Influence of core-shell particles structure on the morphology and brittle-ductile transition of PBT/ABS-g-GMA blends

The performance of glycidyl methacrylate (GMA) functionalized acrylonitrile-butadiene-styrene coreshell impact modifiers (R-ABS) with varied GMA content, crosslinking degree of rubber phase, coreshell ratio, and initiator type in toughening of poly(butylene terephthalate) (PBT) was investigated. Results show that 1 wt% GMA is sufficient to induce a pronounced improvement of the impact strength of PBT and too much GMA induces the crosslinking of R-ABS. Divinylbenzene improves the crosslinking degree of polybutadiene and decreases its cavitation ability. The brittle-ductile transition shifts to higher R-ABS content. When the coreshell ratio of R-ABS is beyond 70/30, compatibilization reaction is not sufficient to retard the agglomeration of coreshell particles. R-ABS particles with the coreshell ratio between 50/50 and 60/40 are suitable. Initiator type can influence the internal structure of R-ABS. For R-ABS prepared with azobisisobutyronitrile (AIBN) as initiator, big subinclusion structure decreases its toughening ability. R-ABS prepared with redox initiator shows better toughening behavior. POLYM. COMPOS., 2013. (c) 2012 Society of Plastics Engineers