Rubber - Properties, Development, Tyres, Earthquake Protection Systems and Recycling

Topics Covered

Background

Rubbers Blend of Properties

History and Development of Rubber

Rubber and Tyres

Recycling of Tyres

Rubber in Earthquake Protection Systems for Bridges and Buildings

Summary

Background

With its distinctive tactility and unique smell, rubber is a veritable feast for the senses, providing idiosyncrasy and the potential for design ingenuity in equal measures. Its influence ranges from the practical to the aesthetic, the functional to the fun, and it is finding increasing application in projects characterised by their environmentally-sound objectives, a move that is placing the material at the forefront of contemporary eco-friendly design.

Rubbers Blend of Properties

Rubber's physical flexibility seems to be a nod to its amazing versatility. Its durability, elasticity mouldability and waterproof properties have made rubber the material of choice for end users ranging from tyre manufacturers and sportswear designers, to Hollywood special effects creators and fetishists even. Marks and Spencer is in on the rubber scene, having recently used barasol, a type of rubber, as the basis of its new head office furniture.

History and Development of Rubber

In terms of the material’s history, natural rubber originally derived from the rubber tree (hevea brasiliensis) in South America, and it has been used there for thousands of years. It was only recently that English chemist Joseph Priestly coined the term ‘rubber’ in 1770 upon discovering its erasing capabilities. In the years that followed, while designers could foresee that rubber’s impressive physical properties could be harnessed in terms of possible applications, there remained no way to make it viable for manufacturers.

Only in 1839 that Charles Goodyear patented sulphur as a stabilising agent during the processing of rubber, and vulcanisation was born.

Rubber and Tyres

In addition to rubber bands and rubber ducks, one of the first things we associate with this material is the humble tyre. Initially invented for tricycles by John Boyd Dunlop in the late 19th century, tyre manufacturing took off in a major way with the invention of the motor car, and commercial rubber production has since gone through the roof. However, in recent years this has caused a major concern for environmental groups.

Recycling of Tyres

But while in its natural state the material is biodegradable, the extensive processing that it undergoes (tyres use rubber mixed with synthetic substances such as plastics and chemical curatives to ensure that, when cars reach high speeds, ‘burning rubber’ is a theoretical description rather than a frightening reality) renders rubber much more durable, and is therefore a major recycling problem. One group that is currently attempting to address the threat of endless ‘tyre mountains’ is Earthship, USA. The organisation uses local reclaimed materials to construct environmentally friendly housing that does not use fossil fuels and is completely self-sustainable. Earth-rammed tyres are used for the foundations of the housing’s walls, and are then consolidated with straw bale and finally rigid insulation to stabilise the comfort of the interior space. Another company, Remarkable, UK, is adopting a similar attitude to reuse, albeit on a slightly smaller scale. Everything it designs and manufactures from stationery to handbags, comes from identifiable recycled or sustainable resources. The company transforms rubber tyres from having a purely practical original existence to playing an integral part in the aesthetic appeal of a product.

Rubber in Earthquake Protection Systems for Bridges and Buildings

Dynamic Isolation Systems (DIS), USA, while not overtly marketing itself as motivated by altruistic environmental concerns, is nonetheless making great use of synthetic rubber’s capacity for extreme longevity, and in doing so, is helping to ensure that the material it uses will not crowd landfill sites in years to come. The company is responsible for matching earthquake protection systems to the specific needs of individual structures, and relies on rubber’s long shelf life to form a stable (and energy dissipating) base to these kind of isolation units. Vulcanised rubber layers that can move in any horizontal direction are laminated between steel sheets to form a moveable, flexible base, with a cylinder of pure lead tightly inserted through a hole in the middle. The rubber layers allow the isolator to easily displace sideways, providing lateral flexibility that ensures the building or bridge returns to its original position after the shaking has stopped. In this way, synthetic rubber’s long lasting qualities are used to safeguard the existence not just of the structure, but also its inhabitants.

Summary

Jeanne Silverthorne, an American artist, uses rubber as the source of her sculptures because she believes that it conveys the parallelism that exists between the gradual decay of the material and our own transient existence. It is therefore interesting that companies and organisations such as those mentioned above are reversing this trend, and instead making use of rubber’s longevity to maximise, or make the most out of, the life of the materials they deal with. They are doing their bit to ensure that our lives are not cut short through lack of consideration for - or, in the case of DIS, lack of understanding of - the environment. Like rubber, we want to take on the pressures of existence and bounce back time and time again.

 

Source: Materials World, Vol. 12, No. 7. pg. 20, July 2004.

 

For more information on this source please visit The Institute of Materials, Minerals and Mining.

 

Date Added: Jul 6, 2004 | Updated: Jun 11, 2013
Tell Us What You Think

Do you have a review, update or anything you would like to add to this article?

Leave your feedback
Submit