Compatibilizing and toughening blends of recycled acrylonitrile-butadiene-styrene/recycled high impact polystyrene blends via styrene-butadiene-glycidyl methacrylate terpolymer

To increase the effectiveness of recovered acrylonitrile-butadiene-styrene (rABS) and recycled high impact polystyrene (rHIPS), styrene-butadiene-glycidyl methacrylate (SBG) was incorporated to the rABS/rHIPS system by melt blending for the first time. Multiple epoxy groups in SBG can combine with the butadiene ageing groups in rABS/rHIPS to generate ester groups, repairing the broken molecular chains, improving the compatibility between the two phases, and enhancing the mechanical properties of the blends. The findings demonstrated that adding SBG greatly increased the blends' molecular weight, impact strength, tensile strength, flexural strength, storage modulus, loss modulus, and complex viscosity. When SBG content was 8 wt%, the notch impact strength of the blends reached 8.84 kJ/m2, which was 108% higher than that of rABS/rHIPS. In addition, the interface between polybutadiene (PB) phase and styrene-acrylonitrile copolymer (SAN) phase became more blurred, and the compatibility of the two phases was improved, which enabled the high-value recovery of rABS/rHIPS.