Synthesis of novel bifunctional polymer stabilizers—A combination of HALS and UV absorber

The synthesis of new stabilizer type compounds (a combination between 2,2,6,6-tetramethylpiperidine and 2-hydroxyphenylbenzotriazole in one molecule) is reported. Six combined polymerizable stabilizers, containing one or two allyl groups, as well as two unsaturated allyloxy-[1,3,5]triazinyl-2,2,6,6-tetramethylpiperidines and three unsaturated allyloxy-[1,3,5]triazinyl-2-hydroxyphenylbenzotriazoles as individual stabilizers were synthesized. Their copolymers and the corresponding terpolymers of the individual stabilizers with methyl methacrylate were obtained. Chemical bonding of the stabilizers in the polymer was confirmed spectrophotometrically. The influence of these additives on the photostability of the copolymers was studied. The participation of the combined stabilizers in the polymerization did not affect considerably the molecular weight and the polydispersity of the copolymers. A significant stabilizing effect against photodegradation was determined. Polymerizable stabilizers, containing two different unsaturated groups in their molecule, showed considerably higher photostabilizing efficiency towards the compounds containing only one allyl group.