Chiral side chain copolymers, 4 - Kinetics of the phase transition from liquid melt to an amorphous phase with a hidden layer structure - the "isotropic smectic" state

The kinetically controlled mesophase formation has been observed for a seri es of photochromic side chain copolymethacrylates. Up to 25% of azobenzene dichroic moieties, the copolymers form an optically isotropic mesophase wit h layer ordering - the "isotropic smectic" phase, IsoSm*. The kinetics of t he Iso-IsoSm* phase transition, as studied by DSC and X-ray techniques, in some cases cannot be explained in terms of a single :Avrami equation. A two -step mechanism is suggested including the transformation from the monolaye r to the bilayer structure. The dependence of the transition temperature on annealing temperature has been estimated.