| Ultraviolet curing technology is a new curing technology with efficiency, energysaving and environmental. The UV curing process is a polymerization technique inwhich radiations induce a fast transformation of a liquid monomer into a solidpolymer. Its systems have been widely used in coatings, inks and adhesives, due to alot of benefits over conventional thermal curing systems such as rapid cure, lowenergyconsumption, high efficiencyand low VOC.New radical and cationic hybrid UV-curable polymer were synthesized frompolyurethane, epoxy acrylate and N, N-dimethylbenzylamine (DMBA) as a catalyst.Different UV-curable liquid compositions were developed with different oligomers,reactive diluents and photoinitiators (Irgacure 1173 and IHT-PI825). Thin films wereprepared by curing these composite solutions using a high pressure mercury lamp.The UV hybrid curing methods are perfect choice to make up for deficiencies incapability and synergistic effect of different single curing manner.The change of double bond, NCO group and epoxy group were identified byFourier Transform Infrared (FTIR) spectra during the process of UV-curing. Physical,mechanical and thermal characterizations of the UV-cured films were investigated.The gel content and volume shrinkage increased with increasing the number offunction group reactive diluent (BA, NPGDA and TMPTA) in the compositions, thephysical and mechanical properties of UV-cured films increased too, except for therelative elongation. It was found that the properties and thermal stability of hybridhigher than radical curing.The volume shrinkage rate and gel-content became smaller and smalleraccording to rise of the PEG molecular (200-4000). Adhesive force got better andbetter on substrate material. Toughness with the elongation upward curve got betterthan previously.
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