PREPREG Russian patent published in 1995 - IPC

FIELD: production of composite polymer materials. SUBSTANCE: proposed nonporous prepreg is manufactured as fibrous base which is impregnated with concentrated solution of polyamide acid on the base of pyromellitic dianhydride or diester of pyromellitic acid and diamine. Said polyamide acid has common formula H₂N-Q-NH₂ where Q is organic radical being chosen of group which includes where G is oxygen or sulfur, Z is hydrogen or phenyl, if Z is hydrogen then amino groups of diamine are in ortho- or in meta position to G, if Z is phenyl then said groups are in meta- or in para position to G; where G is oxygen or sulfur, R is phenyl, diphenyl or naphthyl; where G is oxygen or sulfur, amino groups are displaced in ortho- or in meta position to G; ; or mixture thereof. Polyamide acid is prepared on the base of diamines being chosen of group which includes 1,3-bis-(2-aminophenoxy)benzine, 1,2-bis-(3-aminophenoxy)benzine, 1,2-bis-(2-aminophenoxy)benzine, 1,4-bis(2-aminophenoxy)benzine, 1,4-bis-(3-aminophenoxy)benzine, 1,3-bis(3-aminophenoxy)benzine, 2,4-diamino diphenyl ether, 1-(2,4-diamino phenoxy)naphthalene, 2-(2,4-diamino phenoxy)naphthalene, 2-(2,4-diamino phenoxydiphenyl, 1,4-bis-(4-aminophenoxy)-2-phenyl benzine, 2,2-bis-[4-(2-aminophenoxy)phenyl] propane, and 2,2-bis-[3,5-dichlor-4-(4-aminophenoxy)phenyl] propane. Polyamide acid is prepared on the base of mixture 1,3-bis-(3-aminophenoxy)benzine and 2,2-bis-[4-(4-aminophenoxy)phenyl] propane. Content of volatile compounds in proposed prepreg is not more 20 of its total mass. EFFECT: improves quality of desired product. 3 cl, 1 tbl