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The reversible copolymerization is described by a model derived from simple kinetic assumptions. The copolymerization behaviour of a system can be calculated from 3 experimental parameters: composition of the monomer mixture, composition and diade distribution of the copolymer. Four additional model constants represent the connection with the thermodynamics of reversible copolymerization. The model leads to the same results as the Monte-Carlo method described in the literature. The temperature dependence of reversible copolymerizations can be simulated by the model with the thermodynamic values of the four elementary reactions.

The relaxation of holographic phase gratings was examined to obtain some information about the involved photochemically induced changes. The studies were performed with statistical liquidcrystalline side group copolymers having different concentrations of the azobenzene dye. The formation of mesophases, which normally exist in the thermodynamic equilibrium, was prevented during the sample preparation by quenching the polymer films. Two relaxation processes were found in this glassy state of the polymers. The faster one could be described by a dispersive stretched exponential function and was attributed to relaxation processes which are related to the amorphous phase of the sample, while the slower one, corresponding to a single exponential process, correlates with the formation of light-induced liquid-crystalline microstructures. The latter are believed to be the main cause for the modulation of the refractive index.

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