All India Rubber Industries Association (AIRIA) held another successful and insightful technical webinar on 28th May 2025, on Physical Testing of Rubber and Rubber like Materials, presented by Dr. Soumyadip Choudhury, in their latest Knowledge Series: Rubber & Beyond.
Dr. Soumyadip Choudhury earned his PhD from Leibniz Institute for Polymer Research Dresden (IPF Dresden) affiliated under TU Dresden, Germany in 2014. Thereafter, he stayed as post-doctoral fellow at the same institute for another year. During the period from 2015 to 2017, he worked as post-doctoral fellow at INM - Leibniz Institute for New Material in Saarbrucken, Germany.
He has been teaching Physical testing of Rubbers, Rubber Product Manufacturing Technology at PG level and Rubber Process Engineering, Science and Technology of Rubber & Rubber like Materials at UG level. His research domains are focused on rubber composites, hybrid nanofiller, nanostructured carbon, vulcanization, rubbers and polymers for energy storage, water remediation and so on.
The webinar started with Mr. Vishal Bagaria, Chairman, AIRIA, Eastern Region, introducing the speaker and welcoming the participants.
The webinar gave an overview of the characteristics of rubber compounds using rubber process analyzer curves and stress-strain graphs, comparing different materials and highlighting the unique properties of rubber.
Dr. Soumyadip Choudhury provided an overview of rubber technology and testing methods and explained that rubbers are amorphous polymers with low crystallinity and glass transition temperatures below room temperature, giving them elastic properties.
The session covered various types of rubbers, cross-linking methods and the importance of physical testing for quality control and product development. He also discussed different testing methods for unvulcanized and vulcanized rubbers, including plasticity measurements, viscosity tests and green strength evaluations and also explained the significance of tack in rubber compounds and various testing standards used in the industry.
Rubber Plasticity Testing Methods
He discussed the disk type test and plate type test for measuring rubber plasticity and explained that in the disk type test, a fixed size sample is compressed and heated, with the resulting thickness measured to calculate the Rapid Plasticity number. For the plate type test, a 2 cc sample is preheated, compressed, and the thickness change is used to calculate the plasticity number. He also mentioned recovery tests and aging tests to measure plasticity retention.
Rubber Compound Analysis and Properties
The characteristics of rubber compounds using rubber process analyzer (RPA) curves and stress strain graphs. He compared the behavior of carbon black-filled and silica filled natural rubber systems, highlighting differences in filler polymer and filler filler interactions. He concludes by describing the typical stress strain curve of rubber, noting features such as strain crystallization and hysteresis in filled elastomers.
The webinar was attended by 269+ participants. The session concluded with an engaging Q&A segment, where participants raised practical queries related to compound development and testing interpretation. He also expressed interest in developing a user-friendly book on rubber testing for industry professionals.
This knowledge sharing initiative reflects AIRIA’s ongoing commitment to advancing technical expertise in the rubber industry. The next webinar is scheduled for the first week of June 2025.