IMIDE OLIGOMERS AND CO-OLIGOMERS CONTAINING PENDENT PHENYLETHYNYL GROUPS AND POLYMERS THEREFROM

摘要

Controlled molecular weight imide oligomers and co-oligomers containing pendent phenylethynyl groups (PEPIs) and endcapped with nonreactive or phenylethynyl groups have been prepared by the cyclodehydration of the precursor amide acid oligomers or co-oligomers containing pendent phenylethynyl groups and endcapped with nonreactive or phenylethynyl groups. The amine terminated amide acid oligomers or co-oligomers are prepared from the reaction of dianhydride(s) with an excess of diamine(s) and diamine containing pendent phenylethynyl groups and subsequently endcapped with a phenylethynyl phthalic anhydride or monofunctional anhydride. The anhydride terminated amide acid oligomers and co-oligomers are prepared from the reaction of diamine(s) and diamine containing pendent phenylethynyl group(s) with an excess of dianhydride(s) and subsequently endcapped with a phenylethynyl amine or monofunctional amine. The polymerizations are carried out in polar aprotic solvents such as N-meth yl- 2-pyrrolidinone and N,N-dimethylacetamide under nitrogen at room temperature. The amide acid oligomers or co-oligomers are subsequent ly cyclodehydrated either thermally or chemically to the corresponding imide oligomers. The polymers and copolymers prepared from the se materials exhibit a unique and unexpected combination of properties that includes higher glass transition temperatures after curin g and higher retention of neat resin, adhesive and carbon fiber reinforced mechanical properties at temperatures up to 204 .degree.C under w et conditions without sacrificing melt flow behavior and processability as compared to similar materials. These materials are useful as adhesives, coatings, films, moldings and composite matrices.