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Updated: Jul 24, 2025
11:17
Synthesis of Programmable Main-chain Liquid-crystalline Elastomers Using a Two-stage Thiol-acrylate Reaction
Published on: January 19, 2016
21.9K
Mechanochromism and Strain-Induced Crystallization in Thiol-yne-Derived Stereoelastomers
Virginia C Ritter1, Samantha M McDonald1, Andrey V Dobrynin2
1Department of Chemistry, Duke University, Durham, NC, 27708, USA.
Advanced Materials (Deerfield Beach, Fla.)
|July 3, 2023
Summary
This study reveals how stretching elastomers can activate molecular reporters, linking macroscopic material behavior to molecular changes. These findings enable the development of recyclable, strain-sensing polymers with tunable properties.
Area of Science:
- Materials Science
- Polymer Chemistry
- Mechanochemistry
Background:
- Elastomers exhibit strain-induced crystallization (SIC) under tension, transitioning from strain-hardening to SIC.
- Mechanophore activation in polymers is linked to stretching, suggesting a potential interplay with SIC.
Purpose of the Study:
- To investigate the relationship between strain-induced crystallization (SIC) and mechanophore activation in novel stereoelastomers.
- To develop recyclable, strain-sensing polymers by incorporating spiropyran mechanophores.
Main Methods:
- Synthesized thiol-yne-derived stereoelastomers covalently doped with spiropyran (SP) mechanophores.
- Performed uniaxial tensile tests and analyzed mechanochromism and SIC correlations.
- Investigated strain-rate-dependent mechanophore activation and reversion kinetics.
Main Results:
- SP-doped elastomer properties were consistent with undoped controls, with SP acting as a mechanical state reporter.
- Mechanochromism correlated with SIC in a strain-rate-dependent manner.
- Activated mechanophores remained in a force-activated state post-stress removal, with tunable reversion rates.
Conclusions:
- The study establishes a link between macroscopic SIC and molecular mechanophore activation in elastomers.
- The developed polymers are recyclable and show potential for strain-sensing, morphology-sensing, and shape-memory applications.
- Tunable mechanophore reversion kinetics offer precise control over material response.
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