College of Chemistry and Materials Engineering, National Engineering & Technology Research Center of Wood-Based Resources Comprehensive Utilization, Zhejiang A & F University, Hangzhou 311300, China.
Institute of Chemical Industry of Forest Products, Chinese Academy of Forestry, Jiangsu Province Key Laboratory of Biomass Energy and Materials, Nanjing 210042, China.
Int J Biol Macromol. 2024 Sep;276(Pt 1):133746. doi: 10.1016/j.ijbiomac.2024.133746. Epub 2024 Jul 14.
Pectin, a polysaccharide found in plant cell walls, is characterized by a high abundance of hydroxyl groups and carboxylic acid groups, which results in a strong affinity for water and limits its suitability as a film material. This study aimed to modulate the esterification degree of PEC films by adjusting the concentration of acetic anhydride, and assess the impact of acetic anhydride esterification modification on the properties of the resultant PEC films. The results demonstrated successful grafting of acetic anhydride onto the galacturonic acid ring in the PEC molecule through the esterification process. The hydrophobicity, thermal stability, barrier properties, and mechanical properties of the esterified PEC films were investigated. Among the various concentrations tested, the E-PEC-0.25 film exhibited the highest contact angle of 103.46° and tensile strength of 33.44 MPa, showcasing optimal performance. The E-PEC-0.1 film achieved the highest esterification degree of 0.94 and elongation at a break of 21.11 %. It also exhibited the transparency of 11.66 and the lowest water vapor transmission rate of 0.56 g·mm/(m·h·kpa). Additionally, TGA and DSC tests revealed enhanced thermal stability of the esterification-prepared films. These findings highlight the potential of acetic anhydride tuning as a promising strategy for optimizing pectin film production.
果胶是一种存在于植物细胞壁中的多糖，其特点是羟基和羧基含量丰富，这导致其对水具有很强的亲和力，限制了其作为成膜材料的适用性。本研究旨在通过调整乙酸酐的浓度来调节 PEC 膜的酯化程度，并评估乙酸酐酯化修饰对所得 PEC 膜性能的影响。结果表明，通过酯化过程成功地将乙酸酐接枝到 PEC 分子的半乳糖醛酸环上。研究了酯化 PEC 膜的疏水性、热稳定性、阻隔性能和机械性能。在所测试的各种浓度中，E-PEC-0.25 膜表现出最高的接触角 103.46°和拉伸强度 33.44 MPa，表现出最佳性能。E-PEC-0.1 膜达到了最高的酯化度 0.94 和断裂伸长率 21.11%。它还表现出 11.66%的透光率和 0.56 g·mm/(m·h·kpa)的最低水蒸气透过率。此外，TGA 和 DSC 测试表明酯化制备的薄膜具有增强的热稳定性。这些发现强调了通过乙酸酐调谐优化果胶膜生产的潜力。
