Lu Xiang, Kang Benhao, Shi Shengyu
Key Laboratory of Polymer Processing Engineering of the Ministry of Education, National Engineering Research Center of Novel Equipment for Polymer Processing, Guangdong Key Laboratory of Technique and Equipment for Macromolecular Advanced Manufacturing, South China University of Technology, Guangzhou 510641, China.
Polymers (Basel). 2019 Sep 27;11(10):1583. doi: 10.3390/polym11101583.
The electrically conductive poly (lactic acid) (PLA)/recycled high-density polyethylene (HDPE)/carbon black (CB) composites with a fine co-continuous micro structure and selective localization of CB in the HDPE component were fabricated by one-step melt processing via a twin-screw extruder. Micromorphology analysis, electrical conductivity, thermal properties, thermal stability, and mechanical properties were investigated. Scanning electron microscope (SEM) images indicate that a co-continuous morphology is formed, and CB is selectively distributed in the HDPE component. With the introduction of CB, the phase size of the PLA component and the HDPE component in PLA/HDPE blends is reduced. In addition, differential scanning calorimetry (DSC) and thermos gravimetric analysis (TGA) results show that the introduction of CB promotes the crystallization behavior of the PLA and HDPE components, respectively, and improves the thermal stability of PLA70/30HDPE/CB composites. The electrically conductive percolation threshold of the PLA70/30HDPE/CB composites is around 5.0 wt %, and the electrical conductivity of PLA70/30HDPE/CB composites reaches 1.0 s/cm and 15 s/cm just at the 10 wt % and 15 wt % CB loading, respectively. Further, the tensile and impact tests show that the PLA70/30HDPE/CB composites have good mechanical properties. The excellent electrical conductivity and good mechanical properties offer the potential to broaden the application of PLA/HDPE/CB composites.
通过双螺杆挤出机一步熔融加工制备了具有精细共连续微观结构且炭黑（CB）在高密度聚乙烯（HDPE）组分中选择性定位的导电聚乳酸（PLA）/回收高密度聚乙烯（HDPE）/炭黑（CB）复合材料。研究了其微观形态、电导率、热性能、热稳定性和力学性能。扫描电子显微镜（SEM）图像表明形成了共连续形态，且CB选择性地分布在HDPE组分中。随着CB的引入，PLA/HDPE共混物中PLA组分和HDPE组分的相尺寸减小。此外，差示扫描量热法（DSC）和热重分析（TGA）结果表明，CB的引入分别促进了PLA和HDPE组分的结晶行为，并提高了PLA70/30HDPE/CB复合材料的热稳定性。PLA70/30HDPE/CB复合材料的导电渗流阈值约为5.0 wt%，在CB含量为10 wt%和15 wt%时，PLA70/30HDPE/CB复合材料的电导率分别达到1.0 s/cm和15 s/cm。此外，拉伸和冲击试验表明PLA70/30HDPE/CB复合材料具有良好的力学性能。优异的导电性和良好的力学性能为拓宽PLA/HDPE/CB复合材料的应用提供了潜力。
