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Blending as a Strategy to Attain Chiro-Optically Activity Polymers
Ana Paula Glislere1, Denis Turchetti1, Bruno Nowacki1
1Chemistry Department, Paulo Scarpa Polymer Laboratory (LaPPS), Federal University of Parana, Curitiba, Parana, 81531-990, Brazil.
Macromolecular Rapid Communications
|May 3, 2021
Summary
Pure polymers lack chiro-optical activity. However, blends with achiral polymers exhibit strong activity due to stable supramolecular structures, suggesting morphology control for active polymers.
Area of Science:
- Polymer Science
- Supramolecular Chemistry
- Chiroptical Spectroscopy
Background:
- Chiroptical properties are crucial for advanced material applications.
- Pure polymers with and without chiral centers often lack inherent chiroptical activity.
- Understanding structure-property relationships in polymer blends is essential.
Purpose of the Study:
- To investigate the chiroptical properties of polymer blends composed of chiral and achiral copolymers.
- To determine the origin of chiroptical activity in these blends.
- To explore the role of supramolecular morphology in inducing chiroptical behavior.
Main Methods:
- Synthesis of chiral and achiral copolymers.
- Preparation of polymer blends with varying compositions.
- Circular dichroism (CD) spectroscopy analysis.
- Morphological characterization of supramolecular structures.
Main Results:
- Pure chiral and achiral polymers showed no chiroptical signal in CD spectra.
- Blends with achiral polymers as the major component displayed significant chiroptical activity.
- This activity originated from stable supramolecular structures, independent of blend composition.
- The number of chiral supramolecular structures varied with blend composition.
Conclusions:
- Supramolecular morphology is a key factor in achieving chiroptical activity in polymers.
- Designing stable supramolecular structures offers a viable strategy for creating chiroptical polymers.
- Blend composition influences the quantity, not the nature, of active supramolecular assemblies.
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