Can you tell us a little about your background?
I joined Apollo Tyres in 1998 with the responsibility of setting up a new R&D center for the organization. My role and responsibility changed over time, from head of R&D to head of global R&D and raw materials, head of global raw materials, compound development and external research, and, as of June 2015, head of special project materials.
What are the key challenges in your field currently?
The world’s population is growing. Urban and middle class populations are growing even faster. And people’s aspirations and the number of vehicles on the road are increasing day by day. This is depleting the earth’s resources fast and creating uncertainty about sustainability, which depends upon the reduction of waste, and reuse and recycling. In order to achieve this, global tire companies are working toward two goals.
In the short term, this means meeting tire labeling criteria, especially reducing rolling resistance and the carbon foot print by enhancing fuel efficiency. In the long term, the most prominent goal is to reduce material usage and that is why we are researching the use of nanomaterials as we believe they are key to the future sustainability of products because they provide more for less.
How do nanomaterials provide more for less?
Nano-scale materials are defined as a set of substances with at least one dimension that is less than approximately 100 nanometers. Nanomaterials are of interest because at this scale unique mechanical, optical, magnetic, electrical and other properties emerge.
At this dimension, material-dependent interface effects and large specific surfaces become more important. At this order of magnitude, quantum effects appear that exhibit a unique potential for novel functionalities. The critical size below which material properties change depends on the material itself. By changing the size of such components, it is possible to produce composites with radically new properties and functionalities.
Nano-composites are materials that incorporate nano-sized particles into a matrix of standard material such as polymers. This addition of nano-particles can generate a drastic improvement in properties including mechanical strength, toughness and electrical or thermal conductivity, as well as processing behavior. The effectiveness of the nano-particles is such that the amount of material required to be added is normally 0.5-5.0% by weight. They also have properties that are superior to conventional micro-scale composites. Thus these materials offer ways to create smaller, cheaper and lighter devices that can do more, using less energy and materials.
Please tell us about the research you have conducted into the use of nanomaterials.
We have conducted a study based on: the composites of SSBR-BR with a hybrid filler system of highly dispersible silica and nanosilica; and enhancement of their interaction through T- and E-beam irradiation of the fillers.
Experiments have revealed that these irradiated HD silica and nanosilica-based composites show remarkable enhancement of polymer-filler interaction and thus result in an extension of the magic triangle properties, enhancing physicomechanical and dynamic performance of the tire tread compound. We have managed to enhance the polymer-filler interaction by electron beam and gama radiation of the nanosilica.
Have you tested this new technology in prototype tires?
We have conducted several projects in our laboratory and published our findings in different international journals although so far we have not applied our observations to tires. We do, of course, plan to validate our findings in tires in the near future.
What are the potential implications of this work?
Before commercialization, we need to fine-tune our innovation. There is huge scope for the optimization of these formulations in developing high-performance composites, including tires, by optimizing HD silica and nanosilica loading with respect to the silane coupling agent. Silane-sulfur and accelerator dose optimization is suggested for adequate crosslinking, since most of the composites made using partially replaced silica, as well as modified silica and nanosilica, have shown relatively low crosslinking density.
The effect of gamma and electron beam irradiation on HD silica and nanosilica may be studied in detail to understand the changes in silanol groups and the optimization of silane and other curatives. Further study is necessary to understand the interaction between the rubber matrix and the fillers. Optimization of the radiation dosage is essential as per end-product requirements. The technology could be easily scaled-up using simple and inexpensive techniques.
December 8, 2015
