ABSTRACT
Traditional methods of determining information about the nature of the rubber matrix for unfilled rubbers, namely the average crosslink density, are based on analysis of mechanical properties. For example the tensile properties of rubbers can be directly related to their crosslink density through the Mooney-Rivlin treatment as can the degree to which rubbers will swell in a suitable solvent (Treloar 1975). The FloryRehner relation (Equation 1) relates the volume fraction of rubber in a swollen network to the crosslink density (Equation 2). Where vr is the volume fraction of rubber in the swollen network, χ is the Flory-Huggins interaction parameter, ρ is the density of the rubber hydrocarbon, V0 is the molar volume of the solvent, Mc is the chain molecular weight between crosslinks and [X] is the crosslink density in units of moles per cubic metre.
