Abstract The present study describes the fabrication and characterization of eco-friendly composites based on high density polyethylene (HDPE), poly (lactic acid) (PLA) with microcrystalline cellulose (MCC) fibres via melt extrusion followed by injection moulding. The morphology of PLA in both HDPE/PLA blends and HDPE/MCC fibres composites was irregular and immiscible. The tensile strength at max load and % elongation at break of all polyblend composites were reduced to ~17%, ~15%, and ~84%, ~89% than pure HDPE matrix, respectively. The toughness of HDPE and its polyblend composites were decreased to ~92% and ~91%, respectively. As higher number indicates greater resistance, the hardness of HDPE was improved by ~7% and ~10% after adding PLA followed by MCC fibres. As revealed from DSC analysis, the crystallinity of composites was considerably influenced by the MCC fibres content due to the transcrystallization effect. The crystallinity of HDPE/PLA with MCC fibres polyblend composites was decreased by ~41% as compared to the HDPE matrix because of disorientation of fibres as seen in X-ray diffraction analysis. Eventually, the results revealed that the presence or absence of MCC fibre loading had significant effects on the mechanical, morphological, and thermal properties of HDPE/PLA blends.

中文翻译：

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微晶纤维素 [MCC] 纤维对高密度聚乙烯 [HDPE]/聚乳酸 [PLA] 共混物的形态和结晶行为的影响

摘要 本研究描述了基于高密度聚乙烯 (HDPE)、聚乳酸 (PLA) 和微晶纤维素 (MCC) 纤维的环保复合材料的制造和表征，通过熔融挤出和注塑成型。HDPE/PLA 共混物和 HDPE/MCC 纤维复合材料中 PLA 的形态是不规则且不混溶的。与纯 HDPE 基体相比，所有聚共混物复合材料的最大载荷拉伸强度和断裂伸长率百分比分别降低至 ~17%、~15% 和 ~84%、~89%。HDPE 及其共混复合材料的韧性分别降低至~92% 和~91%。由于数字越大表明阻力越大，在加入 PLA 和 MCC 纤维后，HDPE 的硬度提高了约 7% 和约 10%。DSC分析表明，由于转晶效应，复合材料的结晶度受 MCC 纤维含量的显着影响。与 HDPE 基体相比，HDPE/PLA 与 MCC 纤维共混复合材料的结晶度降低了约 41%，这是因为 X 射线衍射分析中所见的纤维取向紊乱。最终，结果表明，MCC 纤维负载的存在与否对 HDPE/PLA 共混物的机械、形态和热性能有显着影响。