Reactive compatibilization of ABS/Nylon 6,6 blends: Effects of reactive group concentration and blending sequence

Abstract

Styrene-acrylonitrile-glycidyl methacrylate (SAG) copolymers with various glycidyl methacrylate (GMA) contents have been used to compatibilize the incompatible blends of acrylonitrile-butadiene-styrene (ABS) and nylon 6,6 (N66) by varying the blending sequences. When the epoxy group of SAG copolymer makes contact and reacts with the amine endgroup of N66, the resultant grafted products, SAG-g-N66, tend to reside at interface and act as compatibilizers of the blends. For a SAG copolymer with lower GMA content (SG2), a better compatibilized blend is achieved by sequential blending of the SAG2 with N66 then with ABS. When a higher GMA content SAG (SAG 10) is employed, on the contrary, a better compatibilized blend is obtained by preblending SAG10 with ABS then with N66. A grafted SAG-g-N66 molecule is considered as an effective compatibilizer when it anchors along the interface with the ungrafted SAG, or the SA segments, penetrating into the ABS phase while the branched N66 chains protruding into the N66 phase. The conventional one-step three-component blending usually results in less compatibilized blend than the properly selected sequential blending. The trend of mechanical properties observed closely match the compatibility of the blend in terms of domain size. However, the overall improvement of the resultant mechanical properties of the compatibilized blend over the uncompatibilized one is not substantial.