Curing processes fractal analysis

The Fractal Analysis of Curing Processes of Epoxy Resins... 

The Fractal Analysis of Curing Processes of Epoxy Resins From relationship (10.1) it is possible to obtain ... 

Kozlov, G. V Bejev, A. A. Lipatov, Yu. S. The fractal analysis of curing processes of epoxy polymers. In book Perspectives on Chem. and Biochemical Physics. Ed. Zaikov, G. New York, Nova Science Publishers, Inc., 2002,231-253. 

Polymer mechanical properties are one from the most important ones, since even for polymers of different special-purpose function a definite level of these properties always requires [20]. Besides, in Ref [48] it has been shown, that in epoxy polymers curing process formation of chemical network with its nodes different density results to final polymer molecular characteristics change, namely, characteristic ratio C, which is a polymer chain statistical flexibility indicator [23]. If such effect actually exists, then it should be reflected in the value of cross-linked epoxy polymers deformation-strength characteristics. Therefore, the authors of Ref [49] offered limiting properties (properties at fracture) prediction techniques, based on a methods of fractal analysis and cluster model of polymers amorphous state structure in reference to series of sulfur-containing epoxy polymers [50]. 

Application of fractal analysis and irreversible aggregation models for the description of crosslinked polymer curing processes allows it to be elucidated that macromolecular coil (microgel) structure, characterised by its fractal dimension, plays a larger role than purely chemical aspects. Such an approach allows a quantitative description of both curing process kinetics and its final results to be received. 

Mechanical properties of polymers are among the most important, since a certain level of these properties is always required even for polymers of different special-purpose functions [50]. In papers [38, 51] it has been shown that the curing process of the chemical network of epoxy polymers with the formation of nodes of various density results in a change in the molecular characteristics, particularly the characteristic ratio C. If such an effect actually exists, then it should be reflected in the deformation-strength characteristics of crosslinked epoxy polymers. Therefore the authors [49] offered methods of prediction of the limiting properties (properties at fracture), based on the notions of fractal analysis and the cluster model of the amorphous state structure of polymers, with reference to a series of sulfur-containing epoxy polymers [52, 53] (see also Section 5.4). 

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