碱木质素壳聚糖反应膜的制备与性能

Preparation and performance of alkali lignin/chitosan reaction film

以壳聚糖和碱木质素为原料,以戊二醛作交联剂,制备碱木质素/壳聚糖反应膜,并测定薄膜的相关物理性能。研究结果表明,碱木质素/壳聚糖反应膜制备的最佳条件为羟甲基化碱木质素与壳聚糖的质量比为1∶2,加入质量比为0.3%戊二醛溶液作交联剂,0.5%(质量分数)甘油,25℃反应6h后真空脱泡2h得到制膜液,铺膜,于50℃烘干制膜。膜的厚度为12～13μm,抗张力为27～28N,吸水溶胀度为28.4%。羟甲基化碱木质素在壳聚糖膜中的分布较为均匀。羟甲基化碱木质素的羟基或壳聚糖的羟基与戊二醛发生了交联反应。由于碱木质素具有较强的抗酸性能,同时羟甲基化碱木质素抗碱能力高于碱木质素,使碱木质素壳聚糖反应膜在强酸和强碱性溶液中均保持了使用性能。提高了反应膜的抗酸碱性能,适用范围为pH值=1～14时,扩大了膜的使用范围。

With chitosan and alkali lignin as raw materials, glutaraldehyde as cross-linking agent, the alkali lignin/chitosan reaction film was prepared, the physical properties of the films were measured. The results show that the optimum conditions to prepare the alkali lignin/chitosan reaction film are as follows： the mass ratio of hydroxymethylated alkali lignin and chitosan 1 ： 2, the mass fraction of glutaraldehyde solution and glycerol respectively 0.3）/0 and 0.5 %, the reaction tempareture 25℃, the reaction time 6h. The film forming liquid was got after it han been defoamed for 2h in vacuum condition,then layed and dryed at 50℃. The thickness of the film was 12-13/,m and the tensile strength was 27-28N. The degree of swelling was 28.4o/4. The hydroxymeth- ylated alkali lignin was evenly distributed in the chitosan film. The hydroxyl groups of hydroxymethylated alkali lignin or chitosan have a crosslinking reaction with glutaraldehyde. For the alkali lignin has astrong acid resistance and hydroxymethylated alkali lignin has better alkali resistance than the alkali lignin, the alkali lignin / chitosan reaction film maintains the usability in strong acid and strong alkaline solution. The ability of resistance to acid and alkali of the reaction film was improved . Scope of application of pH was 1 to 14 wich expands the range of application of the film.