紫外辐照引发的反应挤出过程对聚乳酸结构与性能的影响

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英文篇名：Effect of UV Induced Reactive Extrusion on Structure and Properties of Poly(Lactic Acid) 作者：陈昌乾 ; 何光建 ; 柯丁梦 ; 郑婷婷 ; 霍伟杰 ; 殷小春 英文作者：Changqian Chen;Guangjian He;Dingmeng Ke;Tingting Zheng;Weijie Huo;Xiaochun Yin;National Engineering Research Center of Novel Equipment for Polymer Processing,the Key Laboratory of Polymer Processing Engineering of Ministry of Education,South China University of Technology; 关键词：聚乳酸 ; 紫外辐照 ; 反应挤出 ; 结晶 英文关键词：poly(lactic acid);;UV irradiation;;reactive extrusion;;crystallization 中文刊名：GFZC 英文刊名：Polymer Materials Science & Engineering 机构：华南理工大学聚合物新型成型装备国家工程中心聚合物成型加工工程教育部重点实验室; 出版日期：2015-11-23 17:10 出版单位：高分子材料科学与工程 年：2015 期：v.31 基金：国家自然科学基金资助项目(21174044);; 华中科技大学材料成形与模具技术国家重点实验室开放课题(2012-P14) 语种：中文; 页：GFZC201511013 页数：5 CN：11 ISSN：51-1293/O6 分类号：64-68

摘要

采用紫外辐照手段对熔体态聚乳酸(PLA)在挤出过程中进行改性,研究了辐照反应过程中的喂料速度和交联剂含量对PLA的熔体指数、流变行为、结晶性能的影响。结果表明,不添加交联剂的条件下,紫外辐照后的PLA分子链发生断裂,黏度降低,结晶能力减弱;加入多官能团助剂三羟甲基丙烷三丙烯酸酯(TMPTA)后,紫外辐照PLA的弹性模量和复数黏度在低频区有明显提高,表明PLA形成了支化结构,抑制了PLA的降解过程,熔体流动性下降。支化PLA的结晶速率增大,结晶度提高。
        UV irradiation was adopted to modify molten poly(lactic acid)(PLA)during extrusion process.The effects of the feeding speed and the content of crossing-link agent on melt flow rate,rheological behavior,crystallization and mechanical properties of PLA were studied.The results show that chain scission of PLA occurs when exposed to UV irradiation during extrusion.The MFR of PLA increases along with the tensile strength but crystallization ability declines.While adding the crossing-link agent TMPTA into PLA,MFR decreases confirming that the chain scission reaction of PLA is depressed.The viscosity of PLA containing TMPTA increases after irradiation.Dynamic rheological analysis shows that the elastic modulus and complex viscosity increase apparently at low frequency,which means that the long-chain branched structure is formed.Non-isothermal crystallization rate and crystallinity of long chain branched PLA are improved.

引文

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