Effects of Reprocessing on Acrylonitrile-Butadiene-Styrene and Additives

Acrylonitrile-butadiene-styrene (ABS) is one of the most extensively used engineering polymers. It is necessary to study the recycling of ABS because of environmental, economic and energy reasons. In this study, an ABS resin was processed using a torque rheometer at different temperatures and for different numbers of cycles. Pyrolysis gas chromatography mass spectrometry (Py-GC/MS) was used to study the effects of the processing parameters on additives. Fourier transform infrared spectroscopy, hydrogen nuclear magnetic resonance spectroscopy, and gel permeation chromatography (GPC) were used to analyse the structural changes in the resin. GPC results showed that after processing at 290 degrees C using the torque rheometer, large size soluble polymeric components increased. The increase in the large size soluble polymeric components after processing at 290 degrees C was probably related to the crosslinking reactions in the grafted polybutadiene. Furthermore, chemical analysis of the ABS resin samples after multiple extrusion cycles in a twin-screw extruder indicated that reprocessing considerably affected the ABS resin.