Influence of Lithium Bistriflimide on Photopolymerization Kinetics and Properties of Crosslinkable Polyethylene Glycol Monomers

Influence of Lithium Bistriflimide on Photopolymerization Kinetics and Properties of Crosslinkable PEG Monomers

Valerie R. Levine, John W. Whitley & Jason E. Bara

Abstract:

Coordinated ionic liquids (IL) monomers allow for the possibility of new opportunities to create polymer materials with large inorganic fractions. These are a means of tailoring material properties and developing resins for photocuring-based 3-D printing. Our prior work focused on coordinating IL monomers formed from methyl methacrylate (MMA), 1-vinylimidazole (Vim) and other small molecules with lithium bistriflimide (LiTf₂N). Tf₂N anions are delocalized, bulky and weakly coordinating. This allows for the large solubility of LiTf₂N in these polymerizable polar organic species. Results show the presence of LiTf₂N accelerates photopolymerization rates as along with improving monomer conversion and yielding polymers with larger MW values. We have recently extended this work to crosslinkable species such as poly(ethylene glycol) diacrylate (PEGDA) and 1,6-hexanediol diacrylate (HDDA). This presentation will discuss polymerization behaviors of these crosslinkable species in the presence of LiTf₂N and the properties of the resulting networks, such as swelling behaviors in H₂O and DMSO.