Polyether ketones/carbon

This semi-crystalline polymer belongs to the family of polyether ketones, Tg= 145 C Tm = 235 C. Developed in 1980 by ICI, it is a superb engineering polymer, showing excellent mechanical properties that are retained at elevated temperatures. Due to its extremely high price, its utility is still limited to the field of aviation and space (reinforced with carbon fibers), electronics and machinery. Another advantage is its stability towards fire or chemicals, although it is sensitive to UV radiation. 

Polyether ether ketone Carbon fiber — Molecular 58,59... 

Polymers used for seat and plug seals and internal static seals include PTFE (polytetrafluoroeth ene) and other fluorocarbons, polyethylene, nylon, polyether-ether-ketone, and acetal. Fluorocarbons are often carbon or glass-filled to improve mechanical properties and heat resistance. Temperature and chemical compatibility with the process fluid are the key selec tion criteria. Polymer-lined bearings and guides are used to decrease fric tion, which lessens dead band and reduces actuator force requirements. See Sec. 28, Materials of Construction, for properties. 

Other coupling reactions were also employed to prepare poly(arylene etherjs. Polymerization of bis(aryloxy) monomers was demonstrated to occur in the presence of an Fe(III) chloride catalyst via a cation radical mechanism (Scholl reaction).134 This reaction also involves carbon-carbon bond formation and has been used to prepare soluble poly(ether sulfone)s, poly(ether ketone)s, and aromatic polyethers. 

The primary resin of interest is epoxy. Carbon-fiber-epoxy composites represent about 90% of CFRP production. The attractions of epoxy resins are that they polymerize without the generation of condensation products that can cause porosity, they exhibit little volumetric shrinkage during cure which reduces internal stresses, and they are resistant to most chemical environments. Other matrix resins of interest for carbon fibers include the thermosetting phenolics, polyimides, and polybismaleimides, as well as high-temperature thermoplastics such as polyether ether ketone (PEEK), polyethersulfone (PES), and polyphenylene sulfide. 

Systematic studies on the chelation-controlled additions were carried out, varying the type of alkoxy group, the carbon nucleophile, the solvent and the temperature. It was found that a-alkoxy ketones react highly stereoselectively with Grignard reagents in THF (equation 24). Alkyllithiums were not effec-tive. -6 The generalization was made use of in the synthesis of the polyether antibiotic monensin. ... 

VI (a) Tricresyl phosphate, aliphatic ketones and esters, polyethers, (b) Sulfones, nitriles, propylene carbonate dioxane... 

Besides graphite, carbon and glass fibers, organic fibers, e.g., Kevlar, have also been used to reinforce thermosetting resins, e.g., epoxy resin (38). One of the newest developments is fiber-reinforced thermoplastics, e.g., carbon fiber-reinforced polyether ether ketone (PEEK) ( ). These materials are rather tough as demonstrated in the interlaminar toughness values (Table... 

Polyether ether ketone (PEEK) has poor resistance to UV. Reinforced grades are available and, where some degree of UV resistance is required, carbon black may be added. Polyphenylene oxide (PPO) and polysulfone are susceptible to photodegradation due to their aromatic content, although PPO in its usual form as a stabilized polymer alloy is somewhat better. It is inadvisable to use any of these polymers for prolonged exposure without protection. 

Wang A, Lin R, Polineni VK, Essner A, Stark C, Dumbleton JH, Carbon fiber reinforced polyether ether ketone composite as a bearing surface for total hip replacement. Tribology International, 31(11), 661-667, 1998. 

It is seen that many of these formulations are available in glass fibre or carbon fibre reinforced forms. Thus, polyether ether ketone (PEEK) is available in a 30% carbon fibre or in 20 or 30% glass fibre reinforced forms. Similarly, polysulfone (PSU) is available in a 30% carbon fibre or 10% glass-reinforced form. 

Polyether ether ketone Calcium carbonate Study of thermal and mechanical... 

Zhou et al. [173] studied the effects of surface treatment of calcium carbonate particles with sulfonated polyether ether ketone on the mechanical and thermal properties of composites with polyether ether ketone in various proportions prepared using a twin-screw extruder. These workers used tensile, impact, and flexural testing, thermogravimetric analysis, differential scanning calorimetry, and scanning electron microscopy. The influences of filler particle, loading, and surface treatment on deformation and crystallinity of polyether ether ketone were discussed. 

Calcium carbonate has also been used as a reinforcing agent for a range of polymers, including polyether ether ketone [174], acrylonitrile-butadiene-styrene terephthalate [175], polypropylene, and polydimethyl siloxane. 

Multiwalled carbon nanotube-polypropylene Multiwalled carbon nanotube-high-density polyethylene Multiwalled carbon nanotube-polyimides Single-walled carbon nanotube-vinylene Carbon nanotube-polyether ether ketone Multiwalled carbon nanotube-polycarbonate TjOj-coated multiwalled carbon nanotube-epoxy composites Carbon nanotube polyetherimide and epoxy resins Carbon nanotube polypyrrole... 

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