Artificial muscles based on Polyacrylonitrile based polymer electrolyte

A system capable of converting chemical energy into mechanical energy can be treated as an artificial muscle or an actuator. Direct drive actuators incorporating materials like ferroelectric ceramics and piezoelectric polymers suffer from various limiting factors. It has been realized that polymers can be used to fabricate such muscles with appreciable performances. Movement of the muscles takes place as a result of incorporation and ejection of ions. In this study, the fabrication of a dry muscle using a Polyacrylonitrile (PAN) based electrolyte and two polypyrrole (PPy) electrodes and investigation of its performance is discussed.

The composition of the polymer electrolyte was 21mol%PAN : 39mol%EC : 33mol%PC : 7mol%LiCF₃SO₃) and it has a good mechanical stability. Two identical polypyrrole electrodes have been polymerized in the presence of dodecylbenzenesulfonate (DBS). An assembly of PPy : polymer electrolyte : PPy was formed in the normal atmosphere. Movements were observed using cyclic voltametry technique. Simultaneously, horizontal displacement of the muscle was observed. A rough estimation was done about the velocity of the muscles during oxidation and reduction. During reduction, a faster movement was obtained.  

doi:10.4038/sljp.v8i0.212  

Sri Lankan Journal of Physics, Vol. 8 (2007) 39-45