Enhancing the stability of UV‐curable thiol/vinyl carbonate resins

ABSTRACT In this study, the effect of various stabilizer systems on low‐cytotoxic thiol/vinyl carbonate formulations was evaluated with the aim to inhibit premature dark polymerization reactions. The addition of hydroxybenzene‐based radical scavengers such as pyrogallol (PyG), hydroquinone monomethyl ether (MEHQ), or butylated hydroxytoluene (BHT) resulted in a significantly decelerated increase in viscosity compared to formulations without stabilizers during a defined storage period at 50 °C. The usage of bicomponent stabilization systems in appropriate concentrations further reduced the viscosity increase for nonpigmented formulations. The most effective heterosynergistic stabilization system based on PyG and diisoctyl phosphonic acid (9 mM/90 mM) exerts only a minor influence on the polymerization performance, which was shown by photo‐DSC measurements. The herein presented stabilization of vinyl carbonate/thiol resins exhibits a significant contribution to bringing these low‐toxic building blocks into industrial applications. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44934.