PURPOSE: To obtain the aromatic polyamide oligomer useful for producing an aromatic polyamide excellent in moldability, mechanical strength, etc., by thermally reacting a specified aromatic polycarboxylic acid, a specified compound and an aromatic diisocyanate.
CONSTITUTION: An aromatic polycarboxylic acid comprising an adduct of an aromatic polyamine with an aromatic polycarboxylic acid anhydride or an adduct of an aromatic tribasic or higher carboxylic acid anhydride with a polymerizable unsaturated compound having active hydrogen atoms (e.g. a compound of formula II obtained from an aromatic polyamine of formula I and trimellitic anhydride) is thermally reacted with a polymerizable unsaturated compound having active hydrogen atoms or a cyclic unsaturated acid anhydride (e.g. methacrylic acid) and an aromatic diisocyanate (e.g. tolylene 2,4- diisocyanate) to give an aromatic polyamide oligomer of formula III.
NAKAJIMA HIROSHI
SHIMIZU AKIHIRO
