Intelligent materials structures

The chemical properties of the CEP structure determine the ability to recognize particular stimuli and respond to them appropriately. In addition, these properties determine how the conducting polymer interacts with other materials in the construction of composite intelligent material structures. Most polymers are capable of, and indeed do, interact with other molecules. Such molecules may be part of larger molecular structures (important in the area of compatible materials), or they may be solvent molecules (such interaction can influence many processes including dissolution) or specific molecules in a solvent or gaseous medium. 

With these systems, conducting polymers start to grow from the electrode side. If polymerization times are short, only the electrode side is conductive, enabling a degree of spatial control that allows structures to be formed. As pointed out earlier, this may be important in producing intelligent material structures where localized polymerization is required to provide spatial distribution of function. 

This ability to pattern in three or two dimensions is critical to the development of intelligent material structures containing conducting electroactive polymers. Advances in patterning are described in the following section. 

Conducting polymers have been demonstrated to be usable as dynamic, intelligent membrane systems. The unique electrochemical properties enable extern stimuli to be used to turn transport on and off, to tune the selectivity and the rate of transport. This technology is now being developed for numerous applications and as the basis of Intelligent Material Structures. 

The chemical properties of the resultant structure determine the ability to recognize particular stimuli and respond to them appropriately. In addition, these properties determine how the conducting polymer interacts with other materials in the construction of composite intelligent material structures. 

Qing, X. P. Chan, H.-L. Beard, S. I Kumar, A. 2006. An active diagnostic system for structural health monitoring of rocket engines. /. Intelligent Material Systems and Struct. 17 619-628. 

Okuzaki H, Osada Y (1993) Journal of Intelligent Material Systems and Structures 4 50... 

From this perspective, temperature-responsive hydrogels are reviewed as agents in the design of effective polymeric structures for thermo-responsiveness as Intelligent Materials . 

The definition of a sensor is that it reacts to a parameter (for example, the volume of the mercury pool in a thermometer increases with temperature), and the intensity of the reaction is in relation to the parameter - for example, the measurement of an electrical current that is in relation to the concentration of the analyte oxidised or reduced at the electrode surface. The parameter to be investigated is the concentration of the analyte, while the parameter measured is an electrical current. As for the real devices, ultimately most signals are being transformed into electric ones. Electroactive materials are consequently of utmost importance with respect to intelligent textiles. Of course, apart from technical considerations, concepts, materials, structures and treatments must focus on the appropriateness for use in or... 

The discovery of inherently conducting polymers also provided a class of materials that would feed the imagination of Scientists and Engineers in pursuit of Intelligent Material Systems and Structures. No other class of materials possess the inherent properties necessary to function as sensors, information processors and actuators, as well as the possibility of providing an energy conversion system. 

There is no doubt that as we develop an understanding of how best to assemble and integrate inherently conducting polymers with other structures, while retaining their functionality, then real intelligent material systems will emerge in the new millennium. 

Conducting electroactive polymers (CEPs) such as polypyrrole, poly thiophene, polyaniline, and sulfonated polyaniline (1-4 shown subsequently) are complex, dynamic structures that captivate the imagination of those of us involved in intelligent material research.1 2 3 4 5... 

The diversity of approaches used to develop intelligent material systems and structures is a healthy symptom of the stage of development of this scientific endeavor. 

To function as intelligent materials, conducting polymers must be capable of stimuli recognition, information processing, and response actuation. As a result, they must possess appropriate chemical properties that change in response to stimuli and appropriate electrical properties that allow information to be transported within the structure and switches to be actuated. The mechanical properties must also be considered, because the creation of materials with ideal chemical and electrical properties, but with inappropriate mechanical properties, will be of questionable value. 

Rapid advances in synthetic polymer science and nanotechnology have now placed us in a position to utilize the unique properties of this versatile class of materials. Our ability to design and assemble polymers from the molecular level, coupled with a better understanding of structure-property relationships enables the design of sophisticated structures. We believe that inherently conducting electroactive polymers (CEPs) will continue to play a central role in the development of intelligent material science over the following decades. 

Fig. 1.6. Scheme of smart material structure. (1) adaptive structure, (2) controlled, (3) active, (4) intelligent structure... 

Tobushi, H., Hashimoto, T., Ito, N., Hayashi, S., Yamada, E., 01/1998. Shape fixity and shape recovery in a film of shape memory polymer of polyurethane series. Journal of Intelligent Material Systems and Structures 9 (2), 127—136. http //dx.doi.org/10.1177/... 

Seim, B., et al., 2010. Polymeric optical fiber fabrics for illumination and sensorial applications in textiles. Journal of Intelligent Material Systems and Structures 21 (11), 1061—1071. Available at http //jim.sagepub.eom/cgi/doi/10.1177/1045389X10377676 (accessed 22.09.14.). 

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