Poly(amino acid) (PAA)-based nanocomposites were synthesized by in situ melting polycondensation with addition of different contents of ZnO nanoparticles (ZnO NPs); the morphology and thermal, mechanical, cytotoxicity, antibacterial and dielectric properties of the resulting nanocomposites were investigated and characterized. The nanoparticles were dispersed within the matrix without the need for coupling agent and surfactants. The crystallization temperature had a gradual rise with increasing ZnO NP loading, confirming that the nanoparticles act as nucleating agents for PAA crystallization. The nanoparticles increased the thermal stability of the matrix. The mechanical properties were gradually enhanced by increasing the ZnO NP content except for the elongation at break, which showed its highest value at 1 wt% ZnO NP contents. They also exhibited active inhibition against both Gram-positive and Gram-negative bacteria, which was gradually enhanced with increase in ZnO NP content. Meanwhile, the nanocomposites showed no obvious cytotoxicity. Thus, these nanocomposites are suitable as performance materials in the field of medical apparatus.

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具有增强的热、机械和抗菌性能的聚（氨基酸）/氧化锌纳米颗粒纳米复合材料

通过加入不同含量的氧化锌纳米颗粒（ZnO NPs），通过原位熔融缩聚反应合成了基于聚氨基酸（PAA）的纳米复合材料；研究并表征了所得纳米复合材料的形态和热、机械、细胞毒性、抗菌和介电性能。纳米颗粒分散在基质中，不需要偶联剂和表面活性剂。结晶温度随着 ZnO NP 负载量的增加而逐渐升高，证实纳米颗粒充当 PAA 结晶的成核剂。纳米颗粒增加了基质的热稳定性。除了断裂伸长率外，随着 ZnO NP 含量的增加，力学性能逐渐增强，断裂伸长率在 1 wt% ZnO NP 含量时表现出最高值。它们还对革兰氏阳性菌和革兰氏阴性菌表现出积极的抑制作用，这种抑制作用随着 ZnO NP 含量的增加而逐渐增强。同时，纳米复合材料没有表现出明显的细胞毒性。因此，这些纳米复合材料适合作为医疗器械领域的性能材料。