Recycling Of ABS Plastic From The Housing Of Waste Electrical And Electronic Equipment

In recent years, the output of electrical and electronic equipment increases year by year,and the consumption of housing plastics of electrical and electronic equipment is alsoincreases significantly. When electrical and electronic equipment is discarded, a large amountof waste electrical and electronic equipment (WEEE) plastics will be generated, which cancause serious pollution to the environment. So more and more attentions are paid to therecycling of WEEE plastics. ABS plastic takes a great proportion in WEEE plastics, and thispaper deeply studied the aging mechanism of ABS plastic which is used for the housing ofelectrical and electronic equipment, and then, thinking from the perspective ofmolecular-chain repair, chain extenders were used to recover the properties of recycled ABS(rABS).This paper studied the differences in the performance between rABS and virgin ABS(vABS), and then2,2′-(1,3phenylene)-bis (PBO) and polyfunctional epoxy resin (EP) wereadopted as chain extender to make rABS chain extended. The effect of content of each chainextender on molecular weight, mechanical properties, thermal properties, morphology of thefracture surface, dynamic mechanical properties and dynamic rheological properties of rABSwere studied.The results showed that the aging of ABS mainly occurred in1,4-butadiene segments. Asa result, the molecular chains broke, and obvious boundaries appeared between phaseinterface, and the number of rubber phase (PB) particles that dissociated from matrix (SAN)increased, and the impact fracture surface became smooth. These results eventually led to the loss on mechanical properties. When PBO and EP were added in rABS respectively, themolecular weight of rABS showed a substantial increase and the mechanical properties alsoincreased and the optimum comprehensive mechanical properties were obtained when thecontent of PBO and EP was0.7wt%respectively; the phase interface of rABS becameblurred, and the number of PB particles that dissociated from matrix (SAN) decreased and theimpact fracture surface became uneven, which indicated that the combining power betweenPB and SAN were enhanced; both the storage modulus and loss modulus of rABS increased,which showed the increase of viscoelasticity of rABS.In this paper, starting from the perspective of molecular-chain repair, we improved theperformance of rABS by adding low-cost chain extenders, and the chain-extension reactionwas performed in double screw extruder that has a simple process flow. These have importantsignificance for both economy and environment protection.