Abstract While PLA possesses modest to good strength and stiffness, broader application is hindered by its brittle nature. The aim of this study was to develop strong and tough polymeric materials from renewable biomaterials and understand the underlying interactions and mechanisms. Cellulose nanofibrils (CNFs) and epoxidized soybean oil (ESO) were compounded with poly(lactic acid) (PLA) to create a PLA-CNF-ESO tertiary nanocomposite system. Tensile and dynamic mechanical analyses were performed to see how variations in ESO and CNF content affect mechanical properties such as strength, modulus, ductility, and toughness. It was found that at low CNF levels (10 wt%) the addition of ESO can improve the ductility of the nanocomposites 5- to 10-fold with only slight losses in strength and modulus, while at higher CNF levels (20 and 30 wt%), ESO exhibited little effect on mechanical properties, possibly due to percolation of CNFs in the matrix, dominating stress transfer. Therefore, it is important to optimize CNF and ESO amounts in composites to achieve materials with both high strength and high toughness. Efforts have been made to understand the underlying mechanisms of the mechanical behavior of one class of these composites via thermal, dynamic mechanical, rheological, morphological, and Raman analyses.

中文翻译：

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通过生物环氧树脂相互作用增韧纳米纤维素/PLA复合材料：机理研究

摘要 虽然 PLA 具有适度到良好的强度和刚度，但其脆性阻碍了其更广泛的应用。本研究的目的是从可再生生物材料中开发强韧的聚合物材料，并了解潜在的相互作用和机制。纤维素纳米原纤维 (CNF) 和环氧化大豆油 (ESO) 与聚乳酸 (PLA) 复合，形成 PLA-CNF-ESO 三级纳米复合系统。进行了拉伸和动态力学分析，以了解 ESO 和 CNF 含量的变化如何影响强度、模量、延展性和韧性等机械性能。结果发现，在低 CNF 水平（10 wt%）下，添加 ESO 可以将纳米复合材料的延展性提高 5 到 10 倍，而强度和模量只有轻微损失，而在较高 CNF 水平（20 和 30 wt%）下), ESO 对机械性能几乎没有影响，这可能是由于基体中 CNF 的渗透，主导了应力传递。因此，重要的是优化复合材料中 CNF 和 ESO 的含量，以获得兼具高强度和高韧性的材料。已经努力通过热分析、动态力学、流变学、形态学和拉曼分析来了解一类这些复合材料的机械行为的潜在机制。