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Published on: February 7, 2017
Photoinduced chirality in azobenzene-containing polymer systems
Suk-Won Choi1, Susumu Kawauchi, Na Young Ha
1Department of Organic and Polymeric Materials, Tokyo Institute of Technology, O-okayama, Meguro-ku, Tokyo, 152-8552, Japan.
Physical Chemistry Chemical Physics : PCCP
|July 12, 2007
Summary
Circularly polarized light (CPL) induces chirality in polymers with photochromophores. This phenomenon, observed in both side-chain and main-chain systems, has potential applications in optical devices.
Area of Science:
- Polymer Science
- Photochemistry
- Materials Science
Background:
- Chirality is a fundamental property in nature with significant implications in various scientific fields.
- Photochromic polymers offer tunable properties upon light irradiation.
- Understanding light-induced chirality is crucial for advanced material development.
Purpose of the Study:
- To review the mechanisms of circularly polarized light (CPL)-induced chirality in polymeric systems.
- To differentiate chirality induction in side-chain versus main-chain polymeric architectures.
- To highlight the potential applications of CPL-induced chiral polymers.
Main Methods:
- Review of existing literature on CPL-induced chirality in polymers.
- Analysis of photochromophore behavior within polymeric matrices (side-chain and main-chain).
- Discussion of superstructural and individual chromophore chirality origins.
Main Results:
- CPL induces chirality in polymers containing photochromophores, specifically azobenzene derivatives.
- In side-chain polymers, chirality arises from the aggregation-induced helical superstructures.
- In main-chain polymers, chirality originates from the inherent chirality of the backbone chromophores.
Conclusions:
- CPL irradiation is a viable method for inducing macroscopic chirality in photochromic polymers.
- The mechanism of chirality induction depends on the polymer architecture (side-chain vs. main-chain).
- These CPL-responsive chiral polymers show promise for optical-switching, optical-storage, and light-driven devices.
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