Noulis Konstantinos, Frangopoulos Theofilos, Arampatzidou Athanasia, Tsekmes Lazaros, Marinopoulou Anna, Goulas Athanasios, Karageorgiou Vassilis
Food Process Engineering Laboratory, Department of Food Science and Technology, International Hellenic Univeristy, P.O. Box 141, 57400 Thessaloniki, Greece.
Polymers (Basel). 2023 Aug 25;15(17):3540. doi: 10.3390/polym15173540.
Synthetic polymers are the main food packaging material, although they are nonbiodegradable and their recycling process is expensive. A biodegradable, eco-friendly material, with high availability and low cost, such as starch, is a promising solution for the production of films for food packaging. To enhance starch film mechanical and barrier properties, nanoclays have been incorporated within the film matrix. Crosslinking is a well-established method to modify starch properties, but it has not been investigated in combination with nanoclay addition. In the present study, films were developed with starch that was crosslinked through the addition of 5, 15, and 40% wt. sodium trimetaphosphate (STMP) based on dry starch weight. To investigate the interaction between crosslinking and nanoclay addition, montmorillonite (MMT) was added at a 10.5% wt. concentration based on dry starch weight. Experimental data revealed a synergistic effect between STMP crosslinking and MMT addition regarding film thickness, elongation at break, color properties, and opacity. Regarding barrier properties, MMT addition negated the effect of STMP crosslinking, while, in the case of moisture content, it did not alter the effect of STMP crosslinking. Finally, in the case of tensile strength, a synergistic effect followed by a negative interaction was observed. In conclusion, the addition of MMT can potentially enhance, alongside crosslinking, some properties of the films, while other properties are not affected any more than just by crosslinking.
合成聚合物是主要的食品包装材料，尽管它们不可生物降解且回收过程成本高昂。一种具有高可用性和低成本的可生物降解、环保材料，如淀粉，是用于生产食品包装薄膜的一种有前景的解决方案。为了提高淀粉薄膜的机械性能和阻隔性能，纳米黏土已被掺入薄膜基质中。交联是一种成熟的改性淀粉性能的方法，但尚未对其与添加纳米黏土相结合进行研究。在本研究中，基于干淀粉重量，通过添加5%、15%和40%重量的偏磷酸三钠（STMP）来交联淀粉，从而制备薄膜。为了研究交联与添加纳米黏土之间的相互作用，基于干淀粉重量，以10.5%的重量浓度添加蒙脱石（MMT）。实验数据表明，在薄膜厚度、断裂伸长率、颜色特性和不透明度方面，STMP交联与添加MMT之间存在协同效应。关于阻隔性能，添加MMT抵消了STMP交联的效果，而在水分含量方面，它并未改变STMP交联的效果。最后，在拉伸强度方面，观察到先是协同效应，随后是负相互作用。总之，添加MMT除了交联之外，还可能潜在地增强薄膜的一些性能，而其他性能受影响程度不会超过仅通过交联所产生的影响。
