Applications of ICP-Based Materials

The number of potential applications of ICPs is almost unlimited due to their special features such as light weight, flexibiHty, mechanical properties, and tuneable conductivities that lie between insulators and metaUic conductors [110,111]. However, difficulties with the processabiHty of ICPs has hindered their commercial success. During the past 10 years, a wide variety of processable ICPs has been developed, with some becoming commercially available (Table 6.1). 

Panipol Panipol Ltd. (Finland) Polyaniline powders and dispersions Corrosion protection, antistatic, electro-chromic windows, EMI shielding 

Ormecon Ormecon Chemie, Germany Polyaniline dispersions Corrosion protection, antistatic coatings 

Eeonomer Eeonyx Corporation, USA Polyaniline /polypyrrole-coated carbon powders Static dissipative applications 

ConQuest DSM, The Netherlands Polypyrrole-coated latexes, powders Corrosion protection, antistatic, electrostatic discharge 

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The studies presented above indicate that sterilization has no detrimental effect on the abflity of ICPs to support the growth of a range of cell types. However, very little is known about the effects of sterilization on the electronic and redox properties of the ICPs. One paper by Campbell et al. [12] showed that sterilization using autoclaving had little effect on the ICP conductivity. The conductivity and redox properties of ICPs are two features that make them an attractive material in biomedical applications. For example, the inherent electrical conductivity of ICPs opens up the possibility of altering the cell-growth characteristics of ICP-based materials by the application of electrical stimulation. Therefore, it is crucial to evaluate their electrical and redox properties subsequent to sterilization. 

Nevertheless, some of the above mentioned applications and rationale behind using CPs/ICPs-based materials for them have been briefly discussed in the following section. 

Figure 1.66 Some application of CP/ICPs-based materials (a) DSSC, (b) photocatalysis, (c) thermoelectrics, (d) thin-film transistors, (e) electrorheological fluids, (f) memory devices, (g) actuators, (h) strain sensor, and (i) EC windows.

Laser based mass spectrometric methods, such as laser ionization (LIMS) and laser ablation in combination with inductively coupled plasma mass spectrometry (LA-ICP-MS) are powerful analytical techniques for survey analysis of solid substances. To realize the analytical performances methods for the direct trace analysis of synthetic and natural crystals modification of a traditional analytical technique was necessary and suitable standard reference materials (SRM) were required. Recent developments allowed extending the range of analytical applications of LIMS and LA-ICP-MS will be presented and discussed. For example ... 

Trace impurities in noble metal nanoclusters, used for the fabrication of highly oriented arrays on crystalline bacterial surface layers on a substrate for future nanoelectronic applications, can influence the material properties.25 Reliable and sensitive analytical methods are required for fast multi-element determination of trace contaminants in small amounts of high purity platinum or palladium nanoclusters, because the physical, electrical and chemical properties of nanoelectronic arrays (thin layered systems or bulk) can be influenced by impurities due to contamination during device production25 The results of impurities in platinum or palladium nanoclusters measured directly by LA-ICP-MS are compared in Figure 9.5. As a quantification procedure, the isotope dilution technique in solution based calibration was developed as discussed in Chapter 6. 

Due to the lack of suitable standard reference material for quantification purposes in phospho-proteomics and metallomics, reliable calibration strategies were developed for the direct microlocal analysis of phosphorus and metals in protein spots and in thin sections of brain tissue using LA-ICP-MS.16,17,116 For quantification of analytical data, the application of a solution based calibration strategy was proposed with LA-ICP-MS6 and the simultaneous determination of P, S, Si, Al, Cu and Zn concentrations in human brain proteins (Alzheimer s disease) or for imaging thin... 

CRM for road dust (BCR-723) containing 81.3 2.5 Jg/kg Pt, 6.1 1.9 ig/ kg Pd, and 12.8 1.3 Jg/kg Rh, was introduced [49, 228]. It is widely used for quality control of results obtained in the analysis of environmental materials (e.g., airborne particulate matters, dusts, soils, and sediments). Comparison of results obtained using different analytical procedures and interlaboratory studies are recommended when there is a lack of suitable CRM (e.g., in examination of clinical samples). The use of standards based on real matrices (e.g., saliva, plasma, ultrafiltrates, and lung fluids) instead of synthetic solutions is recommended in such analyses. Difficulties with the identification and quantification of different metal species in examined samples make the reliability of results of great importance. The use of various instrumental techniques for examination of particular samples can be helpful. The application of chromatography, mass spectrometry, and electrochemistry [199] HPLC ICP MS and HPLC MS/MS [156] ESI MS and MALDI [162] micellar electrokinetic chromatography, NMR, and MS [167] AAS, ESI MS, and CD spectroscopy [179] SEC IC ICP MS and EC ESI MS [180] and NMR and HPLC [229] are examples of such approaches. 

As a result, no mouldable or otherwise processable, ICP raw material was available outside our laboratories for broad-based applications-oriented research, so that application ideas (for which films could not be used) either failed to emerge at all, or were not investigated, or remained confined to the most obvious of fields such as replacement of carbon black in antistatic applications . 

In further quest for development of more efficient materials, clue had been provided by ongoing mixed (interdisciplinary) research. Intelligently the immediate inspiration was drawn from mixed systems (i.e., blends, alloys or composites) based on conventional polymers, metals, and ceramics. Soon it was realized that the already established wide applicability of CPs/ICPs can be further expended by formation of multiscale/multiphase systems, e.g., a wide variety of electronically, electrochemically, and/or optoelec-tronically active blends (BLNs), conjugated copolymers (CCPs) and composites (CMPs) [both bulk or nanocomposites (NCs)] or hybrids (HYBs) [11,14-16,52,109,113,120,128,131,132,191-205]. The next section of the chapter covers the fundamental aspects of CP-based BLNs, CCPs, and NCs/ HYBs. In particular, their definitions (including etymology), types, properties, synthetic routes, and practical applications have been discussed with the help of suitable examples from the open literature. 

The second way to enhance the usability of ICPs is to apply coatings thereof on textile materials. A very thin layer of conductive polymers can be applied on the surface of textile substrates by solution casting, inkjet printing, in situ polymerization, vapor phase polymerization, and chemical vapor deposition techniques [26—29]. The nano-microscale conductive coatings not only provide high level of conductivity but also preserve the flexibility and elasticity of substrate fibers. However, due to the health-related issues of some carbon-based materials one has to be observant about what is possible and what is not in apparel applications. 

Online isotope dilution technique LA-ICP-MS is proposed as the method of choice for quantitative element mapping and imaging even if no reference materials are available (42). For online solution-based calibration with LA-ICP-MS, a microflow total consumption nebulizer DS-5 (CETAC Technologies, Omaha, NE, USA) was inserted into the laser ablation chamber (21). It is more convenient to use solution-based calibration because such calibration can be performed easily, quickly and in any concentration range for many elements. The application of the online isotope dilution technique in LA-ICP-MS using a microflow nebulizer inserted into the laser ablation chamber to biological standard reference materials (e.g., apple leaves) yielded accurate analyte concentrations (42). 

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