Patent ID: 6593389
Filing Date: 2003-07-15
Classification: C08G

Abstract:
Polyimides derived from the photochemical cyclopolymerization of approximately stoichiometric amounts of at least one(a) aromatic diketone selected from the group consisting of wherein Ar is the same or a different aromatic or substituted aromatic radical and R is the same or a different radical selected from the group consisting of aromatic radicals, O2CR1 and â€”OR2 radicals wherein R1 and R2 are the same or different radicals selected from the group consisting of lower alkyl radicals of 1 to 8 carbons and aryl radicals, and X is selected from the group consisting of nil, oxygen, sulfur, C&boxH;O, alkyl radicals of 1 to 8 carbons, ether radicals, ester radicals, and aryl radicals with at least one (b) dienophile selected from the group consisting of bismaleimides, trismaleimides and mixtures of maleimide endcap with bismaleimide and/or trismaleimides, wherein the maleimides range from 0 to about 25 molar percent of the mixture, to obtain polyimides having glass transition temperatures (Tg) ranging up to about 300Â° C., high thermal-oxidative stability and decomposition-stability temperatures ranging up to about 350Â° C.