Polymer blends of polyamide-6 and poly(phenylene oxide) compatibilized by styrene-co-glycidyl methacrylate

Incompatible polymer blends between polyamide-6 (PA6) and poly(phenylene oxide) (PPO) have been compatibilized in situ by the styrene-glycidyl methacrylate (SG) reactive copolymers. The epoxy functional groups in SG copolymers can react with the PA6 amine and carboxylic endgroups at interface to form various SG-g-PA6 copolymers. These in situ-formed grafted copolymers tend to anchor along interface to function as compatibilizer of the blends. The styrene and the SG segments of the grafted copolymers are miscible (or near miscible) with PPO; whereas the PA6 segments are structurally identical with PA6 phase. The compatibilized blend, depending on quantity of the compatibilizer addition and the glycidyl methacrylate (GMA) content in the SG copolymer, results in smaller phase domain, higher viscosity, and improved mechanical properties. About 5% GMA is the optimum content in SG copolymer that produces the best compatibilization of the blends. This study demonstrates that SG reactive copolymers can be used effectively in compatibilizing polymer blends of PA6 and PPO. (C) 1996 John Wiley & Sons, Inc.