Ingrid Calvez1, Caroline R. Szczepanski2, Véronic Landry1

1) NSERC – Canlak Industrial Research Chair in interior Wood-Products finishes, Department of Wood and Forest science, Université Laval, Québec, Canada.
2) College of Engineering, Department of Chemical Engineering & Materials Science, Michigan State University, East Lansing, Michigan, USA.

Photopolymerization of radical and cationic system can generate new polymer networks named interpenetrating polymer networks (IPNs). Phase separation and final polymer morphology are governed by thermodynamic incompatibility and polymerization kinetics. Many factors can affect polymerizations kinetics such as monomer/oligomer viscosity and structure, light intensity, photoinitiator content and absorbance, cross-linking, vitrification, etc. Phase-separated system is a promising technique to generate self-matting UV-curable coating. It is possible to create surface roughness through phase separation and formation of multiple domains. This work describes the phase separation and demixing of incompatible macromolecular liquids creating microstructural phase heterogeneity and microphase separation of a radical/cationic hybrid system. The decrease in gloss can be controlled by polymerization kinetics and the formation of phase separated domains to achieve surface roughness. Phase separation morphologies, polymerization kinetics, final properties (e.g. gloss) are studied in function of the ratio of the acrylate/epoxy mixture and can be controlled by the photoinitiator content.