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Orientational Transition in a Liquid Crystal Triggered by the Thermodynamic Growth of Interfacial Wetting Sheets
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A Recyclable Polythioester With α-Gem-Dimethyl Substitution: Instantaneous Crystallization Triggered by Large and
Chun-Yan Lyu1, Wei Xia1, Tianyi Ma2,3
1Beijing National Laboratory for Molecular Sciences, Center for Soft Matter Science and Engineering, Key Laboratory of Polymer Chemistry and Physics of Ministry of Education, College of Chemistry and Molecular Engineering, Peking University, Beijing, People's Republic of China.
Advanced Materials (Deerfield Beach, Fla.)
|February 5, 2026
Summary
Researchers developed a recyclable polythioester (PTE) that crystallizes rapidly under stretching, yielding strong, transparent fibers. This breakthrough offers a new pathway for high-performance sustainable materials.
Area of Science:
- Materials Science
- Polymer Chemistry
- Crystallography
Background:
- Developing recyclable polymers with high mechanical performance is a significant challenge in sustainable materials.
- Controlling polymer crystallization is key to achieving both recyclability and desirable mechanical properties.
- Depolymerizable polythioesters (PTEs) offer potential for sustainable materials but require optimized processing.
Purpose of the Study:
- To investigate the crystallization behavior of a novel depolymerizable polythioester (PTE), PaGMTE.
- To explore methods for enhancing the crystallization rate and mechanical properties of PaGMTE.
- To determine the crystal structure of PaGMTE and understand its crystallization mechanism.
Main Methods:
- Organocatalytic ring-opening polymerization of α-gem-dimethyl-β-thiolactone to synthesize PaGMTE.
- Controlled rapid stretching experiments (strain ~600%, strain rate ≥ 10 s-1) to induce crystallization.
- X-ray diffraction and electron microscopy to analyze crystal structure and morphology.
- Mechanical testing to evaluate the properties of the stretched fibers.
Main Results:
- PaGMTE exhibits exceptionally slow quiescent crystallization but rapid crystallization (> 200,000 fold acceleration) under large-amplitude stretching.
- Stretching achieved ~40% crystallinity within 1 second, producing highly oriented fibers with excellent mechanical properties (Young's modulus 0.80 GPa, tensile strength 120 MPa) and high transparency.
- The orthorhombic crystal structure (space group P212121) of PaGMTE was determined, revealing antiparallel-packed homochiral 83 helices, attributed to entropic barriers.
Conclusions:
- Rapid stretching is an effective strategy to overcome slow crystallization kinetics in PaGMTE, enabling high crystallinity and performance.
- The unique crystal structure and crystallization behavior highlight the significant impact of sulfur substitution in polymers.
- PaGMTE demonstrates potential as a high-value, recyclable material through controlled crystallization, advancing sustainable polymer development.
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