Combined oligomeric light and heat stabilizers

摘要

A series of terpolymers containing structural units of hindered amine stabilizer (HAS), antioxidant of diphenylamine type and octadecyl alkyl chain has been prepared by radical oligomerization initiated by AIBN. Monomers bearing HAS represented acry- late, methacrylate or acrylamide of 2,2,6,6-tetramethyl and 1,2,2,6,6-penta-methylpiperidine respectively. Second monomer in ter- polymers was 4-amino-diphenylamine acrylamide or methacrylamide and the third one n-octadecyl acrylate. Molecular weights of oligomers lay in the region 4000--6500. The molar ratio of monomers in oligomers was approximately the same as in the mixtures of monomers before oligomerization (1:1:1). Oligomeric stabilizers were tested as photostabilizers in polyoctenamer and poly- propylene (PP) and as thermostabilizers in PP at 130℃. Stabilizing efficiency for all oligomeric stabilizers was roughly the same in photooxidation of PP. In the case of thermooxidation, the oligomer TMPA/DPA/ODA showed several times better efficiency than other oligomers.