Photoresponsive polymeric systems: 1. Mixed monomolecular films of some synthetic polymers and indolinospiropyrans

The properties of mixed monolayer films of photochromic indolinospiropyrans and poly(methylmethacrylate) (PMMA), poly(vinyl stearate) (PVSt), and poly(2-vinyl pyridine) (P2VP) have been studied. It was found that reversible photoinduced changes in monolayer surface-pressure with time occurred in collapsed systems and in mixed films in which the photochrome had been forced out of the polymer monolayer. Mixed films of P2VP and a spiropyran of particular structure could have their inherent stability increased under the action of ultraviolet irradiation on aqueous subphases. This effect appeared to be related to the formation of a physically crosslinked photomerocyanine-polymer two-dimensional network.