Photoinitiatorfree photopolymerization of acrylatebismaleimide mixtures and their application for inkjet printing

There is growing interest in using photoinitiatorfree systems in coating applications such as inkjetprinting, because residual photoinitiator can alter the properties of the resulting polymer. Bismaleimides (BMI) offer the opportunity to polymerize acrylates without the addition of photoinitiators, as this class of molecules can serve both as polymerizable monomer and as photoinitiator together with electron donor systems, like vinyl ether monomers or acrylates. The UVinduced copolymerization of a lowmolecularweight BMI with various acrylate monomers and oligomers without any photoinitiator was characterized. The BMIacrylate systems show comparable polymerization speeds to widely used acrylic systems with photoinitiator. Superior thermal stability as well as thermomechanical properties are achieved by enhancing acrylics with BMI. Such photoinitiatorfree systems lend themselves to be used for lowmigration coatings as well as for hightemperature applications. Here, a characterization of selected BMIacrylate mixtures regarding their photocuring kinetics and their application as inks for inkjet printing is shown.(VLID)361611