Since production volumes are very limited with 20.000 t/year the high-performance plastics are holding a market share of just about 1%. Also in future there cannot be expected a significant price decline, since the investment costs for production equipment, the time-consuming development and the high distribution costs are High-performance plastics are thus about 3 to 20 times as expensive as engineering plastics. The average value is slightly less than 15 US-Dollar/kg. High performance plastics are relatively expensive: The price per kilogram may be between $5 (PA 46) and $100 ( PEEK). Some of their diverse applications include: fluid flow tubing, electrical wire insulators, architecture, and fiber optics. heat stability), in contrast to engineering plastics which provide moderate performance over a wider range of properties. Most high-performance plastics are exploited for a single property (e.g. Especially the latter makes processing difficult, often requiring specialized machinery. High performance plastics meet higher requirements than standard and engineering plastics because of their more desirable mechanical properties, higher chemical and/or a higher heat stability. The development of new high-performance plastics is therefore closely linked to the development and economic production of the constituent monomers. In addition, the stereochemistry plays a role in achieving the desired properties in general. In manufacturing processes by polycondensation a high purity of the starting materials is important. For this reason, the majority of high-performance plastics is nowadays produced by polycondensation processes. Since electrophilic synthesis has in general the disadvantage of a low selectivity to linear polymers and is using aggressive reactants, the product could hold only a short time on the market. PEK was offered since 1972 by Raychem, however, made by an electrophilic synthesis. A production of PEEK (ICI), PEK (ICI) and PEI (General Electric and GE) via polycondensation was developed in the 1970s. The market entry took place in the early 70s. Synthetic routes for example for PPS, PES and PSU were developed in the 1960s by Philips, ICI and Union Carbide. Since the early 1960s, the development of high-performance plastics has been driven by corresponding needs in the aerospace and nuclear technology. The improvement of mechanical properties and thermal stability is and has always been an important goal in the research of new plastics. However, the differentiation from less powerful plastics has varied over time while nylon and poly(ethylene terephthalate) were initially considered powerful plastics, they are now ordinary. Thermosets and elastomers are outside of this classification and form their own classes. If the term "high-performance thermoplastics" is used, it is because both standard and technical as well as high-performance plastics are always thermoplastics. The term " polymers" is often used instead of "plastics" because both terms are used as synonyms in the field of engineering. The name high temperature plastics is in use due to their continuous service temperature (CST), which is always higher than 150 ☌ by definition (although this is not their only feature, as it can be seen above). There are many synonyms for the term high-performance plastics, such as: high temperature plastics, high-performance polymers, high performance thermoplastics or high-tech plastics. High performance plastics differ from standard plastics and engineering plastics primarily by their temperature stability, but also by their chemical resistance and mechanical properties, production quantity, and price. See also: Plastic § Special purpose plastics
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