Derivation of the chain length distribution in crosslinked elastomers from thermoporometric literature data

Abstract

Thermoporometry appears to be an under-exploited technique to obtain an insight of polymer network properties, and chain length distribution in particular. In this paper, the derivation of a relationship between raw differential scanning calorimetry (DSC) data of a solvent-swollen natural rubber (i.e. basic data for thermoporometry applied to polymers) and chain length distribution is conducted, based on the literature relating first DSC data to pore size distribution. Thanks to these results, a description of the crosslinking process is proposed, highlighting successive stages of network organization. Results are in agreement with experimental mean chain length, and responses observed in mechanical and swelling experiments. The thermoporometry data analysis and the breakdown of crosslinking process into different stages are expected to introduce a rational description of network transformation at different crosslinking degrees.