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Poly sulfone polymers

Note that the ratio of the permeability coefficient of H2 and CO by the poly-sulfone polymer matrix is 4.019 x 10 Vl0.047xlO = 40 therefore, the selectivity of the composite membrane is close to that of the polysulfone polymer matrix. It should be also noted that two important assumptions were made in the above calculation. They are (1) the permeability coefficient of the void space was assumed to be the same as that of silicone rubber, and (2) the effective thickness of the void space was assumed to be the same as that of the polymer network. This implies that the void space was completely filled with silicone rubber, and its effective thickness is the same as that of the polymer network. Furthermore, we can calculate the loss in permeability by coating. The resistance without coating is that of the porous substrate, and therefore, it is designated as / ub- With respect to hydrogen gas, it becomes... [Pg.211]

Polydrill is a sulfonated polymer for filtration control in water-based drilling fluids [1775]. Tests demonstrated the product s thermal stability up to 200° C and its outstanding electrolyte tolerance. Polydrill can be used in NaCl-saturated drilling fluids as well as in muds containing 75,000 ppm of calcium or 100,000 ppm of magnesium. A combination of starch with Poly drill was used successfully in drilling several wells. The deepest hole was drilled with 11 to 22 kg/m of pregelatinized starch and 2.5 to 5.5 kg/m of Polydrill to a depth of 4800 m. Field experience with the calcium-tolerant starch/Polydrill system useful up to 145° C has been discussed in detail [1774]. [Pg.38]

Table 1. Common materials used in quenched-fluorescence oxygen sensing (Ru(dpp)3(C104)2 tris(diphenylphenantroline) ruthenium(II) perchlorate PtOEPK platinum(II)-octaethyl-porphine-ketone PtPFPP platinum(II)-tetrakis(pentafluorophenyl)porphine PS.poly(styrene), PSu poly(sulfone) PSB poly(styrene-butadiene) block co-polymer PVC polyvinylchloride) APET amorphous poly(ethyleneterephthalate) PE poly(ethylene). Table 1. Common materials used in quenched-fluorescence oxygen sensing (Ru(dpp)3(C104)2 tris(diphenylphenantroline) ruthenium(II) perchlorate PtOEPK platinum(II)-octaethyl-porphine-ketone PtPFPP platinum(II)-tetrakis(pentafluorophenyl)porphine PS.poly(styrene), PSu poly(sulfone) PSB poly(styrene-butadiene) block co-polymer PVC polyvinylchloride) APET amorphous poly(ethyleneterephthalate) PE poly(ethylene).
One of the first fictional fluoropolymers was poly-1,2,2-trifluorostyrene. On one hand, it has much better oxidation and chemical resistance in comparison with common hydrocarbon polymers and, on the other hand, a wide range of functional groups can be attached to the aromatic ring. A sulfonated polymer was successfully used as a membrane for fuel cells by General Electric Co.3... [Pg.92]

Schuster, M., Kreuer, K. D., Anderson, H. T. and Maier, J. 2007. Sulfonated poly(phenylene sulfone) polymers as hydrolytically and thermooxidatively stable proton conductors. Macromolecules 40 598-607. [Pg.180]

Sulfonated poly(4-substituted benzoyl-1,4-phenylene) homopolymers and copolymers using concentrated sulfuric acid or fuming sulfuric acid have been shown to form sulfonated polymers with variable degrees of sulfonation. To improve film formation of the sulfonated polyphenylenes, multiblock copolymers have been synthesized by reacting a more flexible poly(arylene ether sulfone) with sulfonated poly-phenylenes. ... [Pg.361]

Allcock s research led to the development of poly-phosphazene-based PEMs by his small molecule studies of the sulfonation of cyclic trimeric phosphazenes and the surface chemistry of polyphosphazene macromolecules. In a 1993 report, he described the sulfonation of aminophosphazenes with 1,3—propanesultone. While these specific materials are not necessarily ideal as PEMs, this study demonstrated a novel technique for creating sulfonated polyphosphazene materials that may provide more control over the sulfonated polymer product than wholesale sulfonation of a base polymer by a strong sulfonating agent. [Pg.365]

It has been also found that PhIO as an oxidant in the presence of a catalytic amount of sulfonated manganese and iron porphyrin supported on poly(vinylpyridinium) polymers in olefin epoxidation and alkane hydroxylation is a better oxidant than Bu4NHS05 °. Oxidation of adamantane to 1-adamantanol in good yield using BU4NHSO5 and acetone in the presence of aqueous NaHCOs was also reported . ... [Pg.1031]

For bioadhesive applications, anionic polymers appear to provide the most effective balance between adhesiveness and toxicity, with carboxylic materials preferred over sulfonic polymers [400]. Polyfacrylic acid) microparticles have been identified as particularly effective bioadhesive materials [402]. Studies with poly(acrylic acid) microparticles have indicated that, while water-swollen particles exhibit good bioadhesion, dry polymer particles give no adhesion at all. In addition, adhesive strength increases as the degree of ionization of the polymer is increased [402]. Thus the expanded nature of the polymer network is important to mucoadhesion, probably via polymer interdiffusion and entanglement with mucin [403],... [Pg.34]

Taking into account the above considerations, the SPs were suggested to be ideal microbicides for topical use [105]. A number of potential candidate microbicides have been shown to inhibit virus attachment, fusion, and entry into host target cells for sexually transmitted infections. These include cellulose sulfate, poly(styrene 4-sulfonate), polystyrene sulfonate, polymethylene-hydroquinone sulfonate, naphthalene sulfonate polymer, and a carrageenan derived from seaweed (Carraguard) that may prevent viral entry. Several candidate compounds have already progressed to various stages of clinical trials [106]. Currently, some of them have been formulated and are in phase II/III clinical trials. [Pg.277]

Sulfonation is very useful chemical modification of polymer, as it induces high polarity in the polymer changing its chemical as well as physical properties. Sulfonated polymers are also important precursors for ionomer formation [75]. There are reports of sulfonation of ethylene-propylene diene terpolymer (EPDM) [76, 77], polyarylene-ether-sulfone [78], polyaromatic ether ketone [79], polyether ether ketone (PEEK) [80], styrene-ethylene-butylene-styrene block copolymer, (SEBS) [81]. Poly [bis(3-methyl phenoxy) phosphozene] [82], Sulfonated polymers show a distinct peak at 1176 cm"1 due to stretching vibration of 0=S=0 in the -S03H group. Another peak appears at 881 cm 1 due to stretching vibration of S-OH bond. However, the position of different vibrational bands due to sulfonation depends on the nature of the cations as well as types of solvents [75, 76]. [Pg.147]

The single-ion conductor, PAGSOa Na (m/n = 0.4 or 1.0, in which m and n are the number of siloxy units in the structure), was made by consecutive hydrosilylation of PHMS with AM PEG and allyl glycidyl ether. The neutral polymer was sulfonated with aqueous NaHSOa, which quantitatively converted the epoxy group into -CH(0H)CH2S03". Excess NaHSOa was removed by repeated ultrafiltration of the polymer solution with a cutoff membrane having a Mw of 1000. The poly sulfonate was azeotropically dried with benzene and finally in vacuum at 50 °C for several days. [Pg.115]


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Poly polymers

Poly sulfonated

Poly sulfonated polymers

Poly sulfonation

Poly sulfone

Poly sulfones

Polymers sulfonation

Sulfone polymers

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