Theory of relaxation properties of two-dimensional polymer networks, 2 - Local dynamic characteristics

Using normal mode transformation obtained in Part 1 of this series(1)), the exact analytical expressions for the mean-square displacements of junction s and nonjunction beads, the autocorrelation functions of the end-to-end ch ain vectors between neighboring junctions, and those of subchain vectors of a two-dimensional regular network consisting of "bead and spring" Rouse ch ains are obtained . Contributions of intra- and interchain relaxation proce sses to the local dynamic characteristics considered of compared. The time behavior of dynamic quantities obtained is estimated for different scales o f motions. The possibility of describing long-time relaxation of a two- dim ensional network by a simplified coarse-grained network model is demonstrat ed. It is shown that the focal relaxation properties of a two-dimensional p olymer network (as well as a three-dimensional network) on scales, smaller than the average distance between cross-links are very close to those of a single Rouse chain. The large-scale collective relaxation of the polymer ne tworks having a two-dimensional connectivity differs considerably from that of the three-dimensional networks.