| | |  | | | | Record from Web of Science® | | | | | | |
| VOLUME TRANSITION IN A GEL DRIVEN BY HYDROGEN-BONDING |
|
|
| Author(s): ILMAIN F, TANAKA T, KOKUFUTA E |
| Source: NATURE Volume: 349 Issue: 6308 Pages: 400-401 Published: JAN 31 1991 |
| Times Cited: 225 References: 18 |
| Abstract: INTERACTIONS between macromolecules fall into four categories: ionic, hydrophobic, van der Waals and hydrogen bonding. Phase transitions in polymer gels provide a means of studying these interactions. Many gels will undergo reversible, discontinuous volume changes in response to changes in, for example, temperature, gel composition or light irradiation 1-5. These transitions result from the competition between repulsive intermolecular forces, usually electrostatic in nature, that act to expand the polymer network, and an attractive force that acts to shrink it. Volume transitions in gels have been observed that are driven by all of the above-mentioned forces except hydrogen bonding (ref 6-10; T.T. et al., unpublished data; H. Inomata et al., personal communication). Here we report on a phase transition in an interpenetrating polymer network of poly(acrylamide) and poly(acrylic acid) that completes this picture - it is controled by cooperative 'zipping' interactions between the molecules which result from hydrogen bonding. Cooperativity is an essential feature of the interactions, in the independent hydrogen bonds would not provide a sufficient driving force for the transition. A further novel characteristic of this phase transition is that the swelling (in water) is induced by an increase rather than a decrease in temperature. |
| Document Type: Article |
| Language: English |
| Reprint Address: ILMAIN, F (reprint author), MIT, DEPT PHYS, CAMBRIDGE, MA 02139 USA |
Addresses:
1. UNIV STRASBOURG 1, ULTRASONS & DYNAM FLUIDES COMPLEXES LABS, F-67070 STRASBOURG, FRANCE
2. UNIV TSUKUBA, INST APPL BIOCHEM, TSUKUBA, IBARAKI 305 JAPAN
3. MIT, CTR MAT SCI & ENGN, CAMBRIDGE, MA 02139 USA |
| Publisher: MACMILLAN MAGAZINES LTD, 4 LITTLE ESSEX STREET, LONDON, ENGLAND WC2R 3LF |
| Subject Category: Multidisciplinary Sciences |
| IDS Number: EV514 |
| ISSN: 0028-0836 |
|
| | | | | | | | | Record from Web of Science® | | | | | | | | | |