New insights into the mastication process

The viscosity of NR is reduced either by mastication or by peptisation, thereby breaking down the long polymer chains and sacrificing part of the good dynamic properties to processability. Standard chemical peptizers were designed for the use in separate mastication steps which are unusual in the industry nowadays. Early filler addition has a big impact on the peptizer performance. in this study we have compared the different strategies, additives and mixing sequences commonly used by the industry to identify the best method of viscosity reduction. The evaluation included viscosity of different compounding steps, time, energy consumption, costs and dynamic properties of final product and yielded some interesting and surprising results.