木粉/聚乳酸可降解复合材料性能研究

Study on property of polylactic acid/wood flour composites

用生物可降解材料聚乳酸(PLA)和桉木粉(WF)为原料,制备木粉/聚乳酸(WF/PLA)复合材料,为实现木塑复合材料完全生物降解提供新思路。采用傅立叶变换红外光谱仪(FT-IR)、扫描电子显微镜(SEM)、同步热分析仪(TG/DSC)及电子万能试验机研究了改性前后木粉的红外结构,WF/PLA复合材料的微观形貌、热性能和结晶性能以及其力学性能。结果表明,偶联剂KH-570的烷基结构成功接枝到了木粉表面;改性后的木粉在聚乳酸基体中分散均匀;木粉的添加有利于WF/PLA复合材料异相成核结晶和热稳定性的提高;木粉对PLA起到增强作用,当木粉填量为50%(质量分数)时,WF/PLA复合材料的拉伸强度最大,值为29.9MPa,比纯PLA提高了10MPa,木粉填量为30%(质量分数)时,WF/PLA复合材料的弯曲强度最大,值为43.2MPa,比纯PLA提高了7.3MPa。

Biodegradable materials,polylactic acid and old eucalyptus wood powder are used as raw material to prepare polylactic acid/wood flour composite （WF/PLA）,which provide thought for wood plastic composite completely degradation.FT-IR spectrophotometer,scanning electron microscope and simultaneous thermal ana-lyzer were employed to research the interfacial connection property,thermal properties and crystallization prop-erty,together with mechanical property was studied of WF/PLA.The results showed that：alkyl of KH-570 was grafted to the WF surface;the heterogeneous nucleation crystallization and thermostability improved with the increase of filling WF.When content of wood flour was 50%,the maximum tensile strength of the compos-ite was 29.9 MPa,which was 10 MPa higher than pure polylactic acid;when content of wood flour was 30%, the maximum bending strength of the composite was 43.2 MPa,which was 7.3 MPa higher than pure polylactic acid.