冻融法构建超疏水纤维素/壳聚糖气凝胶及其吸油性能

Construction of Cellulose/Chitosan Super-Hydrophobic Aerogel by Freeze-Thaw Method and Its Oil Absorption Performance

以微晶纤维素、壳聚糖为双网络单元,以氢氧化钠/尿素/水为溶剂体系、甲基三甲氧基硅烷(MTMS)为改性剂,采用“冻融-浸渍”两步法制得超疏水纤维素/壳聚糖复合气凝胶。研究结果表明,该复合气凝胶呈现三维互穿多孔结构,其接触角随着MTMS的加入,先逐渐增大后急剧减小,当MTMS的浓度为1.96 g/μL时,疏水效果最好,接触角可达到151°。此外,该气凝胶具有良好的油/水选择性吸收能力,吸油量最高达到9.3 g/g,且经过5次再生循环后,对于异丙醇的吸附量仍能保持初始值的92.8%,是一种良性可再生的生物质基吸油材料。

Herein,a kind of super-hydrophobic cellulose/chitosan hybrid aerogel was prepared via“freeze-thaw-impregnation”two-step method,in which cellulose and chitosan worked as double network units with sodium hydroxide/urea/water as solvent system and methyl trimethoxysilane(MTMS)acted as modifier.A series of characterizations show that the hybrid aerogel presents a three-dimensional interpenetrating porous structure,and the contact angle gradually raises first and then decreases sharply with the incorporation of MTMS.When the concentration of MTMS is 1.96 g/μL,the hydrophobic effect reaches the optimal with the contact angle of 151°.In addition,the aerogel displays good oil/water selective absorption performance with the maxmium oil absorption capacity of 9.3 g/g.After the 5th regeneration,the adsorption capacity for isopropyl alcohol can still maintain 92.8%of its initial value,indicating a benign and renewable biomass-based oil absorption material.