Huang Ling-Jie, Lee Wen-Jau, Chen Yi-Chun
Department of Forestry, National Chung-Hsing University, 145 Xingda Rd., South Dist., Taichung City 402, Taiwan.
Polymers (Basel). 2022 Jan 5;14(1):204. doi: 10.3390/polym14010204.
Hydrogel composites can be prepared from cellulose-based materials and other gel materials, thus combining the advantages of both kinds of material. The aerogel, porous material formed after removing the water in the hydrogel, can maintain the network structure. Hydrogel and aerogel have high application potential. However, low mechanical strength and weight loss of cellulose hydrogel due to the water dehydration/absorption limit the feasibility of repeated use. In this study, cellulose hydrogels were prepared using microcrystalline cellulose (MC), carboxymethyl cellulose (CMC), and hydroxyethyl cellulose (HEC) as raw materials. Waterborne polyurethane (WPU) was added during the preparation process to form cellulose/WPU composite hydrogel and aerogel. The influence of the cellulose type and WPU addition ratio on the performance of hydrogel and aerogel were investigated. The results show that the introduction of WPU can help strengthen and stabilize the structure of cellulose hydrogel, reduce weight loss caused by water absorption and dehydration, and improve its reusability. The mixing of cellulose and WPU at a weight ratio of 90/10 is the best ratio to make the cellulose/WPU composite aerogel with the highest water swelling capacity and heat resistance.
水凝胶复合材料可以由纤维素基材料和其他凝胶材料制备而成，从而兼具这两种材料的优点。气凝胶是水凝胶中的水分去除后形成的多孔材料，能够保持网络结构。水凝胶和气凝胶具有很高的应用潜力。然而，纤维素水凝胶由于水的脱水/吸水导致机械强度低和重量损失，限制了其重复使用的可行性。在本研究中，以微晶纤维素（MC）、羧甲基纤维素（CMC）和羟乙基纤维素（HEC）为原料制备纤维素水凝胶。在制备过程中添加水性聚氨酯（WPU），以形成纤维素/WPU复合水凝胶和气凝胶。研究了纤维素类型和WPU添加比例对水凝胶和气凝胶性能的影响。结果表明，WPU的引入有助于增强和稳定纤维素水凝胶的结构，减少吸水和脱水引起的重量损失，并提高其可重复使用性。纤维素与WPU以90/10的重量比混合是制备具有最高水溶胀能力和耐热性的纤维素/WPU复合气凝胶的最佳比例。
