Thermoacoustic Analysis of PEG-Ethanol-Epoxy- Nanoparticle Composite for Coating Applications across varying Temperatures

introduction: Polyethylene glycol (PEG), a hydrophilic polymer, is widely used in coatings due to its flexibility and chemical stability. The resulting system has tunable physicochemical properties when combined with epoxy resin and ethanol. Adding TiO₂ nanoparticles improves UV protection, thermal resistance, and mechanical strength. Optimizing coating performance requires an understanding of molecular interactions in such composites. A sensitive probe for assessing these interactions is ultrasonic analysis, which uses density, viscosity, and sound velocity measurements. In order to determine whether a PEG–ethanol–epoxy–TiO₂ nanocomposite is suitable for advanced coating applications, this study examines its thermoacoustic behavior at various temperatures. materials and methods: Without additional purification, PEG-6000, ethanol, epoxy resin, and TiO₂ nanoparticles (~30 nm) were employed. In ethanol, a composite comprising 2% TiO₂, 10% epoxy, and 5% PEG was created. An ultrasonic homogenizer (20 kHz, 30 hours) was used to disperse TiO₂. A 10 mL pycnometer was used to measure density, and an Ostwald viscometer was used to measure viscosity. At 4 MHz, ultrasonic velocity was measured between 25°C and 55°C. Standard equations were used to calculate the thermodynamic and acoustic parameters. results: The PEG–epoxy–TiO₂ composites density and viscosity dropped with temperature, suggesting a decrease in molecular cohesiveness. Ultrasonic velocity indicating reorganization of the structure. Temperature-dependent molecular interactions were validated by calculated parameters such as adiabatic compressibility and acoustic impedance. Additionally, surface tension decreased as temperature rose, promoting increased mobility and a decrease in intermolecular forces. discussion: Weakened intermolecular forces are indicated by the decrease in density and viscosity with temperature. At lower temperatures, TiO₂ nanoparticles improved molecular interaction; however, because of thermal agitation, their effectiveness decreased at higher temperatures. Changes in compressibility and structural dynamics are reflected in variations in ultrasonic velocity and derived parameters. The composites suitability for temperature-responsive coating applications is supported by these trends. conclusion: Strong molecular interactions in the PEG–epoxy–TiO₂ composite are confirmed by ultrasonic, density, and viscosity analyses. Good thermal adaptability is suggested by temperature-dependent changes in thermoacoustic parameters. Its potential as a responsive and effective material for advanced coating applications is supported by these findings.