NIKE, Inc.
Methods for forming footwear using recycled plastics

Abstract:

Presented are manufacturing systems, methods, and devices for forming footwear using scrap or waste plastic materials. A method for manufacturing an article of footwear, such as an athletic shoe, begins with receiving a batch of recycled plastic, which may include thermoplastic elastomers or ethylene-vinyl acetate, and grinding the batch of recycled plastic material. The ground recycled material is processed, for example, by adding a foaming agent that activates at elevated temperatures. The processed recycled material is placed into the internal cavity of a final mold that is shaped like a segment of the footwear, such as a unitary sole structure. To form the footwear segment, the processed recycled material is heated past the threshold activation temperature of the foaming agent such that the foaming agent causes the recycled material to expand and fill the internal cavity of the final mold. The formed footwear segment is then extracted from the mold.