Balu Rajkamal, Sharma Swati, Roberts Rachael, Vongsvivut Jitraporn, Choudhury Namita Roy
Chemical and Environmental Engineering, School of Engineering, STEM College, RMIT University, Melbourne, VIC 3000, Australia.
ARC Industrial Transformation Research Hub for Transformation of Reclaimed Waste into Engineered Materials and Solutions for a Circular Economy (TREMS), RMIT University, Melbourne, VIC 3000, Australia.
Polymers (Basel). 2024 Sep 18;16(18):2631. doi: 10.3390/polym16182631.
The need for ending plastic waste and creating a circular economy has prompted significant interest in developing a new family of composite materials through recycling and recovery of waste resources (including bio-sourced materials). In this work, a family of natural fiber-reinforced plastic composites has been developed from paint pail waste recycled polypropylene (rPP) and waste wool fibers of different diameter and aspect ratio. Composites were fabricated by melt processing using polypropylene-graft-maleic anhydride as a compatibilizer. The internal morphology, interfacial and thermal characteristics, viscoelastic behavior, water sorption/wettability, and mechanical properties of composites were studied using electron microscopy, high-resolution synchrotron Fourier transform infrared microspectroscopy, thermal analysis, rheology, immersion test, contact angle measurement, tensile test and flexural test. The composite matrix exhibited an internal morphology of coalescent micro-droplets due to the presence of polyethylene and dry paint in the rPP phase. In general, the rheological and mechanical properties of the composites comprising higher-aspect-ratio (lower diameter) fibers exhibited relatively superior performance. About an 18% increase in tensile strength and a 39% increase in flexural strength were measured for composites with an optimal fiber loading of 10 wt.%. Interfacial debonding and fiber pull-out were observed as the main failure mechanism of the composites. The developed composites have potential for applications in automotive, decking, and building industries.
终结塑料垃圾并创建循环经济的需求，引发了人们对通过回收和再利用废弃资源（包括生物源材料）来开发新型复合材料家族的浓厚兴趣。在这项工作中，利用回收自油漆桶的聚丙烯（rPP）以及不同直径和长径比的废羊毛纤维，开发出了一种天然纤维增强塑料复合材料家族。复合材料通过熔融加工制备，使用聚丙烯接枝马来酸酐作为增容剂。采用电子显微镜、高分辨率同步辐射傅里叶变换红外光谱显微镜、热分析、流变学、浸泡试验、接触角测量、拉伸试验和弯曲试验，研究了复合材料的内部形态、界面和热特性、粘弹性行为、吸水性/润湿性以及力学性能。由于rPP相中存在聚乙烯和干油漆，复合基体呈现出聚结微滴的内部形态。总体而言，包含高长径比（低直径）纤维的复合材料的流变学和力学性能表现出相对优异的性能。对于纤维最佳负载量为10 wt.%的复合材料，测得其拉伸强度提高了约18%，弯曲强度提高了39%。观察到界面脱粘和纤维拔出是复合材料的主要失效机制。所开发的复合材料在汽车、地板和建筑行业具有应用潜力。
