Reinventing the wheel

Keeping your car tyres inflated to the correct pressure isn’t just a matter of safety. It reduces stress and irregular wear. And, across an entire economy, it can also save millions of litres of petrol a day. That’s where Exxpro comes in, a recent ExxonMobil innovation that may revolutionize the tyre industry. A blend of synthetic rubber and nylon, Exxpro allows for lighter and more durable tyres that roll easier and maintain proper air pressure far longer than conventional tyres. These characteristics lead to vehicles that use less fuel and create fewer emissions.

A car with underinflated tyres burns up to an extra tank of petrol every year. Consumers can help reduce fuel usage by checking that they have the proper tyre pressure more frequently. However, no matter how often you check, a tyre that holds air better will have less underinflation on average, thereby using less fuel.

The new product features specialty elastomers (an elastomer is a rubber, typically used to impart elasticity to a product), which are isobutylene-based materials similar to butyl rubber. They are used in hundreds of products from soccer balls to conveyor belts. Butyl rubber and its cousin, halobutyl rubber, prevent air leakage much better than natural rubber or other traditional synthetic elastomers, which is why they have been used in inner tubes and tyres for over half a century. ExxonMobil researchers invented butyl rubber in the 1930s, and the company has long been a technology leader in the butyl industry. Today, ExxonMobil Chemical makes several types of butyl rubber, supplied to tyre manufacturers and other customers worldwide.


As thin and light as a plastic bag
Over the past years, ExxonMobil scientists developed a revolutionary new form of synthetic rubber, brand named Exxpro specialty elastomers. The material can be dynamically blended with nylon to form a unique alloy that combines the flexibility and elasticity of rubber with low air permeability.

"This new material is superior in many ways," says Howe-Yong Hong, butyl marketing manager at ExxonMobil Chemical in Houston. "Most passenger tyres today have a halobutyl innerliner that’s about 0.8 millimetres thick and weighs about 1 kilogram. Our new material is as thin and light as a plastic bag. This means nearly 80 percent less weight and a far better job of preventing air leakage."

ExxonMobil and Yokohama Tyre Company of Japan developed the new product, which is called Exxpro Nylon DVA. Over several years, the companies conducted research with alloys of the new elastomer materials and their use in tubeless tyres. Several tyre manufacturers are now testing the material and evaluating its application in their product lines.

Saving energy during production
Producing isobutylene-based synthetic rubber is a complex and energy-intensive process. Butyl rubber and Exxpro specialty elastomers are manufactured in frigid conditions approaching minus minus 101 degrees Celsius. Achieving such low temperatures consumes a lot of energy. This has recently changed, however.

"ExxonMobil’s research and technology organizations developed an amazing new process that allows us to manufacture butyl rubber and Exxpro specialty elastomers in a substantially warmer environment," saysJames Stokes, Technology Managerat ExxonMobil Chemical in Houston. "That’s a huge breakthrough and is possibly the most significant development in the butyl industry in 50 years. It will allow us to substantially increase our production capacity at the manufacturing sites with the technology enhancement. So, we’re increasing production while saving energy and lowering costs."

Exxpro specialty elastomers manufactured at Baytown, Texas will be shipped to Pensacola, Florida, where ExxonMobil Chemical is building a manufacturing plant that will blend the products with nylon. The resulting dynamically vulcanized alloy can be made into sheets of film for use in tyre innerliners. The Florida facility will be completed in 2008 and will supply customers worldwide. In addition, butyl capacities in France and Japan were expanded.

Tyre Pressure Tips
•        Check the tyre pressure of your car once a month
•        Tyre pressure must be checked at cold tyres – this means you must have driven less than three kilometres or wait for 10 minutes to let the tyres cool down
•        Car manufacturers always recommend two different tyre pressures: one for driving unloaded and/or mainly at normal speeds and one for driving fully loaded and/or mainly at high speeds. Check your instruction manual pressure recommendations
•        Newly sold passenger cars of several makes are already equipped with an electronic system that continually monitors tyre pressure. Such systems can also be fitted as an accessory in other cars

 
(Source:http://www.ecodrive.org/Additional-Tipps-and-Tricks.229.0.html)