Cleveland, Ohio – Lubrizol has introduced a prototype 100% TPU recyclable shoe.
The company claims it meets the high-performance demands in the footwear industry, while achieving greater sustainability through enhanced recyclability.
The shoe is made using the company's TPUs yarns to keep the construction light in weight. BounCell TPU foam is used for cushioning, and Estane TRX thermoplastic polyurethane is the abrasion-resistant outer material.
Like other polyurethane applications, using TPU helps to glue the shoe together during production. This can simplify production by removing gluing steps, and also make it easier to automate the production process.
The thermoplastic nature of the polyurethanes makes it much simpler for the footwear producers to recycle in-process waste back into the production stream. This saves emissions from the traditional way of dealing with in process scrap: incineration, said Lubrizol.
As well as being recyclable in production, and in principle at the end of the product's life, the polyurethanes used to make the shoes contain a significant proportion of bio-based or renewable raw materials.
Estane ECO TPU outers are derived from natural resources, and deliver the same mechanical physical and chemical performance properties as conventional TPUs, Lubrizol said. The grades are also between 5% and 10% less dense than equivalent petrochemical grades, and offer the same hardness. The TPU resists yellowing as well, said the company.