Specialty applications

Natural product-derived dispersants, such as tannins, lignins, and alginates, are still widely used as drilling mud thinners or in specialty applications where their low toxicity is a cmcial property, eg, in boilers producing steam for food applications. 

Clean Air Machine Corp. Air purifiers - commercial site offers customized filters for specialty applications aimed at removal of microscopic particulates and gases. http //aco.ca/tibbits/index. html... 

Synthetic paper now targets high-priced specialty applications that include beverage labels, restaurant menus, drivers licenses, recipe books, instruction manuals, maps, and book jackets. 

The acid chloride route of the Schotten-Baumann reaction can be carried out continuously [6] while completeness of the reaction can be assured by rapid recirculation of the reaction product [7]. These compounds are used in specialty applications, such as shampoos or soap-syndet toilet bars [8]. 

Recently, as a further recognition of the importance of multiphase copolymers in specialty applications, siloxane containing block and segmented copolymers have received special attention for applications such as biomaterials, photoresists, gas separation membranes, protective coatings, elastomers and emulsifiers, as we shall... 

Puskas, J.E., Kumar, B., Ebied, A., and Lamperd, B. Novel Butyl Composites for Less-Lethal Ammunition. Papei 126, ACS Rubber Division, 164th Technical Meeting, October 14—17, Cleveland, OH, 2003. Puskas, J.E., Kumar, B., Ebied, A., and Lamperd, B. Comparison of the Performance of Vulcanized Rubbers and Elastomer/TPE Composites for Specialty Applications. Proceedings of the Polymer Processing Society, 2004. 

Chemical reactions are used to modify existing polymers, often for specialty applications. Although of considerable importance for plastics, very few polymer reactions (aside from crosslinking) are important for elastomers. Chlorination and bromination of Butyl rubber to the extent of about one halogen atom per isoprene unit yields elastomers which are more easily crosslinked than Butyl rubber. Substitution occurs with rearrangement to yield an allylic halide structure... 

All these capabilities enable to address the search for new enzymes for specialty applications, such as thermostable and solvent resistance enzymes. A viscosity improving thermostable enzyme family (Pyrolase 160 and Pyrolase 200, the later working at higher temperatures) was designed for use in deep and high temperature oil wells. Sales of this product commenced in January 1999, but were discontinued later. 

The second and the third papers of this chapter were contributed by Bulgaria s National Academy of Sciences distinguished developers, Dr. A. Kaisheva and Professor I. Iliev. The two papers address magnesium-air and zinc-air chemistries, respectively. Concepts of mechanical recharging, new non-KOH based electrolytes, and the role of carbon materials in cell design have been thoroughly studied. Authors have reduced to practice their many developments. Systems created work(ed) in many specialty applications. 

There are no electrolyzers developed specifically for operation with wind turbines. However, the rapid response of electrochemical systems to power variations makes them suitable "loads" for wind turbines. Industrial electrolyzers are designed for continuous operation, mainly because their elevated investment cost requires high-capacity factors for reasonable payback times, but they are subject to a considerable number of current interruptions through their lifetime due to occasional power interruptions, accidental trips of safety systems, and planned stops for maintenance. Current interruptions are more frequent in specialty applications, where electrolyzers supply hydrogen "on demand." Therefore, the discontinuous use of the equipment is not new, and most commercial electrolyzers may be used in intermittent operation although a significant performance decrease is expected with time. In fact, it is not power variation, but current interruptions that may cause severe corrosion problems to the electrodes, if the latter are not protected by the application of a polarization current when idle. 

These materials have possible utility in a number of specialty applications and are being explored by Guan et al. [37], They have used these catalysts, and their unique chain-walking characteristics to synthesize a variety of dendritic materials (Fig. 4), which could find potential application as processing aids, rheological modifiers, and amphiphilic core-shell nanoparticles for drug delivery and dye formulation. 

A solid electrolyte is an ionic conductor and an electronic insulator. Ideally, it conducts only one ionic species. Aside from a few specialty applications in the electronics industry, solid electrolytes are used almost exclusively in electrochemical cells. They are particularly useful where the reactants of the electrochemical cell are either gaseous or liquid however, they may be used as separators where one or both of the reactants are solids. Used as a separator, a solid electrolyte permits selection of two liquid or elastomer electrolytes each of which is matched to only the solid reactant with which it makes contact. 

The concluding section suggests alternative uses of agricultural products in nonnutritional areas first, as a source of monomers then as an alternate crop strategy, particularly under less-than-optimum farm conditions. Their suitability for both low-cost and specialty applications are considered, as well. 

Unfortunately these are expensive catalysts and they have not yet made a serious dent in the large-scale polymer market. However, specialty applications in food packaging, personal care, and medicine are being utilized. 

Turpentine is a mixture of CioHie volatile terpenes (hydrocarbons made of isoprene units). There are actually four different types and methods of making turpentine, including steam distillation of wood. The two pinenes, a and P, are major components of turpentine. Other compounds found in abundant amounts are camphene, dipentene, terpinolene, and A -carene. Although it has been replaced by petroleum hydrocarbons as paint thinners (lower price, less odor), turpentine is still a good solvent and thinner in many specialty applications. The use pattern for turpentine is as follows synthetic... 

Isocyanates that are produced fi om aliphatic amines are utilized in a limited range of polyurethane products, mainly in weatherable coatings and specialty applications where the yellowing and photodegradation of the aromatic polyurethanes are undesirable [5]. The aliphatic isocyanates are not used more widely in the industry due to the remarkably slow reaction kinetics of aliphatic isocyanates compared to their aromatic counterparts [6]. Due to the slow reactivity of aliphatic isocyanates, it is not practical to use them in the preparation of flexible or rigid foams, which are the main commercial applications for polyurethane chemistry. 

Although phenol itself is used in the largest volume, various substituted phenols such as cresol (o-, m-, p-), p-butylphenol, resorcinol, and bisphenol A are used for specialty applications. Some use is also made of aldehydes other than formaldehyde—acetaldehyde, glyoxal, 2-furaldehyde. 

Crosslinking of epoxy plastics through the hydroxyl groups of the repeat unit is used for prepolymers with low epoxide group contents. The most common curing agent is phthalic anhydride although other acid anhydrides such as tetrahydrophthalic, nadic methyl, and chloroendic anhydrides are used in specialty applications ... 

How do dendrimers and hyperbranched polymers compare from an industrial viewpoint Dendrimers offer the potential for producing polymers whose molecular size and structure are more regular and less polydisperse. 1 lyperbranched polymers are easier and cheaper to synthsize—a one-pot synthesis compared to the multipot synthesis for dendrimers. However, not too many AB/ monomers are readily available, and this may modify the overall economics. Hyperbranched polymers will probably find use in larger-scale or commodity applications where lower cost is a necessity and dendrimers in specialty applications where higher cost is justified. 

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