高频电场与正应力场协同作用下聚合物的热响应特性  

Study on Thermal-Response Characteristic of Polymer Materials to Synergism of High-Frequency Electric Field and Normal Stress Field

作　　者：杨智韬[1] 童益彰 徐文华[1] 殷小春[1] 张桂珍[1] 瞿金平[1] YANG Zhitao;TONG Yizhang;XU Wenhua;YIN Xiaochun;ZHANG Guizhen;QU Jinping(National Engineering Research Center of Novel Equipment for Polymer Processing//Key LaboEngineering of the Ministry of Education, South China University of Technology,Guangzhou 510640, Guangdong,China)

机构地区：[1]华南理工大学聚合物新型成型装备国家工程研究中心∥聚合物成型加工工程教育部重点实验室,广东广州510640

出　　处：《华南理工大学学报（自然科学版）》2018年第2期131-139,共9页Journal of South China University of Technology(Natural Science Edition)

基　　金：国家自然科学基金青年基金资助项目(51403068;51505153);华南理工大学中央高校基本科研业务费专项资金资助项目(2017ZD013)~~

摘　　要：目前高分子材料成型方法都采用高温塑化、低温成型的成型机理进行加工.这一过程消耗了大量的能量,并造成聚合物及其添加剂的热降解,降低了塑料的性能和可回收性.因此,文中在聚合物热压成型加工中引入高频电场,使物料在正应力和高频电场协同作用下实现低温塑化,研究物料在高频电场中发生热响应的压力、温度依赖性,以及在临界塑化温度点下制备的聚合物片材的力学性能,建立合理的温升模型.研究表明:材料极性越强,其介电损耗越高,物料吸热能力越强;极性材料和非结晶性聚合物吸热量随成型压力的增大而增大,而非极性的结晶性聚合物吸热量存在最佳吸热压力点;均聚物具有最佳吸热温度点,而多相的共聚物吸热量随加工温度呈指数增长;施加高频电场试样的拉伸性能显著提升,证实了协同低温塑化行为的存在.Currently,polymer materials are processed by high temperature plasticizing and low temperature molding. These processing needs to spend a lot of energy and causes the degradation of polymers and additives,reducing product performances and recovery. Therefore,this article introduces high-frequency electric field into hotpressing process of polymers,making the materials plasticize in synergism of normal stress field and high-frequency electric field at low temperature. The dependence of pressure and temperature on thermal-response of polymer materials to the high frequency electric field,as well as the mechanical properties of pure polymer plates which are prepared at critical plasticizing temperature point,is studied in depth; a model of temperature-rising is also reasonably established. The results show that the stronger polarity of polymer materials,the higher dielectric loss and absorbed heat will be; the absorbed heat of polar materials and amorphous polymer are positively related to the processing pressure,while the absorbed heat of non-polar crystalline materials have the best pressure point in which materials absorb the maximal heat. Homo-polymer have the best temperature points for heat absorption,while the absorbed heat of copolymer exponentially increase with the processing temperature rising. The tensile properties of specimens with high-frequency electric field improved significantly when compared to the specimens without high-frequency electric field,proving the existence of plasticizing behavior at low temperature under the synergism of normal stress field and high-frequency electric field.

关 键 词：高频电场 正应力 温升模型 压力依赖性 温度依赖性 低温塑化 

分 类 号：TQ320.52[化学工程—合成树脂塑料工业]