Effect Of Electric Field On Electro-Viscoelasticity Of TiO₂/Si R Composites Dielectric Elastomer

Dielectric elastomers can be controlled by electric fields to change its shape or volume,and have a wide range of application prospects in robotics and energy fields.The force-electric coupling of dielectric elastomers in the process of electric field induced deformation has been a research frontier and hotspot in this field.However,the dielectric elastomer is generally simplified as an ideal elastomer in the force-electrical model.Researchers pay less attention to the viscoelasticity which change under force-electrical coupling effect.In particular,there is a lack of in-depth study on the dynamic viscoelastic effects on dielectric elastomers caused by the electric field.In this dissertation,amorphous TiO₂ particles were used as dispersed phase particles and room temperature vulcanized silicone rubber as polymer matrix to prepare composite dielectric elastomers with different structures.This paper studied the effect of applied electric field on the deformation and viscoelasticity,and laid a foundation for force-electrical model of dielectric elastomers.The main research contents of this paper are as follows:?1?The TiO₂/silicone dielectric elastomers with particle mass fractions of 10%,20%and30%were tested by rheological tests.The results show that the viscoelastic change of dielectric elastomer is getting more and more obvious with the increase of applied electric field.In addition,the electric field sensitivity of dielectric elastomers is higher with the increase of particle content.Under the electric field of 5 kV/mm,the storage modulus of the dielectric elastomer with the particle content of 30%increased by 18.1%compared with the same sample without electric field.Under the action of applied electric field,the viscoelasticity of TiO₂/silicone rubber dielectric elastomer will change obviously,and the higher the content of dispersed phase particles,the more obvious the change.?2?The dynamic viscoelasticity of dielectric elasticity filled with random TiO₂ particles and oriented TiO₂ particles was tested by rheological test.The results show that the dielectric elastomer filled with oriented TiO₂ particles has higher electric field sensitivity.Under the electric field of 5 kV/mm,the storage modulus of the dielectric elastomer filled with oriented TiO₂ particles increased by 75.5%compared with the same sample without electric field.Under the electric field,the distribution pattern of dispersed phase particles can significantly affect the viscoelasticity of dielectric elastomers.