Cross Reference to Related Applications

References is made to my copending application BD-14198, for Silylnorbornane Anhydrides and Method for Making filed concurrently herewith and assigned to the same assignee as the present invention.

Background of the Invention

The present invention relates to organopolysiloxane-polyimide copolymers based on the use of norbomane anhydride terminated organo polys iloxane and organic dia ine.

Prior to the present invention, as shown by

Holub, U.S.. Patent 3 ,325 ,450 , and Heath et al, U.S. Patent 3 ,847,867, silicon-polyimide copolymers were prepared by the reaction of aromatic bis (anhydride) s and amine ofgano-terminated polydiorganosiloxanes. For exam- pie, Ξolub shows the use of aminopropyl polydimeth lsi- loxane and amine bu ty It etrame thy Id is iloxane , as well as the employment of other diamines, for example , meta- pheny lenediamine . The production of such silicone- polyimide block polymers provide valuable compositions

SUBSTITUTE SHEET "BU RtAT

OMPI

useful for example , as high temperature resistant electr¬ ical insulation.

As shown by copending application RD-14198 , norbornane-terminated polydiorganosiloxane of the for¬ mula.

where R is selected from C^^ mσnovalent hydrocarbon radicals and substituted C ₍₁ _ ₁₃₎ monovalent hydrocarbon

radicals, ^- ^ are selected from hydrogen, halogen and the same or different G monovalent hydrocar on rad¬

icals and substituted C^^ _j monovalent hydrocarbon rad¬ icals, Z is a divalent radical selected from -O- and

-C(R ⁾ _-. 7 is a radical selected from R and

n is an integer equal to 0 to 2000 inclusive, m is a whole number equal to 0 to 500, and the sum of n+m is equal to 0 to 2000 inclusive, can be made by the

-BUREAU

SUBSTITUTE SHEET OMPI

hydrosilation of norbornene anhydride and derivatives thereof and a silicon hydride in the presence of a plat- ^' num catalyst as shown by the following equation:

Formula (1)

where R^-R ⁶ , Z and n are as defined above.

Radicals included within R are , for example aryl radicals and halogenated aryl radicals , for example , phenyl, chlorophenyl,- tolyl, xylyl, biphenyl, naphthyl, etc. ; alkenyl radicals , for example, vinyl, allyl, cyclohexenyl, . etc ; C, _1-8j alkyl radicals and halogenated alkyl, for example, methyl, ethyl, propyl, butyl, octyl, etc.

Radicals included within R^- ⁶ are, for example hydrogen, cnloro, and R radicals as defined above.

Another procedure shown in copending applica¬ tion RD-14198 is by equilibrating a dianhydride within the scope of formula (1) where n is less than 2000 with a cyclic organopolysiloxane , for example octame hylcyclo- tetrasiloxane in the presence of an acid catalyst, for example su I uric acid.

SUBSTITUTE SHEET

The present invention is based upon the discovery that silicone-polyimide copolymers having sup ^e ¬ rior thermal oxidative stability and unusually high heat distortion temperatures can be made by effecting reaction between norbomane anhydride-terminated polydiorganosi- loxane of formula (1) and organic diamine of the formula,

NH ₂ R'NH ₂ (2)

and optionally with organic dianhydride of the formula ,

where Q is a tetravalent organo radical selected from tha class consisting of

and nox

^ ^@ — €

where D is a member selected from

SUBSTITUTE SHEET

-fU RhA t OMPI

-O- , -S- , -CNR ⁷ NC- , -C- , , -OR ⁹ 0- and COR ⁹ OC-

R ⁸

where R ⁸ is selected from hydrogen and R, R ⁹ is a member selected from the class consisting of

and divalent organic radicals of the general formula.

where X is a member selected from the class consisting of divalent radicals of the formulas.

O

"y ^H 2y~ t ^~ ^ ^~ t #-S-, and -S-

where m is 0 or 1, y is a whole number from 1 to 5, R ⁷ is

SUBSTITUTE SHEET

a divalent ^c t2-20 ₎ ^or ? ^anic radical selected from the class consisting of (a) aromatic hydrocarbon radicals having from 6-20 carbon atoms and halogenated derivatives thereof, (b) alkylene radicals and cycloalkylene radicals having from 2-20 carbon atoms, C,2-8 ₎ alkylene terminated polydiorganosiloxane, and (c) divalent radicals included by the formula,

Q' is a member selected from the class consisting of

O o -O- , -C- , -S- -S- , and -C^- n

0

x is a whole number from 1 to 5 inclusive.

Statement of the Invention

There is provided by the present invention, silicone-polyi ide copolymers comprising norbomane ter* minated polydiorganos iloxane of the formula

SUBSTITUTE SHEET

where R-R , Z, m and n are as previously defined and Y' is selected,from R and a group having the formula,

Some of the silicon-imide copolymers which are included within the present invention comprise norbomane terminated polydiorganosiloxane of the formula, '

chemically combined with polyimide of the formula,

SUBSTITUTE SHEET

OMPI

8 -

where R-R ⁷ , n, 0, and Z are as previously defined, and a is an integer equal to 1 to 1000 inclusive, b is a whol. number equal to 0 to 200 inclusive and the sum of a+b is equal to 1 to 1000 inclusive.

' Organic dianhydrides of formula (3) which can be utilized- in the practice of the present invention in combination with the norbornene anhydride-terminated siloxanes of formula (1) are, for example, pyromellitic dianhydride, benzophenone dianhydride, aromatic bis(ether anhydride)s of Heath et al, U.S. Patent 3,879,428, assigned to the same assignee as the present invention, dianhydride of the formula,

and mixtures thereof, where R ⁷ and R ⁸ are as previously defined.

Included within the organic diamines of formula (2) _ure compounds such as ^'

m-phenylenediamine;

p-phenylenediamine;

SUBSTITUTE SHEET

- 9 -

4,4'-diaminodiphen lpropane;

4,4'-diaminodiphenyl ethane;

benzidine;

, ' -diaminodipheny 1 sulfide;

4 ,4' -diaminodipheny 1 sulfone;

4, 4' -diaminodipheny 1 ether;

1,5-diaminonaphthalene ;

3,3 * - imeth lbenzidine ;

3 , 3 ' -d ime thoxybenz id ine ;

10 2,4-diaminotoluene;

2, 6 ^* -diamino toluene ;

2,4-bis(p- -amino-t-butyl) toluene;

l,3-diamino-4-isopropyIbenzene;

1,2-bis(3-aminopropoxy).ethane;

15 st-xyly lenediamine ;

p-xyl lene iamine j

bis ( 4-aminocyclohexyl) ethane ;

deca e thy lenediamine ;

SUBSTITUTE SHEET

OMPI

A,

3-methylhe tame hylenediamine ;

4 ,4-dime thy Ihe tame th lenediamine ;

2 ,11-dodecanediamine ;

2 ,2-dime thy lpropy lenediamine ;

5 octame thy lenediamine ;

3-methoxyhexame thy lenediamine ;

2, 5-dimethylhexame thy lenediamine ;

2 ,5-dime thy Iheptam thy lenediamine ;

3-methylheptamethylenediamine ;

10 5-methylnonamethy lenediamine ;

1, -cyclόhexanediamine;

,15-octadecanediamine;

bis(3-aminopropyl)sul ide;

r-methyl-bis (3-aminopropyl) amine ;

15 hexaroe thy lenediamine ;

hep tame th lenediamine ;

2,4-diaminotoluene ;

noname thy lenediamine ;

SUBSTITUTE SHEET

OMPI

2 , 6-diaminotolnene ;

bis- (3-aminopropyl) etramethyldisiloxane , etc .

The silicone-polyimide copolymers can be syn¬ thesized by a two-step procedure involving the reaction at ambient temperatures in the presence of an inert organic solvent of substantially equal molar amounts of the organic diamine of formula (2) and norbomane ter¬ minated polydiorganosiloxane of formula (1) , or option¬ ally with organic dianhydride with formula' (3) , where the total moles of organic diamine and dianhydride are sub¬ stantially the same . The intermediate polyamic acid ini¬ tially formed at room temperature is followed by cyclo- dehydration at elevated temperatures, for example , from 150°C to 220°C

Another procedure which can be used to make the silicone-imide copolymers is by refluxing substantially equal molar amounts of the organic diamine of formula (2) and the norbomane dianhydride and optionally other ^' organic dianhydride in an inert organic solvent, for example, o-dichlorobenzene, me ta -ere sol, etc.

Dipolar aprotic solvent, for example dime thy 1- forma ide , dimethylacetamide , N-methylpyrrolidone , can be used to prepare prepolymers. The proportions of norbor- nane anhydride-terminated polydiorganosiloxane with at least one other organic dianhydride in various molar

SUBSTITUTE SHEET

proportions can be reacted with a substantial equal molar amount or organic diamine to produce a wide variety of silicone-polyimide block polymers.

The- silicon-poly i ide copolymers of the present invention can be used as insulation for electrical con¬ ductors, adhesives, molding compounds, coatings, for mak¬ ing _. laminates and tough elastomers

In order that those skilled in the art will be better able to practice the invention, the following example is given by way of illustration and not by way of limitation. All parts are by weight.

!

Example

There was added 10 drops of a 5% platinum cat¬ alyst prepared in accordance with -Karstedt, U.S. 3 ,775 ,442 , assigned to the same assignee as the present invention, to a mixture while it was being stirred of 69.4 g (0.42 mole) of 5-norbornene-2 ,3-dicarboxylic .acid anhydride, 26.8 g (0.2 mole) 1,1 ,3 ,3- te trame thy Idis iloxane and 100 ml of dry chlorobenzene . The resulting mixture was heated with stirring to 70-80°C for 4 hours and then 100-110°C overnight. After cooling, carbon black was added and the solution was stirred for 30 minutes at room temperature. Filtration, removal of the solvent at 100°C with a vacuum pump and addition of dry diethylether resulted in the precipitation of a white

SUBSTITUT E - SHEET

-BU REA

OMPI

crystalline solid. Based on method of .preparation , the product was 5 ,5 ' - (1 ,1 ,3 ,3-tetrameth 1-1 ,3- disiloxanediyl) -bis-norbornane-2 ,3-dicarboxylic anhydride having the formula.

A series of silicon-imide. copolymers including block copolymer-s were prepared .from various mixtures of the above 5 ,5 '> (l ,l ,2 ,3-tetramethyl-l ,3-dis iloxanedyl) - bis-norbornane-'2 ,3-dicarboxylic dianhydride , hereinafter referred to as (NSDA) , and benzophenone tetracarbox lic dianhydride (BPDA) •.

There was added to a solution of 0.991 grams

(5 x 10"" ³ moles) of methylene dianiline and 5 ml of dimethylformamide while it was stirred under nitrogen, a

mixture of 0.457 grams (10" ³ mole) of NSDA, 1.289 grams

(4 x 10 mole) of BPDA and 5 ml of dimethylformamide. The resulting solution was stirred for 2 hours at room temperature. There was obtained a silicone-amide acid copolymer. The solution was then poured into a glass dish and dried at 80°C for 1 hour , . and 150°C for 2 hours in an oven cast under flowing nitrogen. Based on method

SUBSTITUTE SHEET

of preparation , IR and NMR analysis , there was obtained a- siϊicone-poly copolymer consisting essentially of norfo- . - nane terminated dimethyls iloxane groups of the formula .

chemically combined with imide groups having the formula .

The same procedure was repeated to prepare an additional silicαne— imide block polymers within the - scope of formula (1) as shown by the following formula:

SUBSTITU rε SHEET

O

Glass transition temperatures (Tg) of the copo¬ lymers were measured by differential scanning calorimetry (DSC) and are shown in the following table, where b, c and d values in the above formula are shown. ^' Thermal - oxidative stabilities of the copolymers were measured by thermogravimetric analysis (TGA) . Ten percent weight loss temperatures of the copolymers under N- and air are

also showiv:

SUBSTITUTE SHEE

TGA C °C)

^N 2 Air

Tg (°C) 10 % 10% b c d (DSC) loss loss

0 0 10 270 550 530

1 2 8 243 515 520

1 5 5 233 495 _. 490

1 . 8 2 183 490 475

1 10 0 163 505 505

13 1 9- 256 530 545

25 1 9 271 510 490

.66 1 9 278 530 515

The above results show that the ^' silicone-imide copolymers of the present invention can be used as high temperature insulation for metallic conductors which possesses superior oxidative stability. Por example, a copper wire is dipped into a dimethylformamide solution of the silicone-amic acid copolymer and removed from the solution and allowed to air dry. The coated wire is then heated to 2Q0°C to convert the amide acid coating on the wire to the imide state. The resulting silicone-imide copolymer coating is superior high temperature insulation possessing superior oxidative stability.

. Although the above example is directed to only a few of the very many variables of the silicone-imide copolymers of the present invention, it should be under¬ stood that the present invention is directed to a much

SUBSTITUTE SHEET

broader variety of such silicone-imide copolymers includ¬ ing block copolymers , based on the employment of norbor- nane anhydride-terminated polydiorganosiloxane of formula (1) with organic diamine of formula (2) and optionally with mixtures of norbomane anhydride-terminated polydiorganosiloxane of formula (1) and other organic dianhydrides of formula (3 ) as previously taught in the description preceding these examples.

BUR £4

SUBSTITUTE SHEET -«K