STRESS-STRAIN BEHAVIOR AND IMPACT STRENGTH OF POLYSTYRENE POLYAMIDE-6BLENDS COMPATIBILIZED WITH POLY(STYRENE-G-ETHYLENE OXIDE)/

The mechanical properties of polystyrene/polyamide-6 (50/50 wt/wt) ble nds were improved by additions of small amounts of poly(styrene-g-ethy lene oxide) (SEO) during compounding by extrusion. Tensile testing of injection-molded samples revealed that the blends developed a yield po int after addition of 1 wt % SEO. The elongation at break increased by almost a factor of 6, and the impact strength increased by a factor o f 1.5 after adding 3 wt % SEO. Morphological analysis by electron micr oscopy showed that additions of SEO resulted in decreased domain sizes , and seemed to promote interfacial adhesion. The morphologies of the compatibilized blends also had a higher degree of anisotropy, as compa red with the uncompatibilized blend. (C) 1998 John Wiley & Sons, Inc.