林业工程学报2017，Vol.2Issue(4)：109-114,6.DOI:10.13360/j.issn.2096-1359.2017.04.018
液氮冷冻干燥法制备纳米纤维素气凝胶
Fabrication of nano-cellulose aerogels by drying liquid nitrogen freeze
摘要
Abstract
Cellulose aerogel is known as the third generation of aerogel following organic and inorganic aerogel and has broad applications in the field of adsorption materials.In this paper,sulfuric acid hydrolysis method was adopted to prepare nano-cellulose.The spherical nano-cellulose aerogel prepared with physical gelmolding in inorganic salt solution followed by freeze-dried had large effective adsorption areas.The microstrucmre,specific surface area,mechanical property,pore size distribution as well as the thermal degradation properties of the prepared aerogel were analyzed via scanning electron microscope(SEM),a universal testing machine,a thermo gravietric analyzer and a micrometrics analyzer.The results showed that the microstructure and specific surface areas of cellulose aerogel prepared by freezedrying are mainly of three-dimensional layered structure and a small amount of three-dimensional network.The structures exhibited a specific surface areas ranged from 104.07 to 164.97 m2/g with a pore size of 10-25 nm.The isotherm adsorption-desorption curves for nano-cellulose aerogels were of Type Ⅱ and is given priority to multilayer adsorption.The hysteresis loop in the high pressure of isotherm adsorption-desorption curves indicated that it has abundant pore structure;The pore size distributions of the nano-cellulose aerogel indicated the apertures are majody mesoporous;The mechanical properties,compressive intensity and density of the aerogel increased with the increasing of cellulose concentration.With the increase of fiber mass fraction,the adsorption quantity,specific surface area and porosity of nano-cellulose aerogel increased.The nano-cellulose aerogel showed a similar thermal degradation behavior as those of microcrystalline cellulose(MCC) and nanocrystal cellulose(NCC).关键词
气凝胶/叔丁醇/液氮/冷冻干燥/纳米纤维素Key words
aerogel/tert-butyl alcohol/liquid nitrogen/freeze-drying/nano-cellulose分类
化学化工引用本文复制引用
赵华,张洋,王晓宇,宋宇轩..液氮冷冻干燥法制备纳米纤维素气凝胶[J].林业工程学报,2017,2(4):109-114,6.基金项目
国家林业公益性行业科研专项(201504603). （201504603）
