有机酸改性聚乙烯醇涂布对纸张阻隔性能影响

Effect of Organic Acid Modified Polyvinyl Alcohol Coating on the Barrier Properties of Paper

关键词:  聚乙烯醇  纸基材料  琥珀酸  柠檬酸  阻隔性能

Key Words:polyvinyl alcohol  paper-based material  succinic acid  citric acid  barrier properties

摘要:为了提高聚乙烯醇（PVA）涂布纸张的阻隔性能，采用琥珀酸（SA）、柠檬酸（CA）或二者协同策略对PVA化学改性，探究了有机酸改性PVA涂布对纸张防水、防油和水蒸气阻隔性能的影响。结果表明，有机酸改性PVA的溶胀度明显下降，其中SA与CA协同改性PVA（PVA-SC）的溶胀度下降最大，为未改性PVA的14%；当涂布量为5.0 g/m²时，相较于未改性PVA，PVA-SC涂布纸Cobb₆₀值下降约50%，水蒸气透过率下降90%；有机酸改性PVA和未改性PVA均具有优异的防油性能。在改性或未改性PVA涂布液中添加AKD乳液，涂布后纸张表面自由能大幅下降，接触角增大，疏水性增强。

Abstract:In order to improve the barrier properties of polyvinyl alcohol （PVA） coated paper， succinic acid （SA）， citric acid （CA）， or SA and CA synergistic strategies were used to chemically modify PVA. The effects of organic acid modified PVA coating on the waterproof， oil proof， and water vapor resistance of paper were investigated. The results showed that the swelling degree of organic acid modified PVA decreased significantly， with SA and CA co-modified PVA （PVA-SC） showing the greatest decrease in swelling degree， which was 14% of unmodified PVA. When the coating amount was 5.0 g/m²， compared to unmodified PVA， the Cobb₆₀ value of the PVA-SC coated paper decreased by about 50% and the water vapor transmission rate decreased by 90%. Organic acid modified PVA had excellent oil resistance， just like unmodified PVA. Addition of AKD dispersion to modified or unmodified PVA coating solution resulted in a significant decrease in the surface free energy of the coated paper， an increase in the contact angle and hydrophobicity.