EXCIMER LASER PHOTOLYSIS STUDIES OF PHOTOINDUCED AGGREGATION IN POLYMERS CONTAINING SPIROPYRAN UNITS.

Summary form only given. A laser time-resolved transient absorption study is made of the photoprocesses occurring in polymer and monomer and solutions of SP for better understanding of the fomation of the aggregation and quasi-crystal processes. It is shown that intrachain complexing of the triplet state of SP with the ground state chromophore leads to intrachain complexes AB. Aggregation of AB units or A units also occurs at much longer times and is redshifted. Steric effects in the polymer solution retard the isomerization of X and prevent complexing to AB.