PURPOSE: To obtain highly crystalline aromatic polyimides which are useful for the production of an injection-formable thermoplastic resin and a composite material with carbon fibers or glass fibers and which contain alkylene disulfide groups having resistance against a strong solvent such as chlorinated hydrocarbons.
CONSTITUTION: The crystalline aromatic polyimides contain alkylene disulfide groups and consist of chemically bonded units expressed by formula I, wherein R2 is a bivalent 1 to 10C alkylene; R3 is a bivalent 6 to 27C aromatic hydrocarbon group which may have substituents with inert groups during condensation. The polyimides are produced by hydrolyzing a new substance expressed by formula II (R1 is a univalent 1 to 14C org. group; R is same as R2) to obtain a tetra acid, then dehydrating and cyclizing the tetra acid to obtain a new substance expressed by formula III, and then allowing the obtd. substance to react with a compd. expressed by NH2R3NH2. The new substance of formula II is obtd. by allowing a compd. expressed by formula IV (X is a halogen) to react with a compd. expressed by M2S (M is an alkali metal) to obtain a compd. expressed by formula V, and then allowing the compd. of formula V to react with a compd. expressed by XRX.
PATORISHIA PAIKU ANDAASON
TOMASU REEN EBANZU
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