SYNTHESIS OF SOLAR-ENERGY STORAGE-EXCHANG E POLYMER CONTAINING CHALCONE TYPE NORBORNADIENE MOIETY AND PHOTOCHEMICAL-REACTION OF THE RESULTING POLYMER

A chalcone type norbornadiene (NBD) derivative was prepared by Diels-A lder reaction of cyclopentadiene with an acethylene compound which was synthesized from 4'-hydroxychalcone. Chalcone type NBD polymer was sy nthesized by the resulting NBD derivative with poly(p-chloromethylstyr ene). The photochemical reaction of the polymer thus obtained was eval uated in the film state. The photochemical valence isomerization of th e chalcone type NBD polymer proceeded to produce the corresponding qua dricyclane (QC) groups with 60 second irradiation with a 500 W-xenon l amp. Furthermore, it was found that the rate of photochemical valence isomerization of the chalcone type NBD polymer was higher than that of the other NBD polymers having phenyl or N-phenylcarbamoyl groups as c hromophores. The reversion from the QC groups to the NBD moieties in t he polymer was carried out using 5,10,15,20-tetraphenyl-21H,23H-porphi necobalto(II) (Co-TPP) as a catalyst in THF solution. The catalytic re version proceeded very smoothly. The thermal reversion from QC groups to NBD moieties in the film state also proceeded smoothly.