Reactivity of dihydropyridines as reducing agents in redox initiating systems

For mild and ecofriendly polymerization conditions, Redox Initiating Systems (RISs) are more and more attractive. Indeed, the redox polymerization can be carried out at room temperature without any external energetic stimulus. Moreover, these latter processes can be very efficient under air and without purification of the monomers/resins. In this work, new redox initiating systems based on dihydropyridines are reported. An excellent reactivity is found in presence of copper complexes as catalyst, acid and peroxide. A full control of the gel time is possible by the selection of the appropriated reactant concentrations. These systems were characterized by optical pyrometry experiments as well as FTIR spectroscopy. Tack-free surfaces as well as potential photoactivation for on-demand polymerization can be obtained.