Institute of Agriculture and Food Engineering, Kunming University of Science and Technology, Kunming, China.
School of Chemical Engineering and Energy Technology, Dongguan University of Technology, Dongguan, China.
J Sci Food Agric. 2021 Sep;101(12):4925-4933. doi: 10.1002/jsfa.11136. Epub 2021 Mar 1.
Our living environment is being increasingly polluted by petroleum-based plastics and there is an increasing demand for biodegradable food packaging. In this study, the effect of various ultrahigh-pressure (UHP) treatments (0, 200 and 400 MPa) on the microstructure and thermal, barrier and mechanical properties of poly(lactic acid) (PLA)/ZnO nanocomposite films was studied.
The film-forming solution was processed using UHP technology. The crystallinity, strength and stiffness of the composite film after UHP treatment increased. In addition, barrier property analysis showed that the UHP treatment significantly (P < 0.05) reduced the oxygen permeability and water vapor permeability (WVP) coefficient of the PLA/ZnO nanocomposite film. Furthermore, the WVP value of the film treated at 400 MPa (50 g kg nano-ZnO content) was the lowest and reduced by 47.3% compared with that of pure PLA film. The improvement in these properties might be due to the interaction between nano-ZnO and PLA matrix promoted by UHP treatment.
Therefore, the application of UHP technology on the film-forming solution could improve the crystallinity and functional properties of the nanocomposite film, and has great potential in the production of food packaging films with ideal functions. © 2021 Society of Chemical Industry.
我们的生活环境正日益受到石油基塑料的污染，对可生物降解的食品包装的需求也在不断增加。在本研究中，研究了各种超高压（UHP）处理（0、200 和 400 MPa）对聚乳酸（PLA）/ZnO 纳米复合材料薄膜的微观结构和热、阻隔及力学性能的影响。
使用 UHP 技术对成膜溶液进行处理。UHP 处理后，复合膜的结晶度、强度和刚性增加。此外，阻隔性能分析表明，UHP 处理显著（P < 0.05）降低了 PLA/ZnO 纳米复合材料薄膜的氧气透过率和水蒸气透过系数（WVP）。此外，在 400 MPa（50 g kg 纳米 ZnO 含量）下处理的薄膜的 WVP 值最低，与纯 PLA 薄膜相比降低了 47.3%。这些性能的提高可能是由于 UHP 处理促进了纳米 ZnO 与 PLA 基质之间的相互作用。
因此，将 UHP 技术应用于成膜溶液可以提高纳米复合材料薄膜的结晶度和功能特性，在生产具有理想功能的食品包装薄膜方面具有很大的潜力。 © 2021 英国化学学会。
