Potrč Sanja, Kraševac Glaser Tjaša, Vesel Alenka, Poklar Ulrih Nataša, Fras Zemljič Lidija
Laboratory for Characterization and Processing of Polymers, Faculty of Mechanical Engineering, University of Maribor, Smetanova 17, SI-2000 Maribor, Slovenia.
Faculty of Chemistry and Chemical Engineering, University of Maribor, Smetanova 17, SI-2000 Maribor, Slovenia.
Polymers (Basel). 2020 Aug 19;12(9):1855. doi: 10.3390/polym12091855.
Two-layer functional coatings for polyethylene (PE) and polypropylene (PP) films were developed for the active packaging concept. Prior to coating, the polymer films were activated by O and NH plasma to increase their surface free energy and to improve the binding capacity and stability of the coatings. The first layer was prepared from a macromolecular chitosan solution, while the second (upper) layer contained chitosan particles with embedded catechin or pomegranate extract. Functionalized films were analyzed physico-chemically to elemental composition using ATR-FTIR spectroscopy and XPS. Further, oxygen permeability and wettability (Contact Angle) were examined. The antimicrobial properties were analyzed by the standard ISO 22196 method, while the antioxidative properties were determined with an ABTS assay. Functionalized films show excellent antioxidative and antimicrobial efficacy. A huge decrease in oxygen permeability was achieved in addition. Moreover, a desorption experiment was also performed, confirming that the migration profile of a compound from the surfaces was in accordance with the required overall migration limit. All these properties indicate the great potential of the developed active films/foils for end-uses in food packaging.
为实现活性包装概念，开发了用于聚乙烯（PE）和聚丙烯（PP）薄膜的双层功能涂层。在涂覆之前，通过氧等离子体和氮等离子体对聚合物薄膜进行活化，以提高其表面自由能，并改善涂层的结合能力和稳定性。第一层由大分子壳聚糖溶液制备，而第二层（上层）包含嵌入儿茶素或石榴提取物的壳聚糖颗粒。使用衰减全反射傅里叶变换红外光谱（ATR-FTIR）和X射线光电子能谱（XPS）对功能化薄膜的元素组成进行了物理化学分析。此外，还检测了氧气透过率和润湿性（接触角）。通过标准ISO 22196方法分析抗菌性能，同时用ABTS法测定抗氧化性能。功能化薄膜显示出优异的抗氧化和抗菌功效。此外，氧气透过率大幅降低。此外，还进行了脱附实验，证实化合物从表面的迁移情况符合所需的总迁移限量。所有这些特性表明，所开发的活性薄膜/箔片在食品包装终端应用中具有巨大潜力。
