EVA (ethylene-vinyl acetate) is the rubbery wonder material that sneaker designers worldwide rely upon for midsoles and outsoles: It's lightweight, soft, shock-absorbing, moldable, crack- and UV-resistant, and can be dyed any color you wish.
The problem with EVA is that there's no widespread and practical way to recycle the stuff, and it doesn't biodegrade. Spent sneakers generally wind up in landfill.
To combat this, footwear brand TOMS has announced they're switching to a bio-based EVA (clunkily-named "I'm green™ EVA") made from sugarcane. According to manufacturer Braskem, a petrochemical company that describes themselves as the world's leading biopolymer producer, the sugarcane-derived material is far greener than the petroleum-derived variety:
"I'm green™ bio-based EVA is made from biofuel obtained from sugar cane. This highly efficient crop is carbon-negative: Sugar cane consumes CO2 and extracts clean oxygen. I'm green™ bio-based EVA is the first earth-friendly alternative to conventional EVA that also offers the same comfort and longevity."
The bio-based EVA will first be used in TOMS' Earthwise line of footwear, which already feature plant-dyed canvas uppers.