Photochromic network polymers

New photochromic polymers having network structure have been studied. These polymers have been obtained on the base of spiropyrans (SP) with one or tw o polymerizable groups. It has been shown that the photochromic properties of SP molecules Linked with macromolecules by one polymerizable group depen d on supermolecular structure of network polymer. So, these SP molecules ca n be used as indicators of microheterogeneity of network polymer. It has be en established that the photochromic behavior of SP molecules having two po lymerizable groups is determined by the number of chemical bonds (one or tw o) of such a SP molecule with macromolecule. The copolymers of these SP mol ecules with alkyl methacrylates are of special interest because using these copolymers make it possible to create photochromic polymer material having large and adjustable time of storage of optical information. (C) 1999 Else vier Science S.A. All rights reserved.