Material recycling of Acrylonitrile Butadiene Styrene (ABS) from toy waste using density separation and safer solvents

Abstract

Toy waste is an issue for municipal plastic recycling programs. In particular, toy waste typically is composed of different plastics and some metals. Separation of different parts of toy waste is necessary before recycling. In this study, a dissolution-precipitation process coupled with density separation was developed to extract acrylonitrile butadiene styrene (ABS) from toy waste using safer solvents and antisolvents. The polymer solubility of ABS was measured using Hansen solubility parameters, which were then used to down-select proper safer solvents and antisolvents. The acetone-water with a volumetric ratio of 3:1 was determined to be the most effective safer solvents and antisolvents for extracting 81 wt.% of ABS at room temperature. The recovered ABS has comparable mechanical behavior to the feedstock material with a similar glass transition temperature and molecular weight distribution. Compared to producing virgin ABS material, the dissolution-precipitation process reduces embodied energy by 58%.