Source: AvD / Fotograf Tom Linke ad08

Polymer materials are the future:

mobility depends on rubber

Modern cars consist to a large extent of plastic. More than 2,000 components are polymer-based. The situation was completely different when the automotive age began. The first cars were iron-based and very heavy – wood was only used here and there. One polymer material has been involved right from the start, however: rubber. It is a fair question: would the car industry have become what it is today if ingenious engineers and polymer experts – particularly John Boyd Dunlop (1841-1921) – had not made crucial progress in the development of pneumatic tyres? The Oldtimer Grand Prix, which is being held by the German Automobile Club (AvD) at the Nürburgring Race Track from 9. to 11. August 2013, is a good opportunity to look back at the historical moments in the automotive age.

Just for the sake of complete accuracy, it should be mentioned that the Scot Robert William Thomson invented the pneumatic tyre as early as 1845. This tyre consisted of one or more canvas tubes that were impregnated with rubber and covered with leather. He was way ahead of his time with his invention, however; not even bicycles that needed pneumatic tyres existed back then. Some vehicles did at least run on Thomson tyres too later on: some of them had several different chambers (tubes) for the air and were to a certain extent the predecessors of a number of designs for puncture-resistant tyres.

Pneumatic tyres were put to a long-distance test seven years after John Boyd Dunlop obtained a patent for air-filled tyres – in 1895. The brothers André and Edouard Michelin chose these tyres for the Paris-Bordeaux-Paris car race, in which they participated with a Peugeot car known as “Eclair” (lightning). They did not prove to be much of a help, however, because they did not finish the race in first place; on the contrary, they only just managed to finish at all: they suffered 50 breakdowns and had to change the tyres 22 times in what were sometimes laborious operations. The winner – Emil Layassor – did not face the same problems: he opted for solid rubber tyres.

Although this was a major defeat for the Michelin brothers personally, it did not have any adverse effect on tyre development. In fact, things really started to get going after this. The first cars with pneumatic tyres were already being supplied directly from the factory only three years later. Continental included car tyres in its range for the first time in 1899 too. Price: 269 marks, useful life: 500 kilometres. In the same year, the Belgian Camille Jenatzy reached a speed of more than 100 km/h – an incredible feat at the time – with an electric vehicle and special pneumatic tyres supplied by Michelin. Ultrafast driving normally started at only 20 km/h at this time, because the maximum possible speed was generally around 15 km/h.

 
 
Quelle: istockphoto

Appearances are important

Tyre design changed around 1904: they were given more distinctive tread, while they became less colourful at the same time. Tread with cross ribbing was where the future lay. The addition of carbon black – which is standard procedure to this day – increased the strength of the rubber, which in the final analysis led to a longer useful life. Whereas they tended to be yellowy-white before, tyres were now black.

There were other important stages in the development of tyres to what they are today, however: they quite literally took to the air in 1915, when Pirelli manufactured the first pneumatic tyres for aircraft. Two years later, Goodyear produced the first pneumatic lorry tyres and Bayer introduced synthetic rubber for the first time, which was a major step forward for the tyre industry. Another decisive change was made to pneumatic tyres in 1922: at the International Motor Show (IAA), Dunlop presented the first car tyre with steel wire in the bead, so that it fitted better on the rim – something that has been standard in production since 1924.

We now jump to 1943: patents are filed in quick succession. Continental obtains one for tubeless tyres – a standard feature nowadays – while Michelin is granted one three years later for steel-belted tyres. In 1950, two letters caused a sensation in the tyre community: M+S. Although the first mud + snow tyres had deep tread and were loud, they performed better than other tyres in wintry road conditions. It was not until 30 years later that Goodyear presented the first genuinely all-season tyre. This tyre was a very sensible solution for people who did not buy winter tyres, as it was suitable for all weather conditions. Like its successors, it was identified by M+S lettering on the side of the tyre.

 
 
Source: istockphoto

Car tyres made from dandelions and soy

An in-depth description of what happened after this can be found in one of our Topics of the Month “Tyres, tyres, tyres – how it all began”. For the sake of complete accuracy – once again – another facet needs to be added at this point. It is based on information that originated in 2010 and was recently supplemented by further details relating to timing.

For a number of years now, Goodyear has been focussing intensively on the development of a tyre made from renewable biomass. For familiar reasons: mineral oil, which has been the main raw material used in the production of synthetic rubber up to now, is a resource that is unfortunately only available in finite amounts and is too precious to be used for heating purposes or to be worn off on roads around the world.

The tyre industry, which – according to a report in the online edition of the German news magazine Spiegel - has arrived in the post-petrochemical age, has realised this too. Its motto is: back to the roots, i.e. the tyres of the future will be supplied by Mother Nature again.

That is the plan, the noble aim. Natural rubber is only playing a minor role in this context, however. The plants that the scientists intend to harvest in order to manufacture car tyres are much smaller. What are involved here are extracts of dandelion or soy oil.

Whereas Continental is still reluctant to issue any specific statements about when it plans to introduce an “environmentally sound” car tyre, Bridgestone’s message is very clear; it has announced that it will be launching natural tyres in 2020 which will have a comparable property profile (i.e. rolling resistance, braking characteristics and road grip) to conventional tyres.

The American company Goodyear is stepping on the gas more than this: together with DuPont Industrial Biosciences, the US tyre manufacturer is working on the development of biobased isoprene, from which rubber can also be produced - without mineral oil. Current tests have evidently raised the company’s expectations, so that it anticipates the introduction of such new environmentally sound tyres in 2015. k-online wishes everyone involved great success in this project. GDeußing