Enabling Circularity and Upcycling of Post-Consumer-Use Flexible Polyurethane Foam

Of the 15 million metric tons of polyurethane (PU) waste generated annually in the US, flexible PU foam accounts for ~30%. Mattresses comprise 40% of the PU flexible foam market; nearly 50,000 mattresses are discarded daily in the US and each year, 20 million mattresses end up in landfills. Mattresses comprise flexible PU foam layers (memory foam, support foam) with varying chemical compositions (extent of cross-linking or foaming). An absence of comprehensive and easy strategies to classify these layers limits the thorough recycling and appropriate disposal of post-consumer flexible PU foam. To address this challenge, an inexpensive and field-employable strategy correlating observable physical properties to the chemical composition and thermo-mechanical properties of these foams will be shown. This will aid industrial recycling strategies tailored to post-consumer-use flexible PU foam layers.

While post-consumer-use flexible foams are seldom recycled, chemical recycling strategies exist for post-industrial foams (glycolysis, acidolysis, hydrolysis). However, they yield polyols with high functionality, branching, and undesirable color, thereby limiting their utility to only partial replacements (<40 wt%) for virgin feedstock. In this work, a simple one-pot strategy has been developed and optimized to upcycle them in the fabrication of high-strength organic/inorganic composites, with sound attenuation and thermal insulation properties superior to conventionally employed materials.