原纤化Lyocell纤维/聚乳酸复合材料的结构与性能

采用均质分散法制备原纤化Lyocell纤维,探讨了不同初始纤维长度对Lyocell纤维原纤化程度的影响,在此基础上,进一步通过熔融共混和注塑成型制备原纤化Lyocell/聚乳酸(PLA)复合材料,探讨了初始纤维长度对原纤化Lyocell/PLA复合材料结构与性能的影响。结果表明,相同处理条件下,纤维初始长度越长,Lyocell纤维原纤化程度越低。Lyocell纤维原纤化能改善纤维与基体的界面结合,从而进一步提高复合材料的力学性能。初始纤维长度对原纤化Lyocell/PLA复合材料的拉伸性能无显著影响,而初始长度为4 mm的原纤化Lyocell/PLA复合材料的缺口冲击强度最大,比未原纤化复合材料提高19.0%。此外,Lyocell原纤化后还可进一步提高复合材料的维卡软化温度,当纤维初始长度为10 mm时,原纤化Lyocell/PLA复合材料的维卡软化温度最高,达到161.4℃。

Structure and Properties of Fibrillated Lyocell Fiber/ Polylactic Acid Composite

The homogenization method was used to prepare the fibrillated Lyocell fiber,and the effect of different initial fiber lengths on the fibrillation degree of Lyocell fiber was studied.On this basis,the fibrillated Lyocell/polylactic acid(PLA)composites were prepared by melt blending and injection molding,and the effect of initial fiber length on the structure and properties of fibrillated Lyocell/PLA composites were investigated.The results show that the longer the initial fiber length is,the lower the fibrillation degree of the fiber under the same treatment conditions is.The fibrillation of Lyocell fibers improves the interfacial bonding between fibers and matrix,thereby further increases the mechanical properties of composites.The initial fiber length has no significant effect on the tensile properties of fibrillated Lyocell/PLA composites,whereas the fibrillated Lyocell/PLA composite with the initial length of 4 mm shows the highest notch impact strength,which is 19.0%higher than that of the non-fibrillated composite.In addition,the Vicat softening temperature of the Lyocell/PLA composite can be further increased by the fibrillation of Lyocell fiber.The fibrillated Lyocell/PLA composite with the initial fiber length of 10 mm shows the highest Vicat softening temperature of 161.4℃.