In order to improve the comprehensive performance of cross-linked carboxymethyl starch (CCMS)/polyvinyl alcohol (PVA) composite films, expand its application in the field of daily packaging. The CCMS/PVA blend films were prepared by solution casting method. The effect of environmentally friendly non-toxic additives citric acid, urea, CaCl₂, and nano-SiO₂ on the microscopic surface morphology, crystallization properties, thermal properties, mechanical properties, water resistance and optical properties of the CCMS/PVA composite films were investigated. The biocomposite films were characterized by SEM, FT-IR, XRD, TGA, tensile testing, water absorption test, water vapor transmission test, and UV–visible spectrophotometer. The result indicates that the compound addition of citric acid and urea greatly increase the elongation at break of the composite films from 9.2% to 225.7%. With the composite addition of citric acid and nano-SiO₂, the composite film has the best water resistance and water vapor barrier properties. The composite films added with citric acid, urea and nano-SiO₂ can obtain the best thermal stability. Among these four additives, CaCl₂ has the largest negative effect on the elongation at break and urea has the largest negative effect on water resistance properties of the CCMS/PVA composites. The CCMS/PVA composite films prepared by adding 30% citric acid and 6% nano-SiO₂ has the best comprehensive performance. The tensile strength, elongation at break, solubility, thermal decomposition temperature, water vapor permeability and light transmittance of the CCMS/PVA/CA/S composite films are 3.3 MPa, 168%, 34.6%, 293.2°C, 1.54 × 10⁻¹¹ g s⁻¹ m⁻¹ Pa⁻¹ and 22.47%, respectively. The biocomposite film has the potential to be applied in the field of packaging, and provides a reference for further research.

中文翻译：

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添加剂对交联羧甲基淀粉/聚乙烯醇复合薄膜性能的影响

为提高交联羧甲基淀粉（CCMS）/聚乙烯醇（PVA）复合薄膜的综合性能，扩大其在日用包装领域的应用。CCMS/PVA 共混薄膜采用溶液浇铸法制备。环保无毒添加剂柠檬酸、尿素、CaCl ₂和纳米SiO _{2 的作用}对CCMS/PVA复合薄膜的微观表面形貌、结晶性能、热性能、力学性能、耐水性和光学性能进行了研究。通过SEM、FT-IR、XRD、TGA、拉伸试验、吸水率试验、水蒸气透过率试验和紫外-可见分光光度计对生物复合膜进行了表征。结果表明，柠檬酸和尿素的复合添加使复合膜的断裂伸长率从9.2%提高到225.7%。柠檬酸和纳米SiO ₂的复合添加使复合膜具有最佳的耐水性和水蒸气阻隔性能。添加柠檬酸、尿素和纳米SiO ₂的复合薄膜可以获得最佳的热稳定性。在这四种添加剂中，CaCl ₂对断裂伸长率的负面影响最大，尿素对 CCMS/PVA 复合材料的耐水性的负面影响最大。添加30%柠檬酸和6%纳米SiO ₂制备的CCMS/PVA复合薄膜综合性能最好。CCMS/PVA/CA/S复合薄膜的拉伸强度、断裂伸长率、溶解度、热分解温度、透湿性和透光率分别为3.3 MPa、168%、34.6%、293.2℃、1.54×10 ^-11  gs ^-1  m ^-1  Pa ^-1和 22.47%，分别。该生物复合膜在包装领域具有应用潜力，为进一步研究提供参考。