关键词: 甲烷 P, 对苯二甲酸 P, 乙酸乙酯, 苯甲酸 P, 苯甲酸 P, 氢键, 异构化反应, 互变异构, 聚丁二烯, 紫外辐射

Photostabilizing behavior of 3 b-diketones (dibenzoylmethane, benzoylacetone, di-Et terephthaloyl acetate) was investigated. b-Diketones in solution exist in a thermal equilibrium via enol-keto tautomerism. Under UV-irradn., the absorption of enol form decreases, whereas the ketone form increases with increasing irradiation time. Due to the fact that 3 compounds have different tautomeric process and different ability of H bond formation, it could be expected that they have different ability for polymer stabilization. The result of photostabilization of dibenzoylmethane could not be explained by Otterstedt's mechanism. An alternative consideration was proposed.

Key words: METHANE P, P-BENZENEDICARBOXYLIC ACID P, ETHYL ACETATE, BENZENECARBOXYLIC ACID P, BENZENECARBOXYLIC ACID P, HYDROGEN BONDS, ISOMERIZATION REACTION, TAUTOMERISM, POLYBUTADIENE, ULTRAVIOLET RADIATION