SYNTHESIS, CHARACTERIZATION, AND UV CURING OF ACRYLATE FUNCTIONAL HYPERBRANCHED POLYESTER RESINS

A series of different hyperbranched aliphatic polyester resins with acrylate functionality have been synthesized, characterized, and UV cured. The terminal groups have been either benzoates, propionates, or hydroxyls. The glass transition (T-g) and viscosity of the resins have been shown to depend on the polarity of the end groups. The increase in viscosity, while the propionate functional resin has the lowest T-g and viscosity. The acrylates are all free radically UV cured with little or no oxygen inhibition found. The residual unsaturation in the cured films is not detectable with Raman spectroscopy, i.e., less than five percent. The cured films are all hard with a T-g difference varying with the structure of terminal groups in the resins.