The role of end groups in analysis of the properties of polymers

Abstract

The effect of the chemical structure of end groups of some polymers on their physical characteristic is analysed. It is shown that, depending on the type of initiator used in polymer synthesis, this effect can be very considerable, especially at small degrees of polymerization. The effect is analysed for the polymers polymethyl metnacrylate, polystyrene, polyethylene terephthalate, and polycarbonate, on the basis of bisphenol A. The role of the Van der Waals volume and the polarity of the end groups in evaluating the molecular refraction, conhesion energy, solubility parameters, and the surface tension is brought out. The values of the degrees of polymerization for which the end group effect is negligible are determined. © 1990.