以纖維素/AmimCl溶液制備纖維素氣凝膠(Cellulose aerogels prepared from cellulose/AmimCl solutions)
作者：呂玉霞, 李小艷, 米勤勇, 王德修, 余堅,* 張軍*
關(guān)鍵字：纖維素, AmimCl 離子液體, 氣凝膠, 超臨界CO2, 凝固浴
論文來源：期刊
具體來源：中國科學: 化學, 2011, 41(8): 1331-1337.
發(fā)表時間：2011年
利用離子液體AmimCl 溶解結(jié)合超臨界CO2 干燥的方法制備了纖維素氣凝膠材料.研究了不同初始濃度的纖維素溶液及其在不同凝固浴中制備的纖維素凝膠的流變行為, 進一步考察了纖維素溶液濃度和凝固浴種類對纖維素氣凝膠材料結(jié)構(gòu)的影響. 結(jié)果表明, 隨著初始纖維素溶液濃度的增大, 氣凝膠的孔結(jié)構(gòu)逐漸致密, 比表面積隨之減小; 凝固浴的組成對纖維素氣凝膠的結(jié)構(gòu)也有較大影響. 采用適當?shù)闹苽錀l件, 可以制備出高比表面積的纖維素氣凝膠材料. 對纖維素氣凝膠的熱性能進行了表征, 結(jié)果表明所得到的氣凝膠材料具有較好的熱穩(wěn)定性和較高的炭殘余含量.
Cellulose aerogel materials were prepared by combining dissolving cellulose in an ionic liquid, 1-allyl-3-methylimidazolium chloride (AmimCl), and drying in supercritical CO2. The rheological properties of the cellulose solutions of different concentrations and their gels regenerated in different coagulation baths were studied. The porous structure and morphology of cellulose aerogels were found to be affected by cellulose concentration and nature of the coagulation bath. With increasing initial cellulose concentration, the porous structure of cellulose aerogels became more dense and uniform, leading to the gradual decrease of the specific surface area. Further, it was also observed that, both viscosity and the polarity of coagulation bath affected the structure of cellulose aerogels. High specific surface areacellulose aerogel materials could be prepared by controlling the experimental conditions. The obtained cellulose aerogels had relatively high char yield at elevated temperature, which makes them potential precursors for fabrication of novel mesoporous carbon materials.