Department of Chemical Engineering, Indian Institute of Technology, Guwahati, Assam, India.
Department of Civil Engineering, Indian Institute of Technology, Guwahati, Assam, India.
Chemosphere. 2020 May;247:125875. doi: 10.1016/j.chemosphere.2020.125875. Epub 2020 Jan 9.
The present study evaluates biodegradation of the polyblends of poly(lactic acid) (PLA), polycaprolactone (PCL) and microcrystalline cellulose (MCC) in different compositions and comparison of the properties of those blends with that of neat PLA and neat PCL. The samples were melt extruded and blended to evaluate the environmental fate of the polyblends under simulated composting conditions following the standard ASTM International D5338-15 protocol. It was seen that blends with a higher concentration of PCL and MCC in the PLA matrix showed higher carbon mineralization percentage in comparison to the blends having low PCL and MCC components. Molecular weight analysis of the samples showed a decrease in their weight due to chain scission mechanism leading to the formation of intermediates. Analytical techniques revealed the formation of microbial biofilms on the blended biopolymeric surfaces. Field emission scanning electron microscopy showed the formation of fibril-like structures by PLA, and the formation of rough patches on the PCL surface re-confirmed biodegradation of the samples. This work fuels interest in the material characterization of PLA/PCL/MCC based polyblends and helps in tuning the biodegradability of the studied samples according to the demands.
本研究评估了聚乳酸(PLA)、聚己内酯(PCL)和微晶纤维素(MCC)的共混物在不同组成下的生物降解性,并比较了这些共混物与纯 PLA 和纯 PCL 的性能。采用熔融共混法制备了共混物样品,并按照 ASTM 国际标准 D5338-15 协议下的模拟堆肥条件来评估共混物的环境命运。结果表明,与含有低 PCL 和 MCC 成分的共混物相比,在 PLA 基质中具有更高 PCL 和 MCC 浓度的共混物显示出更高的碳矿化百分比。样品的分子量分析表明,由于链断裂机制导致中间产物的形成,其重量有所下降。分析技术揭示了微生物生物膜在共混生物聚合物表面的形成。场发射扫描电子显微镜显示 PLA 形成了纤维状结构,而 PCL 表面形成了粗糙斑块,这再次证实了样品的生物降解。这项工作激发了人们对 PLA/PCL/MCC 基共混物的材料特性研究的兴趣,并有助于根据需求调整研究样品的生物降解性。