FIBROUS REINFORCED-RESIN COMPOSITES AND METHODS FOR THE PRODUCTION THEREOF

1376137 Synthetic resin composites GENERAL ELECTRIC CO 12 Nov 1971 [12 Dec 1970] 52765/71 Heading C3R [Also in Division D1] A powdered or granular resin used for impregnating a multifilament roving by a fluidized bed technique may comprise a thermosetting polyimide or modified polyimide resin as disclosed in Specification 1,190,718. The resin may be a modified polyimide prepolymer such as a N-phenyl maleiimide, pyromellitimide diamine reaction product or the reaction product of an N,N1-bis-imide of Formula I where R1 is a divalent group having a carbonto-carbon double bond and R is a divalent group having at least two carbons, and a diamine of Formula II: H 2 N-R-NH 2 wherein R is a divalent group (#30C), e.g. the reaction product of N,N1-bis-maleimido-(4,41-diphenylmethane) and 4,41-diaminodiphenylmethane or methylenedianiline. The roving after passage through the fluidized bed, is subjected to high frequency vibrations to distribute the resin evenly over the filaments. The impregnated roving may be heated to fuse and cure the resin into a continuous coating encapsulating the filaments. The filaments may be chopped to a suitable length for moulding.