The development of sustainable materials has driven significant interest in starch as a renewable and biodegradable polymer. However, the inherent brittleness, hydrophilicity, and lack of thermoplasticity of native starch limit its application in material science. This study addresses the limitations of native starch by converting it to dialdehyde starch (DAS) and cross-linking with polyether diamines via imine bonds. The effects of Jeffamine molecular weights (D-2000, D-400, and D-230) and mole ratios on the mechanical, thermal, and structural properties of starch-based films were examined. The cross-linked DAS/Js films exhibited significant enhancements in flexibility and toughness. Specifically, DAS/J2000 at a 0.03 mol ratio achieved a tensile strength of 62.9 MPa. In comparison, DAS/J400 at a 0.5 mol ratio demonstrated 126.2% elongation at break, indicating the balance between cross-linking density and chain mobility. X-ray diffraction (XRD) analysis revealed reduced crystallinity and tighter molecular packing with increased cross-linking. Dynamic mechanical analysis (DMA) indicated a decrease in Tg with an increasing mole ratio, reflecting enhanced molecular mobility. The results underscore the potential of optimized cross-linking conditions to produce starch-based films with properties that contribute to developing sustainable biopolymer materials.

可持续材料的发展激发了人们对淀粉作为可再生和生物降解聚合物的兴趣。然而，天然淀粉固有的脆性、亲水性和缺乏热塑性限制了它在材料科学中的应用。本研究通过将天然淀粉转化为双醛淀粉（DAS）并通过亚胺键与聚醚二胺交联来解决天然淀粉的这些局限性。研究考察了杰法米（Jeffamine）分子量（D-2000、D-400 和 D-230）和摩尔比对基于淀粉薄膜的机械、热学和结构性能的影响。交联的DAS/Js 薄膜在柔韧性和韧性方面表现出显著增强。具体而言，当摩尔比为 0.03 时，DAS/J2000 达到了 62.9 MPa 的拉伸强度。相比之下，当摩尔比为 0.5 时，DAS/J400 表现出 126.2% 的断裂延伸率，表明交联密度和链段移动性的平衡。X 射线衍射（XRD）分析显示随着交联增加结晶度降低且分子堆积更紧密。动态力学分析（DMA）结果显示 Tg 随摩尔比的增加而减小，反映了分子运动性的增强。结果强调了通过优化交联条件来生产具有贡献于开发可持续生物聚合物材料性能的基于淀粉薄膜的潜力。