Siloxane-containing polyimide coatings for electronic devices

Claim 3

A method for preparing silicon-containing polyimide as recited in claim 1 wherein R' is ##STR17##

Claim 4

A method for preparing silicon-containing polyimide as recited in claim 1, further comprising aromatizing the Diels-Alder adduct by heating in acidic medium.

Claim 5

A method for preparing silicon-containing polyimide as recited in claim 2, wherein said aromatizing and said refluxing of said Diels-Alder adduct is in an acid selected from the group comprising acetic anhydride or glacial acetic acid.

Claim 6

A method for preparing silicon-containing polyimide as recited in claim 1 wherein said polymerizing of said bis-furan and bis-maleimide is by refluxing for 5-10 hours at 60-80 degrees C. in the presence of tetrahydrofuran.

Claim 7

A method for preparing silicon-containing polyimide as recited in claim 5 wherein said refluxing of said bis-furan and bis-maleimide is under nitrogen.

Claim 8

A silicon-containing polyimide useful as a conformal coating and formed as a product of a Diels-Alder reaction comprising the steps of (a) combining a siloxane-containing bis-furan derivative with a bis-maleimide in the presence of an inert solvent wherein the bis-furan derivative is of the general formula: ##STR18## wherein X n is a divalent bridging group linked through position 2 or 3 of the furan rings, where n is 0 or 1, each R', R" and R"' is hydrogen or a hydrocarbon radical of 1 to 6 carbon atoms, and R is a polydimethyl siloxane segment of the general formula: ##STR19## where m is 1-10; (b) polymerizing said mixture by heating in an inert solvent, and (c) aromatizing said polymer by heating in acid to form a polyimide having the general formula: ##STR20## where X n is a divalent bridging group with n is 0 or 1, R is a siloxane segment of the general formula: ##STR21## with m is 1-10, and R' is a divalent group of four or more carbon atoms, or said divalent group containing R units.

Claim 9

A silicon-containing polyimide useful as a conformal coating and formed as a product of a Diels-Alder reaction comprising the steps of (a) combining a siloxane-containing bis-furan derivative with a bis-maleimide in the presence of an inert solvent wherein the bis-furan derivative is of the general formula: ##STR18## wherein X n is a divalent bridging group linked through position 2 or 3 of the furan rings, where n is 0 or 1, each R', R" and R"' is hydrogen or a hydrocarbon radical of 1 to 6 carbon atoms, and R is a polydimethyl siloxane segment of the general formula: ##STR19## where m is 1-10; (b) polymerizing said mixture by heating in an inert solvent, and (c) aromatizing said polymer by heating in acid to form a polyimide having the general formula: ##STR20## where X n is a divalent bridging group with n is 0 or 1, R is a siloxane segment of the general formula: ##STR21## with m is 1-10, and R' is a divalent group of four or more carbon atoms, or said divalent group containing R units.

Claim 10

A silicon-containing polyimide useful as a conformal coating and formed as a product of a Diels-Alder reaction as in claim 7 wherein said polymerizing is conducted by heating in an inert solvent at a temperature of 60-80 degrees C. for 5-7 hours, or until polymerization is completed.

Claim 11

A silicon-containing polyimide useful as a conformal coating and formed as a product of a Diels-Alder reaction as in claim 7 wherein said aromatizing is by refluxing in an acid selected from the group comprising acetic anhydride or glacial acetic acid.

Claim 12

A silicon-containing polyimide useful as a conformal coating and formed as a product of a Diels-Alder reaction as in claim 7, wherein said siloxane containing bis-furan derivative has the general formula: ##STR22## wherein X n is a divalent bridging group linked through position 2 or 3 of the furan rings, where n is 0 or 1, each R', R" and R"' is hydrogen or a hydrocarbon radical of 1 to 6 carbon atoms, and R is a polydimethyl siloxane segment of the general formula: ##STR23## with m is 1-10.