Abstract: PEB-g-MAN, synthesized by suspension grafting copolymerization of methyl methacrylate and acrylonitrile onto poly(ethene-co-1-butene) (PEB), was prepared to toughen styrene-acrylonitrile copolymer(SAN). Thermal performance and aging properties of the PEB-g-MAN/SAN blends were studied using DMA, TG/DTG, accelerated weathering aging, and thermal oxidative aging tests. DMA analysis showed that the differences of glass transition temperature (Tg) between PEB phrase and SAN phrase in PEB-g-MAN/SAN blends were apparently less than those between PEB elastomer and SAN resin, indicating PEB-g-MAN and SAN were partially compatible. TG/DTG results revealed that PEB-g-MAN/SAN blends performed better thermal stability than SAN resin. The aging test demonstrated the weatherability and yellowing resistance properties of PEB-g-MAN/SAN blends were much better than those of ABS. After thermal oxidation aging test, the retention of notched impact strength of PEB-g-MAN/SAN blends was superior to ABS, while the tensile strength and the flexural strength were slightly less than ABS.

Key words: poly(ethene-co-1-butene), methyl methacrylate, acrylonitrile, styrene-acrylonitrile copolymer, suspension polymerization, thermal stability, aging property