Optimisation of the production of foamed rubber goods with a lab scale method

The development of foamed rubber articles is a very complex process which i nvolves a large number of experiments. The target of these developments is usually the optimisation of the cell structure and surface appearance. Thes e are the most important properties that determine the performance of the f inished rubber article under service conditions. The experiments described here show that it is important to investigate the decomposition reaction of the blowing agent and the crosslinking reaction. It will be shown that these reactions interfere strongly with each other. T his leads to the conclusion that it is necessary to choose the blowing agen ts and the crosslinking agents very carefully. This paper describes experim ents with a formulation based on ethylene propylene diene rubber (EPDM) to investigate the different interactions caused by the ingredients in this fo rmulation. These experiments were performed on a lab scale. In addition, ex periments based on chloroprene rubber (CR) are described. These experiments prove the same interdependences of crosslinking and decomposition reaction . Furthermore, experiments will be described which show how the results can b e transferred from the lab scale to a factory scale trial.