Interplay between Gelation and Phase Separation in Aqueous Solutions of Methylcellulose and Hydroxypropylmethylcellulose

Thermally induced gelation in aqueous solutions of methylcellulose (MC) and hydroxypropylmethylcellulose (HPMC) has been studied by rheological, optical microscopy, and turbidimetry measurements. The structural and mechanical properties of these hydrogels are dominated by the interplay between phase...

Full description

Saved in:
Bibliographic Details
Published in:Langmuir 2012-07, Vol.28 (28), p.10551-10557
Main Authors: Fairclough, J. Patrick A, Yu, Hao, Kelly, Oscar, Ryan, Anthony J, Sammler, Robert L, Radler, Michael
Format: Article
Language:English
Subjects:
Chemistry
Colloidal gels. Colloidal sols
Colloidal state and disperse state
Exact sciences and technology
Gels - chemical synthesis
Gels - chemistry
General and physical chemistry
Hypromellose Derivatives
Methylcellulose - analogs & derivatives
Methylcellulose - chemical synthesis
Methylcellulose - chemistry
Molecular Structure
Porous materials
Rheology
Solutions
Thermodynamics
Water - chemistry
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Thermally induced gelation in aqueous solutions of methylcellulose (MC) and hydroxypropylmethylcellulose (HPMC) has been studied by rheological, optical microscopy, and turbidimetry measurements. The structural and mechanical properties of these hydrogels are dominated by the interplay between phase separation and gelation. In MC solutions, phase separation takes place almost simultaneously with gelation. An increase in the storage modulus is coupled to the appearance of a bicontinuous structure upon heating. However, a thermal gap exists between phase separation and gelation in the case of HPMC solutions. The storage modulus shows a dramatic decrease during phase separation and then rises in the subsequent gelation. A macroporous structure forms in the gels via “viscoelastic phase separation” linked to “double phase separation”.
ISSN:0743-7463
1520-5827
DOI:10.1021/la300971r