MODULUS OF POLYBUTADIENE NETWORKS MADE BY HYDROSILATION CROSSLINKING.

Our results from small strain data can be best explained using a network model that includes the effect of topological interactions. The use of two polybutadienes of similar structure, but different plateau modulus, shows the change in the topological interaction effect. The differences in the parameter h for both systems show the different importance of the effect of entanglements on the suppression of junction fluctuations. Since the crosslinking junction of both systems are of the same type and functionality, the suppression of mobility is larger in the networks formed from polymers of larger plateau. For these systems, this is, in turn, related to the polymer backbone, since for polybutadienes the lower the vinyl content, the larger the plateau modulus. The NMR studies and the maximum modulus at r equals 1 indicate that for the aromatic silane used here, side reactions, which are common for hydrosilations using siloxysilanes, do not occur. Thus aromatic silanes are recommended for further model network studies.