气辅挤出成型中气垫膜层稳定性影响因素研究进展

Research Progress of the Influence Factors on the Stability of Gas Layer in Gas-Assisted Extrusion Molding

综述了聚合物气辅挤出成型过程中影响气垫膜层稳定性的一些因素:工艺参数(气体压力、气体温度、气体流量)、口模结构参数(口模有气辅段长度、环形缝隙)及气阀和挤出螺杆的开启顺序。要使气辅挤出过程中形成稳定的气垫膜层,气体的压力和温度与熔体的压力和温度应接近一致,并应先开启气阀,再打开螺杆进行挤出等。对未来的发展趋势进行了展望。

The research progress of some stability influence factors of gas layer in the gas-assisted extrusion molding process, such as technological parameters（gas pressure, temperature and flow rate）, die structure parameters（die length with gas-assisted and gas inlet size）and the turning sequence between gas valve and extrusion screw are summarized. For forming stable gas layer in the gas-assisted extrusion molding process, the gas pressure and temperature should be according with melt pressure and temperature, and extrusion screw turning followed with the gas valve opening when extruding.