摘要
聚乳酸/天然橡胶(PLA/NR)共混物通过双螺杆挤出机进行共混造粒,采用常规注塑成型得到的未发泡样条表观颜色均一。采用扫描电镜观察样条的内部结构,结果显示,PLA/NR共混物呈海-岛结构,共混物中NR颗粒分散相呈不均匀分散。拉伸测试结果显示,纯PLA的断裂伸长率低,呈脆性断裂,共混物的力学性能比纯PLA的差。以超临界CO_2流体作为发泡剂,采用微孔注塑发泡技术制备了纯PLA、PLA/NR-5%和PLA/NR-10%共混物发泡样品。扫描电镜观察显示,纯PLA发泡样的泡孔结构均匀,但是PLA/NR共混物的泡孔结构均一性较差,出现了微米级的空洞,由于PLA与NR之间较弱的界面结合力,使共混物发泡样的拉伸性能变差。
Polylactide/natural rubber （PLA/NR） blends were extruded into pellets by a twin-screw extruder. The samples without foams obtained from conventional injection molding showed uniform color. The inner structure of the samples was observed by scanning electron microscope （SEM）. The results showed that PLA/NR blends had a sea-island phase structure, but the dispersed NR phase was not uniform in particle sizes. The tensile properties showed that pure PLA was brittle fractured with a low elongation at break, and the blends were poorer than pure PLA. Foamed PLA, PLA/NR-5% and PLA/NR-10% tensile samples were prepared by microeellular injection foaming technique using CO2 as the blowing agent. SEM results showed that foamed PLA was presented with uniform cells, however, the cells of the foamed PLA/NR blends were in millimeter size and the tensile properties were even poorer due to the weak interfacial adhesion between PLA and NR.
作者
张春梅
翟天亮
曹恩忠
刘海腾
谢黎
黄保连
ZHANG Chunmei;ZHAI Tianliang;CAO Enzhong;LIU Haiteng;XIE Li;HUANG Baolian(College of Chemistry and Materials Engineering, Guiyang University, Guiyang, Guizhou 550005, China;Guizhou Building Material Quality Supervision Testing Center,Guiyang,Guizhou 550000, China)
出处
《塑料》
CAS
CSCD
北大核心
2018年第2期50-52,74,共4页
Plastics
基金
贵州省普通高等学校科技拔尖人才支持计划(黔教合KY字[2016]089)
国家质量监督检验检疫总局科技计划项目(2016QK041)
关键词
超临界CO2
微孔发泡
聚乳酸
天然橡胶
多孔材料
supercritical CO2
mierocellular foaming
polylactide
natural rubber
porous material
