Mechanisms of large actuation strain in dielectric elastomers

• Published in: Journal of polymer science. Part B, Polymer physics Vol. 49; no. 7; pp. 504 - 515
• Main Authors: Koh, Soo Jin Adrian, Li, Tiefeng, Zhou, Jinxiong, Zhao, Xuanhe, Hong, Wei, Zhu, Jian, Suo, Zhigang
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc., A Wiley Company 01.04.2011; Wiley; Wiley Subscription Services, Inc
• Subjects: Actuation; Applied sciences; Deformation mechanisms; dielectric properties; Dielectrics; Elastomers; Electric potential; Exact sciences and technology; high performance polymers; Mechanical properties; Organic polymers; Physicochemistry of polymers; physics; polymers; prediction; Properties and characterization; Reproduction; stimuli-sensitive polymers; Strain; tension; theory; thermodynamics; Voltage; strain; stimuli-sensitive polymers; High strain; tension; Dielectric materials; Elastomer; dielectric properties; Theoretical study; thermodynamics; Electromechanical effects; Modeling; Mechanism; elastomers; high performance polymers; Electric field effect; theory; Actuator
• ISSN: 0887-6266; 1099-0488; 1099-0488
• DOI: 10.1002/polb.22223

Subject to a voltage, a dielectric elastomer (DE) deforms. Voltage-induced strains of above 100% have been observed when DEs are prestretched, and for DEs of certain network structures. Understanding mechanisms of large actuation strains is an active area of research. We propose that the voltage-stretch response of DEs may be modified by prestretch, or by using polymers with “short” chains. This modification results in suppression or elimination of electromechanical instability, leading to large actuation strains. We propose a method to select and design a DE, such that the actuation strain is maximized. The theoretical predictions agree well with existing experimental data. The theory may contribute to the development of DEs with exceptional performance.