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Enhancing the Piezoelectric Properties of 3D Printed PVDF Using Concurrent Torsional Shear Strain
Pu Han1, Alireza Tofangchi2, Derek Carr2
1Ira A Fulton Schools of Engineering, Arizona State University, Tempe, AZ 85212, USA.
Polymers
|November 14, 2023
Summary
This study enhanced polyvinylidene difluoride (PVDF) piezoelectric properties by 400% using 3D printing with added torsional shear strains. This method controls polymer chain alignment and crystallinity for improved material performance.
Area of Science:
- Materials Science
- Polymer Science
- Additive Manufacturing
Background:
- Extrusion-based 3D printing introduces shear strains in polymers, affecting their properties.
- Polyvinylidene difluoride (PVDF) exhibits enhanced crystallinity and piezoelectricity when subjected to shear-induced polymer chain stretching.
Purpose of the Study:
- To investigate the impact of additional torsional shear strains during 3D printing on PVDF's piezoelectric properties.
- To explore the correlation between shear strain, crystalline phase formation, and piezoelectric enhancement in 3D printed PVDF.
Main Methods:
- Utilized extrusion-based 3D printing with a rotating nozzle to impart continuous torsional shear strains.
- Characterized the formation of crystalline β-phases using Fourier-transform infrared spectroscopy (FTIR).
- Quantified the enhancement in piezoelectric properties.
Main Results:
- Achieved a 400% enhancement in the piezoelectric property of 3D printed PVDF.
- Demonstrated that continuous torsional shear strains promote the formation of crystalline β-phases.
- Established a direct relationship between nozzle rotational speed and the extent of β-phase formation.
Conclusions:
- In-process shear strain is a viable method to control polymer chain alignment and crystalline phase in 3D printed materials.
- This approach offers a new pathway for developing advanced 3D printed polymers and composites with tailored piezoelectric properties.
- The study highlights the potential of additive manufacturing to engineer material properties through controlled mechanical stimuli.
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