Polymer Bulletin, Vol.74, No.7, 2497-2511, 2017
Modification and characterization of urethane acrylate oligomers used for UV-curable coatings
Nine modified urethane acrylate oligomers including polyether-modified polyurethane acrylate, epoxy-modified polyurethane acrylate and hyperbranched polyurethane acrylate have successfully been synthesized and characterized by Fourier transform infrared spectra. The properties of UV-cured films formed by these oligomers were also investigated. The effects of the molecular structure of the oligomers on the properties of cured film, including tack-free time, pencil hardness, impact resistance, adhesion and boiling water resistance, have been discussed. The results indicate that the UV-cured film with good performance can be designed by the modification of the molecular structure of the oligomer. Among the oligomers prepared in this paper, the cured film formed using HBPUA-50% OA as oligomer exhibits a relatively short tack-free time, high hardness, good impact resistance, great adhesion and boiling water resistance.