PLA/Lyocell纤维复合材料结构与性能研究

Study on Structure and Properties of PLA/Lyocell Fiber Composites

以聚乳酸(PLA)为基体,新型纤维素纤维Lyocell纤维为增强材料,通过熔融共混及注塑成型制备了PLA/Lyocell纤维可生物降解复合材料,并采用扫描电镜(SEM)、力学性能测试、差示扫描量热法(DSC)和维卡软化温度测试等手段,探讨了Lyocell纤维含量对复合材料结构和性能的影响。结果表明:随着Lyocell纤维含量的增加,PLA/Lyocell纤维复合材料的结晶度、弯曲模量和维卡软化温度均随之提高,而拉伸强度和冲击强度则呈现先上升后下降的趋势。其中当Lyocell纤维含量达到6%时,其在复合材料中的分布较为均匀,所对应复合材料的力学性能相对较好,其拉伸强度、缺口冲击强度和弯曲模量比纯PLA分别提高了15.3%、12.3%和13.0%。

Using a novel cellulose fiber（Lyocell fiber） as the reinforcing material,the biodegradable polylactic acid（PLA）/Lyocell fiber composites were prepared by melting blend and injection molding method.The effect of Lyocell fiber content on the structure and properties of the composites were investigated by means of scanning electron microscope（SEM）,mechanical property test,differential scanning calorimetry（DSC） and Vicat softening temperature test.The results show that with the increasing of the amount of Lyocell fiber,the crystallinity,flexural modulus and the Vicat softening temperature of the PLA/Lyocell fiber composites increase,while the tensile strength and notched impact strength increase firstly and then decrease.When the content of Lyocell fiber is 6%,Lyocell fiber could be distributed uniformly in the composite.The composite has better mechanical properties than those of pure PLA material,and the tensile strength,notched impact strength and flexural modulus increase by 15.3 %,12.3% and 13.0%,respectively.