挤出循环对聚丙烯/竹粉复合材料力学及发泡性能的影响  

Effects of multiple extrusions on mechanical and foaming properties of polypropylene/bamboo fiber composites

作　　者：李琪微 王翠翠 郑海军 陈季荷 王戈 程海涛 LI Qiwei;WANG Cuicui;ZHENG Haijun;CHEN Jihe;WANG Ge;CHENG Haitao(International Center for Bamboo and Rattan,Beijing 100102,China)

机构地区：[1]国际竹藤中心,北京100102

出　　处：《中国塑料》2022年第2期56-60,共5页China Plastics

基　　金：国际竹藤中心基本科研业务费专项资金(1632021002);林业和草原科技成果国家级推广项目(2020133151)。

摘　　要：通过双螺杆挤出机对30%(质量分数,下同)竹粉增强聚丙烯(PP/BP)复合材料进行循环加工,研究了挤出循环次数对PP/BP复合材料流变性能、力学性能和发泡性能的影响。结果表明,随着挤出循环次数的增加,PP/BP复合材料的表观黏度(η)先升高后降低,力学性能先增强后减弱,经第6次挤出循环后,其η、弹性模量和弯曲模量比1次挤出分别降低了23.75%、17.08%和31.18%。随着挤出循环次数的增加,PP/BP复合材料泡孔尺寸逐渐均匀,纤维由长纤维状转为短棒状和颗粒状,纤维分散更均匀,界面结合更紧密。The polypropylene(PP)-based composite reinforced with 30 wt%bamboo powders(BP)was prepared through six-cycle extrusion using a twin-screw extruder.The effect of recycle times on the rheological,mechanical,and foaming properties of the BP/PP composite was investigated.The results indicated that with an increase in the cycle number of extrusion,the apparent viscosity of the composite increased at first and then tended to decrease,but its mechanical pro-perties showed an opposite trend.The apparent viscosity decreased by 23.75%after extrusion for six time.Compared to the original composite,the composite extruded six times showed a decrease in tensile strength by 17.08%and in strength by 31.18%.With an increase in the cycle number of extrusion,the composite showed a change in cell distribution from uneven to uniform,and its cell size became uniform gradually.Moreover,the distribution of BP tended to be uniform in the cell wall,and BP became short rods and granules instead of long fibers.

关 键 词：挤出循环 竹粉 复合材料 流变性能 力学性能 发泡性能 

分 类 号：TQ325.14[化学工程—合成树脂塑料工业]