Polyetheretherketone temperatures

Acrylic ESTER POLYMERS Acrylonitrile POLYMERS Cellulose esters). Engineering plastics (qv) such as acetal resins (qv), polyamides (qv), polycarbonate (qv), polyesters (qv), and poly(phenylene sulfide), and advanced materials such as Hquid crystal polymers, polysulfone, and polyetheretherketone are used in high performance appHcations they are processed at higher temperatures than their commodity counterparts (see Polymers containing sulfur). 

High-temperature TPs are available to compete with TSs, metals, ceramics, and other nonplastic materials. The heat-resistant TPs include polyetheretherketone (PEEK) and polyethersulfone (PES), polyamideimide, liquid crystal polymer (LCP) and others. 

Polyetheretherketone PEEK is a high-temperature, crystalline engineering TP used for high performance applications such as wire and cable for aerospace applications, military hardware, oil wells and nuclear plants. It holds up well under continuous 450°F (323° C) temperatures with up to 600°F (316° C) limited use. Fire resistance rating is UL 94 V-0 it resists abrasion and long-term mechanical loads. 

Polyetheretherketone, PEEK High temperature polymers CH063O0.16 0.029 1.60 0.001 0.008 17.0... 

The model PBZT/ABPBI molecular composite system is limited since the rod and the matrix do not possess glass transition temperatures for subsequent post form consolidation. In an effort to improve the processability for molecular composites, thermoplastics were used as the host matrix. Processing from acidic solvents requires the thermoplastic host to be soluble and stable in meth-anesulfonic add. Thermoplastic matrices were investigated including both amorphous and semicrystalline nylons [71,72], polyphenylquinoxaline (PPQ) [73] and polyetheretherketone (PEEK) [74], Table 5 shows the mechanical properties obtained for various processed PBZT thermoplastic molecular composite systems. As an example, the PBZT/Nylon systems showed 50-300% improvement over uniaxially aligned chopped fiber composite of comparable compositions. However, the thermally-induced phase separation during consol-... 

Today a stopped-flow instrument consists of oifly the unit itself combined with a diode array detector and a computer allowing fast kinetic measurements of time-resolved UV-vis spectra under anaerobic, high pressure and/or low temperature conditions. Improvements have been made as well, for example, syringes are installed vertically instead of horizontally (to avoid problems with gas bubbles) and polyetheretherketone (PEEK) is used instead of Teflon for valves and flow tubes to improve the anaerobic capabilities of the instrument. Further, the syringe drives setup was optimized. Application of rapid-scan devices (usually, but not exclusively, diode arrays) allows complete spectra to be collected at very short time intervals during a reaction. 

Melt processable, crystalline, high temperature polymers such as polyetheretherketone (PEEK) have been developed for critical application areas where processability, chemical resistance and toughness are required. PEEK has been applied as thermo-... 

Digestion is usually performed in a solution at specified conditions of pH, temperature, and buffer (see T able 1) and in a denaturing environment to ensure complete endpoint digestion. Volatile buffers such as ammonium carbonate and ammonium bicarbonate are preferred because they can be easily removed by lyophilization. A practical method for the removal of a nonvolatile buffer and salts is to use solid-phase extraction (SPE) cartridges prior to mass spectrometry analysis. One can also use immobilized trypsin packed into a small-diameter PEEK (polyetheretherketone) column or covalently attached to an activated MALDI probe for on-probe digestion.15... 

A particular drawback of the polyimides is that they have limited resistance to hydrolysis and may crack in water or steam at temperatures above 100°C. Consequently, polyimides have encountered competition from polyetheretherketones (PEEK), which are not only superior in this regard but are also easier to mold. 

Heat resistance can be divided into short term such as soldering temperature resistance and long term such as maximum continuous usage temperature, or so called UL (Underwriters Laboratory) thermal index. Types I and II have been granted a 240 C index by UL. This is equivalent to PEEK (polyetheretherketone), and is superior than PES (polyethersulfone), PEI (polyetherimide) and PPS (polyphenylenesulfide). 

PCFC results Temperature at peak mass loss rate obtained from derivative TGA curves PC - polycarbonate PEEK - polyetheretherketone PI - polyimide Reproduced with permission from H. Zhang, P.R. Westmoreland, R.J. Harris, E.B. Coughlin, A. Plichta and Z.K. Brozowski, Polymer, 2002, 43, 5463. 2002, Elsevier [78] ... 

Reaction of the dipotassium salt of hydroquinone with 4,4 -difluorodiphenyl ketone yields the high-temperature resistant plastic polyetheretherketone (PEEK). 

Hanchi J, Eiss NS, Dry sliding friction and wear of short carbon-fiber-reinforced polyetheretherketone (PEEK) at elevated temperatures. Wear, 203, 380-386, 1997. 

May, R. Victrex aromatic polymers for high temperature application. Proc. 7 Annu Des. Ing. Conf., Birmingham, 25-27 Sept, 1984 Kempston, 1984. P. 313-318. Shinyama, K., Fujita, S. Dielectric and thermal properties of irradiated polyetheretherketone IEEE Trans. Dielec, and Elec. Insul.. 2001. 8, N 3, c. 538-542. Hamciuc, Comeliu, Bruma, Maria, Klapper, Marcus Sulfonated poly(ether-ketone)s containing hexafluoroisopropylidene groups J. Macromol. Sci. A. 2001. 38, N 7, P. 659-671. 

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