Old Tires Become Timberland Boot Soles

by Michael Smith

Timberland is putting waste tires back on the streets this year when it releases boots and shoes made with recycled tire rubber.

The material comes from Green Rubber, a Malaysian company that has developed a method for devulcanizing waste tires. Many rubber products like car tires, bumpers and shoe soles are made of vulcanized rubber, which is created by adding sulfur and heat to virgin rubber in order to make a tougher, more durable material.

Vulcanized rubber, though, is extremely difficult to recycle. Green Rubber has found a way around that, with its DeLink reactant, a proprietary mixture of chemicals that breaks the sulfur bonds in rubber and makes it recyclable. Tires must first be shredded into crumbs for the reactant to fully work, and Green Rubber offers the resulting product either as 100 percent Green Rubber compound or a 50/50 mixture of Green Rubber compounds and virgin rubber.

Timberland, which is the first company to commercially use Green Rubber in footwear, is slapping the 50/50 blend on the bottoms of 200,000 pairs of shoes in its fall 2009 collection. Nearly all of the footwear in its Earthkeepers line will have soles made with Green Rubber, and it will also be used on some boots outside of the Earthkeepers heading, primarily in men's rugged casual products, not in construction boots or high-end dress shoes.

Pete Lankford, a senior product designer at Timberland, said the company went with the 50/50 blend instead of the 100 percent recycled because of a very slight health concern.

"Car tires, which are the primary source for Green Rubber recycled material, are made with a variety of chemicals," he said. "One is within the rubber compound itself and through the life of the tire it off gases. There have been some concerns about the health effects on people who have continued and prolonged direct exposure to the chemical. Reducing the amount of recycled tire material to 50 percent in the Green Rubber compound we use eliminates this concern and allows us to offer a product that is both safe and green."

When shoes made with Green Rubber wear out, the soles can be reused by the Green Rubber company and recycled again, and Timberland is working on a plan for how to take back and disassemble boots.

It is a shame though that Timberland, while the 50/50 blend soles are better than nothing, is not going to use a full 100 percent product.

Also there are other companies, aside from the Malayan one quoted, such as some British ones, that recycle rubber tires into new rubber products and, though I have no knowledge of it as yet, I should think that soles for shoes and boots would not out of their league either.

If a method like that that was used years ago with military footwear then soles could be made and screwed on to the shoes and boots and could, thus, also be replaces. But, let's not go too green, I guess.

We must also remember that in the Third World rubber tires are used as soles directly and for the making of the sandals that were once upon a time referred to as Jesus sandals and which were the favorite footwear of the old Hippies.

© M Smith (Veshengro), 2009