Comparison of the photochromic properties of fulgides and fulgimides

Photochromic properties of some arylfulgimides such as furyl-, thienyl-, and thiazolylfulgimides were compared with corresponding fulgides in detail. Photochemical reversibility and thermal stability as well as the photochromic response of fulgimides were substantially comparable with those of the fulgides, both in solution and in solid polymer film. Fulgimides revealed high resistance to solvolytic degradation in hydroxylic media while corresponding fulgides underwent rapid degradations. Thus, N-(4-carboxyphenyl)fulgimide, being soluble in aqueous media, revealed moderate photochromic performance in aqueous ethanol solution without extensive solvolytic degradation, as well as in ionic polymer film of allylamine hydrochloride. (C) 1997 Elsevier Science S.A.