Real time degradation studies on polyurethane household sponges in Danish weather and marine environments

Polyurethane (PUR) ether sponges represent a widely-used cleaning tool with a short service lifetime resulting in
the production of high quantities of waste. However, the fate of PUR in natural environments is poorly understood.
In this study, sponges were exposed to the natural environments of Danish weather and seawater for two
years. Physiochemical changes were monitored using visual, microscopic, spectroscopic and chromatographic
techniques. Results from Attenuated Total Reflection-Fourier Transform Infrared spectroscopy and change in
mass indicated that photo-oxidation was the primary degradation pathway of polyurethane ether- based sponges
with a specific surface degradation rate of 12,500 μm year􀀀 1 in Danish weather. Significantly, analysis by gas
chromatography–mass spectrometry showed the release to the environment of toxic substance TDI as a product
of photo-oxidation. Although PUR degraded more slowly in seawater than in weather, flame retardant TMCP
leached from sponges to water, indicating potential health risks of PUR waste to aquatic life.