Conti gives overview of green developments
The commercial availability of Sumitomo’s Enasave 97, albeit in small volumes, has demonstrated the feasibility of producing tyres containing very little in the way of fossil fuels. Introducing completely or nearly fossil fuel-free products in greater quantities is a goal held by all tyre majors, and Continental’s head of material and process engineering has shared some details about the German tyre maker’s progress in this direction.
Dr. Boris Mergell reports that today’s standard tyres contain about 45 per cent non-oil based raw materials, and Continental’s chemists have helped the tyre maker increase this percentage by replacing fossil oils with rapeseed oils and polyester with rayon as reinforcement within the tyre’s casing. At the same time recycled tyre rubber increasingly serves as a substitute for synthetic and natural rubber in tyres. Continental suggests it may have a 100 per cent natural raw materials tyre ready by 2020, but this is easier said than done.
“Not all raw materials in tyres can simply be replaced by renewable materials,” explains Mergell. “In many cases, such materials have a negative impact on braking performance or rolling resistance – and we will not accept any compromise here. Also, the widespread replacement of fossil materials with renewable raw materials is not always a solution since it requires acreage that might already be used in food production.”
Nevertheless, Dr. Mergell sees the introduction of tyres made with sustainable materials as achievable within this coming decade. “We still need to conduct numerous tests on materials and in our process engineering to make significant progress,” he says, but adds that the introduction of ‘green tyres’ is coming in the next five years or so.
Technologies currently under investigation at Continental include rubber extraction from dandelion, which presents a promising potential replacement for rubber extraction from hevea trees. Dr. Mergell shares that since dandelion is grown on fallow fields in Europe, it would neither compete with food products nor require long distance transportation to European tyre plants. Further materials that can potentially be used in tyres include plasticisers and resins, either acquired from renewable resources or recycling facilities.