Conductive polymers ferroelectric

Key Words Dipolar glasses, Ferroelectric relaxors, Conducting polymers, NMR line shape, Disorder, Local polarization related to the line shape, Symmetric/asymmetric quadrupole-perturbed NMR, H-bonded systems, Spin-lattice relaxation, Edwards-Anderson order parameter, Dimensionality of conduction, Proton, Deuteron tunnelling. 

Conducting polymers also can be utilized to form core-shell structures with high dielectric constant particles. Fang et al. used PANl to encapsulate barium titanate via in situ oxidative polymerization. They examined the influence of the fraction of BaTiOs particles on the ER behavior, and found that the PANl/ BaTiOs compo-sites-based ERFs exhibit a better ER effect than does pure PANl, which result might be due to the unique ferroelectric properties as well as the high dielectric constant of BaTiOs nanoparticles. 

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. 

Studies in the areas of conductive polymers and ferroelectric materials constitute a relatively small subset of porphyrin materials research. Nonetheless, the versatility of porphyrins has allowed for some interesting and useful results in these areas. We will examine the variety of approaches toward the creation of porphyrin-based conductive polymers and the potential applicability of porphyrinic polymers as ferroelectric materials. 

The above data show that mixing a polymer with a plasticizer has only marginal influence on volume resistivity of material. But still plasticizers are used in many applications of polymers in conductive and ferroelectric applications. ... 

Considering the existence of volume changes, Baughman et al. suggested the possibility for using conducting polymers as basic materials for the construction of actuators, similar to those developed from piezoelectric, electrostrictive, or ferroelectric inorganic actuators [53,54]. 

The present 10 volume handbook has a much broader scope. It includes semiconductor materials, quantum wells and quantum dots, liquid crystals, conducting polymers, laser materids, photoconductors, electroluminescent and photorefractive materials, nanostructured, supramolecular, and self-assembled materials, ferroelectrics, and superconductors. Applications of these materials in photoconductors, optical fibers, xerography, solar cells, dynamic random access memory, and sensors are described. The Handbook contains contributions by 180 leading experts from 25 different countries. It truly represents the worldwide research efforts and results that support the global market of optoelectronics. All scientific and technical workers in this broad field are indebted to the contributing authors, the editor and Academic Press for publishing this comprehensive handbook for the new millennium. It will support further growth in a field that already has surpassed my wildest expectations of 40 years ago. 

High Tc Superconductors and Organic Conductors Ferroelectrics and Dielectrics Chalcogenide Glasses and Sol-Gel Materials Nanostructured Materials Liquid Crystals, Display, and Laser Materials Conducting Polymers Nonlinear Optical Materials... 

Most of the inorganic and polymeric actuators present in current technological world are based on volume variations produced by electric fields. Engineers and physicists are familiar wifli fliose physical and mafliematical models developed during the past century to describe piezoelectric, electrostrictive, ferroelectric, coulombic, or electroosmotic actuators. Some of those models have been translated to try to describe actuators based on conducting polymers, driven by charge, not by fields. 

Composites. See also Composite materials Composites. See also Laminates aluminum-filled, 10 15-28 carbon fiber, 26 745 ceramic-filled polymer, 10 15-16 ceramic-matrix, 5 551-581 conducting, 7 524 from cotton, 8 31 ferroelectric ceramic-polymer,... 

Chemically deposited non stoichiometric cuprous sulfide films (Cui.gS) have been used as conducting layers as reported by Grozdanov et al. [50]. The films, deposited at 40 °C, present a resistivity of 2.10 Q.cm. In addition they present optical transmission values between 50 and 70% in the visible range for a 0.12 pm thick film. These properties have been used for ohmic contacts to ferroelectric films and transparent conducting coatings on polymers. These films can also be used as chemical sensors for Cu + ions. Note that due to the low deposition temperature polymer substrates can be used [61]. 

C.-C. Wang, J.-F. Song, H.-M. Bao, Q.-D. Shen, and C.-Z. Yang, Enhancement of electrical properties of ferroelectric polymers by polyaniline nanofibers with controllable conductivities, Adv. Funct. Mater., 18, 1299-1306 (2008). 

Conduction and dielectric properties are not the only electrical properties that polymers can exhibit. Some polymers, in common with certain other types of materials, can exhibit ferroelectric properties, i.e. they can acquire a permanent electric dipole, or photoconductive properties, i.e. exposure to light can cause them to become conductors. Ferroelectric materials also have piezoelectric properties, i.e. there is an interaction between their states of stress or strain and the electric field across them. All of these properties have potential applications but they are not considered further in this book. 

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