Permethylpolyazine-ethylene propylene diene elastomer (EPDM) as an electroactive actuator

Abstract

Elastomers that can respond to external stimuli, such as temperature and electric field, are known as dielectric elastomers, consisting of either a polar molecule or an unsaturated structure on the side chain with induced dipole moments. In our work, we prepared the electroactive polymers from blends of dielectric elastomers and a conductive polymer. For the dielectric elastomers, ethylene propylene diene elastomer (EPDM NORDEL IP 5565) was used as the matrix phase. The conductive polymers, permethylpolyazine (PAZ), were synthesized and doped with iodine at various doping levels for improving the electrical conductivity. The blends were prepared by the mechanical blending of highly doped PAZ particles with EPDM at various particle concentrations from 5 vol% to 20 vol%. The chemical structures of undoped and doped PAZ were characterized by FT-IR. The electromechanical properties were studied under an oscillatory shear mode in the frequency range 0.1-100 rad/s with electric field strength varying from 0 to 1 kV/mm at 27℃. The effects of particle concentration on storage modulus response, G', storage modulus sensitivity, G'/G'0, and electrical conductivity, σ, and dielectric constant, ɛ' at 27℃ and 100 rad/s were also studied. G' and G'/G'0 increase with increasing electric field strength, and particle concentration. The electrical conductivity and dielectric constant increase with particle concentration.