耿延训,褚彩玲,徐化能

• 1:江南大学 食品学院， 江苏 无锡 214122

摘要(Abstract)：

通过以甲基纤维素（MC）与乙酰化纳米纤维素（ACNF）复合制备水凝胶，利用傅里叶红外光谱、流变仪、激光共聚焦显微镜等考察了MC与ACNF分子间作用力以及不同相对分子质量MC在ACNF临界凝胶质量分数附近对复合水凝胶微观结构与动态流变性质的影响。结果表明，复合凝胶通过氢键、范德华力及疏水作用等形成网络结构，ACNF临界凝胶质量分数为2%~3%；当ACNF质量分数为2%时，MC能提供更多的交联点促进凝胶三维网络结构的形成（桥连作用），表现为黏弹性模量与线性黏弹性区应变值均随着MC相对分子质量的增加而增加；当ACNF质量分数为3%时，MC能强化已有凝胶网络结构特征（填充作用），表现为黏弹性模量随着MC相对分子质量的增加而增加、线性黏弹性区应变值几乎保持不变。温度升高会改变体系氢键与疏水作用的占比，从而改变复合凝胶的流变性能。

关键词(KeyWords)： 乙酰化纳米纤维素纤维;甲基纤维素;流变;水凝胶

Abstract:

Keywords:

基金项目(Foundation): 国家自然科学基金（21576116）。

作者(Author): 耿延训,褚彩玲,徐化能

DOI: 10.3969/j.issn.1003-9015.2020.01.029

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