Please tell us about the study upon which your presentation at Tire Technology Expo 2016 was based.
As a foresight researcher at Barez Industrial Group, Tehran, Iran, I conduct development projects to improve products in the raw materials field. This particular study was a cooperative study in partnership with the Science and Research Branch Islamic Azad University (SRBIAU) University.
It is widely known that the rheological behavior of rubbers is of great importance regarding their affect on rubber processing. In this study, entitled Rheological behavior of butyl rubber and the effect of process oil on its rheology, we analyzed the effect of different amounts of oil on the processing behavior of rubber in a wide range of shear rates similar to shear rate ranges of real rubber processes
What were your findings?
First of all, we found that butyl rubber obeys the power law. The power law predicts that the effective viscosity would decrease with increasing shear rate indefinitely, requiring a fluid with infinite viscosity at rest and zero viscosity as the shear rate approaches infinity.
We found that enhancing the amount of process oil in the rubber matrix increases the slip velocity particularly in dies of large lengths, which would not be a desired result in certain cases. We also found that processing behavior might be affected by process temperature. In this case, we found that the effect of temperature on slip velocity seems to be related to shear rates as well; for instance, at lower shear rates, when temperature increases, slip velocity decreases, while a reverse result would be obtained at higher temperatures.
What is the next step in this research?
Next we aim to study oil-rubber compatibility and the effect of the aforementioned parameter on rubber processing behavior and other rubber properties.
May 12, 2016