After crushing twice and screening,polypropylene components in end-of-life vehicles were two-stage separated and purified by high-voltage corona-electrostatic separation technique,and the separation technique was optimized.The purified polypropylene materials were modified by the modifier composed of 50wt% 8303K polypropylene,30wt% 7467 polyolefin elastomer,3.5wt% KH-560 coupling agent,3.5wt% polyethylene wax, etc.,and were inj ection molded.The mechanical properties and physical and chemical properties of the materials before and after modification were studied.The results show that after crushing and screening,the materials with particle size below 1.25 mm mainly consisted of rod-sheet-like polypropylene and contained few glass fibers,plastic powders and peeled copper wires.In the process of separation and purification,with the rotation speed of the first roller of 114 r.min-1 and the second roller of 33 r.min-1 ,about 78wt% polypropylene materials were obtained,and over 13wt% metallic materials were separated.The mechanical properties of the purified polypropylene were improved after modification,meeting the requirements of automobile manufacturers.%报废汽车聚丙烯零部件经二次破碎、筛分后,采用高压电晕-静电分选技术进行二级分选提纯,对分选提纯工艺进行了优化;用由50%(质量分数,下同)8303K聚丙烯、30%7467聚烯烃弹性体、3.5%KH-560硅烷偶联剂、3.5%聚乙烯蜡等组成的改性剂对提纯后的聚丙烯物料进行共混改性并注塑成型,研究了改性前后物料的力学及理化性能.结果表明:破碎筛分后,粒径在1.25 mm以下的物料以长条片状聚丙烯为主,混有少量玻璃纤维、塑料粉以及已解离铜丝;分选提纯时第一辊转速为114 r.min-1,第二辊转速为33 r.min-1,得到质量分数约78%的聚丙烯,而质量分数超过13%的金属被分选出;提纯得到的聚丙烯经改性后,其力学性能提高,满足汽车生产厂家的使用要求.
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