JPH0474382B2 - - Google Patents

Description

[Detailed description of the invention]

BACKGROUND OF THE INVENTION The present invention relates to thermosetting silicone-polyimides obtained using platinum catalysts and silicon hydride terminated polyimides. Prior to the present invention, compositions of room temperature vulcanizable polydiorganopolysiloxanes, such as silanol-terminated polydimethylsiloxanes, were available in one-package or two-package systems depending on the nature of the moisture-sensitive crosslinker used. The typical one-package system is
As shown in U.S. Pat. No. 3,133,891 to Ceyzeriat, metholtriacetoxysilane and silanol-terminated polydimethylsiloxane are used. In two-package systems, such as that shown in Nitzsche et al., U.S. Pat. No. 3,065,194, a silanol-terminated polydimethylsiloxane is used as a curing catalyst and
For example, it is necessary to combine it with a combination of ethyl orthosilicate and dibutyltin dilaurate. In the two-package system, the curing catalyst must be mixed with the silanol-terminated polydimethylsiloxane prior to use. In the one-package and two-package room temperature vulcanizable compositions described above, reinforcing fillers, such as silica fillers, are typically added to the silicone polymer if high tensile strength is desired in the resulting cured silicone.
Amounts of 5 to 300 parts per part should be used. Another method that can be employed to increase the toughness of cured silicone polymers is to introduce sylarylene siloxy units into the polymer chain, resulting in substantial chemical bonding of diorganosiloxy units and sylarylene siloxy units. Produces a copolymer. Although these methods can significantly increase the modulus (psi) of silicone polymers, these methods are not economical and the final product has a desirable It cannot provide toughness. In my US patent application Ser. No. 442,682, silicone-polyimide copolymers are described as having silanol or silicon hydride end groups based on the use of norbornene-terminated polyimides. A hydrosilanization reaction is used to introduce silicon-hydrogen into the terminal positions of the norbornene-terminated polyimide. The resulting hydrosilyl-terminated polyimide is reacted with a silanol-terminated polydiorganosiloxane in the presence of a catalyst to form a silanol-terminated polydiorganosiloxane-polyimide copolymer.
Room temperature or low temperature condensation vulcanizable compositions based on the use of such silanol-terminated copolymers result in cured silicone-polyimide copolymers exhibiting excellent toughness. Now, the present inventor newly developed polyvinylarylsilane or vinyl-containing polydiorganosiloxane and the following formula: It has been found that mixtures of silicon hydride-terminated polyimides having the following properties can be readily vulcanized with platinum catalysts at temperatures from about 25°C to about 250°C. In the above formula, R~ ^R8 , Y,
Q, r and n are as defined below. Alternatively, the following formula: The vinyl terminated silicone-polyimide block polymer can be vulcanized with a silicon hydride compound as defined below in the presence of an effective amount of a platinum catalyst. R ⁷ in the above formula is as defined below,
R ⁹ is CH ₂ CH ₂ , m is an integer of 1 to 100, x is an integer of 1 to 10 ⁴ , and G is the silicon hydride-terminated polyimide of formula (1): is a divalent group formed by reacting with a vinyl-terminated polydiorganosiloxane. The resulting silicone-polyimide elastomeric copolymers have high tensile strength (psi) compared to conventional room temperature vulcanized or heat cured organopolysiloxane elastomers. Summary of the Invention Thermosetting silicone provided by the present invention
The polyimide block copolymer comprises, by weight, (A) 100 parts of a silicon hydride terminated polyimide of formula (1); (B) 1 to 500 parts of substantially the formula: The diorganosiloxy unit of and the following formula chemically bonded thereto: (C) an effective amount of a platinum catalyst; and (C) an effective amount of a platinum catalyst. R ⁷ in the above formula
is defined below and R ¹⁰ is selected from C ₂ H ₃ and R ⁷ . The group contained in R in formula (1) is, for example, (a) an aromatic hydrocarbon group having 6 to 20 carbon atoms and its halogenated derivative, (b) an alkylene group having 2 to 20 carbon atoms. groups and cycloalkylene groups and
C _(2-8) alkylene-terminated polydiorganosiloxane,
and (C) the following formula: is a divalent C _(2-20) organic group selected from the group consisting of divalent groups contained in

【formula】

[Formula] is a group selected from the group consisting of -S- and -C _x ′H _2x ′-, where x′ is 1 to 5
is an integer. The group contained in Q in formula (1) is

[expression] and

【formula】 is a tetravalent group selected from -O-, -S-,

【formula】

【formula】

is a group selected from [Formula] and -OR ¹¹ O-, and R ¹¹ is

【formula】 【formula】

【formula】

【formula】

【formula】

【formula】

[Formula] and general formula: is a divalent group selected from divalent organic groups of X
is −C _y H _2y −,

【formula】

[Formula] is a group selected from the group consisting of divalent groups of -O- and -S-,
y is an integer from 1 to 5, R ¹ to R ⁶ are selected from hydrogen and C _(1-8) alkyl groups, and R ⁷ is the same or different monovalent C _(1-13) hydrocarbon group and monovalent substituted C _(1-13) is a hydrocarbon group, Y is a divalent group selected from -O- and -C(R ¹ ) ₂ -, r is equal to 0 to 2000, and n is equal to 0 to 200. integer, R ⁸ is hydrogen and
selected from R ⁷ and p equals 0 or 1. The above silicon hydride terminated polyimide has the following formula: of norbornene-terminated polyimide and the following formula: and a silicon hydride compound in the presence of an inert organic solvent and an effective amount of a platinum catalyst to evaporate the inert organic solvent. R to R ⁸ , Y, Q, n and r in the above formula are as defined above. Groups included in R ¹ to ^{R 6} in formulas (1) and (4) are, for example, hydrogen, methyl, ethyl, propyl, butyl, and the like. Groups included in R ⁷ include, for example, aryl groups and aryl halides, specifically phenyl, chlorophenyl, tolyl, xylyl, biphenyl, ofthyl, etc.; alkenyl groups, specifically vinyl, allyl, cyclohexenyl, etc.; C _{( 1-8)}
Alkyl groups and halogenated alkyl groups, specifically methyl, ethyl, propyl, butyl, octyl and the like. The norbornene-terminated polyimide of formula (4) can be formed by reacting an organic diamine, norbornene anhydride, or optionally norbornene dicarboxylic acid monoalkyl ester, and an organic dianhydride according to the following formula. Here, Q, R, R ¹ to R ⁶ and Y are as defined above. In carrying out the present invention, examples of organic dianhydrides that can be used together with norbornene anhydride or norbornene dicarboxylic acid monoalkyl ester to produce the norbornene-terminated polyimide of formula (4) include benzophenone dianhydride, Pyromellitic dianhydride, 2,2-bis[4-(3,4-dicarboxyphenoxy)phenyl]propane dianhydride, 2,2-bis[4-(2,3-dicarboxyphenoxy)phenyl] ) phenyl]propane dianhydride, 4-
(2,3-dicarboxyphenoxy)-4'-(3,
4-dicarboxyphenoxy)diphenyl-2,
2-propane dianhydride, and the following formula: bisnorbornane siloxane dianhydrides and mixtures thereof. Examples of organic diamines that can be used to form the polyimide block of the silicon hydride-terminated polydiorganosiloxane-polyimide copolymer are: o-phenylene diamine, m-phenylene diamine, p-phenylene diamine, 4 , 4'-diaminodiphenylpropane, 4,4'-diaminodiphenylmethane (usually 4,
4'-methylene dianiline), 4,4'-diaminodiphenyl sulfide (commonly known as 4,4'-thiodianiline), 4,4'-diaminodiphenyl ether (commonly known as 4,4'-oxydianiline), 1,5-diaminonaphthalene, 3,3'-dimethylbenzidine, 3,3'-dimethoxybenzicine, 2,4-bis(β-amino-t-butyl)toluene, 1,3-diamino-4-isopropylbenzene , 1,2-bis(3-aminopropoxy)ethane, benzidine, m-xylylenediamine, p-xylylenediamine, 2,4-diaminotoluene, 2,6-diaminotoluene, bis(4-aminocyclohexyl)methane , 3-methylheptamethylenediamine, 4,4-dimethylheptamethylenediamine, 2,11-dodecanediamine, 2,2-dimethylpropylenediamine, octamethylenediamine, 3-methoxyhexamethylenediamine, 2,5-dimethylhexamethylene Diamine, 2,5-dimethylheptamethylenediamine, 3-methylheptamethylenediamine, 5-methylnonamethylenediamine, 1,4-cyclohexanediamine, 1,12-octadecanediamine, bis(3-aminopropyl)sulfide, N- Methyl-bis(3-aminopropyl)amine, hexamethylenediamine, heptamethylenediamine, nonamethylenediamine, decamethylenediamine, bis(3-aminopropyl)tetramethyldisiloxane, bis(4-aminobutyl)tetramethyldisiloxane and mixtures of these diamines. In addition to the silicon hydride compound of formula (5), the thermosetting composition of the present invention includes
Silicon hydride-containing siloxanes such as those shown in Faltynek US Pat. No. 4,329,274 may also be used.
For example, a silicon hydride resin consisting of substantially chemically bonded diorganohydride siloxy units and SiO ₂ units, in which the silicon-bonded organo group is the same as R ⁷ , a silicon hydride resin consisting of substantially chemically bonded diorganohydride siloxy units and SiO 2 units, and Linear hydride polysiloxanes consisting of diorganosiloxy units as defined, and linear hydride polysiloxane couplers consisting of substantially chemically associated diorganosiloxy units and terminal diorganohydride siloxy units, and A mixture of silicon hydride-containing siloxanes can be used. Examples of polyvinyldiorganosiloxanes used in the thermosetting organopolysiloxane compositions of the present invention include the following formula: There are some things included. where R ⁷ and R ¹⁰ are as defined above and t is a positive integer having a value sufficient to provide the vinyl siloxane viscosity as defined above. Preferably, the polyvinyldiorganosiloxane contains terminal units of _the formula: _C2H3 ( _CH3 ) _2SiO0.5 in an amount ranging from _about 0.05 to about 3.5 mole%, preferably from about 0.14 to about 2 mole%. do. Polyvinyldiorganopolysiloxanes, both linear and cyclic polysiloxanes, can be prepared by equilibration reaction of a suitable cyclotetrasiloxane with a suitable vinyl-terminated low molecular weight polysiloxane chain terminator. The equilibration reaction catalyst used is a mild acid catalyst such as toluenesulfonic acid or an acid-treated clay such as Filtrol.
(a sulfuric acid activated clay manufactured and sold by Filtrol Corporation, Los Angeles, Calif.). Once the equilibration reaction has proceeded to the point where approximately 85% of the cyclopolysiloxane has been converted to the linear polymer, the acid catalyst can be neutralized with a base or, in the case of acid-activated clays, simply separated and converted to the linear polymer. leave behind. Excess cyclics are preferably stripped off so that the linear polymer is relatively pure with low volatile content. It is also possible to use alkali metal hydroxides as catalysts, such as potassium hydroxide or sodium hydroxide. Platinum catalysts that can be used to carry out the invention include:
See, for example, Karstedt U.S. Pat. No. 3,775,442, Ashby, U.S. Pat.
3220972, platinum complexes of unsaturated siloxanes. An effective amount of platinum catalyst is from about 10 ^-4 to 0.1% by weight platinum, based on the weight of the curable hydrosilanization reaction mixture. Examples of silicon hydrides that can be used in the practice of this invention include: There is a hydride coupler with here,
R ⁷ and R ⁸ are as defined above, a and b are integers having a value of 0 to 200, and the sum of a+b has a value of 0 to 400. Various fillers and pigments can be kneaded into the room temperature vulcanizable composition of the present invention. For example, titanium dioxide, zirconium silicate, silica aerogel, iron oxide, diatomaceous earth, fumed silica, carbon black, precipitated silica, glass fiber, polyvinyl chloride, quartz powder, calcium carbonate, etc. can be used. It is clear that the amount of filler used can vary within wide limits depending on the intended use. For example, in certain sealant applications, the curable compositions of the present invention can be used without fillers. For other uses, such as when using the cured composition to form a binder, large amounts of filler may be used, such as 700 parts or more per 100 parts of polydiorganosiloxane-polyimide copolymer on a weight basis. I can do it. In such applications, the bulk of the filler can be bulking materials such as quartz powder, polyvinyl chloride or mixtures thereof, preferably having an average particle size in the range of about 1 to 10 microns. The synthesis of norbornene-terminated polyimide of formula (4) is as follows:
This can be carried out in a conventional manner using equimolar amounts of the organic diamine and dianhydride together with an effective amount of the chain terminating norbornene anhydride or norbornene dicarboxylic acid monoalkyl ester; A sufficient amount can be used to form a polyimide. During the polymerization of norbornene-terminated polyimide, organic solvents such as o-
Dichlorobenzene can be used and temperature range from 140℃ to 200℃
Temperatures within the range of can be adopted. The reaction is preferably carried out under an inert atmosphere, such as nitrogen, to minimize undesirable side reactions. Reaction times can vary from less than 30 minutes to 3 hours depending on the nature of the reactants, the desired molecular weight of the polyimide, etc. The silicon hydride-terminated polyimide of formula (1) can be prepared by reacting the norbornene-terminated polyimide of formula (4) with a suitable silicon hydride compound of formula (5), such as dihydrogen silane or dihydrogen disiloxane, in an effective amount. It can be synthesized by carrying out the synthesis in the presence of a platinum catalyst. An effective amount of platinum catalyst is from about 10 ^-6 parts to 10 ^-3 parts per part of the hydrosilanization reaction mixture consisting of norbornene-terminated polyimide, silicon hydride compound, and inert organic solvent.
This is the platinum of the department. The inert organic solvent can be used in an amount sufficient to produce a mixture containing 10 to 50 weight percent solids. Suitable inert organic solvents that can be used are, for example, toluene, chlorobenzene and o-
It is dichlorobenzene. Preferably, the hydrosilanization reaction is carried out under substantially anhydrous conditions at a temperature in the range of 0°C to 200°C. The following examples are presented by way of illustration and not by way of limitation, to enable those skilled in the art to better practice the invention. All parts are parts by weight. Example 1 19.62 g (0.1 mol) of norbornene dicarboxylic acid monomethyl ester and 9.9 g (5 x 10 ^-2 mol)
A mixture of 4,4'-methylene dianiline was dissolved in 50 ml of dry methanol. The solution was refluxed under nitrogen for 2 hours. The solvent was then evaporated and the residue heated internally to 150° C. for 2 hours under a nitrogen atmosphere. Dissolve the residue in 50ml of dehydrated dichloromethane and add 300ml
of methanol. A white precipitate was obtained,
When this was washed with methanol and dried, the yield was
It was 25.7g (98%). Based on the manufacturing method, this product has the following formula: This was confirmed by spectroscopic data. 0.49 g (10 ⁻³ mol) of the above diimide and 3 g
Five drops of 5% by weight platinum catalyst were added to a solution of silicon hydride-terminated polydimethylsiloxane (molecular weight approximately 1500) dissolved in 40 ml of dehydrated chlorobenzene. The resulting solution contained approximately 0.03% by weight platinum, based on the total weight of the solution, and the solution was heated to 80° C. for approximately 8 hours. A silicon hydride terminated polyimide-siloxane copolymer having no olefinic unsaturation was obtained as shown by the NMR spectrum. 1 part of the platinum-containing silicon hydride terminated siloxane-imide copolymer and 0.020 parts of 1,3,5-
A mixture was prepared using trivinyl-1,1,3,5,5-pentamethyltrisiloxane. The resulting mixture was heated to 150°C for 2 hours. A cured silicone-polyimide elastomer was obtained. Example 2 9.81 g (5×10 ⁻² mol) norbornene dicarboxylic acid monomethyl ester, 9.66 g (2.5×10 ⁻² mol) benzophenonetetracarboxylic acid dimethyl ester and 9.91 g (5×10 ⁻² mol) 4,
A solution of 4'-methylene dianiline in 100 ml of dehydrated methanol was refluxed for 3 hours. After removing the methanol, the residue was heated at 150 °C in a nitrogen stream.
The mixture was heated for 2 hours. The product obtained was dissolved in 50 ml of chlorobenzene and poured into 400 ml of methanol. 23.6 g of oligoimide was obtained, ie, a yield of 98%, which was washed with methanol and dried. The product obtained based on the manufacturing method had the following formula: 1.17 g of the above oligoimide and 7.34 g of silicon hydride-terminated dimethylpolysiloxane (molecular weight 5300)
In a solution dissolved in 40 ml of dehydrated chlorobenzene, 5
A drop of 5% platinum complex mixture was added. Mixture at 80℃
The mixture was heated for about 8 hours. The resulting mixture was free of olefinic unsaturation as shown by the NMR spectrum. Removal of the solvent yielded a sticky silicon hydride terminated siloxane-imide block copolymer. Following the procedure of Example 1, 100 parts of the above silicon hydride terminated siloxane-imide block copolymer and 5 parts of 1,3,5-trivinyl-1,1,3,
A mixture of 5,5-pentamethyltrisiloxane
Heat to 150°C for 2 hours. Cured siloxane
An imido block copolymer elastomer is obtained. Example 3 13.68 g of 5-norbornene-2,3-dicarboxylic anhydride and 43.33 g of 2,2-bis[4-(3,
A mixture of 4-dicarboxyphenoxy)phenyl]propane dianhydride was added to a solution of 13.51 g m-phenylenediamine and 100 ml o-dichlorobenzene under nitrogen over 10 minutes. The resulting solution was heated to reflux for 2 hours, during which time water was continuously removed azeotropically. The resulting solution was poured into 400 ml of methanol and stirred vigorously. The precipitated product was filtered, washed with methanol and dried. Based on the method of preparation, the product had the following formula: 64.8 g of the above norbornene-terminated polyetherimide was obtained, representing a yield of 97%. In a nitrogen atmosphere, Karstedt's U.S. patent no.
5 drops of 5% platinum catalyst prepared according to No. 3775442,
Added to a mixture of 22.0 g of the above norbornene terminated polyetherimide, 4.0 g of 1,1,3,3-tetramethyldisiloxane and 40 ml of dehydrated chlorobenzene. The solution was stirred and heated to 70°C for approximately 12 hours. Carbon black was added to the resulting solution at room temperature and the mixture was stirred for 30 minutes. The mixture was then filtered and poured into 200 ml of dry diethyl ether with vigorous stirring. The resulting precipitate was filtered, washed with diethyl ether and dried.
Based on the manufacturing method, the resulting precipitate is a silicon hydride terminated polyetherimide with the following formula, and the yield is
Obtained at 98%. The identity of the product was further confirmed by NMR and IR analysis. 1.2 g of the above silicon hydride terminated oligoimide, 1
A mixture consisting of a drop of the platinum catalyst of Example 1, 10 ml of chlorobenzene, and 12 g of vinyl chain-terminated polydimethylsiloxane (average molecular weight about 18,000) was heated to 80° C. for about 12 hours under substantially anhydrous conditions.
When the solvent is evaporated, the intrinsic viscosity in chloroform is
A cam-like residue of 0.44 at 25°C was obtained. Based on the method of preparation and NMR data, the product was a vinyl chain-terminated polydimethylsiloxane-polyimide block polymer having the formula: A mixture of 10 g of the silicone-polyimide block polymer described above and 3 g of methylhydrogen fluid having a molecular weight of about 30,000 and a chemically bonded methylhydrogen siloxane content of 3.5% by weight was heated to 80° C. under vacuum in a furnace for 12 hours.
heated for an hour. A tough silicone-polyimide elastomer was obtained. Although the above examples refer only to a few of the vast number of variables that can be used to prepare the curable siloxane-imide block copolymers of the present invention, the present invention can be applied to a very wide variety of thermal It should be understood that the present invention relates to curable platinum-containing siloxane-imide block copolymers and methods of making the same.

Claims (1)

Claims: 1. A thermosetting composition containing a norbornene-terminated polyimide, a silicon hydride compound, and an effective amount of a platinum catalyst. 2. The thermosetting composition according to claim 1, wherein the norbornene-terminated polyimide is norbornene-terminated polyetherimide. 3. The thermosetting composition according to claim 1, wherein the silicon hydride compound is a silicon hydride siloxane.