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Published on: September 20, 2017
Light-induced deformation of azobenzene elastomers: a regular cubic network model
V Toshchevikov1, M Saphiannikova, G Heinrich
1Leibniz Institute of Polymer Research Dresden, 01069 Dresden, Germany. toshchevikov@ipfdd.de
The Journal of Physical Chemistry. B
|December 22, 2011
Summary
We developed a theory explaining how light deforms azobenzene elastomers. Material structure dictates expansion or contraction, with cross-linking affecting deformation magnitude.
Area of Science:
- Polymer Science
- Materials Science
- Photomechanics
Background:
- Azobenzene elastomers exhibit light-induced deformation due to photosensitive azo-moieties.
- The orientation approach explains mechanical stress from chromophore reorientation relative to light's electric vector.
Purpose of the Study:
- To propose a microscopic theory for light-induced deformation in azobenzene elastomers.
- To investigate the influence of chemical structure and cross-linking on photomechanical behavior.
Main Methods:
- Utilized a microscopic theory based on the orientation approach.
- Employed a regular cubic network model of freely jointed polymer chains with azobenzene chromophores.
- Calculated deformation under homogeneous light illumination.
Main Results:
- Photomechanical behavior is highly sensitive to the elastomer's chemical structure, specifically chromophore orientation distribution.
- Azobenzene elastomers can expand or contract along the light's electric vector based on their chemical makeup.
- Increased cross-linking density reduces the magnitude of light-induced deformation.
Conclusions:
- The chemical structure of spacers critically determines the direction and magnitude of light-induced deformation.
- Cross-linking degree inversely correlates with deformation magnitude.
- Inhomogeneous light can induce bending motions in azobenzene elastomers.
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