李英豪,耿延训,徐化能

• 1:江南大学 食品学院，江苏 无锡 214122

摘要(Abstract)：

纳米纤维素纤维（cellulosenanofibrils，CNF）凝胶以其独特的生物亲和性、生物降解性和力学性能，可以广泛地应用到生物医药、食品等领域。然而，CNF在水溶液中易聚集而发生相分离，为了调控其聚集性能，有必要对其进行化学改性。今以商业化微晶纤维素为原料，采取无溶剂体系对其进行化学修饰，结合高压均质作用制备乙酰化纳米纤维素纤维（acetylated cellulose nanofibrils，ACNF）。利用流变仪、小角X射线散射仪、激光共聚焦显微镜等测试方法考察盐离子、温度对ACNF凝胶微观结构和宏观力学性能的影响。结果表明，ACNF呈现弯曲和无晶形的结构特征；其凝胶强度随着温度的升高先缓慢下降，而后急剧增加；而盐的加入能增强其凝胶强度，降低温度敏感性。无盐条件下，ACNF凝胶化主要基于纤维间热运动引起的物理缠结；而盐能促进体系发生浓度涨落，纤维因局部团聚经相互连接形成凝胶。

关键词(KeyWords)： 乙酰化;纳米纤维素纤维;流变;缠结;凝胶特性

Abstract:

Keywords:

基金项目(Foundation): 国家自然科学基金（21576116）。

作者(Author): 李英豪,耿延训,徐化能

DOI: 10.3969/j.issn.1003-9015.2018.01.028

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