壳聚糖应用于纸张阻隔性涂布的研究

Study on the Application of Chitosan in Paper Barrier Coating

使用壳聚糖溶液对纸张进行涂布,研究了不同涂布量下纸张表面孔隙的封闭程度及涂布纸的阻氧性能与阻湿性能,探讨了壳聚糖/PVDC(聚偏二氯乙烯)复合涂布对涂布纸阻湿性能的改善情况。结果表明,涂布0.46 g/m2壳聚糖能够将纸张表面原有孔隙填满,进一步增大壳聚糖涂布量,纸张表面完全被壳聚糖膜层覆盖,平整程度提高。壳聚糖涂布能够显著提高纸张的阻氧性能,当壳聚糖单层涂布量为1.96 g/m2时,涂布纸的氧气透过率相对原纸至少下降了99.3%,但水蒸气透过率相对原纸有所上升。使用壳聚糖/PVDC复合涂布时,在1.96 g/m2壳聚糖涂层基础上二次涂布7.40 g/m2 PVDC,水蒸气透过率相对单独涂布壳聚糖下降了66.3%,降至原纸的44.8%,与此同时,阻氧性能及表面抗水性均有较大提升。

Chitosan was applied in paper barrier coating. The closed degrees of pore volume as well as oxygen barrier and moisture barrier properties under different coating weights were studied. Meanwhile, to improve moisture barrier properties with hi-layer composites of chitosan/PVDC was discussed. The results showed that the original pores in base paper can be filled up at 0.46 g/m2 chitosan coating weight. With the coating weight increasing, the surface of base paper is completely covered with chitosan film. The oxygen transmission rate （OTR） decreases by 99.3% at least compared with the base paper when coating weight is 1.96 g/m^2, while water vapor transmission rate （WVTR） increases slightly. As for chitosan/PVDC composite coating, the WVTR decreases by 66.3% compared with the chitosan coated paper, and decreases to 44.8% compared to base paper when PVDC （7.40 g/m^2 ） is coated on the chitosan coated paper （ 1.96 g/m^2 ）. The oxygen barrier property as well as surface resistance to water have enormous improvement at the same time.