Synthesis of High Molecular Weight Polystearylacrylate and Polystearylmethacrylate Polymers via ATRP Method as Thermal Energy Storage Materials

Derya Kahraman Doguscu, Cemil Alkan

In this study, poly(stearyl acrylate) (PSA) and poly(stearyl methacrylate) (PSMA) homopolymers were produced via atom transfer radical polymerization (ATRP) method from stearyl acrylate (SA) and stearyl methacrylate (SMA) monomers. Fourier transform-infrared (FT-IR) and proton nuclear magnetic resonance (1H-NMR) spectroscopy techniques were used for structural characterization as thermal energy storage characteristics and thermal stability property were determined by using differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) techniques respectively. The average onset phase transition temperatures of the PSA were measured as 48.1 and 43.5 °C as those of PSMA were measured as 30.8 and 23.5 °C respectively. The averages of latent heats of phase transitions were 100.2 and -81.5 J/g for PSA and 55.8 and -44.8 J/g for PSMA respectively. In addition, PSA and PSMA were found thermally durable up to considerably high temperatures compared to possible ambient temperatures. Molecular weight analysis measurements were performed using gel permeation chromatography (GPC) and number average molecular weights of synthesized polymers was found in the range of 58000-439000 g/mol. Based on the results, PSA and PSMA polymers are potential materials for thermal energy storage applications.