Modeling of crystal dissolution of poly(vinyl alcohol) gels produced by freezing/thawing processes

被引：129

作者：

Hassan, CM ^{[1
]}

Ward, JH ^{[1
]}

Peppas, NA ^{[1
]}

机构：

[1] Purdue Univ, Sch Chem Engn, Polymer Sci & Engn Labs, W Lafayette, IN 47907 USA

来源：

POLYMER | 2000年 / 41卷 / 18期

基金：

美国国家卫生研究院; 美国国家科学基金会;

关键词：

polymer dissolution; poly(vinyl alcohol); disentanglement;

D O I：

10.1016/S0032-3861(00)00031-8

中图分类号：

O63 [高分子化学（高聚物）];

学科分类号：

070305 ; 080501 ; 081704 ;

摘要：

A model was developed to describe the overall dissolution kinetics of semicrystalline PVA gels prepared by freezing and thawing techniques. The dissolution process was described as a three-step mechanism: detachment-, diffusion-, and disentanglement-controlled dissolution. The unfolding of crystalline regions due to detachment and diffusion was calculated. The lamellar thickness of a PVA crystal was found to significantly change the rate of unfolding and thus, the overall dissolution kinetics. The model predicted the effect of the lamellar thickness, time of swelling, and sample thickness on the crystal chain unfolding and potential dissolution of freeze/thawed PVA hydrogels. (C) 2000 Elsevier Science Ltd. All rights reserved.

引用

页码：6729 / 6739

页数：11