Combining Oxiranes and Oxetanes to Enhance Kinetics and Improve Physical Properties

Sara Kaalberg, University of Iowa

Abstract: Cycloaliphatic epoxides typically polymerize more slowly than acrylates and tend to be brittle. However, cationic active centers are long-lived, resulting in significant dark cure. Here, oxetane addition to formulations is correlated to improvements in polymerization kinetics and polymer properties during dark cure. Raman spectra yielded conversions; DMA provided Tg and crosslink density. Increasing oxetane concentrations improved epoxide conversion and drastically lowered Tg of the resulting polymers, thereby increasing the application range for cycloaliphatic epoxides.