Poly sulfones physical

The maximum pore size used to separate phospholipid micelles, in which color pigments and other impurities are physically bound, can be in the range of 10,000-50,000 Da depending on the polymer type. Considerable swelling occurs with poly-sulfone membranes, which, in turn, affects the membrane chemistry drastically and reduces flow rates and in some cases totally closes the pores. Similar results have also been observed with polyamide and fluorinated polymers. 

Of the GRTP only ABS, polypropylene, poly-sulfone, and modified phenylene oxide are electroplated. Of these ABS represents about 85% of the market. Since the introduction of platable plastics, new formulations have been developed to give superior physical properties, platability, and appearance. For example, 25% glass-filled ABS has a shrinkage nearly equal to that of die-cast metals the increased stiffness reduces distortion during the plating operation and a reduction of 50% in the coefficient of linear thermal expansion permits it to pass the standard thermal cycling test of 82 to -40 C (190 to - 40 F) (Ref. 29). 

Poly(arylene ether ketone) and poly(arylene ether sulfone) were also tried to be incorporated into the hybrids with silica gel by means of the sol-gel procedure [19, 20], For example, triethoxysilyl-terminated organic polymer was subjected to co-hydrolysis with tetraethoxysilane. A systematic change in mechanical and physical properties of the hybrid glass has been found with the content of organic polymer and the annealing temperatures. 

Proton conductivity as a function of lEC for ETFE-g-PSSA = polyethylenetetrafluoroethylene-gra/t-polystyrene sulfonic acid, BAM membrane = substituted poly(trifluorostyrene) sulfonic acid, SPEEK = sulfonated poly(ether ether ketone) and Nafion. (From Peckham, T. J. et al. 2007. Journal of Materials Chemistry 17 3255-3268, and Dolye, M. et al. 2001. Journal of Physical Chemistry B 105 9387-9394.)... 

Kim, Y. S., Dong, L., Hickner, M. A., Glass, T. E., Webb, V. and McGrath, J. E. 2003. State of water in disulfonated poly(arylene ether sulfone) copolymers and a perfluorosulfonic acid copolymer (Nafion) and its effect on physical and electrochemical properties. Macromolecules 36 6281-6285. 

Wang, R, Li, J., Chen, T. and Xu, J. 1998. Sodium sulfonate-functionalized poly(ether ether ketone)s. Macromolecular Chemistry and Physics 199 1421-1426. 

Kim, J., Kim, B., Jung, B., Kang, Y. S., Ha, H. Y, Oh, I. H. and Ihn, K. J. 2002. Effect of casting solvent on morphology and physical properties of partially sulfonated polystyrene-block-poly(ethylene-ran-butylene)-block-polystyrene copolymers. Macromolecular Rapid Communication 23 753-756. 

In light of the discussion above, it is desirable to alter the chemical nature of these polymers to induce a measure of hydrophilicity while maintaining the excellent physical character. Sulfonation has been known to dramatically alter a number of characteristics of poljmeric materials (for example, dyeabllity (17), tensile strength (18), and, of particular interest to the present studies, hydrophilicity (19)). In fact, sulfonation has been used to improve the reverse osmosis performance of poly(phenylene oxide)... 

This specifity is dependent on the acidity of the catalyst, and was studied using the heterogeneous catalysts sulfonated and phosphonated poly benzene, and the homogeneous catalysts paratoluenesulfonic acid and phosphoric acid. The differences between the sulfonic and phosphonic acid groups were greater than the differences between heterogeneous and homogeneous phase, in spite of a considerable difference in reaction temperature. It was thus shown that for a typical Class A reaction, the type of acidity is more important than the physical state of the catalyst. These acidic catalysts were extremely active, and had to be partially neutralized in order to obtain reasonable rates ans selective reactions. 

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]. 

The ionic aggregates present in an ionomer act as physical crosslinks and drastically change the polymer properties. The blending of two ionomers enhances the compatibility via ion-ion interaction. The compatibilisation of polymer blends by specific ion-dipole and ion-ion interactions has recently received wide attention [93-96]. FT-IR spectroscopy is a powerful technique for investigating such specific interactions [97-99] in an ionic blend made from the acid form of sulfonated polystyrene and poly[(ethyl acrylate - CO (4, vinyl pyridine)]. Datta and co-workers [98] characterised blends of zinc oxide-neutralised maleated EPDM (m-EPDM) and zinc salt of an ethylene-methacrylic acid copolymer (Zn-EMA), wherein Zn-EMA content does not exceed 50% by weight. The blend behaves as an ionic thermoplastic elastomer (ITPE). Blends (Z0, Z5 and Z10) were prepared according to the following formulations [98] ... 

The problem with using surfactant-modified stationary phases in LC is that the surfactant will usually slowly elute (bleed) from the support thus resulting in different retention behavior of solutes with time. This is why most applications are in the area of GC or GLC. An exciting recent advance has been reported by Okahata, et al (181). Namely, a procedure has been developed for immobilizing a stable surfactant vesicle bilayer as the stationary phase in GC. A bilayer polyion complex composed of DODAB vesicles and sodium poly(styrene sulfonate) was deposited on Uniport HP and its properties as a GC stationary phase evaluated. Unlike previous lipid bilayers which exhibited poor physical stability, the DODAB polyion phase was stable. Additionally, the temperature-retention behavior of test solutes exhibited a phase transition inflection point. The work demonstrates that immobilized surfactant vesicle bilayer stationary phases can be employed in GC separations (181). Further work in this direction will likely lead to many such unique gas chromatographic supports and novel separations. 

The goal of the polymer industry is the design of a low-cost flame retardant polymer that does not require additives yet still has favorable physical and mechanical properties. New flame-resistant engineering plastics that have been commercialized are used in specialty applications. These include poly aryl sulfone and poly-etheretherketone (PEEK). These polymers work as heat-/flame-resistant polymers, but because of their... 

Biichi ef al. [28] reported a series of differently crosslinked FEP-g-polystyrene PEMs [FEP = poly(tctrafluorocthylcnc-co-hcxafluoropropylcnc), synthesized by preradiation grafting of the monomers onto a base film and subsequent sulfonation of the grafted component. Both, di vinyl benzene (DVB) and/or triallyl cyamirate (TAC) were used as crosslinkers. The physical properties ofthese membranes, such as water... 

In the previous section it was suggested that the parent polymer structure considerably influence the physical properties of the derived polysulfonates, imparting to them some of the mechanical and thermal properties of the precursors. This trend is particularly evident in the case of the perfluorinated hydrocarbon polymers. Polymers of this kind, such as e.g., poly(tetrafluoroethylene) (PTFE) are exceptional in their inertness to offensive environment, solvent resistance and high-temperature stability. These considerations led in the sixties to the development of unique sulfonic-acid derivatives of fluorocarbon copolymers by the DuPont Company. While several compositions were disclosed in the patent literature51, the preferred composition, which is the basis for the commercial Nafion ion-exchange membrane, is a copolymer of tetrafluoroethylene with a perfluorinated vinyl ether/sulfonyl fluoride52 ... 

Figure 17.24 Diffusion length of perfluorooctane sulfonate photoacid in partially protected poly(4-t-butyloxycarbonyloxystrene)-based resist at different temperatures, (x) 90°C, (A) 100°C, (-I-) IlOX, ( ) 120X, ( ) 130°C. The standard uncertainty in the ddev measurement is +10 A. (Adapted with permission from Ref. 45. 2001 American Institute of Physics.)...

Assistant Professor of Physical Chemistry, Helwan University, Cairo, Egypt Bisphenol-A polysulfone Polycarbonate Poly(ether sulfone)... 

C.C. de Araujo, K.D. Kreuer, M. Schuster, G. Portale, H. Mendil-Jakani, G. Gebel, J. Maier, Poly(p-phenylene sulfone) s with high ion exchange capacity lonomers with unique microstructural and transport features. Physical Chemistry Chemical Physics 2009, 11(17), 3305-3312. 

Hed Hedrick, J. L., Yilgor, I., Jurek, M., Hedrick. J. C., Wilkes, G. L., McGrath, J. E. Chemical modification of matrix resin networks with engineering thermoplastics 1. Synthesis, morphology, physical behaviour and toughening mechanisms of poly (arylene ether sulfone) modified epoxy networks. Polymer 32 (1991) 2020-2032. 

S.M.. Zaidi, S. D. Mikhailenko, S. Kaliaguine, Electrical properties of sulfonated poly ether ketone/polyether-imide blend membranes doped with inorganic acids. Journal of Polymer Science Part B Polymer Physics 38 (2000) 1386-1395. 

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