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Poly ketone modified

Nanofiltration membranes based on poly(ether ether ketone) modified with a mixture of ammonia with Ar or hydrogen show much better dye filtration parameters than the unmodified or commercial membranes (Buonomenna et al. 2009). [Pg.190]

Membranes and Osmosis. Membranes based on PEI can be used for the dehydration of organic solvents such as 2-propanol, methyl ethyl ketone, and toluene (451), and for concentrating seawater (452—454). On exposure to ultrasound waves, aqueous PEI salt solutions and brominated poly(2,6-dimethylphenylene oxide) form stable emulsions from which it is possible to cast membranes in which submicrometer capsules of the salt solution ate embedded (455). The rate of release of the salt solution can be altered by surface—active substances. In membranes, PEI can act as a proton source in the generation of a photocurrent (456). The formation of a PEI coating on ion-exchange membranes modifies the transport properties and results in permanent selectivity of the membrane (457). The electrochemical testing of salts (458) is another possible appHcation of PEI. [Pg.14]

Other organic—inorganic hybrids include poly(ethyloxazoline)—siUca, poly(vinyl alcohol)—siUca, poly(arylene ether) ketone—siUca, polyimide—siUca, polyozoline—sihca, poly(ethylene oxide)—siUca, and polymers—modified alkoxysilane. [Pg.260]

Poly(arylene ether ketone)s can also be modified by introducing the functional groups using similar approaches to polysulfones. For example, poly(arylene ether ketone)s were sulfonated.189 In addition, o-dibenzoylbenzene moieties in the poly(arylene ether)s can be transformed to heterocycles by cyclization with small molecules. These polymers can react with hydrazine monohydrate in the presence of a mild acid in chlorobenzene or with benzylamine in a basic medium.190 Another example of the use of the o-benzyl cyclization strategy is the intramolecular ring closure of poly(arylene ketone)s containing 2,2/-dibenzoylbiphenyl units to form poly(arylene ether phenanthrenes).191... [Pg.354]

Upadhyay et al. [98] used primarily correlated XPS and water contact angle measurements to study the surface degradation and recovery of amorphous films of a PMMA and a poly (aryl ether ether ketone) (PEEK). Surface modification of the films was carried out in a dielectric barrier discharge (DBD) unit, samples being treated with different dose levels of dielectric discharge. The modified (treated) samples were then stored for one month and re-examined. Figure 35 shows C(ls) and 0(1 s) XPS envelopes and their curve-fitting deconvolutions,... [Pg.434]

The HOPG (highly oriented pyrolytic graphite) carbon electrode chemically modified with (5[-phenylalanine at the basal surface led to 2% ee in the reduction of 4-acetylpyridine [377]. A cathode modified with a chiral poly(pyrrole) reduced 4-methylbenzophenone or acetophenone in DMF/LiBr and phenol as proton donor to 1-phenylethanol with up to 17% ee [382]. Alkyl aryl ketones have been reduced to the corresponding alcohols at a Hg cathode in DMF/water in the presence of (1R,2S)-A,A-dimethylephedrinium tetrafluorobo-rate (DET), producing (5 )-l-phenylethanol with 55% ee from acetophenone. Cyclovoltammetry supports an enantioselective protonation of the intermediate (PhCOH(CH3)) [383]. [Pg.441]

The most common way to modify aromatic polymers for application as a PEM is to employ electrophilic aromatic sulfonation. Aromatic polymers are easily sulfonated using concentrated sulfuric acid, fuming sulfuric acid, chlorosulfonic acid, or sulfur trioxide (or complexs thereof). Postmodification reactions are usually restricted due to their lack of precise control over the degree and location of functionalization, the possibility of side reactions, or degradation of the polymer backbone. Regardless, this area of PEM synthesis has received much attention and may be the source of emerging products such as sulfonated Victrex poly (ether ether ketone). [Pg.354]

Various materials have been examined for use as deep UV resists poly(methyl methacrylate) (PMMA) (1), poly(methyl isopropenyl ketone) (PMIPK) fS.7L and the novolak-Meldrum s acid solution inhibition system (S). Each however has a problem related to sensitivity and/or resolution. While PMMA is insensitive to light of X > 230 nm because of its weak absorption, its high resolution properties make it an attractive starting point for the design of a resist that will perform well in the 230-280 region. The photochemical properties of PMMA could be modified by the incorporation of a small percentage of photolabile groups so as to have both the desired sensitivity and base polymer properties. [Pg.29]

A new series of functionalized poly(arylene ether ketone)s and their use as modifiers for bismaleimide resins has recently been published (96). In contrast with the former work in this area, the functional groups are not terminal but randomly distributed along the backbone of the poly(arylene ether ketone). The synthesis involves the reaction of 4,4 -difluorobenzophenone and the potassium bisphenates of bisphenol-A and 2,2 -bis(3-allyl-4-hydroxyphenyl) hexafluoro-isopropane or mixtures thereof in DMAc at 155 °C as outlined in Fig. 31. The concentration of the o,o -diallylbisphenol employed in the synthesis determines the concentration of functional propenyl groups. [Pg.197]

The synthesis of poly(vinyl acetals) (252) represents another example of generating a heterocycle, in this case the 1,3-dioxane nucleus, by application of a polymer modification reaction. Generally, the polymer modified is poly(vinyl alcohol) (180) or one of its copolymers. The 1,3-dioxane ring is generated (Scheme 122) by an acid-catalyzed acetalization reaction with an aldehyde, although ketones have also been reacted. A review (71MI11102) is available covering synthesis, properties and applications of the two most common and industrially important poly(vinyl acetals), poly(vinyl butyral) and poly(vinyl formal), as well as many other functional aldehydes that have been attached. [Pg.315]

MC MDI MEKP MF MMA MPEG MPF NBR NDI NR OPET OPP OSA PA PAEK PAI PAN PB PBAN PBI PBN PBS PBT PC PCD PCT PCTFE PE PEC PEG PEI PEK PEN PES PET PF PFA PI PIBI PMDI PMMA PMP PO PP PPA PPC PPO PPS PPSU Methyl cellulose Methylene diphenylene diisocyanate Methyl ethyl ketone peroxide Melamine formaldehyde Methyl methacrylate Polyethylene glycol monomethyl ether Melamine-phenol-formaldehyde Nitrile butyl rubber Naphthalene diisocyanate Natural rubber Oriented polyethylene terephthalate Oriented polypropylene Olefin-modified styrene-acrylonitrile Polyamide Poly(aryl ether-ketone) Poly(amide-imide) Polyacrylonitrile Polybutylene Poly(butadiene-acrylonitrile) Polybenzimidazole Polybutylene naphthalate Poly(butadiene-styrene) Poly(butylene terephthalate) Polycarbonate Polycarbodiimide Poly(cyclohexylene-dimethylene terephthalate) Polychlorotrifluoroethylene Polyethylene Chlorinated polyethylene Poly(ethylene glycol) Poly(ether-imide) Poly(ether-ketone) Polyethylene naphthalate Polyether sulfone Polyethylene terephthalate Phenol-formaldehyde copolymer Perfluoroalkoxy resin Polyimide Poly(isobutylene), Butyl rubber Polymeric methylene diphenylene diisocyanate Poly(methyl methacrylate) Poly(methylpentene) Polyolefins Polypropylene Polyphthalamide Chlorinated polypropylene Poly(phenylene oxide) Poly(phenylene sulfide) Poly(phenylene sulfone)... [Pg.959]

Different TPs have been used to modify thermosets, such as poly(ether sulfone) (PES), polysulfone (PSF), poly(ether ketone) (PEK), polyether imide (PEI), poly(phenylene oxide) (PPO), linear polyimides, polyhydan-toin, etc. (Stenzenberger et al., 1988 Pascal et al., 1990, 1995 Pascault and Williams, 2000). [Pg.414]

Jansen, J. C., Macchione, M., and Drioli, E. (2005), High flux asymmetric gas separation membranes of modified poly(ether ether ketone) prepared by the dry phase inversion technique, /. Membr. Sci., 255,167-180. [Pg.1127]

Five poly(arylene phthalide ketones) including 286 and 287 were used to modify electrodes for the voltammetric determination of nitroaromatic mixtures. This has potential applications in the area of explosives detection <2005MI508>. [Pg.606]

Other oiganic—inoiganic hybrids include poly(eth5ioxazoline)—silica, poly(vinyl alcohol)—silica, poly(arylene ether) ketone—silica, polyimide—silica, polyozoline—silica, poly(eth5iene oxide)—silica, and polymers—modified alkoxysilane. [Pg.260]

A slightly modified version of the same reaction allowed the synthesis of poly-functionalized a-diketones from linear enamino ketones (Scheme 8). [Pg.927]

The Tg-value of poly(ether ether ketone), PEEK is finally calculated as a second example of a Tg-value calculation according to the modified cohesion energy method ... [Pg.237]

Several modified phthalocyanine compounds have been found to effectively stabilise rubber/ Other unusual stabilisers include piperylene-methyl-styrene in poly(ethylene), dioxynaphthylpropane in polyfethylene), ketones and anilines for poly(3-butylthiophene), thioglycerol for wood pulp and dibutylphthalate for PMMA/ N-Arylphthalimides are self stabilising due to their donor-acceptor energy transfer properties/ ... [Pg.362]


See other pages where Poly ketone modified is mentioned: [Pg.12]    [Pg.185]    [Pg.2629]    [Pg.344]    [Pg.348]    [Pg.349]    [Pg.361]    [Pg.184]    [Pg.477]    [Pg.377]    [Pg.382]    [Pg.80]    [Pg.377]    [Pg.382]    [Pg.58]    [Pg.199]    [Pg.165]    [Pg.350]    [Pg.703]    [Pg.80]    [Pg.61]    [Pg.415]    [Pg.74]    [Pg.415]    [Pg.464]    [Pg.218]    [Pg.2629]    [Pg.115]   
See also in sourсe #XX -- [ Pg.118 , Pg.119 ]




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Poly ketone

Poly- modified

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