A Novel GPPS/cis‐SB Blend with High Performance

Abstract

AbstractSummary: GPPS/cis‐SB blends with high performance were prepared by adding 3–5 wt.‐% stereoregular butadiene‐styrene block copolymers (cis‐SB) with a high cis‐1,4 configuration of around 97% into general purpose polystyrene (GPPS). The micromorphology of the GPPS/cis‐SB blends was characterized by transmission electron microscopy (TEM). Mechanical properties including tensile and impact properties were studied and the fracture surfaces of tensile and impact test specimens were characterized by scanning electron microscopy (SEM). PB domains of 10–30 nm with a blurry interface were tethered by continuous PS domains. The fracture surface of the tensile test piece of GPPS was relatively smooth while the fractography of patch patterns separated by river patterns was formed when the tensile specimens of GPPS/cis‐SB blends were broken, which may be due to the nanometer‐scale rubber phases with high cis‐1,4 configuration and some partially crystalline PS segments in the cis‐SB block copolymer. It is found that GPPS could be greatly toughened by introduction of a small amount of cis‐SB and the tensile strength and elongation at break could also be increased.