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Updated: Jun 4, 2025
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Synthesis of Programmable Main-chain Liquid-crystalline Elastomers Using a Two-stage Thiol-acrylate Reaction
Published on: January 19, 2016
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Base-catalyzed thiol-epoxy reactions: Energetic and kinetic evaluations
Belma Gjergjizi Nallbani1, Memet Vezir Kahraman1, Isa Degirmenci2
1Chemistry Department, Faculty of Science, Marmara University, 34722, Istanbul, Turkey.
Journal of Molecular Graphics & Modelling
|December 25, 2024
Summary
This study used quantum chemistry to investigate thiol-epoxide curing. Fluorine on thiols can extend curing time by reducing reactivity, enabling better control in industrial applications.
Area of Science:
- Polymer Chemistry
- Materials Science
- Organic Chemistry
Background:
- The thiol-ene/thiol-epoxide curing process is vital for material synthesis.
- Controlling reaction rates is crucial for industrial applications.
- Stronger base catalysts lead to uncontrollable, short curing periods.
Purpose of the Study:
- To investigate the mechanism of base-catalyzed thiol-epoxide curing.
- To identify initiators for controlled reaction rates.
- To understand factors influencing curing time and pot life.
Main Methods:
- Utilized quantum chemical tools for mechanistic investigation.
- Conducted kinetic and energetic studies.
- Analyzed the influence of initiator basicity and environmental polarity.
Main Results:
- Quantified the impact of initiator basicity on curing control.
- Demonstrated higher reactivity of terminal epoxy rings.
- Revealed autocatalysis due to changing environmental polarity during curing.
- Showed that fluorine substitution on thiols decreases thiolate anion nucleophilicity, extending application time.
Conclusions:
- Tertiary amines with low to medium basicity are suitable initiators for controlled thiol-epoxide curing.
- Environmental polarity changes contribute to autocatalysis.
- Incorporating electronegative atoms like fluorine onto thiols offers a strategy for prolonged curing application periods.
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