MOLECULAR-MODEL FOR THE MECHANICAL-PROPERTIES OF ELASTOMERS .3. NETWORKS CROSS-LINKED IN A STATE OF STRAIN

A molecular model developed previously has been extended to a study of the elastic properties of elastomers cross-linked in a state of strain. The model allows a detailed analysis of both the network connectivity upon cross-linking and the mechanical properties upon tensile deformation. The nonaffine displacements of the network junctions during deformation is also fully taken into account. The results show that the permanent set and modulus values in the state of ease increase with an increase in the strain at which the cross-links are introduced. However, in contrast to the predictions of previous theories, these moduli and permanent set values level off at high cross-linking strains. © 1990, American Chemical Society. All rights reserved.