Graduate Program in Materials Science, Technology Center, Federal University of Piauí, Teresina, PI 64049-550, Brazil.
Graduate Program in Materials Engineering, Federal Institute of Education, Science and Technology of Piauí, Teresina, PI 64000-040, Brazil.
Carbohydr Polym. 2017 Jul 15;168:52-60. doi: 10.1016/j.carbpol.2017.03.054. Epub 2017 Mar 19.
The solid waste management problems caused by the accumulation of plastics require measures to mitigate the environmental damage, and mechanical recycling of plastics is among the possible solutions. In this context, the present study aimed to evaluate the effects of mechanical recycling on the properties of a polypropylene/poly(butylene adipate co-terephthalate)-thermoplastic starch blend (PP/PBAT-Thermoplastic starch blend) when it was subjected to seven reprocessing cycles by a single-screw extruder. The observations by infrared spectroscopy indicated that the chemical structures of the blend and the polypropylene matrix did not present significant changes with the reprocessing cycles. The X-ray diffraction analyses showed that the PP crystals were most affected when reprocessed in their pure form. The observations by thermogravimetry and differential scanning calorimetry indicated that the thermal stability of the blend was higher than that of polypropylene during the extrusion cycles. The scanning electron microscopy images indicated a weak interfacial interaction between the components of the blend, and the mechanical properties showed that the reprocessing improved the elasticity modulus and yield stress, with a consequential decrease of the impact strength.
塑料积累造成的固体废物管理问题需要采取措施减轻环境破坏，而塑料的机械回收是可能的解决方案之一。在此背景下，本研究旨在评估机械回收对聚丙烯/聚（己二酸丁二醇酯-co-对苯二甲酸丁二醇酯）-热塑性淀粉共混物（PP/PBAT-热塑性淀粉共混物）性能的影响，该共混物在单螺杆挤出机中经过七次再加工循环。通过红外光谱观察表明，共混物和聚丙烯基质的化学结构在再加工循环中没有发生显著变化。X 射线衍射分析表明，当以纯形式再加工时，PP 晶体受到的影响最大。热重分析和差示扫描量热法观察表明，在挤出循环过程中，共混物的热稳定性高于聚丙烯。扫描电子显微镜图像表明，共混物各组分之间的界面相互作用较弱，力学性能表明，再加工提高了弹性模量和屈服应力，同时冲击强度降低。
