Purpose

The purpose of this study was to develop antimicrobial bioplastics based on Poly Lactic Acid (PLA) with the addition of chitosan-ZnO, and chitosan-TiO₂ to improve antimicrobial properties.

Methods

For the preparation of the bioplastics, PLA with chitosan-ZnO or chitosan-TiO₂ were used. The antimicrobial activity, mechanical and thermal properties, and water vapor permeability of bioplastics were evaluated.

Results

PLA-chitosan-ZnO indicated a robust antimicrobial activity against bacteria such as Salmonella typhi, Bacillus subtilis, Escherichia coli, Staphylococcus aureus, yeast such as Candida albicans, and fungus Aspergillus niger. No formation of new functional groups in PLA-chitosan-ZnO composites. In comparison to other PLA-based bioplastics, this bioplastic has medium tensile strength, tensile modulus, and elongation percentages with low barrier ability to water vapor. Chitosan-ZnO itself has a greater tensile strength compared to chitosan-TiO₂. These two compounds undergo 2 stages of decomposition in a temperature range of 43 °C to 265 °C. The addition of PLA into chitosan-ZnO or chitosan TiO₂ causes the bioplastics decomposed in a single stage. It also increases the decomposition temperature of bioplastic. However, compared to chitosan-ZnO or TiO₂, the PLA-chitosan-ZnO or TiO₂ bioplastics tend to produce a fragile composite indicating by decrease in their tensile strength.

Conclusion

In general, the addition of chitosan-ZnO into in PLA-based bioplastic produces better antimicrobial properties compared to TiO₂.

中文翻译：

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添加 TiO 2 和 ZnO 的基于 PLA-壳聚糖的新型抗菌生物塑料

目的

本研究的目的是开发基于聚乳酸 (PLA) 并添加壳聚糖-ZnO 和壳聚糖-TiO ₂的抗菌生物塑料，以提高抗菌性能。

方法

对于生物塑料的制备，使用具有壳聚糖-ZnO 或壳聚糖-TiO ₂的PLA。评估了生物塑料的抗菌活性、机械和热性能以及水蒸气渗透性。

结果

PLA-壳聚糖-ZnO对细菌如伤寒杆菌、枯草杆菌、大肠杆菌、金黄色葡萄球菌、酵母如白色念珠菌和真菌黑曲霉具有强大的抗菌活性。PLA-壳聚糖-ZnO复合材料中没有形成新的官能团。与其他基于 PLA 的生物塑料相比，这种生物塑料具有中等的拉伸强度、拉伸模量和伸长率，并且对水蒸气的阻隔能力较低。_{与壳聚糖-TiO 2}相比，壳聚糖-ZnO本身具有更大的抗拉强度. 这两种化合物在 43 °C 至 265 °C 的温度范围内经历 2 个分解阶段。将PLA添加到壳聚糖-ZnO或壳聚糖TiO ₂中会导致生物塑料在一个阶段分解。它还提高了生物塑料的分解温度。然而，与壳聚糖-ZnO 或 TiO ₂相比，PLA-壳聚糖-ZnO 或 TiO ₂生物塑料倾向于产生易碎的复合材料，这表明它们的拉伸强度降低。

结论

一般来说，与 TiO ₂相比，在 PLA 基生物塑料中添加壳聚糖-ZnO 会产生更好的抗菌性能。