO-, -CONH-, -SO-Ν=Ν-, -Ν=Ν-, I- and ίο Rg and/or by an alkylene and/or alkylidene group having from 1 to 4 carbon atoms. 5 10. An elastomer according to claim 9, in which ΐ and Γ' represent an alkylene or alkylidene radical having from 1 to 6 carbon atoms, a cyclohexylene radical, a m- or p-phenylene radical, a 1,2-dimethyl-3,666 phenylene radical, a 2-methyl-1,4-phenylene radical, a 5-methyl-l,3-phenylene radical or a radical formed by two phenylene groups linked to one another by a valency bond, an alkylene or alkylidene group having from 1 to 4 carbon atoms, an oxygen atom or one of the groups -NH-, -SOj-, -C-NH- and -C-. ° II 11. An elastomer according to any one of claims 1 to 9 in which T and Τ' represent a 1,2,4benzenetriyl radical or a radical of the formula: 43610 12. Λη elastomer according to any one of claims 1 to 11, in whichT represents a divalent group of formula (VII) in which R represents (1) a linear or branched alkylene radical, an alkylidene radical, a cycloalkylene radical or a monocyclic or polycyclic arylene radical optionally substituted by one or more alkyl radicals having from 1 to 4 carbon atoms and/or by one or two cyano, amide, nitro, ester, alkoxy, hydroxyl, amine or hydroxycarbonyl groups, and/or by one or more halogen atoms; (2) a saturated or unsaturated or aromatic monocyclic or polycyclic divalent heterocyclic radical which contains at least one 0, N or S atom and is optionally substituted by one or more methyl radicals; or (3) a chain of alkylene and/or alkylidene and/or cycloalkylene and/or arylene and/or divalent heterocyclic radicals linked to one another by a valency bond and/or an oxygen atom and/or a sulphur atom and/or at least one of the groups: -N - COO -· -C0NR /+ -; -S0 2 -N = N -; 0 (R 3 ) 2 (R 3 ) ? N = N - C ~; -P-; -Si-; - Si - 0 -; II o ^5 -Si - (CH 2 ) n -; - (CH,- Si - 0 - k - (CH,)~ 2'n '2'n., (CH 2 ) ni - k (pp2 (CII,) - Si - (CH,) and n l Z n l - 70 42610 < CIi 2>n, -ΐ’ί 13. An elastomer according to claim 12, in which 'ψ' represents a group of the formula (VII) in which R represents: a) an alkylene or alkylidene radical having at most 12 carbon atoms or a cycloalkylene radical having from 5 to 8 carbon atoms; b) a phenylene, tolylene, xylylene, naphthylene or anthracenylene radical optionally substituted by one or more chlorine atoms; c) a saturated or unsaturated or aromatic heterocyclic radical containing one or two heteroatoms which may be nitrogen and/or sulphur and/or oxygen and containing 4 to 6 atoms in the ring, and optionally substituted by one or two methyl groups; or d) a divalent radical consisting of a chain of 2 to 4 radicals as defined under a) and/or b) and/or c) and linked to one another by a valency bond and/or an oxygen atom and/or a sulphur atom and/or by at least one of the groups: -NH-CO-, -C00-, -SO 2 -, -N=N-, -CO-, and -NH and/or by an alkylene or alkylidene radical containing from 1 to 4 carbon atoms. l4. An elastomer according to claim 13, in which ‘ψ’ represents a group of the formula (VII) wherein R is an alkylene group having from 1 to 8 carbon - 71 42610 atoms, a cyclohexylene radical, a p-phenylene radical, a radical containing from 2 to 4 phenyl groups linked by a valency bond and/or by an oxygen atom and/or by the groups: O o 4 || -NH-CO-, -C- , -SO.- , -NH- , -Ρ- , and -C-OII 2 I and/or by a methylene and/or isopropylidene group, or a radical containing two alkylene groups having from 1 to 4 carbon atoms, linked to a benzene ring by a valency bond and/or by an oxygen atom and/or by the groups -CII -S0 2 - , -NHO -C-0- , -NH-CO- and -PII I 0 R 5 15. An elastomer according to any one of claims 1 to 11 whichY represents a group of formula (VIII) in which R' represents: a saturated aliphatic hydrocarbon radical having from 2 to 20 carbon atoms, a saturated cycloaliphatic hydrocarbon radical containing 5 or 6 carbon atoms, a saturated or unsaturated or aromatic heterocyclic radical containing at least one Ο, N or S atom and from 4 to 6 atoms in the ring, or a monocyclic or polycyclic aromatic radical in which the rings are fused or linked to one another by a valency bond and/or by an oxygen atom and/or by a sulphur atom and/or by an alkylene or alkylidene radical having from 1 to 4 carbon atoms and/or by at least one radical of the formula: -NH-, -C00-, -C0-, -CO-Ν-, -SO.-, I 2 R -N=N-, -N=N£ - 72 42610 -CO-Ν-Δ—, -COO-Δ-OCO- and I O Τ' -PI Rr, (XIII) in which Δ is an alkylene radical having at most 12 carbon atoms or a eycloaXkylene radical having 5 or 6 carbon atoms, the aromatic rings optionally being substituted by one or more chlorine atoms and/or methyl groups. 16. An elastomer according to Claim 15, in which R“* represents a cyclohexanetriyl radical, a benzenetriyl radical or a radical corresponding to ) the formula: - 73 42610 17. An elastomer according to claim 16, in which R 1 represents a 1,2,4-benzenetriyl radical. 18. An elastomer according to any one of claims 1 to 11, in which ^represents a group of formula (IX) in which R u represents: a saturated aliphatic hydrocarbon radical having from 2 to 20 carbon atoms, a saturated cycloaliphatic hydrocarbon radical containing 5 or 6 carbon atoms, a saturated or unsaturated or aromatic heterocyclic radical containing at least one Ο, N or S atom and from 4 to 6 atoms in the ring, or an aromatic monocyclic or polycyclic radical in which the rings are fused or linked to one another by a valency bond and/or by an oxygen atom and/or by a sulphur atom and/or by an alkylene or alkylidene radical having from 1 to 4 carbon atoms and/or by at least one radical of the formula: -NH-, -C0O-, -CO-, -CON-, -SOg·, -N=N-, -N=N-, ί Z k -CO-N-4-, -COO-A-O-CO- and I R, 4-Pthe aromatic rings optionally being substituted by one or more chlorine atoms and/or methyl groups. 19. An elastomer according to claim 18, in which R““ represents a 1,2,4,5-cyclohexanetetrayl radical, a 1,2,4,5-benzenetetrayl radical or a radical of the formula: - 7/ t 42610 20. An elastomer according to any one of claims 1 to 19, in which n is a number of from 10 to 200. 21. An elastomer according to claim 20 in which n is a number from 10 to 80. claims of the -COO-, 22. An elastomer according to any one of 1 to 21, in which f and f* represent a group formula: -CONH-, -NH-COO-, -NH-CO-NH- or -N co'C023. An elastomer according to claim 1 which comprises a plurality of units of the formula: 24- An elastomer according to claim 1, which comprises a plurality of units of the formula: - 75 42610 25. An elastomer according to claim 1, which comprises a plurality of recurring units of the formula: 26. An elastomer according to claim 1, which comprises a plurality of recurring units of the formula: 10 27. An elastomer according to claim 1, which comprises a plurality of recurring units of the formula - 76 42610 28. An elastomer according to claim 1, which comprises a plurality of recurring units of the formula: 29. Process for the preparation of a thermoplastic elastomer as claimed in claim 1 which comprises reacting at least one diethylenic silicon compound of the general formula: ,1'2 V ,1 ‘2 R-X-Si-R 2 -X-f-Y -f’-X’-R ‘-Si-A'-R* (XXV) in which λ, λ 1 , Rp RjJ , R 2 > R 2 ‘, X, X', f, f-andV are as defined in claim 1 and each of R and R*, which may be identical or different, represents a monovalent organic radical containing an ethylenic double bond and at most 10 carbon atoms, with at least one α,ω-dihydrogenopolysiloxane of the general formula: Pl Οι 2 (O-SiQ,. ?5 O-SiI Q 6 U-H (XV) b b wherein to and n are as defined in claim 1, optionally in the presence of a catalyst for the hydrosilylation of ethylenic double bonds. 30. Process according to claim 29, in which R and R 1 are linear or branched alkenyl radicals 77 43610 optionally substituted by one or more halogen atoms, or cycloalkenyl radicals optionally substituted by one or more halogen atoms. 3Ϊ. Process according to claim 30, in 5 which R and R* are linear alkeiiyl radicals having from 2 to 6 carbon atoms. 32. Process according to claim 31, in which R and R' are linear alkenyl radicals with a terminal ethylenic double bond. 10 33. Process according to claim 32, in which R and R' are identical.___ - 78 42610 34- Process according to claim 33, in which R and R* are vinyl, allyl, prop-2-en-l-yl, but-3-en-l-yl, pent-4-en-l-yl or hex-5-en-l-yl groups. 35. Process according to any one of claims 29 to 34 which is carried out at a temperature from 0 fco 300°C and at a pressure below, above or equal to atmospheric pressure, 36. Process according to any ono of claims 29 to 35 which is carried out in the presence of an initiator of free radicals, as the hydrosilylation catalyst. 37. Process according to any one of claims 29 to 36, which is carried out in the presence of at least one metal of group VIII or a derivative thoeof, as catalyst, 38. Process according to claim 37, in which-the metal is Pt, Ru, Hh, Pd or Ir. 39. Process according to claim 38, in which the hydrosilylation catalyst used is elementary platinum deposited on a support, hexachloroplatinic acid or an alkali metal salt thereof or a reaction product thereof with an alcohol, ether, aldehyde or cyclopropane or a complex of a platinum halide with a phosphine. 40. Process according to any one of claims 29 to 39 which is carried out in solution or in suspension in an organic solvent which is inert towards the reactants and which is a saturated aliphatic or cycloaliphatic hydrocarbon, an aromatic hydrocarbon optionally substituted by one or more halogen atoms, or an alcohol, ether or ester. ‘ ini 41. Process according to any one of claims 29 to 4θι in which the relative amounts of the reactants (XIV) and (XV), expressed in terns of the ratio of the number of alkenyl groups to the number of active 5 hydrogen atoms, are such that this ratio is from 2 to 0,5. 42. Process according to claim 41, in which the said ratio is from 1.2 to O.S. 43. Process according to any one of claims 29 10 to 42, which is carried out in the presence of at least one chain stopper which is a silicon compound containing a single hydrogen atom linked to silicon, a silicon compound containing a single alkenyl group or a monoothylenic organic compound. —44. Process according to any one of claims 37 to 43, i n which the amount of metallic catalyst, expressed in the number of gram atoms of metal per alkenyl group present in the compound (XIV) is from 10“ 6 to 10\ 45. Process according to claim 29 for the 20 preparation of an elastomer as claimed in claim 22 which conprises reacting 4,4'-Η,N*-bis[p-(vinyldimethyls ily 1methoxy)~ben2oyl]-diaminodiphenylmQthane with an α,ω-dihydrogenopolydimethylsilaxanQ of number-average molecular weight 2,150 and of viscosity 26,5 cst at 25 e c, 25 in the presence of chloroplatinic acid in toluene or twtyl acetate, 46. Process according to claim 29 for the % preparation of a thermoplastic 3ilaxane elastomer as claimed in claim 23 which comprises reacting N,N‘-bis^[p~ (viny Idiroe thy Isily Ime thoxy) -phenyl]-terephthalamide with an a,w-dihydrogenopolydimethyl3iloxane of numberaverage molecular weight 1,114 and of viscosity 9.3 cst at 25°C in the presence of chloroplatinic acid in toluene. 47. Process according to claim .29 for the preparation of a thermoplastic siloxane elastomer as claimed in claim 24 which comprises reacting NjN’-bis[p-(vinyldime thylsilylmathoxy)-phenyl]-terephthalamide with an a,w-dihydrogenopolydimethylsiloxane of numberaverage molecular weight 2,150 and of viscosity 26.5 cst at 25°C in the presence of chloroplatinic acid and in cyclohexane. 48. Process according to claim 29 for fche preparation of a thermoplastic siloxane elastomer as claimed in claim 25 which coinprises reacting Ν,Ν'-bis[p—(vinyldimethylsilylmethoxycarbonyl)-phenyl]-terephthalamide with an α,ω-dihydrogenopolydimethylsiloxane of number-average molecular weight 2,930 and viscosity 48 cst at 20®C. .49- Process according to claim 29 substantially as hereinbefore described. 50. Process according to claim 29 substantially as described in any one of the Examples. 51. A thermoplastic siloxane elastomer as defined in claim 1 whenever prepared by a process as claimed in any one of claims 29 to 50.