Biomimetic polypyrrole based all three-in-one triple layer sensing actuators exchanging cations

Simultaneous actuation and sensing properties of a triple layer actuator interchanging cations are presented for the first time. Thick polypyrrole (pPy)/dodecylbenzenesulfonate (DBS) films (36 μm) were electrogenerated on stainless steel electrodes. Sensing characteristics of pPy-DBS/tape/pPy-DBS triple layer artificial muscle were studied as a function of electrolyte concentration, temperature and driving current using lithium perchlorate (LiClO4) aqueous solution as electrolyte. The chronopotentiometric responses were studied by applying consecutive square waves of currents to produce angular movements of ±45° by the free end of the triple layer. The evolution of the muscle potential (anode film versus cathode film) during current flow is a function of the studied chemical and physical variables. The electrical energy consumed to describe a constant angle is a linear function of the working temperature or of the driving electrical current, and a double logarithmic function of the electrolyte concentration. Those are the sensing functions. The cation exchanging bending triple layer actuator senses the working conditions. Similar sensing functions were described in the literature for devices interchanging anions. Irrespective of the reaction mechanism, a single electrochemo–mechanical device comprised of two reactive polymer electrodes (oxidation film and reduction film) works simultaneously as both sensor and actuator (self-sensing actuators). These are the general sensing properties of dense and biomimetic reactive gels of conducting polymers. Thus, any reactive device based on the same type of materials and reactions (batteries, smart windows, actuators, electron–ion transducers) is expected to sense surrounding conditions, as biological organs do.

[1]  Elisabeth Smela,et al.  The effect of pH on polymerization and volume change in PPy(DBS) , 1998 .

[2]  T. F. Otero,et al.  Bilayer dimensions and movement in artificial muscles , 1997 .

[3]  Laura Valero Conzuelo,et al.  Sensing and Tactile Artificial Muscles from Reactive Materials , 2010, Sensors.

[4]  Toribio F. Otero,et al.  Electrochemomechanical properties from a bilayer: polypyrrole / non-conducting and flexible material — artificial muscle , 1992 .

[5]  T F Otero,et al.  Artificial muscle: movement and position control. , 2004, Chemical communications.

[6]  Jianwei Xu,et al.  Blends of polyimide and dodecylbenzene sulfonic acid-doped polyaniline: Effects of polyimide structure on electrical conductivity and its thermal degradation , 2006 .

[7]  Toribio F. Otero,et al.  Soft, wet, and reactive polymers. Sensing artificial muscles and conformational energy , 2009 .

[8]  T. F. Otero,et al.  Artificial muscles based on conducting polymers , 1995 .

[9]  T. F. Otero,et al.  A sensing muscle , 2003 .

[10]  V. Koncar,et al.  Electro‐conductive sensors and heating elements based on conductive polymer composites , 2009 .

[11]  Luigi Fortuna,et al.  All-Organic Motion Sensors: Electromechanical Modeling , 2009, IEEE Transactions on Instrumentation and Measurement.

[12]  María Teresa Cortés,et al.  Linear movements from two bending triple-layers , 2007 .

[13]  T. F. Otero,et al.  Characterization of the movement of polypyrrole–dodecylbenzenesulfonate–perchlorate/tape artificial muscles. Faradaic control of reactive artificial molecular motors and muscles , 2011 .

[14]  H. Schneider,et al.  Chemomechanical Polymers as Sensors and Actuators for Biological and Medicinal Applications , 2007, Sensors.

[15]  Brian E. Conway,et al.  Modern Aspects of Electrochemistry , 1974 .

[16]  Abbas Z. Kouzani,et al.  Electrochemical fabrication and modelling of mechanical behavior of a tri-layer polymer actuator , 2011 .

[17]  E. Smela.  Conjugated Polymer Actuators for Biomedical Applications , 2003 .

[18]  T. Otero.  Electro-Chemo-Mechanical Actuators Touching and Sensing Both, Physical and Chemical Ambient , 2008 .

[19]  Hidenori Okuzaki,et al.  Electromechanical Properties of a Humido-Sensitive Conducting Polymer Film , 2000 .

[20]  Tae June Kang,et al.  Multifunctional nanocomposite membrane for chemomechanical transducer , 2010 .

[21]  W. R. Salaneck,et al.  Intrinsically conducting polymers : an emerging technology , 1993 .

[22]  María Teresa Cortés,et al.  Artificial Muscles with Tactile Sensitivity , 2003 .

[23]  T. F. Otero,et al.  Polypyrrole free-standing electrodes sense temperature or current during reaction , 2010 .

[24]  T. Otero,et al.  Polypyrrole artificial muscles: a new rhombic element. Construction and␣electrochemomechanical characterization , 2006 .

[25]  Gursel Alici,et al.  Electromechanical coupling in polypyrrole sensors and actuators , 2010 .

[26]  Chemomechanics with molecular force probes , 2010 .

[27]  T F Otero,et al.  Soft and wet conducting polymers for artificial muscles. , 1998, Advanced materials.