Room temperature curing of acrylate-functionalized polyurethanes based on the solvent-free redox polymerization

In this work, we proposed an efficient redox initiating system (ROIS) for free radical polymerization of acrylate-functionalized polyurethanes (APUAs) at room temperature. In this ROIS, cumene hydroperoxide and aliphatic tetraethylenepentamine were used as the oxidizing agent and reducing agent, respectively. Fourier transform infrared spectroscopy results of APUAs and cured polymers show that this ROIS can enable both surface and inner curing of APUAs. The oxygen inhibition can be overcome by the reaction of tetraethylenepentamine with the hydroperoxide produced during the curing process in air atmosphere. The obtained polymer films show good transmittance, high crosslinking density (>86%), good thermal stability and suitable tensile strength (7.64 MPa), which can be applied in coating and adhesive industries. In addition, redox polymerization kinetic was studied by using differential scanning calorimetry.