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Constructing Thioether/Vinyl Sulfide-tethered Helical Peptides Via Photo-induced Thiol-ene/yne Hydrothiolation
Published on: August 1, 2018
Redox Initiation of Bulk Thiol-Ene Polymerizations
Megan A Cole1, Katherine C Jankousky, Christopher N Bowman
1Department of Chemical and Biological Engineering, University of Colorado, Boulder, Colorado, USA.
Polymer Chemistry
|April 9, 2013
Summary
Redox initiation enables thiol-ene click polymerization with advantages like unlimited cure depth and mild conditions, matching photochemical methods. Inhibitor levels precisely control polymerization rates and induction periods.
Area of Science:
- Polymer Chemistry
- Click Chemistry
Background:
- Thiol-ene "click" reactions are well-studied for photo- and thermal initiation.
- Redox initiation of thiol-ene polymerizations remains less explored, presenting a knowledge gap.
Purpose of the Study:
- To fully characterize redox-mediated thiol-ene polymerization.
- To investigate the influence of initiation systems, monomers, functionalization, and inhibitors.
- To confirm redox initiation's efficacy for achieving full conversion in small molecule systems.
Main Methods:
- Investigated redox-initiated thiol-ene polymerization kinetics.
- Varied initiation systems, monomer structures, functionalization degrees, and inhibitor concentrations.
- Analyzed network properties of resulting polymers.
- Examined the mechanism of quinone inhibition in the presence of aniline.
Main Results:
- Redox initiation achieved full conversion for small molecule thiol-ene systems.
- Polymerization rates for multifunctional thiol-ene systems were comparable to photo- and thermally initiated systems.
- Redox-initiated systems offered unlimited depth of cure and mild reaction conditions.
- Network properties were comparable to photocured materials.
- Inhibitor concentration controlled polymerization rate and induction period.
- Quinone inhibition mechanism was elucidated, showing dependence on aniline and inhibitor concentration.
Conclusions:
- Redox initiation is a viable and advantageous method for thiol-ene polymerization.
- This approach provides control over reaction kinetics and material properties.
- Understanding inhibitor mechanisms allows for fine-tuning polymerization processes.
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