Footwear company Allbirds developed SweetFoam, said to be the world’s first green EVA. The material is introduced in the form of flip-flops.

EVA stands for ethylene-vinyl acetate, an elastic polymer that produces materials with a rubber-like softness and flexibility. Because of its squishiness, the material is popular to use for flip-flops and shoe soles. EVA is a petroleum-based material, for which there was no biobased alternative, until now.

SweetFoam is a carbon negative biobased EVA, made from sugarcane. Sugarcane is a highly efficient crop that grows in dense, rain-fed fields in Southern Brazil with minimal fertilizer. The material is processed in facilities that run entirely on renewable power, making the material the first carbon negative EVA.

Rather than keeping the material to themselves, Allbirds, a certified B Corp, will make the technology available to the entire footwear industry to promote green production. “EVA is one of the most widely used components in footwear, and this is the first time since its inception that it has been made from a renewable resource. After years of research, we are proud to introduce this into our products, and to the industry in a broad and meaningful way,” says Joey Zwillinger, co-founder of Allbirds.

Allbirds’ first product made from SweetFoam are the so-called Sugar Zeffers, inspired by Japanese-style flip-flops. The flip-flops consist of a contoured footbed and come with interchangeable straps, made from recycled polyester and plant-based microsuede made from sugarcane. The straps are filled with castor bean oil foam, and held together by biobased nylon anchors, also derived from castor bean oil.

Earlier, Allbirds introduced their sustainable woollen shoes and shoes made from eucalyptus tree, which you can read about here. However, according to Tim Brown, co-founder of Allbirds, “This was never about just wool or just shoes. There’s a bigger thing at play, there’s a bigger problem to solve, and I feel like with the introduction of SweetFoam we’re really gaining momentum around that.”

Photos: Allbirds