Polyimide preparation from imido acyl halide

Claim 2

In a process of producing a polyimide prepolymer, the step which comprises reacting a difunctional amine with an acid halide of the formula ##STR14## in which Hal is halogen, the group of the formula ##STR15## is an unsaturated dicarboxylic acid imido group, and the group of the formula --R 3 --CO-- is an acyl group attached to the imido nitrogen atom, to yield a polyimide prepolymer convertible by heating into a macromolecular polyimide.

Claim 3

The process of claim 1, in which the difunctional amine and the unsaturated dicarboxylic acid imido acid halide are reacted in the molar proportion between about 1:1 and about 1:2 at a temperature not substantially exceeding 100° C.

Claim 4

The process of claim 1, in which the reaction of the difunctional amine and the unsaturated dicarboxylic acid imido acid halide is carried out in a substantially inert, water-immiscible organic solvent of a boiling point not substantially exceeding 100° C. in the presence of a tertiary amine as acid binding agent.

Claim 5

The process of claim 3, in which the substantially inert, water-immiscible organic solvent is methylene chloride.

Claim 6

In the process of claim 3, the additional steps of introducing the resulting reaction mixture, while stirring, into water heated to a temperature above the boiling point of the solvent at a speed to cause simultaneous distillation of the solvent and precipitation of the polyimide prepolymer, and of separating the precipitated prepolymer from the resulting aqueous phase.

Claim 7

In the process of claim 4, the additional steps of introducing the resulting reaction mixture, while stirring, into water heated to a temperature above the boiling point of methylene chloride at a speed to cause simultaneous distillation of the methylene chloride and precipitation of the polyimide prepolymer, and of separating the precipitated prepolymer from the resulting aqueous phase.

Claim 8

The process of claim 1, in which the difunctional amine is an amine of the formula H.sub.2 N--R.sub.3 --NH.sub.2 in which R 3 is a member selected from the group consisting alkylene with 1 to 12 carbon atoms, cycloalkylene with 5 to 6 carbon atoms, a heterocyclic member with 4 to 5 carbon atoms and at least one oxygen, nitrogen, or sulfur atom in the heterocyclic ring, a monocarboxylic or dicarbocyclic aromatic member, at least two monocarbocyclic or dicarbocyclic aromatic or cycloalkylene members connected to each other by a carbon to carbon bond or by a divalent member selected from the group consisting of oxygen, sulfur, alkylene with 1 to 3 carbon atoms, and the groups of the formulas ##STR16## in which R 4 , R 5 , and R 6 are members selected from the group consisting of alkyl with 1 to 6 carbon atoms, cycloalkyl with 5 to 6 carbon atoms, monocarbocyclic aryl, and dicarbocyclic aryl; and R 7 is a member selected from the group consisting of alkylene with 1 to 12 carbon atoms, cycloalkylene with 5 to 6 carbon atoms, monocarbocyclic arylene, and dicarbocyclic arylene.

Claim 9

The process of claim 1, in which the acid halide is an acid halide of the formula ##STR17## in which R is a member selected from the group consisting of an unsaturated member of the formulas ##STR18## in which R 8 , R 9 , and R 10 are members of the group consisting of hydrogen and alkyl with 1 to 6 carbon atoms, Hal is halogen, and R 3 is the member indicated in claim 7.

Claim 10

The process of claim 1, in which the difunctional amine is 4,4'-diamino diphenyl methane and the acid halide is m-maleimido benzoylchloride.

Claim 11

The process of claim 1, in which the difunctional amine is 4,4'-diamino diphenyl methane and the acid halide is p-maleimido benzoylchloride and in which the molar proportion between amine and acid chloride is about 0.7:1.0.

Claim 12

The process of claim 6, in which the difunctional amine is 4,4'-diamino diphenyl methane and the acid halide is m-maleimido benzoylchloride.

Claim 13

The process of claim 11, in which the molar proportion of difunctional amine to acid chloride is about 0.6:1.

Claim 14

The process of claim 1, in which the difunctional amine is 4,4'-diamino diphenyl sulfone and the acid halide is m-maleimido benzoylchloride.

Claim 15

The process of claim 1, in which the difunctional amine is m-phenylene diamine and the acid halide is p-maleimido benzoylchloride.

Claim 16

In a process of producing a macromolecular, cross-linked, infusible polyimide resin being substantially insoluble in organic solvents, the step which comprises heating the polyimide prepolymer obtained according to the process of claim 1 until polymerization is completed.

Claim 17

The process of claim 15, in which the prepolymer is heated at a temperature between about 80° C. and about 400° C.

Claim 18

The process of claim 16, in which the polyimide prepolymer is heated under pressure.