Photocurable polythiol based (meth)acrylate resins stabilization: New powerful stabilizers and stabilization systems

Photocurable thiol-ene formulations have tendency to undergo premature dark polymerization leading to a reduced pot-life and therefore only limited applications can be envisaged with these systems. New stabilizers and stabilization systems were experimented through thermal stability and photoreactivity studies. The experimental results highlighted their superior stabilization efficiency regarding photocurable thiol-(meth)acrylate resins. A stabilization system composed of lauryl gallate and triphenylphosphite showed excellent stabilization efficiency with enhanced photoreactivity of the thiol-(meth)acrylate resin and preserved thermo-mechanical properties of the photocured resin. Beyond the scope of stabilization of the target thiol-ene systems, lauryl gallate and triphenylphosphite can be envisaged as efficient stabilizers for other polymers against light ageing thanks to their friendly chemical nature. Origins and existing solutions in the art as regard to this stability issue are also discussed.