Polymers sensor materials

Composition materials ineluding indieator reagent and bearer have been investigated as sensor materials. It has been found out that nature of beai er (sorbent or polymer film) is of the main signifieanee. Siliea gel, aluminium oxide, porous glass, polyurethane, polyvinylehloride ete have been investigated as beai ers. 

Successful development of fibre optic chemical sensors requires the cooperation of many specialists in various fields of science. Scientists in analytical chemistry, polymer science, material science, optoelectronics and electronics etc. can be involved in this multidisciplinary task. Depending on the application of the sensor biologists, medical doctors or environmentalists can also be incorporated to the working group. Although, the contribution of all specialists cannot be classified by the importance, analytical chemistry and material science seem to be the key to the success. 

Mohr G.J., Werner T., Oehme I., Preininger C., Klimant I., Kovacs B., Wolfbeis O.S., Novel optical sensor materials based on solubilization of polar dyes in apolar polymers. Advanced materials 1997 14 1108-1113. 

We have shown a new concept for selective chemical sensing based on composite core/shell polymer/silica colloidal crystal films. The vapor response selectivity is provided via the multivariate spectral analysis of the fundamental diffraction peak from the colloidal crystal film. Of course, as with any other analytical device, care should be taken not to irreversibly poison this sensor. For example, a prolonged exposure to high concentrations of nonpolar vapors will likely to irreversibly destroy the composite colloidal crystal film. Nevertheless, sensor materials based on the colloidal crystal films promise to have an improved long-term stability over the sensor materials based on organic colorimetric reagents incorporated into polymer films due to the elimination of photobleaching effects. In the experiments... 

Malitesta C, Losito I, Zambonin PG. Molecularly imprinted electrosynthesized polymers new materials for biomimetic sensors. Anal Chem 1999 71 1366-1370. 

CMPO, the selective extractant chemistry in TRU-Resin, can be impregnated into polymers that also contain organic fluor molecules to develop sensor materials, as described previously for crown ether and liquid anion-exchange chemistry. Actinide sensing by this approach has been described.96 135 137 Such sensor chemistries have potential for use in the development of on-line monitors. 

In the near future, the use of multifunctional polymer-based materials with separation/selective transport capabilities is also to be expected in the design of production systems with integrated environmental protection or inthe combination of chemical reactions and separation by attaching a catalytic functionality to the respective material [1]. Thus, those multifunctional materials should contribute materially to the development of clean energy and/or energy saving and therefore sustainable production technologies. In connection with these perspectives, there is considerable interest in new/modified polymer-based materials with tailored transport/catalytic properties. Also, many sensor applications are based on controlled permeation. 

B-2000MI1 Y. Osada and D. E. DeRossi, Eds. Macromolecular Systems, Materials Approach Polymer Sensors and Actuators ,... 

Single-walled carbon nanotubes, SWNT, having a diameter of 0.7 nm were electro-chemically derivatized on the sides and ends with diazonium tetrafluoroborate derivatives. In this process the estimated degree of functionality was about 1 out of every 20 to 30 carbons in the nanotube. These chemically modified nanotubes have applications in polymer composite materials, molecular electronic applications, and sensor devices. 

The availability of various functional monomers is essential to operate molecular imprinting by a combinatorial method. Therefore, efforts to design and synthesise novel functional monomers have been made for developing a desired specificity and functions [2,3, 27]. With a wide selection of functional monomers, further functionalised polymers, such as catalysts and sensor materials, will also be developed by the combinatorial chemistry-based molecular imprinting. 

Nieuwenhuizen and Harteveld [92] have realized a nerve agent dosimeter gas sensor based on the strong interaction between certain metal ions and organophosphorus compounds. In this case, the sensor material contains La(III) 2-bis(carboxymethyl)amino hexadecanoic acid and different factors such as humidity, concentration and layer thickness have been studied and optimized. Using a combination of a metallic complex with a molecular-imprinted polymer, a very sensitive sensor was developed for the detection of soman, a chemical warfare agent (the detection limit was 7 ppt) [93]. The biosensing material is based on a polymer coated onto a fiber-optic probe modified with a luminescent europium detection complex. This complex was... 

Potyrailo, R. A. Leach, A. M., Gas sensor materials based on semiconductor nanocrystal/ polymer composite films, In Proceedings of Transducers 05, the 13th International Conference on Solid-state Sensors, Actuators and Microsystems, Seoul, Korea, June 5-9, 2005 1292-1295... 

As expected, solutions containing mixtures of nanocrystal sizes exhibited spectral profiles corresponding to the sum of the spectra of the individual sizes (Fig. 5.3). The initial PL peak positions of 2.8 and 5.6-nm CdSe nanocrystals in toluene solution were at 541 and 636 nm, respectively. We incorporated the CdSe nanocrystal mixtures into polymer matrices rationally selected based on polymer-sensing properties (Table 5.1). CdSe nanocrystals exhibited spectral shifts upon their immobilization in polymer films and photoactivation with the 407-nm diode laser. Photoactivation is an important aspect of the performance of the CdSe and other semiconductor crystals as chemical sensor materials.16 Different spectral shifts of steady-state PL emission and different emission intensity were observed upon incorporation of the 2.8 and 5.6-nm CdSe nanocrystals in polymer films as illustrated in Fig. 5.4. Polymer 2 (PMMA) was selected for the detailed evaluation because it has been used previously as a matrix for incorporation of CdSe nanocrystals.1636... 

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