Composite materials polymer-metal composites

There has been extensive recent use of track-etched membranes as templates. As will be discussed in detail below, these membranes are ideal for producing parallel arrays of metal nanowires or nanotubules. This is usually done via electroless metal deposition [25], but many metals have also been deposited electrochemically [26]. For example, several groups have used track-etched templates for deposition of nanowires and segmented nanowires, which they then examined for giant magnetoresistance [27-29]. Other materials templated in the pores of track etch membranes include conducting polymers [30] and polymer-metal composites [31]. 

EAPs can be broadly divided into two categories based on their method of actuation ionic and field-activated. Further subdivision based on their actuation mechanism and the type of material involved is also possible. Ionic polymer-metal composites, ionic gels, carbon nanotubes, and conductive polymers fall under the ionic classification. Ferroelectric polymers, polymer electrets, electrostrictive polymers, and dielectric elastomers fall under the electronic classification. 

Shahinpoor and Moj aired used ion-exchange materials and membranes to produce electrically responsive actuators [41—48] and also encapsulated ion-exchange membrane sensor/actuators. Shahinpoor used electrically responsive polymers coupled with springs and other mechanical devices to improve upon electrically responsive actuators [52] and ionic polymeric conductor composites and ionic polymer metal composites to drive pumps and mini-pumps [41]. 

Shahinpoor M, Kim KJ (2004) Ionic polymer-metal composites III. Modeling and simulation as biomimetic sensors, actuators, transducers and artificial muscles (review paper). Smart materials and stractures. Int J 13(6) 1362-1388. doi 10.1088/0964.1726/13/6/009... 

In other words, because the viscosity of the mixture is usually lower during processing, the denser metallic particles may tend to separate. Given the large number of variables in preparing a composite, these materials may suffer from unpredictable and uncontrollable heterogenieties and from lack of reproducibility due to the preparative "art" involving formulation of both the metal powder dispersion and the polymer-metal composite. 

A common configuration involves sandwiching the polymer between two sheets of metal to make a true composite material. While such composites exhibit optimum damping characteristics, they necessarily have limited form-ability. Alternatively, damping tapes (Wollek, 1965) have found important applications. In these systems, the adhesive serves also as the damping layer, and aluminum foil as the backing multiple layers may be applied with good effect. 

TABLE 16.2 Comparison between Two Mechanical Properties of Different Actuating Materials Skeletal Muscles, Thermomechanical (Thermal Liquid Crystals and Thermal Shape Memory Alloys), Electrochemomechanical (Conducting Polymers and Carbon Nanotubes) and Electromechanical (Ionic Polymer Metal Composites, Field Driven Liquid Crystal Elastomers, Dielectric Elastomers)... 

The purpose of this book is to provide a focused, in-depth, yet self-contained treatment of recent advances made in several most promising EAP materials. In particular, the book covers two classes of ionic EAPs, ionic polymer-metal composites (IPMCs) and conjugated polymers, and one class of electronic EAP materials, dielectric elastomers. Ionic EAPs realize actuation through ion transport, and thus require very low voltages (a few volts) to operate, but their bandwidths are typically lower than tens of Hz. On the other hand, dielectric elastomers rely on electrostatic forces to operate and thus require high actuation voltages (kilovolts), but... 

Throughout the chapters of this book we considered several types of electroactive materials in a view of using them as biomimetic artificial muscles. In particular, ionic polymer-metal composites, conjugated polymers, and dielectric elastomers were considered. 

Abdelnour, K., Mancia, E., Peterson, S. D. and Porfiri, M. (2009). Hydrodynamics of underwater propulsors based on ionic polymer metal composites A numerical study, Smart Materials and Structures 18, 8, pp. 085006 1-11. 

Bonomo, C., Fortrma, L., Giaimone, R, Graziani, S. and Strazzeri, S. (2006). A model for ionic polymer metal composites as sensors. Smart Materials and Structures 15, pp. 749-758. 

Chen, Z., Hedgepeth, D. R. and Tan, X. (2009). A nonlinear, control-oriented model for ionic polymer-metal composite actuators. Smart Materials and Structures 18, pp. 055008 1-9. 

Costa Branco, P. J. and Dente, J. A. (2006). Derivation of a continuum model and its electric equivalent-circuit representation for ionic polymer-metal composite (IPMC) electromechanics. Smart Materials and Structures 15, pp. 378-392. 

Del Bufalo, G., Placidi, L. and Porfiri, M. (2008). A mixture theory framework for modeling the mechanical actuation of ionic polymer metal composites. Smart Materials and Structures 17, pp. 045010 1-14. 

Keshavarzi, A., Shahinpoor, M., Kim, K. J. and Lantz, J. W. (1999). Blood pressure, pulse rate, and rhythm measurement using ionic polymer-metal composite sensors, in J. Bar-Cohen (ed.). Smart Structures and Materials 1999 Electroactive Polymer Actuators and Devices, Vol. 3669 (SPIE, Bellingham, WA), pp. 369-376. 

Kim, B., Kim, D., Jung, J. and Park, J. (2005). A biomimetic undulatory tadpole robot using ionic polymer-metal composite actuators. Smart Materials and Structures 14, pp. 1579-1585. 

Paquette, J. W., Kim, K. J., Nam, J.-D. and Tak, Y. S. (2003). An Equivalent Circuit Model for Ionic Polymer-Metal Composites and their Performance Improvement by a Clay-Based Polymer Nano-Composite Technique, Journal of Intelligent Material Systems and Structures 14, 10, pp. 633-642. 

Shahinpoor, M., Bar-Cohen, Y., Simpson, J. O. and Smith, J. (1998). Ionic polymer-metal composites (ipmcs) as biomimetic sensors, actuators and artificial muscles - a review. Smart Materials and Structures 7, 6, p. R15. 

Shahinpoor, M. and Kim, K. (2002). Mass transfer induced hydraulic actuation in ionic polymer-metal composites. Journal of Intelligent Material Systems and Structures 13, pp. 369-376. 

Shahinpoor, M. and Kim, K. J. (2000). The effect of surface-electrode resistance on the performance of ionic polymer-metal composite (IPMC) artificial muscles, Smart Materials and Structures 9, pp. 543-551. 

Within the frames of this chapter, polymer materials and polymer-metallic composites (PSU/Ag) were obtained and examined. On the basis of the performed tests, it was stated that the polymer composites with a poly-sulfone matrix modified with nano-silver have a bactericidal function in contact with Gram-positive (S. aureus) and Gram-negative E. coli) bacteria. The highest antibacterial efficacy was recorded for the composites... 

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