Access to new polymeric-hindered amine stabilisers from oligomeric terpene resins

Abstract

This paper reports on the use of terpene resins as precursors for synthesis of oligomeric stabilisers by photochemical grafting of acrylate monomer with suitable substituents as sterically hindered amine. Poly α and poly β pinenes react with singlet oxygen to produce macromolecular hydroperoxides. Then, the reactivity of 1,2,2,6,6-pentamethyl-4-piperidyl acrylate (PMPA) is sufficient to afford grafting by photochemical decomposition of ROOH at λ>300 nm at 35°C. Hence, photo- and thermo-stability of the obtained polymeric hindered amine stabilisers are checked. Finaly, light and thermal stabilising efficiency of grafted terpenic resins are tested for different dienic polymers. From our results, all terpene additives prepared dramatically increase the lifetime (both in photo- and thermal-ageing) of parent polymers and dienic elastomers as polyisoprene and polyoctenamer which are well-known to be highly sensitive to oxidation.