Molecular kinetics during the growth of the macromolecule poly(di-2-hydroxypropyl ether of bisphenol-A–n-hexylamine) studied by dielectric spectroscopy

Abstract

The growth of a polymer by step-polymerization reactions between n-hexylamine and the diglycidyl ether of bisphenol-A has been studied by measuring the dielectric properties over a wide range of frequency. Additionally, the dielectric properties of the monomeric and polymerized states have been studied and the effect of non-stoichiometry on localized motions in their glassy states investigated. This has led to an examination of the dielectric behaviour of the time-invariant states and time-variant states of a chemically reacting substance ultimately producing a macromolecule. Both states could be described by analogous equations in which the relaxation had a broad distribution of times expressed as the non-exponential decay of polarization. For the α-relaxation process in the polymerized states, this distribution was narrower than for the molecular state. Part of this effect was due to the temperature. In the polymerized state, the shape of the spectrum remained constant with changing temperature but it narrowed with increasing temperature for the molecular state. The study showed how the relaxation time evolved with the reaction time and that the relaxations observed in the glassy state are appropriately interpreted in terms of difference in the local packing density of the structure.