Population Balance Methods for Modeling of Sulfur Vulcanization of Natural Rubber Compounds

The population balance methods are employed to model sulfur vulcanization process of natural rubber (NR) compounds. The proposed primary models are so far empirical and/ or mechanistic and have various limitations that do not embody all reactions and formation of all the process products. In this work، the models are developed، using population balance methods that explicitly acknowledge the nature of all the formed species and the various types of reactions. The kinetic model can also accurately describe the complete cure responses including the scorch delay، cure time and the reversion for a wide range of compositions، using a single set of rate constants. In addition، the concentration profiles of all the reaction intermediates as a function of polysulfidic lengths are predicted. The population balance model provides a quantitative framework for explicitly incorporating mechanistically reasonable chemistry of the vulcanization process of different natural rubber compounds.