羟乙基纤维素溶液的触变性与反触变性.pdf

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材料导报B:研究篇
2013年10月(下)第27卷第10期
羟乙基纤维素溶液的触变性与反触变性
丁松燕,刘红柱,柏莲桂,杨文,郏文涛
(合肥工业大学化工学院,合肥230009)
摘要对于高分子流体流动特性的研究不仅能够判断该流体的应用价值,而且还可以用于分析流体内部的结
构特点和结枸演变过程,建立流体的结构与性能关系。以羟乙基纤维素( FIEC)为研究对象,研究了HEC在水-乙醇
和水-乙二醇溶液体系中的流効性质。结果表明,HFC/水-乙醇溶液会发生从触变性到反触变性的转变,溶液稳态黏
度随着乙醇体积分数的增加先升后降;HEC/水-乙二醇溶液的流动特性更加复杂,虽然也会发生从触变性到反触变
性的转变,但是,相对低浓度的HEC溶液的稳态黏度随乙二醇体积分数的増加线性增长,而相对高浓度的HEC溶液
的稳态黏度却在乙二醇体积分数为15%和40%处出现两个极大值。结果表明:在体系中引入乙醇和乙二醇后,由于
非溶剂效应以及两种醇分子与HEC分子间的氢键作用,使得HEC在溶液中产生了不同的聚集状态,该聚集状态在
持续剪切的作用下又不断发生改变,从而影响了溶液的流动性质。
关键词羟乙基纤维素溶液流动特性分散与聚集
中图分类号:O631
文献标识码:A
Thixotropy and Anti-thixotropy of Hydroxyethyl Cellulose Aqueous Solutions
DING Songyan, IIU Hongzhu, BAI Liangui, YANG Wen, HAO Wentao
( School of Chemical Engineering, Hefei University of Technology, Hefei 230009)
Abstract Study on the flowing property of polymer fluids is not only suitable in evaluating their application
but also valuable in exploring the texture of the flowing system and its evolution, that is, the relationship between the
structure and the properties of the fluids. The hydroxyethyl cellulose(HEC) was chosen as the model compound, The
flowing property of the HEC in different aqueous solutions was studied The results showed that there was similar
transition from thixotropy to anti-thixotropy for both HEC/Water-ethanol solutions and HEC/ water-glycol solutions
There was only one maximum value of equilibrium viscosity for the HEC/Water-ethanol solutions in lower concentra
tion or higher concentration. It increased first, but decreased later with the increasing of volume fraction of the etha
nol. However, the flowing property of the HEC/Water-glyeol solutions showed to be more complex. There was no
maximum value of equilibrium viscosity for the HEC/Water-glycol solutions of lower concentration(0. 1wt%). It
creased linearly with the increasing of volume fraction of the glycol; whereas, there were two maximum value corre
sponding to glycol volume fraction of 15% and 40% for the HE/Water-glycol solutions of higher HEC concentration
(1.0wt %) It was speculated that there were different aggregation states of HEC in water-ethanol or in water-glycol
solutions, which were resulted from the non-solvent effect and the different interactions between the ethanol/glyco
with the HEC molecules. The aggregations of HEC molecules in solutions experienced destruction and recombination
under the constant shearing, which lead to the violent variation of the flowing properties
Key words hydroxyethyl cellulose, solution, flowing property, dispersion and aggregation
0引言
液、悬浮液等)中的分散状态往往会对体系的流动特性产生
重要影响,并最终决定了流体的应用价值。 Picard等对包括
羟乙基纤维素(HEC)是纤维素经环氧乙烷改性得到的HEC在内的一系列高分子材料的水包油乳液的剪切流动、
非离子型水溶性聚合物,分子结构如图1所示,具有良好蠕变回复等流动特性进行了研究。他们指出这有助于了解
的乳化、增稠、悬浮等特性,在化妆品、医药、悬浮聚合、建材特定材料在乳液配方中的作用。不仅如此,他们还深入研
等领域有着广泛的应用2-7。HEC在各种流体(如溶液、乳究了乳液流动特性与体系结构( Texture)之间的关系。
关安徽省自然科学基金(11040606M58);安微省教育斤自然科学重点项目(KJ2011A237);国家级大学生创新计划项目
丁松燕:女,1989年生,硕士生,研究方向为功能性高分子材料的制备及应用E-mail:812982483@q.com杨文:女,1973年生,
副教授,研究方向为功能性高分子材料的制备及应用E-mail:hfut@163.com