Investigation of the Light Intensity and Temperature Influences on Double Bond Conversion in Resins for Vat Photopolymerization via Fourier Transform Infrared Spectroscopy

Abstract Herein, a systematic investigation of the effects of light intensity on double bond conversion in resins for vat photopolymerization is conducted and their mechanical properties are evaluated. For this aim, a urethane acrylate resin is synthesized and the structure is confirmed by means of NMR, IR, atmospheric pressure photoionization (APPI) and GPC. Photopolymer compositions based on it are studied. It is shown that an increase in light intensity resulted in a decrease in the double bond conversion for the transparent composition. An increase in temperature during photopolymerization led to an initial growth of double bond conversion, followed by a subsequent decrease. These findings are validated through bending and tensile strength analyses.