超高相对分子质量聚乙烯管材新型连续挤出成型技术

超高相对分子质量聚乙烯（PE-UHMW）管材连续挤出成型法有压制-烧结、柱塞推压、单螺杆挤出、双螺杆挤出和柱塞冲压挤出等几种，其中柱塞冲压挤出成型法是新开发的一种PE-UHMW管材连续挤出成型技术，该技术的突出优点表现在：能加工任意相对分子质量的PE-UHMW树脂，加工能力强；能实现连续挤出，生产效率不低于单螺杆挤出法，而制品的表面质量、力学性能（如耐磨性）则优于单螺杆挤出法；完全正位移输送机理，温度控制简单可靠（控温段只有三个），因此加工过程中的降解程度较小，能很好地保持原料固有的优良性能；主机结构简单，能耗低（约为螺杆挤出法的30％～50％），生产线造价便宜。另外，采用该技术还能挤出高质量的聚四氟乙烯（PTVE）和过氧化物交联聚乙烯（PEX-a）制品。

New Continuous Extrusion Technology for Ultra-high Molecular Weight Polyethylene Pipes

Punching plunger extrusion is a novel continuous extrusion molding technology, which provided higher processing capacity, better appearance and quality of the extrudate, compared with single-screw extrusion. A special facility was designed for the processing of PE-UHMW, PTFE, and peroxide-crosslinked polyethylene(PEX-a)with low degradation and high property retaining because of its absolute positive displacement transportation mechanism and reliable temperature control. Owing to the simple structure of the machinery, a low energy consumption (30 %-50 % that of screw extruder) was achieved. Otherwise, the novel processing method is suitable for the pipes of polytetrafluoroethylene (PTFE)and PEX-a.