A comparison of three polymer network models in current use

摘要

The relationship between three theories of polymer network deformation is explored. The theories are: the eight-chain model of Arruda and Boyce; the full network model of Wu and van der Giessen; and the crosslink-sliplink model of Edwards and Vilgis. All have a history of use as the network component in theories of solid polymer deformation. Given results from either the eight-chain or full network models, least-squares fitting of the stresses is used to derive optimal parameters of the Edwards-Vilgis model. Both the eight-china and the full network models can be closely approximated by an Edwards-Vilgis model, provided the finite chain extensibility limit is not approached too closely. The eight-chain model is found to be equivalent to an Edwards-Vilgis model with a small number of sliplinks, whereas the full network model corresponds to an Edwards-Vilgis model with no sliplinks. The physical interpretation of these findings is discussed.