Insights into multi-scale structural evolution and dielectric response of poly(methyl acrylate) under pre-strain: A...

Area of Science:

• Materials Science
• Polymer Physics
• Dielectric Materials

Background:

• Dielectric elastomers are crucial for soft robotics and actuators.
• Understanding pre-strain effects is vital for optimizing their performance.
• Multi-scale responses in polymers under strain are complex and challenging to model.

Purpose of the Study:

• To investigate the multi-scale structural evolution of dielectric elastomers under pre-strain.
• To elucidate the relationship between pre-strain, dielectric constant, and polymer chain dynamics.
• To identify mechanisms for enhancing dielectric properties through controlled pre-strain.

Main Methods:

• Computational simulations were used to analyze poly(methyl acrylate) under varying pre-strain.
• Electronic structure, molecular chain conformation, and aggregation structure were examined.
• Charge distribution, electrostatic potential, HOMO-LUMO bandgap, and segment dynamics were analyzed.

Main Results:

• The dielectric constant of poly(methyl acrylate) initially increases and then decreases with pre-strain above 200%.
• Optimized chain conformation enhances polarity domains and electron polarization.
• Permittivity transitions from isotropic to anisotropic behavior under strain.

Conclusions:

• Pre-strain significantly influences dielectric elastomer properties at multiple scales.
• Controlled molecular chain conformation and dynamics are key to tuning dielectric performance.
• This research offers insights into the intrinsic mechanisms governing pre-strain effects in polymers.