Origin of hydrophilicity of cellulose hydrogel from aqueous LiOH/urea solvent coagulated with alkyl alcohols
Origin of hydrophilicity of cellulose hydrogel from aqueous LiOH/urea solvent coagulated with alkyl alcohols
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DOI：
10.1007/s10570-013-0080-7
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发表时间：
2014-04
期刊：
影响因子：
5.7
通讯作者：
Noriyuki Isobe;Y. Nishiyama;S. Kimura;M. Wada;S. Kuga
中科院分区：
文献类型：
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作者：
Noriyuki Isobe;Y. Nishiyama;S. Kimura;M. Wada;S. Kuga
研究了乙醇混凝法制备的LiOH/尿素纤维素水凝胶的表面和结构性能。采用甲醇-丁醇醇作为混凝剂。具有高水混相的醇（MeOH, EtOH, 1-PrOH, 2-PrOH，和t- buoh）形成了由纤维素纤维网络组成的纳米多孔结构，而具有低水混相的醇（1-BuOH, 2-BuOH,i-BuOH）由于在凝聚过程中收缩大，呈现出纤维结构的聚集。刚果红吸附测定表明，醇碳数的增加使表面疏水性降低。这很可能发生，因为在乙醇、丙醇和丁醇的混凝过程中形成了碱/尿素/纤维素复合物，导致纤维素II的结晶含量更高，其表面被认为是高度亲水的。
Surface and structural properties of cellulose hydrogel prepared from LiOH/urea solvent with alcoholic coagulation were examined. As coagulants, alcohols from methanol to butanol were employed. Alcohol with high water miscibility (MeOH, EtOH, 1-PrOH, 2-PrOH, andt-BuOH) gave a nano-porous structure consisting of a fibrous network of cellulose, while alcohol with low water miscibility (1-BuOH, 2-BuOH,i-BuOH) showed aggregation of a fibrous structure because of large shrinkage during the coagulation process. Congo red adsorption measurement showed that an increase in the carbon number of alcohol brought about a less hydrophobic surface. This is likely to occur because the alkali/urea/cellulose complex was formed during the coagulation process in the case of ethanol, propanol, and butanol, leading to a higher crystalline content of cellulose II, the surface of which is thought to be highly hydrophilic.