Monomers are small molecules that are chemically bonded to other monomers, oligomers or polymers to form new polymers. Monomers employed in photopolymers and radiation-cured compositions are mostly acrylates or metahcrylates. They can be monofunctional or multifunctional. They may be used as crosslinkers or diluents.
Examples of monofunctional monomers include acrylic acid, methacrylic acid, hydroxyethyl acrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate, isodecyl acrylate, N-vinyl pyrrolidone etc. Multifunctional monomers include trimethylolpropane triacrylate (TMPTA), ethoxylated TMPTA, trimethylolpropane trimethacrylate, hexanediol diacrylate etc.