Development of Novel Phase-Change Materials Derived from Methoxy Polyethylene Glycol and Aromatic Acyl Chlorides

In this research, novel, organic, solid-liquid phase-change materials (PCMs) derived from methoxy polyethylene glycol (MPEG) and aromatic acyl chlorides (ACs) were prepared through a condensation reaction. The MPEGs used as functional chains with different molecular weights (350, 550, 750, 2000, 5000 g/mol). ACs, terephthaloyl chloride (TPC) isophthaloyl (IPC), employed bulky linker cores. Solubility tests demonstrated that family of PCMs is soluble in protic polar solvents such H2O MeOH, insoluble nonpolar n-hexane. Fourier-ransform infrared spectroscopy (FT-IR UATR) nuclear magnetic resonance (1H, 13C, DEPT 135°, COSY, HMQC, HMBC NMR) to confirm the bonding MPEG ACs. crystalline morphology synthesized was examined using polarized optical microscopy (POM), revealing formation spherulites Maltese-cross-extinction patterns. Furthermore, it confirmed higher at room temperature exhibited an increased average spherulite size compared their precursors. Thermal stability conducted thermogravimetric analysis (TGA) indicated decomposition temperatures close 400 °C for all PCMs. properties characterized by differential scanning calorimetry (DSC), novel melted crystallized between −23.7 60.2 −39.9 45.9 °C, respectively. Moreover, heat absorbed released ranged 57.9 198.8 J/g 48.6 195.6 J/g, Additionally, thermal after undergoing cycles melting-crystallization, indicating energy absorption release occurred nearly constant temperatures. This study presents new high-performance organic demonstrates orientation substituent groups phenylene ring influences supercooling, transition temperatures, storage capacity depending on weight.