Synthesis,characterization and thermooxidative stability of addition polymers from 1,4,5,8-tetrahydro-1,4;5,8-diepoxyanthracene and anthracene end-capped imide oligomers

A series of Diels–Alder addition-type copolymers prepared from 1,4,5,8-tetrahydro-1,4;5,8-diepoxyanthracence and anthracene end-capped 6F-PDA imide oligomers were characterized. The composition of the anthracene end-capped imide oligomers was found to be sensitive to monomer molar ratios and the mode of monomer addition. The resistance of the copolymer to thermooxidative degradation at 316 and 371°C was compared with a similar commercial polymer called Avimid-N prepared from 4,4′-hexafluoroisopropylidene-2,2′ bis(phthalic acid anhydride) and para-and meta-phenylene diamine, abbreviated 6F-PDA. There are strong indications that the copolymers undergo degradation initially by unzipping the diepoxyanthracene unit from the anthracene end-capped 6F-PDA oligomer unit (Avimid-N like repeat unit), followed by a slower degradation of the more stable residual 6F-PDA unit. © 1993 John Wiley & Sons, Inc.