DYNAMICS OF STIFF POLYMERS WITH THE SLIGHTLY-BENDING-ROD MODEL

The dynamics of stiff polymers in the liquid or liquid-crystalline sta te is usually described by the rigid rod model. To account, at least t o a first approximation, for the partial flexibility of the actual cha in, the slightly-bending-rod model has been recently proposed, and a s implified two-dimensional version of the model has been developed in s ome detail. In this paper, we consider the full three-dimensional dyna mic equation which, in its general form, is too complex for predictive purposes. We then derive a reduced form of the dynamic equation on th e basis of the fact that some of the configurational variables have a much faster dynamics than others. The mathematical structure of the re duced form, though still complex, is close enough to that of the rigid rod model to allow for predictive calculations. (C) 1998 Elsevier Sci ence B.V. All rights reserved.