PBAT/PVA复合涂布膜阻隔性研究

Barrier Property of PBAT/PVA Composite Coating Film

目的为改善PBAT膜的阻隔性,通过以戊二酸为交联剂改性PVA制备涂膜液,利用涂布法制备了具有高阻隔性的PBAT/PVA复合薄膜。方法采用红外光谱、差示扫描量热仪、接触角测试仪、水蒸气透过率测试仪等对改性PVA单膜、PBAT/PVA复合膜的结构和性能进行研究。结果表明由于戊二酸与PVA之间有一定的酯化作用,消耗PVA中部分羟基,从而提高了PVA的耐水性。戊二酸改性提高了PVA膜的疏水性,其接触角从11.3°提高到60.6°。与PBAT纯膜相比,涂覆了戊二酸的PVA涂膜液改性3 h后复合膜水蒸气透过率由647.95 g/(m^(2)·24 h)降低到132.07 g/(m^(2)·24 h)、氧气透过量由17730.3 cm^(3)/(m^(2)·d·MPa)降低到396.6 cm^(3)/(m^(2)·d·MPa),证明改性3 h的PVA涂膜液对增加PBAT阻隔性最有帮助。结论利用涂布法制备的PBAT/PVA复合薄膜具有较高阻隔性,为PBAT的广泛应用打下了基础。

The work aims to improve the barrier properties of PBAT film,prepare coating film with glutaric acid as a crosslinking agent modified PVA and prepare PBAT/PVA composite film with high barrier properties by coating method.Infrared spectroscopy,differential scanning calorimeter,contact angle tester,water vapor transmission rate tester,etc.were used to study the structure and performance of modified PVA mono film and PBAT/PVA composite film.The results showed that glutaric acid had a certain esterification effect with PVA,which consumed part of the hydroxyl groups in PVA,thereby improving the water resistance of PVA.Glutaric acid modification improved the hydrophobicity of the PVA film,and its contact angle increased from 11.3°to 60.6°.Compared with the pure PBAT film,the water vapor transmission rate of the composite film modified by glutaric acid for 3 h was reduced from 647.95 g/(m^(2)·24 h)to 132.07 g/(m^(2)·24 h),and the oxygen transmission rate was reduced from 17730.3 cm^(3)/(m^(2)·d·MPa)to 396.6 cm^(3)/(m^(2)·d·MPa),which proved that the PVA coating liquid modified for 3 h was most helpful to increase the PBAT barrier properties.The PBAT/PVA composite film prepared by coating method has high barrier property,which lays a foundation for the wide application of PBAT.