Hybrid Organic–Inorganic\nComposites Based on\nGlycolyzed Polyurethane

Abstract

We present a simple approach to upcycle\nglycolyzed polyurethane\nfoam products by fabricating robust, highly filled organic/inorganic\ncomposites (46–60 wt % solid loading). These composites, consisting\nof recycled polyols, naturally occurring or synthetic aluminosilicate\nminerals, and isocyanate linkers, are shown to possess superior mechanical\n(flexural) properties compared to ordinary Portland cement (OPC).\nOptimization of chemical composition (isocyanate and inorganic content)\nand curing temperatures (25–50 °C) results in low-density\ncomposites (up to 3× less dense than OPC) with flexural strengths\ncomparable to OPC while exhibiting strain capacities up to 5×\nas compared to OPC-based systems. In contrast, parallel fabrication\napproaches using low OH-value virgin polyols resulted in flexible\ncomposites and much lower flexural strengths, highlighting the advantage\nof employing high −OH density recycled polyols. Variations\nin the flexural strength of the composites were correlated with differences\nin their morphologyuniformity in the distribution of inorganic\nparticles contributed to improved flexural properties. The generality\nof this fabrication approach is demonstrated using quartz sand as\nthe inorganic particle and recycled polyols with different hydroxyl\nvalues.