REACTION OF 9'-HYDROXY SPIRONAPHTHOXAZINE WITH COPOLYMER FROM GLYCIDYL METHACRYLATE AND PHOTOCHROMIC PROPERTIES OF THE REACTION-PRODUCT

The reaction of the photochromic spironaphthoxazine (TM-H-SNO) having 9'-substituted hydroxy group with epoxy groups of copolymer, glycidyl methacrylate and methyl methacrylate (GMA), was carried out, and photo chromic properties of the reaction product were investigated. A mixtur e of the copolymer (197 mmol to epoxy groups), TM-H-SNO (19.7 mmol) an d a catalyst, benzyltrimethylammonium chloride (19.7 mmol), in N,N'-di methylformamide (DMF) (100 ml) was heated at 57 similar to 75 degrees C. After purification, the reaction content of photochromic groups in the polymer was evaluated by NMR spectroscopy. The reaction apparently agreed with first order kinetics, and the apparentactivation energy w as about 25 kcal/mol. The film cast from a chloroform solution of poly mer containing higher reacted TM-H-SNO had an absorption band below 55 0 nm even before UV irradiation. After UV irradiation with 100 W high- pressure Hg lamp filtered at 365 nm for 1 min, the film gave the absor ption spectrum at about 606 nm. Its absorbance was lower than that exp ected from the reacted TM-H-SNO content. However, UV irradiation with the unfiltered lamp for 5 min gave absoption spectra at about 568 or 6 06 nm according to the solvent used to cast, and the absorbance was hi gher than the case of 1 min. These phenomena were considered from the points of view of aggregation in the reacted TM-H-SNO, which might con tain isomeric merocyanines, crosslinkage of the residual epoxygroups i n GMA by heating and its swelling by solvents.