Improved Air Retention For Environmental Tyres
Developing ‘green car tyres‘ involves considering many different variables, most of which involve the tyres’ life of road use as that impacts most on the environment. Maintaining tyre pressure has a major positive effect on prolonging a tyre’s life.
The three main considerations when designing environmentally friendly tyres are:
- rolling resistance is mostly dependent on turning momentum, so reducing it can be accomplished by maintaining the tyres’ pressure and shape.
- the weight of the tyres effect the moment of inertia of the tyres and fuel efficiency.
- incorrect tyre pressure can increase wear on both the crown and sidewall flexing.
From this it is easy to see that tyre pressure has a lot to answer for! The biggest issue with maintaining tyre pressures isn’t in fact that drivers don’t check often enough (although they usually don’t!), it is that air is constantly seeping out of the tyres, lowering the tyre pressure. Most tyres have an inner liner made from butyl rubber which has an air permeability less than 10 per cent that of natural rubber.
Tyre manufacturers have been working on developing a third generation of inner liner technology. One company have come up with SEIR (Super Efficient Inner Liner) which uses nylon to reduce the air permeability and is three times as airtight as butyl rubber. The next step is commercialising the product and then we will hopefully see tyres made with it being fitted to our cars.