Soft, tough, and fast polyacrylate dielectric elastomer for non-magnetic motor

Dielectric elastomer actuators (DEAs) with large electrically-actuated strain can build light-weight and flexible non-magnetic motors. However, dielectric elastomers commonly used in the field of soft actuation suffer from high stiffness, low strength, and high driving field, severely limiting the DEA's actuating performance. Here we design a new polyacrylate dielectric elastomer with optimized crosslinking network by rationally employing the difunctional macromolecular crosslinking agent. The proposed elastomer simultaneously possesses desirable modulus (similar to 0.073MPa), high toughness (elongation similar to 2400%), low mechanical loss (tan delta(m)=0.21@1Hz, 20 degrees C), and satisfactory dielectric properties (epsilon(r)=5.75, tan delta(e)=0.0019 @1kHz), and accordingly, large actuation strain (118% @ 70 MV m(-1)), high energy density (0.24 MJ m(-3) @ 70 MV m(-1)), and rapid response (bandwidth above 100Hz). Compared with VHB (TM) 4910, the non-magnetic motor made of our elastomer presents 15 times higher rotation speed. These findings offer a strategy to fabricate high-performance dielectric elastomers for soft actuators.

Automated summary

A new polyacrylate dielectric elastomer with an optimized crosslinking network has been designed, showing desirable mechanical and dielectric properties for large actuation strain and high energy density. Compared to conventional materials, it significantly improves the performance of non-magnetic motors.