Gezielt abbaubare Polymersysteme: Synthese und Degradationsmechanismen

Polymers containing UV-labile groups were prepared and decomposition by UV irradiation with low dose rates was examined. Two different degradation principles were used: direct cleavage of triazene groups and catalytic reaction of carbonate groups with a strong acid. The reaction of the UV labile group and the change of the mechanic properties due to the reaction were analyzed. In contrast to high dose rates no ablation of the triazene containing polymers took place but cross-linking. The cross-linking reaction is explained by the addition of a radical formed during irradiation to an aromatic ring. In contrast the polycarbonates could be easily degraded at higher temperatures but the degree of degradation was strongly dependent on the nature of the acid.