Structure formation coagulation processes

Structure formation that takes place in disperse systems is the result of spontaneous thermodynamically favorable processes of particle aggregation that lead to a decrease in free energy of the system. These processes include coagulation of dispersed phase or condensation of substance in the zones of direct particle contact. The development of spacial networks (disperse structures) of different kinds defines the ability of disperse system to be converted into a material with particular mechanical properties. Such system becomes qualitatively different from its initial, unstructured state. 

This polycondensation reaction may also involve the participation of aluminum salts. In this reaction, first, a sol of silicic acid or aluminosilicic acid is formed. This sol then undergoes coagulation and forms a gel, which serves as the primary coagulation structure. In the presence of supersaturation, the gel particles undergo bridging with the formation of phase contacts, and the condensation structure develops. This process is the basis for the synthesis of numerous catalysts and adsorbents. 

Our objective is thus to characterize the structure of the polymer network formed during coagulation in the spinning process, as well as the structure obtained by slow coagulation, and to consider the formation of such structures in terms of the phase transformations in rigid polymer solutions. 

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