壳聚糖/AKD乳液改善纸浆模塑制品防水防油性能的研究

Improving Water and Oil Resistance of Pulp Molded Products by Chitosan/AKD Emulsion

中文关键词: 壳聚糖  烷基烯酮二聚物(AKD)  防水防油助剂  纸浆模塑

英文关键词: chitosan  alkyl ketene dimmer (akd)  water- and oil-proof additive  pulp molded products

中文摘要:

      目的 以壳聚糖/AKD乳液替代传统的AKD乳液，作为安全无毒的防水防油剂，以改善纸浆模塑的防水防油性能。方法 采用壳聚糖作为乳化剂，在高剪切分散乳化条件下与AKD蜡共混，获得稳定均一的壳聚糖/AKD乳液，然后通过浆内施胶的方式制备纸浆模塑制品，对纤维的滤水性能、纸浆模塑制品的力学性能以及防水防油性能进行研究。结果 以壳聚糖质量分数为1.5%的壳聚糖醋酸溶液，可制备得到AKD蜡质量分数为5%的乳白色壳聚糖/AKD乳液;乳液的添加未影响纤维的滤水性能，且当其用量占绝干浆质量的7%时，纤维悬浮液的打浆度和保水值分别达到23 °SR和(1.71±0.06)g/g，满足生产要求。对比未添加乳液的样品，添加了质量分数为7%的乳液后，纸浆模塑制品的力学性能，包括紧度、抗张强度、耐破指数和撕裂强度分别提高了26.2%、60.6%、152.6%和67.1%，Cobb60值降低到了(18.5±0.68)g/m²，静态水接触角提高到了(119±4.1)°，体现防油性能的Kit值提高到了第8等级，油接触角提高到了(97.9±3.1)°。纸浆模塑制品具有良好的防热水和防热油的性能。结论 壳聚糖/AKD乳液可作为一种新型防水防油助剂用于纸浆模塑制品生产，拓展了环保造纸助剂品类。

英文摘要:

      The work aims to prepare Chitosan/AKD emulsion to replace the traditional AKD emulsion and use it as a non-toxic water- and oil-proof agent to improve the water and oil resistance of pulp molded products. Chitosan was used as an emulsifier, blended with AKD wax under high shear emulsification. The process parameters of stable and uniform chitosan/AKD emulsion were studied, and pulp molded products were prepared by internal sizing. The mechanical strength, as well as the water and oil resistance of finished products were investigated. When using a chitosan acetic acid solution with a chitosan concentration of 1.5 wt%, a milky white chitosan/AKD emulsion with a AKD concentration of 5 wt% was obtained. The addition of chitosan/AKD emulsion did not affect the water drainage performance of the pulp fibers. When the dosage of chitosan/AKD emulsion accounted for 7 wt% of the absolute dry pulp, the beating degree and water retention value of the pulp suspension were respectively 23 °SR and (1.71±0.06) g/g, meeting the production requirements of pulp molded products. Compared with the control sample without chitosan/AKD emulsion, when the addition amount was 7 wt%, the mechanical properties of pulp molded products include tightness, tensile strength, bursting index and tear strength increased by 26.2%, 60.6%, 152.6% and 67.1% respectively. The Cobb60 value and static water contact angle reflecting waterproof performance were reduced or increased to (18.5±0.68) g/m2 and (119±4.1)°. The Kit value reflecting the oil-proof performance was increased to level 8, and the oil contact angle was increased to (97.9±3.1)°. It also has excellent resistance to hot water and hot oil. In conclusion, chitosan/AKD emulsion can be used as a new water- and oil-proof additive in production of pulp molded products, expanding the category of environmentally friendly and degradable paper-making additives.