Electrically responsive multilayer soft actuators using a solvent-free high dielectric permittivity polysiloxane ink.

Area of Science:

• Materials Science
• Polymer Science
• Actuator Technology

Background:

• Multilayer soft dielectric elastomer actuators (DEAs) are crucial for converting electrical energy into mechanical work.
• Enhancing DEA performance requires materials with higher dielectric permittivity and efficient manufacturing processes.
• Current large-scale DEA production is limited to polydimethylsiloxane (PDMS) with low dielectric permittivity.

Purpose of the Study:

• To develop a novel, processable, high-dielectric-permittivity elastomer ink for scalable DEA fabrication.
• To overcome the limitations of integrating high-permittivity materials into multilayer DEA devices.
• To demonstrate the potential for industrial-scale manufacturing of advanced DEAs.

Main Methods:

• A solvent-free, high-dielectric-permittivity capillary ink with a long pot life and rapid thermal crosslinking was synthesized.
• The ink was processed into ultrathin films on preheated metal substrates.
• Characterization of the elastomer's dielectric properties, mechanical properties, and actuator performance was conducted.

Main Results:

• The developed elastomer exhibits a dielectric permittivity of 11, a storage modulus of 350 kPa, and negligible mechanical losses.
• Single-layer DEAs achieved 5.7% lateral strain at 26.2 V µm⁻¹ and stable actuation over 5000 cycles.
• Stripe actuators demonstrated 5.5% lateral strain at 19.0 V µm⁻¹ and 1 Hz, increasing to 9% at 5 Hz.

Conclusions:

• The new ink enables scalable, solvent-free fabrication of high-performance multilayer DEAs.
• The developed material significantly advances the industrial applicability of high-dielectric-permittivity polysiloxanes.
• This work represents a major step towards commercializing advanced DEA technologies.