海藻酸钠-果胶改性复合膜的制备及表征

Preparation and characterization of cross-linking composite films based on sodium alginate and pomelo pectin

以海藻酸钠(SA)和柚皮果胶(PEC)为基材,辅以添加甘油和不同种类脂质制备复合膜,通过分析各组分对膜水蒸气透过系数、过氧化值、抗拉强度等指标的影响,确定复合膜的适宜配方:SA与PEC的质量比为10/2,甘油的添加量0.3%,石蜡添加量为0.12%。以CaCl_2、BaCl_2、FeCl_3、Al_2(SO_4)_3不同交联剂对该复合膜进行改性,以CaCl_2为交联剂,CaCl_2浓度3%、交联时间3min条件下制备的海藻酸钠-果胶改性复合膜各项性能提高。以FTIR、SEM、XRD、接触角测定膜的表面结构形态和性质进行表征和测试。研究结果表明海藻酸钠-果胶复合膜各组分间的相容性好,经CaCl_2交联后显著改善膜的阻隔性能、机械性能及抗水性能,海藻酸钠-果胶改性复合膜是一种具有良好发展前景的可降解复合包装膜。

The optimization of the composite films formula which using sodium alginate and pomelo pectin as basic materials,glycerol and different kinds of lipids was studied. The property such as tensile strength,fracture strain,and water vapor were studied. The optimal formula was ：SA-PEC mass ratio 10/2,glycerol 0.3%,and paraffin wax 0.12%. The composite membrane was cross-linked with CaCl2、BaCl2、FeCl3 and Al2（SO4）3. When CaCl2 3%,crosslinking time 3 min,the performance of SA-PEC composite film increased. Composite film was characterized by FTIR,SEM,XRD and the contact angle. The experiment results showed that SA-PEC composite film had good compatibility between different components,and crosslinking with CaCl2 could improve the barrier property,mechanical property and water resistance of the membrane significantly. SA-PEC modified composite membrane is a degradable composite packaging film and has a with a great potential.