β Scribed by V. V. Shilov; N. E. Kruglyak; Yu. S. Lipatov
No coin nor oath required. For personal study only.
The method of the modeling of the radial distribution function for liquid and amorphous polymers is described. The method consists in the use of pair functions of the radial distribution (ideal peaks) for the construction of the distribution function of intramolecular distances and the comparison of the theoretical function with the experimental one. The theoretical functions for two possible conformations of the poly(tetramethylene glycol) macromolecule were computed. It follows from comparison of the computed theoretical functions with the experimental one that the intramolecular distances do not become apparent in the experimental curve. The differential functions containing the contributions of the intermolecular distances only were obtained by subtraction of the theoretical function from the experimental. Comparison of the differential functions of the two conformational states which were taken as models proved that there are large numbers of gauche conformations in the liquid polymer in contrast to the crystalline polymer. On the basis of the analysis of the differential functions for liquid and crystalline poly(tetramethylene glycol), we concluded that the shortβrange order of the polymer is distorted during the melting in that the basic plane of the poly(tetramethylene glycol) paracrystal becomes almost hexagonal.
π SIMILAR VOLUMES
After discussion of the various modelling concepts. a broad classification of short range order (sro) is suggested. differentiating between uniform and bounded 'micro-domains' and unbounded 'static concentration wave packets'. It is explained why this classification is physically useful, and how tra