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Polyetheretherketone (PEEK) is a polymer containing a ketone bond and two ether bonds in the main chain structure of the repeating unit, is a special polymer materials. It has high temperature resistance, chemical resistance and other physical and chemical properties, is a class of semi-crystalline polymer materials, can be used as high temperature resistant structural materials and electrical insulation materials, and can be compounded with glass or carbon fibres to prepare reinforcing materials. It is generally used as a class of polyaryl ether polymers obtained by condensation with aromatic diphenols. This material has a large number of applications in aerospace, medical devices (as artificial bone to repair bone defects) and industry.

PEEK (polyetheretherketone) plastic material is an aromatic crystalline thermoplastic polymer material with high mechanical strength, high temperature resistance, impact resistance, flame retardancy, acid and alkali resistance, hydrolysis resistance, wear resistance, fatigue resistance, irradiation resistance and good electrical properties.
High temperature resistance: It has a high glass transition temperature (Tg=143°C) and melting point (Tm=343°C), its load heat deflection temperature is up to 316°C and the instantaneous use temperature is up to 300°C.
Mechanical properties: rigid and flexible, particularly outstanding fatigue resistance under alternating stress, comparable to alloy materials.
Self-lubricating: excellent sliding characteristics, suitable for strict requirements of low coefficient of friction and wear-resistant applications, especially with carbon fibres, graphite each in a certain proportion of the mixture of modified PEEK self-lubricating properties better.
Corrosion resistance: In addition to concentrated sulfuric acid, PEEK is insoluble in any solvent and strong acids, strong alkalis, and resistant to hydrolysis, with high chemical stability.
Flame retardant: self-extinguishing, even without any flame retardant, can reach UL standard 94V-0 level.
Easy processing: With good high temperature fluidity and high thermal decomposition temperature, it can be processed in various ways: injection moulding, extrusion, moulding and melt spinning etc.
Peel resistance: excellent peel resistance, so it can be made into very thinly covered wires or electromagnetic wires and can be used under harsh conditions.
Fatigue resistance: the best fatigue resistance of any resin.
Irradiation resistance: Highly resistant to high levels of irradiation, surpassing polystyrene, which has the best irradiation resistance of any general purpose resin. It can be made to maintain good insulation performance at gamma irradiation doses of up to 1100Mrad.
Hydrolysis resistance: PEEK and its composites are chemically unaffected by water and high-pressure water vapour, and products made from this material retain their excellent properties when used continuously in high-temperature and high-pressure water.
Smoke generation: PEEK has the lowest smoke generation of any plastic.
Toxic fugacity: PEEK, like many organic materials, produces mainly carbon dioxide and carbon monoxide when decomposed at high temperatures. The Toxicity Index is defined as the ratio of the combined concentration of toxic gases produced under normal conditions to the dose that would be fatal in 30 minutes, PEEK450G has an index of 0.22 and no acidic gases were detected.
Insulation Stability: PEEK450G has good electrical insulation properties and maintains them to a very high temperature range. Its dielectric losses are also small at high frequencies.
Stability: has superior dimensional stability characteristics, which are important for some applications. Changes in temperature, humidity and other environmental conditions have little effect on the dimensions of PEEK parts, and can meet the requirements of high dimensional accuracy in the workplace.
(1) PEEK plastic raw material injection molding shrinkage is small, which is very good for controlling the range of dimensional tolerances of PEEK injection molded parts, so that the dimensional accuracy of PEEK parts is much higher than that of general-purpose plastics;
(2) small coefficient of thermal expansion, with changes in temperature (can be caused by changes in ambient temperature or frictional heat generation during operation), the size of PEEK parts change very little;
(3) good dimensional stability, the dimensional stability of plastics refers to engineering plastics products in use or storage in the process of dimensional stability of performance, this change in size is mainly due to the activation energy of polymer molecules increased, so that the chain segments have some degree of curl caused by; (4) PEEK heat resistant hydrolysis, the PEEK parts are not the same;
(4) PEEK heat-resistant hydrolysis properties outstanding, in high temperature and high humidity environment, water absorption is very low, will not appear similar to nylon and other general-purpose plastics due to water absorption and size change significantly.