Lou Jiangfei, Dong Aixue, Hu Lingling
Key Laboratory of Clean Dyeing and Finishing Technology of Zhejiang Province, Shaoxing University, Shaoxing, 312000, Zhejiang, China.
College of Textile Science and Engineering, Shaoxing University, Shaoxing, 312000, Zhejiang, China.
Appl Biochem Biotechnol. 2025 Jun 28. doi: 10.1007/s12010-025-05321-1.
Copolymer membranes based on polyvinyl alcohol (PVA) and starch suffer from low mechanical strength and poor fresh-produce preservation and degradation performance. Adding functional cellulose or derivatives to membranes can improve these properties. Herein, free radical grafting polymerization between microcrystalline cellulose (MCC) and catechol (CA) was performed using a horseradish peroxidase (HRP)/acetylacetone/HO system, and the product was incorporated into a PVA/Starch membrane to improve its performance. The MCC-CA polymer was structurally characterized by FTIR, H NMR, C NMR, XRD, and HPLC methods. The covalent binding mechanism during the free radical polymerization process was analyzed and optimized based on HRP enzyme dosage, HO dosage, CA dosage, reaction temperature, and reaction duration. The mechanical properties, antioxidant properties, degradation properties, and freshness properties of the Starch/MCC-CA membrane were explored. The results indicated MCC and CA were graft polymers between free radicals; the Starch/MCC-CA membrane had a significant improvement in degradation, free radical scavenging properties, and mechanical properties, with the freshness of bananas maintained for > 10 days, superior to existing commercially available PVA/Starch preservation membranes.
基于聚乙烯醇（PVA）和淀粉的共聚物膜存在机械强度低、新鲜农产品保鲜和降解性能差的问题。向膜中添加功能性纤维素或其衍生物可以改善这些性能。在此，使用辣根过氧化物酶（HRP）/乙酰丙酮/H₂O₂体系进行微晶纤维素（MCC）和邻苯二酚（CA）之间的自由基接枝聚合，并将产物掺入PVA/淀粉膜中以改善其性能。通过傅里叶变换红外光谱（FTIR）、¹H核磁共振（¹H NMR）、¹³C核磁共振（¹³C NMR）、X射线衍射（XRD）和高效液相色谱（HPLC）方法对MCC-CA聚合物进行结构表征。基于HRP酶用量、H₂O₂用量、CA用量、反应温度和反应持续时间，分析并优化了自由基聚合过程中的共价结合机制。探索了淀粉/MCC-CA膜的机械性能、抗氧化性能、降解性能和保鲜性能。结果表明，MCC和CA是自由基之间的接枝聚合物；淀粉/MCC-CA膜在降解、自由基清除性能和机械性能方面有显著改善，香蕉的保鲜期超过10天，优于现有的市售PVA/淀粉保鲜膜。
