Light-Controlled Phase Separation Using Different Monomer Compositions of a Radical/Cationic System
Erion Hasa, University of Iowa
Abstract:Photopolymerization-induced phase separation (PhIPS) is a technique capable of combining the properties of different constituents into a single polymer by controlling the polymer morphology. PhIPS leads to distinct nano/microstructured domains, generating materials with unique physical and mechanical characteristics. We investigated the effect of irradiation intensity on the morphology of polymers with different monomer ratios. Phase separation was induced by using a butyl acrylate (BA) and di-functional oxetane (DOX). The irradiation intensity had a small effect on the degree of phase separation for formulations with low concentrations of BA. On the other hand, the nano/microstructure domains were significantly dependent on the irradiation intensity for formulations with concentrations of BA on the same order as of DOX which resulted in higher modulus and up to a four-fold increase in toughness. These results demonstrate the ability to control the morphology and properties in photocurable systems through PhIPS.