Synthesis and characterization of poly(urethane)/silver composites via in situ polymerization

Abstract In this study, poly(urethane)/silver (PU/Ag) composites were synthesized in dimethylformamide (DMF) with no essential extra reducing agents. The reaction medium DMF is acting as both a diluent and reducing agent for silver particles. Composites (PU/Ag) were synthesized by in situ polymerization in the existence of different amounts of silver nitrate. The formation of PU/Ag composites was approved by ultraviolet–visible (UV–vis) spectrometer, Fourier transform infrared (FTIR) spectroscopy, and X‐ray diffraction (XRD) analyses, scanning electron microscopy–energy dispersive X‐ray (SEM–EDX) analyses, thermogravimetric analysis/differential thermal analysis (TGA‐DTA), and differential scanning calorimetry. The conductivity measurements of PU and composites were done with the four‐point probe technique using a Keithley 2400 electrometer. The conductivity values of the undoped PU, PU5, PU10, and PU20 were about 1.18 × 10⁻⁷, 2.2 × 10⁻⁶, 2.3 × 10⁻⁷, and 1.25 × 10⁻⁷ S cm⁻¹, respectively. The presence of silver particles was approved by UV–vis spectroscopy, EDX, and XRD. The formation of silver particles was determined by UV–Vis absorption spectra of the polymer matrix. According to TGA, it was observed that composites have higher thermal stability than polyurethane.