Zhang Lei, Lv Shanshan, Sun Ce, Wan Lu, Tan Haiyan, Zhang Yanhua
College of Materials Science and Engineering, Key Laboratory of Bio-based Material Science and Technology, Northeast Forestry University, Harbin 150040, China.
Polymers (Basel). 2017 Nov 9;9(11):591. doi: 10.3390/polym9110591.
Maleic anhydride (MAH) was used as the grafting monomer, which was prepared by melt grafting reaction in the twin screw extruder with dicumyl peroxide (DCP) as the initiator, polylactic acid grafted with maleic anhydride (MAH-g-PLA) was successfully prepared as the interface compatibilizer. The PLA/Wood fiber/MAH-g-PLA composites were prepared by melt blending and injection molding with different proportions of compatibilizer added, within which PLA was for the matrix phase and wood fiber was for the reinforcing phase. The crystallinity, microstructure, thermal stability and dynamic thermomechanical property of the composites were studied by X-ray diffraction (XRD), scanning electron microscope (SEM), thermo gravimetric analyzer (TGA) and dynamic mechanical thermal analysis (DMA). Furthermore, the mechanical and water absorption properties of the composites were also characterized. Results showed that the tensile strength and flexural strength of the composites attained the highest at 30% MAH-g-PLA added, where the crystallinity of the composites also showed the highest value. DMA results showed that the addition of MAH-g-PLA interfacial compatibilizer increased the loss modulus of the composites and improved the toughness. Scanning electron microscopy (SEM) showed that when the MAH-g-PLA was used, wood fiber is well dispersed in the PLA matrix phase, and that the interfacial compatibility between the matrix and the enhanced phase was improved. Therefore, the addition of MAH-g-PLA could improve the interfacial compatibility of PLA/Wood fiber composites and improve the mechanical properties of the composites.
以马来酸酐（MAH）为接枝单体，在双螺杆挤出机中以过氧化二异丙苯（DCP）为引发剂通过熔融接枝反应制备了马来酸酐接枝聚乳酸（MAH-g-PLA），成功地将其制备为界面相容剂。通过熔融共混和注塑制备了添加不同比例相容剂的聚乳酸/木纤维/MAH-g-PLA复合材料，其中聚乳酸为基体相，木纤维为增强相。通过X射线衍射（XRD）、扫描电子显微镜（SEM）、热重分析仪（TGA）和动态热机械分析（DMA）研究了复合材料的结晶度、微观结构、热稳定性和动态热机械性能。此外，还对复合材料的力学性能和吸水性能进行了表征。结果表明，当MAH-g-PLA添加量为30%时，复合材料的拉伸强度和弯曲强度达到最高，此时复合材料的结晶度也显示出最高值。DMA结果表明，添加MAH-g-PLA界面相容剂提高了复合材料的损耗模量，改善了韧性。扫描电子显微镜（SEM）表明，使用MAH-g-PLA时，木纤维在聚乳酸基体相中分散良好，基体与增强相之间的界面相容性得到改善。因此，添加MAH-g-PLA可以提高聚乳酸/木纤维复合材料的界面相容性，改善复合材料的力学性能。
