• Use of CO2 and biomass as raw materials
  

• Plastic waste as a valuable resource
  

• Low-solvent coatings and adhesives
  

Both shoes feature Covestro products derived from alternative raw materials such as CO2, biomass and plastic waste. These are a valuable resource as they provide carbon that can be put to use beneficially in a circular economy, instead of being released into the atmosphere as waste gas. Covestro is pioneering the use of such raw materials to reduce its dependence on fossil materials and increase the sustainability of the value chain.

Walking with CO2 technology

One example is the upper and inner lining of the two shoes. The base is a soft foam that ensures a good fit and comfortable footfall. Here, a precursor product was used that contains up to 20 percent carbon dioxide and is marketed by Covestro under the name cardyon®. The CO2 replaces some of the fossil raw materials previously used, but does not compromise the favorable properties of conventionally produced foam.

Two different types of thermoplastic polyurethane (TPU) are found in the outer soles of both women's shoes. One of them is also based on cardyon®; while in the other, 60 percent of the carbon content is derived from biomass. As a result, both products have a lower CO2 footprint than fossil-based TPU and help close the carbon cycle.

High heels made from recycled plastic

Covestro is also focusing on the recovery of plastic waste as part of its strategic program to support the circular economy, and is working with partners to develop new value-adding cycles to achieve this. For example, used polycarbonate products are shredded, cleaned, possibly mixed with new plastic and reused as recycled Makrolon®. In women's shoes, this lends lasting strength to the insole and heel.