He Hezhi, Wang Guozhen, Chen Ming, Xiong Chengtian, Li Yi, Tong Yi
National Engineering Research Center of Novel Equipment for Polymer Processing, Guangdong Provincial Key Laboratory of Technique and Equipment for Macromolecular Advanced Manufacturing, South China University of Technology, Guangzhou 510640, China.
Key Laboratory of Polymer Processing Engineering, Ministry of Education, South China University of Technology, Guangzhou 510640, China.
Materials (Basel). 2020 May 1;13(9):2094. doi: 10.3390/ma13092094.
In this report, poly(lactic acid) (PLA) and Poly(butylene adipate-co-terephthalate) (PBAT) with three kinds of compatibilizers were melt blended under intensive shear flow. A self-made parallel three-screw extruder was developed to generate such flow during the process. Mechanical properties, chemical reactions among PLA, PBAT and compatibilizers, rheological behavior and morphology were investigated. The mechanical tests showed that the notched impact strength of super-tough composite with 10 wt% EGMA is about 20 times than that of pure PLA. The Fourier transform infrared spectroscopy (FT-IR) results showed that the epoxy functional groups or maleic anhydride functional groups of KT-20, KT-915 and EGMA reacted with the hydroxyl groups of PLA or PBAT macromolecules, resulting in a bridge of PLA and PBAT. About rheological properties, the tan δ-angular frequency curves and the η''- η' curves confirmed the chemical reactions mentioned above and indicated better compatibility of η''- η' between PLA and PBAT, respectively. Meanwhile, the loss modulus and storage modulus-angular frequency curves demonstrated the discrepancy of different compatibilizer components. In particular, from scanning electron microscopy (SEM) images, it can be seen that the phase size and dispersion uniformity of PBAT adjusted by compatibilizer, corresponding to better compatibility that is described in the η''- η' curves. The approach for producing super-tough PLA/PBAT/compatibilizer by intensive shear flow provides a viable direction for further improving PLA performance.
在本报告中，聚乳酸（PLA）和聚己二酸丁二醇酯-对苯二甲酸丁二醇酯共聚物（PBAT）与三种增容剂在强剪切流作用下进行熔融共混。在此过程中，使用自行研制的平行三螺杆挤出机来产生这种流动。对其力学性能、PLA、PBAT与增容剂之间的化学反应、流变行为和形态进行了研究。力学测试表明，含10 wt%乙烯-甲基丙烯酸缩水甘油酯（EGMA）的超韧复合材料的缺口冲击强度约为纯PLA的20倍。傅里叶变换红外光谱（FT-IR）结果表明，KT-20、KT-915和EGMA的环氧官能团或马来酸酐官能团与PLA或PBAT大分子的羟基发生反应，形成了PLA与PBAT之间的桥梁。关于流变性能，损耗角正切-角频率曲线和η''-η'曲线证实了上述化学反应，并分别表明PLA与PBAT之间的η''-η'相容性更好。同时，损耗模量和储能模量-角频率曲线表明了不同增容剂组分的差异。特别是，从扫描电子显微镜（SEM）图像可以看出，增容剂调节了PBAT的相尺寸和分散均匀性，这与η''-η'曲线中描述的更好的相容性相对应。通过强剪切流制备超韧PLA/PBAT/增容剂的方法为进一步提高PLA性能提供了一个可行的方向。
