Artificial Muscles: Dielectric Elastomers Responsive to Low Voltages.

Area of Science:

• Materials Science
• Polymer Chemistry
• Actuator Technology

Background:

• Dielectric elastomer actuators (DEA) technology faces industrialization challenges due to the lack of soft, high-permittivity elastomers responsive to low voltages.
• Existing materials often compromise on elasticity, insulating properties, or processability in thin films.

Purpose of the Study:

• To develop novel elastomers with high dielectric permittivity (εr ≈ 18) suitable for low-voltage DEA applications.
• To achieve tunable elastic modulus and excellent mechanical and electrical properties for advanced actuator performance.
• To demonstrate the processability of these elastomers into thin films using conventional techniques.

Main Methods:

• Synthesis of novel elastomer materials with tailored dielectric and mechanical properties.
• Characterization of elastic modulus, dielectric permittivity, and electrical breakdown strength.
• Fabrication and testing of thin-film elastomers for actuation performance and long-term stability.
• Evaluation of processability using conventional thin-film deposition techniques.

Main Results:

• Developed soft elastomers with εr = 18, storage modulus E = 350 kPa, tanδ = 0.007, achieving 13% lateral strain at 13 V µm⁻¹.
• Demonstrated stable actuation over 50,000 cycles at 10 Hz.
• Created stiffer elastomers (E = 790 kPa, tanδ = 0.0018) with breakdown fields nearing 100 V µm⁻¹, the highest reported for high-permittivity elastomers.
• Achieved actuator operation at voltages as low as 200 V.

Conclusions:

• The developed elastomers overcome key limitations in DEA technology, offering high performance at low voltages.
• Tunable properties, excellent processability, and high breakdown fields position these materials for significant advancements in DEA industrialization.
• The use of inexpensive, readily available materials and scalable synthesis methods ensures the potential for widespread adoption and commercialization.