Compatibilization Strategies for Recycling Applications of High Impact Polystyrene / Acrylonitrile Butadiene blends

Abstract

Plastic waste from electrical and electronic equipment (WEEE) is growing up exponentially fast during the last two decades, mainly due to short lifetime of technological products like cellphones or computers. This situation entailed an increase in the accumulation of specific plastic materials such Acrylonitrile–Butadiene–Styrene (ABS), High Impact Polystyrene (HIPS), Polycarbonate, among others. These plastics can be recycled by themselves but their separation by type is neither easy nor economically viable, then recycling them together as a blend is the most economically viable alternative. However, mechanical properties suffer a deterioration and to enhance phase adhesion and add value to this WEEE blend, an adequate compatibilization is needed. To choose a compatibilization route an accurate comprehension of blends behavior has to be done. In this work, a systematical study of the addition compatibilization of HIPS/ABS blends was performed. Besides results were focus to WEEE recycling, in order to comprehend this complex system, virgin base materials were used. Relative amount effect on self-compatibilization was analyzed by two different HIPS/ABS blends, one with major content of HIPS and other with major content of ABS. Also, two different copolymers were used as compatibilizer, Styrene–Acrylonitrile (SAN) and Styrene–Butadiene–Styrene and the concentrations chosen were 2 and 20 wt%. The best performance was achieved for blend with major content of ABS by using 2 % of SAN, obtaining a compatibilized blend with a general improvement of mechanical properties specially toughness in a 350 % and elongation in a 77 % respect to the physical blend.