氨基功能化纳米纤维素气凝胶的制备及性能

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10 h、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 ≤ 0.0573 g·cm^-3）、高孔隙率（ε>90%）等特点，其压缩强度为0.46 MPa，CO₂吸附量高达1.54 mmol·g^-1，表现出优异的CO₂吸附性能，具有很大的应用前景。

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

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 h at 90℃ and 12wt% AEAPMDS. The prepared AEAPMDS-CNF aerogel is a mesoporous material with 3D network 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.