Title

Thiol-ene Photopolymerization Kinetics of Vinyl Acrylate/Multifunctional Thiol Mixtures

Document Type

Article

Publication Date

5-18-2004

Department

Polymers and High Performance Materials

Abstract

The photopolymerization of multifunctional thiol (trimethylolpropane tris(3-mercaptopropionate))/vinyl acrylate mixtures as a function of thiol content in the presence and absence of photoinitiators has been investigated using real-time FTIR, thin-film calorimetry, and 2D-COSY NMR. The addition of a multifunctional thiol to vinyl acrylate significantly enhances the conversion of the vinyl double bonds of vinyl acrylate due to the preferential addition of the thiyl radical to the vinyl group. Two separate free-radical polymerization processes, acrylate homopolymerization and thiol/vinyl ester copolymerization, occur simultaneously in thiol/vinyl acrylate mixtures. Thin-film calorimetry and 2D-COSY NMR results are consistent with real-time FTIR results, giving strong evidence for two simultaneous free-radical processes.

Publication Title

Macromolecules

Volume

37

Issue

10

First Page

3606

Last Page

3613