Nanoparticles of zinc oxide (ZnO), polyhedral oligomeric silsesquioxane (POSS), and their hybrids were added to polylactic acid (PLA) using solution casting process at different weight percentages of the nanoparticles (1, 3, and 5 wt%) to form developed nanocomposites for food packaging applications. According to FTIR and XRD studies, both nanoparticles displayed fair chemical interactions with the PLA matrix. Furthermore, morphological investigations (SEM-EDS) revealed that POSS, ZnO, and their hybrids were uniformly dispersed into the matrix despite some microaggregations at 5 wt% of nanoparticles, especially for those containing POSS. Moreover, adding 1 wt% of POSS to PLA increased its tensile strength and modulus by 20% and 149%, respectively, while decreasing the elongation-at-break by 54%. In addition, the tensile strength, tensile modulus, and elongation-at-break of PLA all increased by 7.5%, 28.7%, and 162%, respectively, with the addition of 1 wt% ZnO. Contact angle and surface free energy experiments demonstrated that after incorporating ZnO and POSS into the PLA matrix, the hydrophobicity of the samples increased, and POSS nanoparticles could minimize bacterial adherence effectively. In addition to the antibacterial properties of ZnO and POSS nanoparticles, increasing the concentration of hybrid nanoparticles up to 5 wt% expanded the bacteria's inhibitory zone, particularly in the case of Gram-positive bacteria (Staphylococcus aureus). Finally, the hybrid nanocomposites exhibited both balanced mechanical characteristics and promising antibacterial activity compared with those with ZnO and POSS alone.

中文翻译：

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用杂化氧化锌-多面体低聚倍半硅氧烷纳米粒子增强的聚（乳酸）膜：形态学、机械和抗菌性能

将氧化锌 (ZnO) 纳米粒子、多面体低聚倍半硅氧烷 (POSS) 及其杂化物添加到聚乳酸 (PLA) 中，采用溶液浇铸工艺以不同重量百分比的纳米粒子（1、3 和 5 wt%）形成显影用于食品包装应用的纳米复合材料。根据 FTIR 和 XRD 研究，两种纳米粒子都显示出与 PLA 基质的良好化学相互作用。此外，形态学研究 (SEM-EDS) 显示 POSS、ZnO 及其杂化物均匀分散到基质中，尽管在 5 wt% 的纳米颗粒下存在一些微聚集，特别是对于含有 POSS 的纳米颗粒。此外，在 PLA 中添加 1 wt% 的 POSS 可使其拉伸强度和模量分别增加 20% 和 149%，同时将断裂伸长率降低 54%。此外，拉伸强度、拉伸模量、添加 1 wt% ZnO 后，PLA 的断裂伸长率分别提高了 7.5%、28.7% 和 162%。接触角和表面自由能实验表明，将 ZnO 和 POSS 掺入 PLA 基质后，样品的疏水性增加，POSS 纳米颗粒可以有效减少细菌粘附。除了 ZnO 和 POSS 纳米粒子的抗菌特性外，将混合纳米粒子的浓度增加到 5 wt% 会扩大细菌的抑制区，特别是在革兰氏阳性细菌的情况下（样品的疏水性增加，POSS纳米颗粒可以有效地减少细菌粘附。除了 ZnO 和 POSS 纳米粒子的抗菌特性外，将混合纳米粒子的浓度增加到 5 wt% 会扩大细菌的抑制区，特别是在革兰氏阳性细菌的情况下（样品的疏水性增加，POSS纳米颗粒可以有效地减少细菌粘附。除了 ZnO 和 POSS 纳米粒子的抗菌特性外，将混合纳米粒子的浓度增加到 5 wt% 会扩大细菌的抑制区，特别是在革兰氏阳性细菌的情况下（金黄色葡萄球菌）。最后，与单独使用 ZnO 和 POSS 的纳米复合材料相比，杂化纳米复合材料表现出平衡的机械特性和有前途的抗菌活性。