Rubber toughening of an amorphous polyamide by functionalized SEBS copolymers:morphology and Izod impact behavior

摘要

Rubber toughening of an amorphous polyamide (Zytel 330) using combinations of triblock copolymers of the type SEBS and a maleic anhydride functionalized version,SEBS-g-MA,was investigated and the results compared with those of nylon 6 and nylon 66.The effects of rubber content and the type of extruder on the morphology,Izod impact behavior and the ductile-brittle transition temperature were explored.The shape and sizes of the rubber particles in blends with this amorphous polyamide were found to be more similar to those in nylon 6 than in nylon 66 blends.The twin screw extruder produced smaller particles with a more narrow distribution of sizes than the single screw extruder.Higher rubber contents generally yielded tougher blends;there is a critical rubber particle size above which the ternary blends are brittle at 20 wt% total rubber.The ductile-to-brittle temperature was found to decrease with increased rubber content and decreased rubber particle size.In general,the trends for this amorphous polyamide are rather similar to those reported earlier for semi-crystalline nylon 6 and nylon 66.