郝明洋,王昌银,蒋团辉,张纯,何力,龚维

• 1:贵州师范大学材料与建筑工程学院
• 2:国家复合改性聚合物材料工程技术研究中心
• 3:贵州大学材料与冶金工程学院

摘要(Abstract)：

采用多官能度环氧化合物,通过官能团反应制备支化结构聚乳酸。通过动态剪切流变仪和差示扫描量热仪(DSC)分别考察了聚乳酸流变行为和结晶行为,结果表明改性之后聚乳酸的黏弹性显著提高,尤其是弹性响应,通过Cole-Cole图和Han图反映了支化结构的引入,此外,DSC表征结果表明改性后聚乳酸出现了明显的降温结晶峰,进一步映证了支化结构的存在。同时,利用型腔体积可控注塑发泡装备制备了聚乳酸发泡试样,结果表明支化结构的引入显著改善了聚乳酸的发泡行为。在泡孔生长动力学研究的基础上,将泡孔生长过程分为快速生长阶段和慢速生长应力松弛阶段,分析了聚合物熔体黏弹性对泡孔生长、稳定过程的影响,较高的黏弹性起到了抑制泡孔合并、恶化的作用。同时,改性之后聚乳酸结晶性能提高,有利于发泡过程中泡孔结构的稳定。

关键词(KeyWords)： 聚乳酸;支化;黏弹性;结晶行为;发泡;泡孔结构

Abstract:

Keywords:

基金项目(Foundation): 国家自然科学基金项目(21264004);; 贵州省科技厅重大专项(2012-6023);; 黔科合人才团队[2014]4006号

作者(Author): 郝明洋,王昌银,蒋团辉,张纯,何力,龚维

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