Resist applications

Fig. 31. An acrylic terpolymer designed for chemically amplified resist applications. The properties each monomer contributes to the final polymeric stmcture are for MMA, PAG solubility, low shrinkage, adhesion and mechanical, strength for TBMA acid-cataly2ed deprotection and for MMA, aqueous...

The markets for polyetherimides arise to an extent from stricter regulations concerning flammability and smoke evolution coupled with such features as high strength, toughness and heat resistance. Application areas include car under-the-bonnet uses, microwave equipment, printed circuit boards and aerospace (including carbon-fibre-reinforced laminated materials). The polymer is also of interest in flim, fibre and wire insulation form. 

Because of their favourable price, polyesters are preferred to epoxide and furane resins for general purpose laminates and account for at least 95% of the low-pressure laminates produced. The epoxide resins find specialised uses for chemical, electrical and heat-resistant applications and for optimum mechanical properties. The furane resins have a limited use in chemical plant. The use of high-pressure laminates from phenolic, aminoplastic and silicone resins is discussed elsewhere in this book. 

Both TDI/MOCA and MDI/diol prepolymer systems are of importance for harder grades of printer s rollers and the wear-resisting applications such as pipes, pumps and impellers used in the mining and quarrying industries. 

In general, the thermoplastic elastomers have yet to achieve the aim of replacing general purpose vulcanised rubbers. They have replaced rubbers in some specialised oil-resistant applications but their greatest growth has been in developing materials of consistency somewhat between conventional rubbers and hard thermoplastics. A number of uses have also been developed outside the field of conventional rubber and plastics technology. 

Lead for Corrosion Resistant Applications, Lead Industries Association Inc., New York... 

Niobium like tantalum relies for its corrosion resistance on a highly adherent passive oxide film it is however not as resistant as tantalum in the more aggressive media. In no case reported in the literature is niobium inert to corrosives that attack tantalum. Niobium has not therefore been used extensively for corrosion resistant applications and little information is available on its performance in service conditions. It is more susceptible than tantalum to embrittlement by hydrogen and to corrosion by many aqueous corrodants. Although it is possible to prevent hydrogen embrittlement of niobium under some conditions by contacting it with platinum the method does not seem to be broadly effective. Niobium is attacked at room temperature by hydrofluoric acid and at 100°C by concentrated hydrochloric, sulphuric and phosphoric acids. It is embrittled by sodium hydroxide presumably as the result of hydrogen absorption and it is not suited for use with sodium sulphide. 

Jones, R. D. and Jones, D. P., Hot-dip Aluminized Steel Strip for Corrosion Resistant Applications , in Surface Treatment for Corrosion and Wear Resistance, Strafford, Datta and Googen (eds), Ellis Horwood, Chichester (1984)... 

Phenol-formaldehyde (phenolic) plastics The chemical resistance is affected by the phenol used, cresols giving the best acid resistance whilst xylenols are often used to obtain the best alkali resistance. For chemical-resistant applications the fillers used in moulding powder and reinforcing material in laminates should be inorganic, e.g. asbestos or glass. The resins are usually dark in colour. 

Chemical-resistant Highest chemical resistance of polyester group excellent acid resistance, fair in alkalies. Corrosion-resistant applications, such as pipe, tanks, ducts, fume stacks. 

Even though potential memory exists in all TPs, polyolefins, neoprenes, silicones, and other cross-linkable TPs are example of plastics that can be given memory either by radiation or by chemically curing. Fluorocarbons, however, need no such curing. When this phenomenon of memory is applied to fluorocarbons such as TFE, FEP, ETFE, ECTFE, CITE, and PVF2, interesting high-temperature or wear-resistant applications become possible. 

The market for silicon nitride is fast growing, particularly in structural and chemical resistance applications and as a thin film in semiconductor devices.P 1... 

Intermediate layer in corrosion- and erosion-resistant applications. 

Experimental TiB2 coatings for cemented carbide cutting tools and other wear- and erosion-resistant applications (pumps, valves, etc.). ]... 

CVD in Wear- and Corrosion-Resistant Applications 441 CVD Nitrides for Corrosion-Resistant Applications... 

Other CVD Corrosion-Resistance Applications. The following is a listing of typical applications where CVD is used either in production or experimentally for corrosion protection. 

Melamine fiber is mainly used in heat- and flame-resistant applications, especially in the manufacture of protective clothing for the iron, steel, and automobile industries, in aircraft and... 

D. Cattell, Polymers in Chemically Resistant Applications, Rapra Review Reports 39, Rapra Technology, Shawbury (1991). 

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