Li Wenhui, Zhang Cheng, Chi Hai, Li Lin, Lan Tianqing, Han Peng, Chen Haiyan, Qin Yuyue
Institute of Yunnan Food Safety, Kunming University of Science and Technology, Kunming 650550, China.
College of Light Industry and Food Science, South China University of Technology, Guangzhou 510640, China.
Molecules. 2017 Jul 13;22(7):1170. doi: 10.3390/molecules22071170.
Polylactide (PLA)/nano-TiO₂ and PLA/nano-TiO₂/nano-Ag blends films were prepared by a solvent volatilization method. Compared to pure PLA film, the nano-blend films have low water vapor permeability (WVP) and a poor transparency. With the increase of the NPs in the PLA, the tensile strength (TS) and elastic modulus (EM) decreased, while the elongation at break (ε) increased. SEM analysis indicated a rougher cross-section of the nano-blend films. According to the FTIR analysis, no new chemical bonds were formed in the nano-blend films. By using DSC to examine the crystallization and melting behavior, the result shows that the NPs have no effect on the glass transition (T) and melting temperature (T), but they caused an increase on the cold crystallization (T and crystallinity (). TGA results show that the addition of nanoparticles significantly improved the thermal stability. The PLA nano-blend films show a good antimicrobial activity against. and . Most important, we carried out migration tests, and verified that the release of NPs from the nano-blend films was within the standard limits.
采用溶剂挥发法制备了聚乳酸（PLA）/纳米TiO₂和PLA/纳米TiO₂/纳米Ag共混薄膜。与纯PLA薄膜相比，纳米共混薄膜具有较低的水蒸气透过率（WVP）和较差的透明度。随着PLA中纳米粒子（NPs）含量的增加，拉伸强度（TS）和弹性模量（EM）降低，而断裂伸长率（ε）增加。扫描电子显微镜（SEM）分析表明纳米共混薄膜的横截面更粗糙。根据傅里叶变换红外光谱（FTIR）分析，纳米共混薄膜中未形成新的化学键。通过差示扫描量热法（DSC）研究结晶和熔融行为，结果表明NPs对玻璃化转变温度（Tg）和熔点（Tm）没有影响，但导致冷结晶温度（Tc）和结晶度（χc）升高。热重分析（TGA）结果表明，纳米粒子的加入显著提高了热稳定性。PLA纳米共混薄膜对……和……表现出良好的抗菌活性。最重要的是，我们进行了迁移测试，并验证了纳米共混薄膜中NPs的释放量在标准范围内。
