School of Food Science and Engineering, South China University of Technology, 510640, Guangzhou, China; Department of Plant and Environmental Sciences, University of Copenhagen, 1871, Frederiksberg C, Denmark.
School of Chemistry, University of Nottingham, NG7 2RD, Nottingham, United Kingdom.
Carbohydr Polym. 2021 Feb 1;253:117277. doi: 10.1016/j.carbpol.2020.117277. Epub 2020 Oct 22.
Thermoplastic, polysaccharide-based plastics are environmentally friendly. However, typical shortcomings include lack of water resistance and poor mechanical properties. Nanocomposite manufacturing using pure, highly linear, polysaccharides can overcome such limitations. Cast nanocomposites were fabricated with plant engineered pure amylose (AM), produced in bulk quantity in transgenic barley grain, and cellulose nanofibers (CNF), extracted from agrowaste sugar beet pulp. Morphology, crystallinity, chemical heterogeneity, mechanics, dynamic mechanical, gas and water permeability, and contact angle of the films were investigated. Blending CNF into the AM matrix significantly enhanced the crystallinity, mechanical properties and permeability, whereas glycerol increased elongation at break, mainly by plasticizing the AM. There was significant phase separation between AM and CNF. Dynamic plasticizing and anti-plasticizing effects of both CNF and glycerol were demonstrated by NMR demonstrating high molecular order, but also non-crystalline, and evenly distributed 20 nm-sized glycerol domains. This study demonstrates a new lead in functional polysaccharide-based bioplastic systems.
热塑性、多糖基塑料具有环境友好性。然而，典型的缺点包括缺乏耐水性和较差的机械性能。使用纯的、高度线性的多糖制造纳米复合材料可以克服这些限制。采用植物工程纯直链淀粉（AM）和从农业废弃物糖甜菜浆中提取的纤维素纳米纤维（CNF）制造铸造型纳米复合材料。研究了薄膜的形态、结晶度、化学异质性、力学性能、动态力学性能、气体和水分渗透性以及接触角。将 CNF 混入 AM 基体中显著提高了结晶度、力学性能和渗透性，而甘油的加入则通过增塑 AM 显著提高了断裂伸长率。AM 和 CNF 之间存在明显的相分离。NMR 证明了 CNF 和甘油的动态塑化和抗塑化作用，表明存在高分子有序，但也存在非晶态和均匀分布的 20nm 大小的甘油域。这项研究为功能性多糖基生物塑料系统提供了一个新的研究方向。
