Polyetheretherketone PEEK Resin

This polymer is formed by the reaction of hydroquinone, 4,4 -difluorobenzophenone and potassium carbonate in diphenylsulfone at 150-300°C. 

Earlier, small amounts of the diphenylsulfone solvent may have remained in the polymer, but over the last decade, product purity has significantly improved. The weight average molecular weight is 30,000 and the number average molecular weight Mj = 13,000. The repeat unit is nineteen C atoms, twelve H atoms and three O atoms giving a total 

PEEK has a high melting point (334°C), but provided oxygen is excluded, it will withstand 400°C for more than one hour. Although a maximum service temperature of 120°C would be appropriate for a material with a Tg of 143°C, the maximum working temperature is extended well above the Tg since crystalline resins are self-supporting up to the melting point. 

PEEK has outstanding chemical resistance and low water absorption, although it is always recommended to dry for at least 3 h before use. PEEK has become a very important matrix for producing cfrp composites. 

Failure mechanisms in carbon fiber reinforced PEEK have been studied [134—137]. The importance of a strong fiber/matrix bond has been shown to be a dominant factor in conferring maximum composite toughness [138 140]. Variation of the fiber content changes the role of the matrix phase and the ductilty of the matrix controls the fracture behavior. 

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Engineering thermoplastics have also been used in preimpregnated constructions. The thermoplastic is thoroughly dispersed as a continuous phase in glass, other resins, carbon fibers (qv), or other reinforcement. Articles can be produced from these constructions using thermoforming techniques. For example, the aerospace industry uses polyetheretherketone (PEEK) in woven carbon-fiber tapes (26). Experimental uses of other composite constructions have been reported (27) (see also COMPOSITE MATERIALS, POLYMER-MATRIX). 

The 1950s gave rise to the polypropylenes and polycarbonates. Other engineering resins such as Polyetheretherketone (PEEK) and polysulfones were developed later. 

Amorphous PEEK (polyetheretherketone) thermoplastic resins had much lower water uptakes and the ATg was limited to just 2°C. The more usual semi-crystalline PEEK, that is, the form commercially available, has an even greater resistance to water absorption and therefore an even greater stability in wet conditions, but it suffers from a high cost disadvantage. 

The family of PKs, also called polyaryletherketones (PAEKs), consists of polyetheretherketone (PEEK), polyetheretherketone-ketone (PEEKK), polyetherketone (PEK), and polyetherketone-etherketone-ketone (PEKEKK). They share similar molecular structures based upon repeating ether and ketone groups in various ratios. Cost of the resins is high but, in RPs with high-performance fibers, there are many appfications in the aerospace and defense industries, electrical and atomic installations, and industrial and electronics products. Compoimds for injection molding are available, but the major area of apphcation is with thermoplastic prepreg materials, using mats, fabrics and/or continuous fiber. 

Synthetic thermosetting polymers used in the construction industry are polyester, vinylester and epoxies these materials are generally used to manufacture parts of the machines that produce sustainable energy generators. In addition, thermoplastic resins, such as polyetheretherketone (PEEK), polyethersulphone (PES) and various liquid crystal polymers (LCP) are also used. The latter high performance polymers also meet stringent out-gassing (relevant to space environments) and flammability requirements. 

Depending on the application, different matrix materials are used. Among the duromers, most common are polyester and epoxy resins. Thermoplastic matrix materials are polyethylene (pe) and polypropylene (pp), but the use of thermoplastics with aromatic rings on the chain and thus with increased temperature stability also grows. One example is polyetheretherketone (peek), characterised by high toughness and a glass temperature of about 150°C. 

Thermoplastic matrices may also be used with the microdrop method [58,61] A method to form thermoplastic matrix material microdrops in various fiber-thermoplastic systems has been reported by Gaur et al. [58]. They measured the interfacial shear strength of carbon and aramid fibers embedded in four thermoplastic resins polyetheretherketone (PEEK), polyphenylene sulfide (PPS),... 

Solvay s Amodel PPA resin features an excellent stil3iiess-to-cost ratio and a high strength-to-weight ratio, both of which are superior relative to PBT, PPS, PEI, PET and PA 6,6. Its thermal performance is exceeded only by polyetheretherketone (PEEK) and some LCPs its warpage and dimensional stability match PPS. Amodel resin has lower moisture absorption than PA 6,6, and its broad chemical resistance is exceeded only by a handful of more costly speciality polymers. 

The most widely used and least expensive polymer resins are the polyesters and vinyl esters. These matrix materials are used primarily for glass fiber-reinforced composites. A large number of resin formulations provide a wide range of properties for these polymers. The epoxies are more expensive and, in addition to commercial applications, are also used extensively in PMCs for aerospace applications they have better mechanical properties and resistance to moisture than the polyesters and vinyl resins. For high-temperature applications, polyimide resins are employed their continuous-use, upper-temperature limit is approximately 230°C (450 F). Finally, high-temperature thermoplastic resins offer the potential to be used in future aerospace applications such materials include polyetheretherketone (PEEK), poly(phenylene sulfide) (PPS), and polyetherimide (PEI). 

Polyetheretherketone Resin (PEEK). The resia was commercialized as Victrex PEEK by Imperial Chemical Industries, Ltd. (ICl) ia the late 1970s and by Amoco Chemicals Corp. ia the middle 1980s under the trade name Kadel. It is produced by both companies ia the United States. Kadel is beheved made by the displacement reaction of 4,4 -difluorodiphenyl ketone by the potassium salt of hydroquinone ... 

A helical blade used in fluid compressors made of plastics, such as PTFE, PFA (perfluoroalkoxy resin), PEEK (polyetheretherketone), PES (polyether sulfone). 

Polyetherketone n. An advanced thermoplastic resin having both ether and ketone linkages in its chains, a close relative of polyetheretherketone, above, and having the peek structure with the leftmost phenyl and ether oxygen deleted. This melt-processable polymer melts near 365°C, is... 

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