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Wide-line 1 H NMR spectroscopy was used to investigate the kinetics of director rotation in the comb-shaped nematic polymer [CH 2 CH(COOR)] n (R= (CH 2 ) 4 OPhPhCN).The director rotation was found to conform to the following general features: the experimentally observed kinetics of director reorientation was interpreted in terms of the monodomain model; coefficients of rotational viscosity versus temperature plots were satisfactorily described by the Arrhenius equation with abnormally high activation energies; activation energy increased with an increase in polymer chain length; the rotational viscosity coefficient was related to polymer chain length via an exponential dependence; and an increase in temperature was accompanied by a linear increase of the exponent from 0.9 to 2.2

Kinetics of the model reaction between oligomeric planar lattice-model chains has been studied by Monte--Carlo method. Simulation of the chain's motion was performing using rules of Verdier--Stockmayer. The length of chains has been varied from 8 to 24 beads. The probabilities of breaking of a contact between two chains was given by w=exp(--U); the formation of an adjacent contact was controlled by mobility of chains. The probability of the formation of any isolated contact was given by w0=exp(--U0). Kinetic curves were obtained for mean number of contacts Z(t) with different initial conditions and U, U0 values. The estimation of mean rates of formation-breaking of contacts (V+ and V-) and their dependences on the time, U and U0 have been obtained. Rate constants for the formation-breaking of a contact (k+ and k-) were estimated as well as the distribution for k+/- over states of the binary complex. The calculations were made for the case of homopolymers, intrachain interactions were omitted.