期刊
POLYMERS
卷 13, 期 8, 页码 -出版社
MDPI
DOI: 10.3390/polym13081241
关键词
cellulose; crystallinity; modification; cellulose esters; structure; hydrophilicity; hydrophobicity parameters; performance properties
The hydrophobicity of cellulose can be significantly increased through acid hydrolysis and esterification. Esterification disrupts the crystalline structure of cellulose, replacing polar hydroxyl groups with non-polar substituents to enhance the hydrophobicity. Increasing the number of non-polar groups in the ester substituent contributes to the rise in hydrophobicity of cellulose derivatives.
In this study, physicochemical and chemical methods of cellulose modification were used to increase the hydrophobicity of this natural semicrystalline biopolymer. It has been shown that acid hydrolysis of the initial cellulose increases its crystallinity, which improves hydrophobicity, but only to a small extent. A more significant hydrophobization effect was observed after chemical modification by esterification, when polar hydroxyl groups of cellulose were replaced by non-polar substituents. The esterification process was accompanied by the disruption of the crystalline structure of cellulose and its transformation into the mesomorphous structure of cellulose esters. It was found that the replacement of cellulose hydroxyls with ester groups leads to a significant increase in the hydrophobicity of the resulting polymer. Moreover, the increase of the number of non-polar groups in the ester substituent contributes to rise in hydrophobicity of cellulose derivative. Depending on the type of ester group, the hydrophobicity increased in the following order: acetate < propionate < butyrate. Therefore, tributyrate cellulose (TBC) demonstrated the most hydrophobicity among all studied samples. In addition, the mixed ester, triacetobutyrate cellulose (TAB), also showed a sufficiently high hydrophobicity. The promising performance properties of hydrophobic cellulose esters, TBC and TAB, were also demonstrated.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据