Ureidopyrimidone (UPy) functionalized high chain alcohols as potential organic supramolecular materials for thermal energy storage with quadruple hydrogen bonding

Reversible hydrogen bonding is a new approach for tailoring thermal energy storage in organic phase-change materials (PCMs). Herein, we present novel ureidopyrimidone (UPy)-based materials functionalized with aliphatic fatty alcohols, utilizing the UPy quadruple hydrogen-bonded core for tunable phase transitions. 1H NMR and FTIR analyses confirmed the hydrogen-bonded supramolecular architecture, while DSC revealed melting temperatures of 370.9–387.1 K (97.7-113.9 °C) and latent heats of up to 96.96 ± 0.70 J/g. Thermogravimetric analysis revealed a decomposition onset above 503 K (230°C), indicating robust high-temperature stability. The alkyl chain length effectively modulated the phase-change temperature without compromising the latent heat, highlighting the dominant role of the UPy core in energy storage. This study is the first to report UPy-functionalized building blocks as potential solid-liquid PCMs for high-temperature applications, providing a versatile approach for next-generation sustainable thermal energy storage.