Reactive diluent effect on properties of UV‐cured films

Abstract

Abstract Polymer films were prepared with UV radiation from urethane acrylate oligomer (LR 8739) mixed with a photoinitiator (Irgacur 184) and a number of reactive diluents chosen from monofunctional monomers (such as N ‐vinyl pyrrolidone, ethylhexyl acrylate, methoxyethyl acrylate, and hydroxyethyl methacrylate), difunctional monomers (hexane dioldiacrylate, butanediol diacrylate, and tripropylene diacrylate), and a trifunctional monomer (trimethylol propane triacrylate). The optimum concentrations of the photoinitiator, oligomer, and diluents were determined. Various properties of the cured films such as pendulum hardness, gel content, swelling ability, tensile strength, and elongation at break were also determined. The glass transition temperatures ( T g ) of the diluents were correlated with tensile properties and those of the film. © 1994 John Wiley & Sons, Inc.