UV Curable Coatings: Effect of Diluents Concentrations on Double Bond Conversion and Rate of Photopolymerization

Abstract

Various formulations were prepared from the prepolymer, 2,2-bis-[4-(2-hydroxy-3-acryloxy prop-1-oxy)phenyl] propane with various functional diluents namely, di(ethylene glycol)ethylether acrylate, tri(ethylene glycol) dimethacrylate and trimethylolpropane ethoxylate (1-ethoxylate/hydroxyl) triacrylate in the presence of photoinitiator, 2, 2-dimethoxy-2-phenylacetophenone. These solutions were coated on the glass plates and then cured under ultraviolet radiation. The kinetics of photopolymerization, double bond conversion and rate of polymerization were studied by Fourier Transform Infrared Spectra. The results show that increasing irradiation time increases degree of conversion, whereas the rate of polymerization increases suddenly and then decreases.