氨基功能化纳米纤维素气凝胶的制备及性能

Preparation and characterization of 3-(2-aminoethylamino) propylmethyldimethoxysilane-nano cellulose aerogels

选用3-(2-氨基乙氨基)丙基甲基二甲氧基硅烷(AEAPMDS)对球形纤维素纳米纤维(CNF)湿凝胶进行化学修饰,探讨了改性反应条件对氨基纳米纤维素中N含量的影响,选用叔丁醇溶液为置换溶剂,采用冷冻干燥制备了一种新型的生物质气凝胶。对所制备的3-(2-氨基乙氨基)丙基甲基二甲氧基硅烷-纤维素纳米纤维(AEAPMDS-CNF)气凝胶的微观形貌、结构特征、力学强度及CO2的吸附等性能进行表征和分析。结果表明:反应时间为10h、反应温度为90℃、AEAPMDS溶液的质量分数为12wt%时,是AEAPMDS-CNF气凝胶的最佳制备方案。改性后的纤维素气凝胶具有三维网络孔结构、质轻(ρ≤0.0573g·cm-3)、高孔隙率(ε>90%)等特点,其压缩强度为0.46MPa,CO2吸附量高达1.54mmol·g-1,表现出优异的CO2吸附性能,具有很大的应用前景。

A novel cellulose nanofibers（CNF）aerogels were prepared based on the spherical cellulose nanofiber gel modified with 3-（2-aminoethylamino）propylmethyldimethoxysilane（AEAPMDS）in combination by solvent displacement and freeze drying.The change of its N content was investigated under different reaction conditions.The resultant spherical nano cellulose aerogels were characterized with respect to microscopic morphology,structural characteristics,mechanical properties and CO2 adsorption properties.The results show that the best preparation condition of the AEAPMDS-CNF aerogel is for 10 hat 90℃ and 12 wt% AEAPMDS.The prepared AEAPMDSCNF aerogel is a mesoporous material with 3 Dnetwork pore structure,light mass（ρ≤0.0573 g·cm-3）and high porosity（ε〉90%）.Its compressive strength can reach 0.46 MPa with a high CO2 adsorption capacity of up to 1.54 mmol·g-1.It is a promising material for CO2 adsorption in the future.