A photochromic p,p'-bis(chloromethyl)azobenzene (CAB) was prepared as a crosslinking agent. Three poly(tertiary aminostyrene)s prepared via living anionic polymerization were used as reactive polymers: poly(N,N-dimethyl-4-vinylphenylamine) (PPA), poly(N,N-dimethyl-4-vinylbenzylamine) (PBA) and poly((N,N-dimethyl-4-vinylphenethylamine) (PPTA). Films were cast from tetrahydrofuran solution of CAB and the polymers. The crosslinking reaction proceeded during the evaporation of solvent and the annealing of the films at 90°C for > 10 h. The result of the swelling test led us to conclude that all the CAB added to the polymer was consumed in the crosslinking reaction. Photochemical isomerization was studied for CAB incorporated in three polymers by cross linkage. The conversions for photochemical isomerization of CAB in three crosslinked films were 35-10% in the stationary state under u.v. irradiation below the glass transition temperature. This indicated that the thermal freedom of CAB was depressed by crosslinking in the glassy state.
Посилання на статтю:
Photochemical isomerization of p.p'- bis ( chloromethyl ) azobenzene incorporated in poly (tertiary aminostyrene) s by cross linkage / Masato Kijima*, Kazunori Set and Teruo Fujimoto // Polymer. – 1992. – Vol 33. – P. 2402-2407.