Abstract
A gel is taken to be a polymer–solvent system in which the polymer, present at very low concentration, forms a quite stable three-dimensional network in the solvent. Consideration is given to the properties of gels in which the network is formed both by chemical and by physical bonds; attention is paid mainly to the second group of gels, in which variation in temperature produces a reversible transition between gel and solution. Existing views on the thermodynamic nature and structure of gels are subjected to critical analysis, and specific gel-forming systems are examined. A detailed analysis is made of the macroscopic phenomena accompanying the reversible solution–gel transition, as well as the strength, rubber-elastic, plastic, and relaxation properties of gels.
A list of 399 references is included.