Polyoxymethylene (POM) is a semicrystalline thermoplastic that displays high tensile strength, thermal stability, and chemical durability. However, its widespread application is limited by its low elongation at break and thermal durability. In the present study, nanosilica (NS) and polylactic acid-grafted polyethylene glycol (PELA) were used as enhancement additives to improve the performance of POM homopolymer. Specifically, the POM/PELA/NS nanocomposites with a fixed NS content and varying PELA contents were prepared by a melt mixing method. The influence of the additives on the processability, and dynamic thermo-mechanical and tensile properties of the nanocomposites was evaluated by comparing the torque, mixing energy at melt state, storage modulus, shear stress, loss modulus, tan δ, tensile strength, elongation at break and thermal degradation of the nanocomposites. The results showed that the combined addition of NS and PELA enhanced the thermal stability, tensile strength, elongation at break and chemical stability of the POM/PELA/NS nanocomposites owing to the good compatibility between PELA and the POM matrix. Furthermore, the morphology, and UV and ozone durability of POM and the nanocomposites were assessed and discussed.

中文翻译：

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聚甲醛/二氧化硅/聚乳酸接枝的聚乙二醇纳米复合材料：结构、形态和机械性能以及臭氧和紫外线耐久性

聚甲醛 (POM) 是一种半结晶热塑性塑料，具有高拉伸强度、热稳定性和化学耐久性。然而，它的广泛应用受到其低断裂伸长率和热耐久性的限制。在本研究中，纳米二氧化硅（NS）和聚乳酸接枝聚乙二醇（PELA）被用作增强添加剂，以改善POM均聚物的性能。具体而言，通过熔融混合法制备了具有固定 NS 含量和不同 PELA 含量的 POM/PELA/NS 纳米复合材料。通过比较扭矩、熔融状态下的混合能、储能模量、剪切应力、损耗模量、tan δ来评估添加剂对纳米复合材料的可加工性、动态热机械和拉伸性能的影响 ，拉伸强度，断裂伸长率和纳米复合材料的热降解。结果表明，由于PELA与POM基体具有良好的相容性，NS和PELA的联合添加提高了POM/PELA/NS纳米复合材料的热稳定性、拉伸强度、断裂伸长率和化学稳定性。此外，对 POM 和纳米复合材料的形态、紫外线和臭氧耐受性进行了评估和讨论。