Department of Plant and Environmental Sciences, University of Copenhagen, Denmark.
Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark.
Carbohydr Polym. 2017 Sep 15;172:237-245. doi: 10.1016/j.carbpol.2017.05.043. Epub 2017 May 20.
Grain polysaccharides represent potential valuable raw materials for next-generation advanced and environmentally friendly plastics. Thermoplastic starch (TPS) is processed using conventional plastic technology, such as casting, extrusion, and molding. However, to adapt the starch to specific functionalities chemical modifications or blending with synthetic polymers, such as polycaprolactone are required (e.g. Mater-Bi). As an alternative, all-natural and compostable bio-plastics can be produced by blending starch with other polysaccharides. In this study, we used a maize starch (ST) and an oat β-glucan (BG) composite system to produce bio-plastic prototype films. To optimize performing conditions, we investigated the full range of ST:BG ratios for the casting (100:0, 75:25, 50:50, 25:75 and 0:100 BG). The plasticizer used was glycerol. Electron Paramagnetic Resonance (EPR), using TEMPO (2,2,6,6-tetramethylpiperidine-1-oxyl) as a spin probe, showed that the composite films with high BG content had a flexible chemical environment. They showed decreased brittleness and improved cohesiveness with high stress and strain values at the break. Wide-angle X-ray diffraction displayed a decrease in crystallinity at high BG content. Our data show that the blending of starch with other natural polysaccharides is a noteworthy path to improve the functionality of all-natural polysaccharide bio-plastics systems.
谷物多糖是下一代先进环保塑料的潜在有价值原料。热塑性淀粉（TPS）是使用常规塑料技术加工的，例如铸造、挤出和成型。然而，为了使淀粉适应特定的功能，需要对其进行化学修饰或与合成聚合物（如聚己内酯）共混（例如 Mater-Bi）。作为替代方案，可以通过将淀粉与其他多糖共混来生产全天然可堆肥的生物塑料。在这项研究中，我们使用玉米淀粉（ST）和燕麦β-葡聚糖（BG）复合体系来生产生物塑料原型薄膜。为了优化性能条件，我们研究了铸造过程中 ST:BG 比例的全范围（100:0、75:25、50:50、25:75 和 0:100 BG）。使用的增塑剂是甘油。电子顺磁共振（EPR）使用 TEMPO（2,2,6,6-四甲基哌啶-1-氧自由基）作为自旋探针，表明具有高 BG 含量的复合膜具有灵活的化学环境。它们具有较低的脆性，并在断裂时表现出较高的应力和应变值，从而提高了内聚性。广角 X 射线衍射显示，随着 BG 含量的增加，结晶度降低。我们的数据表明，将淀粉与其他天然多糖共混是提高全天然多糖生物塑料系统功能的一种值得注意的途径。
