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A Ribbon Model for Nematic Polymer Networks
Harmeet Singh1, Epifanio G Virga2
1Laboratory for Computation and Visualization in Mathematics and Mechanics, Institute of Mathematics, École Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland.
Journal of Elasticity
|June 9, 2023
Summary
We developed a theory for nematic polymer network (NPN) ribbons, predicting serpentine deformations in response to heat or light. This work simplifies complex material behavior for ribbon applications.
Area of Science:
- Materials Science
- Polymer Physics
- Soft Matter Physics
Background:
- Nematic polymer networks (NPNs) combine rubber elasticity with liquid crystal properties.
- NPNs respond to external stimuli like heat and light.
- Existing models describe NPN sheets but not ribbons.
Purpose of the Study:
- To derive a theoretical model for the deformation of NPN ribbons.
- To simplify a 2D sheet energy model to a ribbon energy model.
- To demonstrate ribbon behavior with a specific example.
Main Methods:
- Utilized a dimension reduction method.
- Derived ribbon energy from a pre-existing 2D sheet energy model.
- Applied boundary conditions to a rectangular NPN ribbon model.
Main Results:
- Developed a theoretical framework for NPN ribbon deformation.
- Successfully predicted in-plane serpentine deformations in a model ribbon.
- The derived energy model is suitable for NPN ribbons.
Conclusions:
- The dimension reduction approach effectively models NPN ribbon mechanics.
- NPN ribbons can exhibit complex, stimulus-responsive deformations.
- This theory provides a basis for designing novel NPN ribbon-based devices.
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