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Tunable Chiroptical Switching via 2-Fold Chiral Conflict in Statistical Racemic Copolymer Assemblies
Zixiang He1,2, Xingyue Yuan2, Haotian Ma2
1College of Chemistry, Zhengzhou University, Zhengzhou 450001, China.
ACS Macro Letters
|October 16, 2025
Summary
Researchers created chiral racemic copolymers with switchable chiroptical activity using a novel 2-fold chiral conflict self-assembly strategy. This method mimics natural homochirality development and offers new possibilities for chiral polymer nanoassemblies.
Area of Science:
- Polymer Chemistry
- Supramolecular Chemistry
- Chirality Studies
Background:
- Chiral communication is vital for homochirality in nature.
- Polymers from racemic mixtures typically lack chiroptical activity.
Purpose of the Study:
- To develop a method for creating global chirality in statistical racemic copolymers.
- To enable switching of chiroptical activity in these polymers.
Main Methods:
- Utilized a stepwise statistical polymerization-induced chiral self-assembly (stat-PICSA) method.
- Constructed chiroptically active assemblies from racemic building units within heterochiral segments.
Main Results:
- Achieved global chirality in statistical racemic copolymers.
- Demonstrated switchable chiroptical activity by altering monomer ratios.
- Observed distinct chiral conflict effects: "first come, first served" (FF) and "late-comer lives above" (LA).
Conclusions:
- The 2-fold chiral conflict self-assembly strategy provides a unique approach for chiral racemic polymer nanoassemblies.
- This strategy deepens the understanding of homochiral structure origins in nature.
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