### Calculation of average sizes of oligomersin case of equilibrium polycondensation

Pages 146-154

Experimental and theoretical research into polymeric solutions and melts obtained in the condition of equilibrium condensation requires a theoretical size-distribution function to be identified. The author presents his solution to this problem using generating functions, although no Gaussian statistics of polymer chains is employed.Method of branching processes proposed by Gordon is a common way to consider configurational statistics of branched polymers that allows researchers to obtain generating functions in a simple way. Unfortunately, this method cannot be directly applied to non-ideal chains, while effects of hindrances of rotating round bonds between two monomers may be of significant importance in terms of experimental data interpretation. The author presents a new method based on the mathematical theory of formal context-free grammar applicable to non-commutative objects, like matrices. The proposed method combined with the Flory’s approach was applied to tree-like polymers with hindered rotation and analytical expressions to derive generating functions.

DOI: 10.22227/1997-0935.2013.3.146-154

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