Bridgestone makes tires from natural rubber
Bridgestone Corporation has taken a step forward in diversifying rubber sources announcing a new tire with 100 percent of natural rubber-containing components derived from guayule. Guayule is a plant native to the southern U.S. and northern Mexico. The natural rubber was cultivated at the company’s Biorubber Process Research Center in Mesa, Arizona.
There are about 2,000 plant species producing natural rubber, with the Hevea tree the most productive. But this isn’t the first time guayule has been used as an experimental alternative to traditional rubber. In the 1920s, the Intercontinental Rubber Company in California produced 1,400 tons of guayule rubber after leaf blight decimated the Brazilian rubber industry. Guayule also became a temporary replacement for Hevea tree-produced latex rubber during World War II, when Japan cut off America’s Malaysian latex supplies. However, that project ended after the war.
The war years were also responsible for the synthetic rubber industry. In order to meet the nation’s needs for the vital material, the government built synthetic rubber plants, operated by the industry. Synthetic rubber production jumped from 8,000 tons in 1941 to 820,000 tons in 1945. After the war, the government sold the plants to the industry. About 70 percent of rubber used today is synthetic.
Bridgestone says its guayule tires are a big step because guayule grows in arid regions, as opposed to the tropical climate of the Havea hrasiliensis rubber tree — the source of 90 percent of all natural rubber. Diversifying the climates where tire rubber can be produced could make a big difference to the sustainability of alternative sources. In those tires all of the tire’s major natural rubber components — including the tread, sidewall and bead filler — were replaced with natural rubber extracted from guayule grown and harvested by Bridgestone.
Tire demand is expected to increase along with global population growth and the increased motorization in developing nations. Natural rubber is the primary raw material used to produce tires worldwide. It’s consumed in large quantities and primarily produced in Southeast Asia. Bridgestone’s future research endeavors will focus on optimizing the natural rubber content in each guayule shrub, as well as evaluating applications in a wider range of tire types and rubber compounds.
Natural rubber from dandelion at Continental Corporation
Bridgestone isn’t the only firm experimenting. In June Continental Corporation’s research on the Russian dandelion led to a car tire prototype based on dandelion rubber.
“In agricultural terms, it is an undemanding plant, even in the northern hemisphere, and can be cultivated on land not suitable for food production,” said research team leader Carla Recker. “This means that rubber production is conceivable near our tire factories, for instance, and the significantly shorter transport routes would also reduce carbon dioxide emissions.”
Back in 2010, Continental issued a statement that it was aiming to produce a tire that reduced fossil fuel products by 90 percent. Continental’s head of material evaluation and processing car and truck tires Boris Mergell said the company was focusing on polymers made from biomass, process oils, different types of carbon black, mineral nano fillers and, in particular, recycled materials.
Yokohama’s orange oil tires
Including natural components in tire production is by no means new. Yokohama has added orange oil to tires for 20 years. It is used in racing tires to help keep them sticky for more laps. It is also used to create an “ecofriendly” consumer tire. The oil replaces only a small part of the petroleum products used in tire manufacture, but it also increases the longevity of the tire.