Polyurethane/polypyrrole

Conducting composite polymer materials have also been prepared from the dispersed phase of concentrated emulsions. Polyurethane/polypyrrole composites [165] were obtained by blending an aqueous suspension of polypyrrole with a HIPE of a chloroform solution of polyurethane in aqueous surfactant... 

Yanilmaz M., Kalaoglu F, Karakas H., and Sarac A. S., Preparation and characterization of electrospun polyurethane-polypyrrole nanofibers and films,/ Appl. Polym. Sci, 2012,125,4100-4108. 

Yoon el al. [112] reported an all-solid-state sensor for blood analysis. The sensor consists of a set of ion-selective membranes for the measurement of H+, K+, Na+, Ca2+, and Cl. The metal electrodes were patterned on a ceramic substrate and covered with a layer of solvent-processible polyurethane (PU) membrane. However, the pH measurement was reported to suffer severe unstable drift due to the permeation of water vapor and carbon dioxide through the membrane to the membrane-electrode interface. For conducting polymer-modified electrodes, the adhesion of conducting polymer to the membrane has been improved by introducing an adhesion layer. For example, polypyrrole (PPy) to membrane adhesion is improved by using an adhesion layer, such as Nafion [60] or a composite of PPy and Nafion [117],... 

This diol was mixed with other diols, then reacted with diisocyanates to form polyurethanes. The electrically conducting polymers, polyaniline and polypyrrole, prevent corrosion of steel.105 One of the best formulations uses polyaniline with zinc nitrate, which is then covered with an epoxy resin topcoat. Polyorganosiloxanes have been grafted to starch using the sol-gel method with alkoxysi-lanes. These materials have been complexed with cerium ions to provide corrosion protection for aircraft that is expected to be 50% cheaper than conventional coatings.106... 

Several types of monomers have been used for this (Fig. 6), especially easily polymerisable molecules. Acrylate monomers [46-51 ] and acrylamides have been used the most [52-56]. Systems with polystyrene [47, 57-63] and poly-siloxane [64] backbones have also been synthesised. Recently, other types of polymer such as polyurethanes [65],polypyrroles [66-68], and polyimidazoles [69,70] have been used in special applications. Renewed interest has also been shown in silicas and sol-gel glasses [71]. 

It was not until 1984 and 1985 that we succeeded in comminuting polypyrrol and polyaniline in the melt by means of ultrasound and dispersing them in special polymer blends. Only two years later we were able to report to the world conference on Organic Metals in Kyoto (Japan) that dispersed conductive polymers displayed a conductivity breakthrough at a concentration of less than ten percent by volume in a thermoplastic polymer matrix—for example a polyvinylchloride (PVC), polyester or polyurethane—and could be processed in the form of such blends. 

The use of PPy-Nafion-PPy trilayers has enabled a low-power pump to be constructed at Dublin in which two trilayers act as tweezers in compressing the fluid inside a flexible polyurethane tube. Through the choice of conical inlets and outlets to create unidirectional fluid movement, flow rates of up to 1.6 pi s were achieved [96]. A further pmnp design involving a polypyrrole-polydimethylsiloxane diaphragm with check valves has been developed, with a pumping rate of 52 pi min [97],... 

Li, M., Li, H., Zhong, W., Zhao, Q., Wang, D., 2014. Stretchable conductive polypyrrole/polyurethane (PPy/ PU) strain sensor with netlike microcracks for human breath detection. ACS Appl. Mater. Interfaces 6,... 

FIGURE 8.75 Scanning electron microscope (SEM) images of the surface of the polypyrrole films. These films were prepared by the electrochemical deposition for (a) 15, (b) 10, (c) 5, (d) 3, and (e) 1 min onto a drawn polyurethane sheet. The elongation ratio was 30%, and the drawing direction corresponded to the horizontal direction of these images. (From Masashi, W., and Toshihiro, H., /. Polym. Sd. Pol. Chem., 42, 2460, 2004. With permission.)... 

Fu, Y., et al. 1997. Synthesis of conductive polypyrrole/polyurethane foams via a supercritical fluid process. Macromolecules 30 7611. 

Aniline is used as a chemical intermediate to prepare isocyanates for making polyurethanes, antioxidants, and vulcanization accelerators, as well as in the manufacture of agricultural fungicides, herbicides and insecticides and in the preparation of certain dyes. Similarly, pyrrole is used as a chemical intermediate in the preparation of electrically conducting polypyrrole by means of an electrochemical polymerization process. Pyrrole has few other industrial uses. 

These techniques have been applied to PTFE [211,212], polybutadiene [213], rubbers [214, 215], acrylics [216,217], PE [218-220], polyurethane [221], PS [222], polyvinyl carbazole [223], polymalic acid [224], poly-P-hydroxybutyrate and poly-p-hydroxyvalerate [225], y-glycidoxy propyltrimethoxysilane [226], polypyrrole [227], and acrylonitrile-butadiene rubber [228]. 

A three-step procedure to obtain polypyrrole-based composites has been described, by blending a concentrated emulsion which contains polyurethane in chloro-... 

Many thermoplastic polymers have been used as matrix with nanocellulose as reinforcement such as poly(vinyl alcohol) (PVA) [130, 175], polyurethane [176, 177], polypyrrolle [178], polypropylene [179], poly(latic acid) (PLA) [180], hydroxypropyl-cellulose (HPC) [74], polyacrylamide [181], etc. Figures 11.24 [182] and 11.25 [178] are examples of thermoplastics reinforced by nanocellulose. 

Polyvinylidene fluoride PPy Polypyrrole P(VDF-TrFE) Poly(inylidene difluoride-trifluoroethylene) PANi Polyaniline PEO Poly(ethylene oxide) PU Polyurethane PBT Poly (butylene terephthalate) DMF N, iV-dimethylformamide THF Tetrahydrofuran TFA Trifluoro acetic acid FA Formic acid DCM Dichloromethane DMAc N, jV-dimethylacetamide HFIP Hexafluoro-2-propanol. 

Fig. 11 Configuration and assembly of the tube-in-tube actuation concept (TITAN). A a porous PVDF fiber to provide support for the metallized polyurethane tube (OD 1050 pm, ID 950 pm). B as a working electrode, a metallized polyurethane tube wrapped with 050 pm platinum wire coated with polypyrrole. C a PVDF membrane used for the electrolyte storage. D as the auxiliary electrode, a metallized PVDF membrane coated with polypyrrole connected via stainless steel mesh. E aplastic tube with a length of 3 cm(OD 5 mm, ID 4 mm) used to pack the entire assembly (Reprinted with permission from Wu et al. 2005. Copyright (2005) Institute of Physics)...

Sahoo, N.G., et al. Influence of carbon nanotubes and polypyrrole on the thermal, mechanical and electroactive shape-memory properties of polyurethane nanocomposites.Co/zzpo5.5cz. Technol. 2007, 67(9), 1920-1929. 

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