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Side-Chain Control of Topochemical Polymer Single Crystals with Tunable Elastic Modulus
Zitang Wei1, Xiaokang Wang2, Bumjoon Seo1
1Davidson School of Chemical Engineering, Purdue University, West Lafayette, IN 47907, USA.
Angewandte Chemie (International Ed. in English)
|October 11, 2022
Summary
Researchers engineered side chains for bis(indandione) derivatives, enabling topochemical polymerization into high-performance polymer single crystals. This method enhances material properties and allows processing into robust thin films.
Area of Science:
- Materials Science
- Polymer Chemistry
- Crystallography
Background:
- Topochemical polymerization offers a route to high molecular weight, stereoregular crystalline polymers.
- Monomer modification can disrupt crystal packing, leading to non-reactive polymorphs, hindering polymerization.
Purpose of the Study:
- To systematically study side chain functionalization in bis(indandione) derivatives for controlled topochemical polymerization.
- To optimize monomer design for enhanced reactivity, mechanical properties, and processability of polymer single crystals.
Main Methods:
- Synthesis of bis(indandione) derivatives with systematically varied side chains.
- Visible light-initiated polymerization of monomer single crystals.
- Characterization of polymer crystal structure and mechanical properties.
- Ultrasonication for processing insoluble polymer single crystals into thin films.
Main Results:
- Engineered side chains successfully directed monomer crystallization for sustained topochemical reactivity.
- Optimization of side chain length and end groups significantly enhanced the elastic modulus of polymer single crystals.
- Insoluble polymer single crystals were processed into free-standing, robust thin films via ultrasonication.
Conclusions:
- Molecular design of side chains is crucial for controlling topochemical reactivity and material properties.
- This approach enables the production of high-performance polymer single crystals with tunable characteristics.
- The developed method opens avenues for advanced applications of crystalline polymers.
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