塑料微管气辅挤出成型实验与机理分析  

Experiment and Mechanism Analysis of Gas-assisted Extrusion Forming for Plastic Micro-tube

作　　者：任重[1,2] 黄兴元[3] 柳和生 REN Zhong;HUANG Xingyuan;LIU Hesheng(Key Laboratory of Optic-electronic and Communication,Jiangxi Science and Technology Normal University,Nanchang 330038,China;Key Laboratory of Optic-electronic Detection and Information Processing of Nanchang City,Jiangxi Science and Technology Normal University,Nanchang 330038,China;College of Mechanical and Electric Engineering,Nanchang University,Nanchang 330031,China;School of Chemical Biology and Materials Science,East China University of Technology,Nanchang 330013,China)

机构地区：[1]江西科技师范大学光电子与通信重点实验室,南昌330038 [2]江西科技师范大学光电检测与信息处理重点实验室,南昌330038 [3]南昌大学机电工程学院,南昌330031 [4]东华理工大学化学生物与材料科学学院,南昌330013

出　　处：《材料导报》2020年第20期20193-20198,共6页Materials Reports

基　　金：国家自然科学基金(51763011);江西省自然科学基金杰出青年项目(2018ACB21006);江西省自然科学基金面上项目(20192BAB206016);江西省创新杰出青年人才(20192BCBL23015);南昌市光电检测与信息处理重点实验室项目(2019-NCZDSY-008)。

摘　　要：为了解决传统塑料微管挤出产生的挤出胀大、熔体破裂和挤出变形等问题,本工作采用内外双层气体辅助技术开展了塑料微管气辅挤出实验,并将其与传统挤出实验结果进行了对比。为了进一步揭示气辅技术可以消除传统挤出产生上述问题的机理,利用有限元方法对塑料微管气辅挤出和传统挤出进行了数值模拟和对比分析。实验结果表明,气辅技术不仅很好地克服了挤出胀大和挤出变形,而且使得挤出的塑料微管表面平整度、光泽度和透明度均有很大提高。数值结果表明,气辅技术较好地减小了熔体在口模流道内尤其是口模出口处的压力、剪切和法向应力差分布,使得塑料微管熔体在口模内的流动从黏着无滑移剪切流动转变为完全滑移无黏着流动,并且在口模出口处流速分布均匀且无突变和径向流速,从而较好地克服了塑料微管传统挤出方式产生的问题。In order to solve the extrudate swell,extrusion fracture and extrusion distortion problems generated by the traditional extrusion of plastic micro-tubes,the inner and outer layers of gas-assisted technique was applied into the extrusion forming of plastic micro-tubes in this work.The gas-assisted extrusion experiments of plastic micro-tubes were carried out.The experimental results were compared with that of the traditional extrusion.To further ascertain the reason that the gas-assisted method can overcome the problems produced by traditional method,the numerical simulations of traditional method and gas-assisted extrusion method were performed and compared with each other.Experimental results show that the gas-assisted technique not only overcomes the extrudate swell of traditional extrusion of plastic micro-tubes,but also improves the glossiness and transparency on the surface of extruded plastic micro-tubes.Numerical results show that by using the gas-assisted method,the pressure,shear and normal stress difference distributions of melts in the channel of die are greatly eliminated,especially at the outlet of die,which results in the melt’s sticky and no-slip shear flow of traditional extrusion is changed into the full slip and no sticky flow.Moreover,at the outlet of die,the flow velocity distributions of melt are uniformed even without sudden change and radial flow velocity.Therefore,the extrusion problems of plastic micro-tubes are well solved by means of the gas-assisted technique.

关 键 词：塑料微管 挤出成型 气辅技术 有限元分析 

分 类 号：TQ320.663[化学工程—合成树脂塑料工业]