【摘 要】
：
Cellulose dissolved in 8% LiCl/dimethyl sulfoxide (LiCl/DMSO) via ethylenediamine (EDA) pretreatment was found to undergo reaction with tetraethyl orthosili
【机 构】
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Jiangsu Provincial Key Lab of Biomass-based Green Fuel & Chemicals, College of Chemical Engineering,
论文部分内容阅读
Cellulose dissolved in 8% LiCl/dimethyl sulfoxide (LiCl/DMSO) via ethylenediamine (EDA) pretreatment was found to undergo reaction with tetraethyl orthosilicate (TEOS) at room temperature, forming transparent gels.This phenomenon apparently showed the TEOS undergo ester exchange with cellulose, and the multivalency of TEOS gave rise to crosslinking of dissolved cellulose.Several aspects of behavior of this system were consistent with this interpretation.The presence of trace EDA, arising from cellulose pretreatment, was essential for the reaction, probably acting as catalyst.Cellulose-silicate composite aerogels were prepared from these transparent gels after solvent exchange with ethanol followed by tert-butanol and freeze-drying.The aerogels were investigated by SEM, EDX and BET analysis (nitrogen gas adsorption).
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