Electro-elastocapillary Rayleigh-plateau instability in dielectric elastomer films.

Area of Science:

• Soft Matter Physics
• Materials Science
• Continuum Mechanics

Background:

• Dielectric elastomers (DEs) are smart materials with tunable mechanical properties.
• Rayleigh-Plateau instability typically describes fluid jet breakup due to surface tension.
• Understanding instability modes in soft solids is crucial for device design.

Purpose of the Study:

• To investigate the emergence of electro-elastocapillary Rayleigh-plateau instability in dielectric elastomer films.
• To analyze the influence of electric fields on instability phenomena in DEs.
• To differentiate between buckling and Rayleigh-plateau instabilities in DEs under varying conditions.

Main Methods:

• Finite element simulations were employed to model DE behavior.
• Linear stability analysis was performed to determine critical conditions for instability.
• 2D plane strain conditions were used to simplify the analysis.

Main Results:

• An electro-elastocapillary Rayleigh-plateau instability was observed in DE films under electric fields.
• Buckling instability occurs at low elastocapillary numbers, while Rayleigh-plateau instability dominates at higher numbers.
• Electric fields are essential for inducing this instability in DEs, unlike in simple fluid systems.

Conclusions:

• The study reveals a novel instability mechanism in dielectric elastomers driven by electro-elastocapillary forces.
• Geometry, boundary conditions, and multi-physical couplings significantly influence instability modes in soft solids.
• This work provides new insights into the mechanics of soft materials and their response to electric fields.