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Title
Abstract
Present Strategies and Future Outlook
Reversible Gek and Related Systems
Direct Methods
Indirect Methods
References
All Topics
Engineering
Materials Science

A Perspective on Reversible Gels and Related Systems

Profile image of Paul RussoPaul Russo

1987, American Chemical Society eBooks

https://doi.org/10.1021/BK-1987-0350.CH001
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21 pages

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Abstract

The features common to reversible polymer gels of many types are identified and discussed. The nature of the gel state is carefully defined, and a novel classification scheme based on morphology, rather than chemical or mechanistic considerations, is proposed. The article also serves as an overview to some of the more commonly used techniques used in the study of gels, and as an introduction to some of the current trends in reversible gel research. Some speculations regarding future trends in reversible gel research are presented. Of all the physical states, there is something especially elusive about gels. Systems which gel reversibly are particularly difficult to understand, for the requirement is that an enormous transformation of physical state must occur, usually involving only a small portion of the system. Yet an astounding variety of mechanisms can result in reversible gelation, and it seems that a general understanding of reversible gels will not soon be achieved. Perhaps the greatest universality is presently found in the objectives of gel researchers and the obstacles to meeting them (1). The would-be gel researcher must first confirm positively that the system is a gel. Even this isn't always trivial. Next, the conditions under which reversible gelation occurs must be carefully mapped out. Recent controversies show that this matter is often complex, too. After these preliminaries, a structural analysis of the gel is appropriate. Next, it is often of considerable interest to undertake the kinetic study of how the structure forms during gelation-a question which is often the most difficult of all. Finally, we may add such practical concerns as the commercial utility or biological function of the gel.

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