Polysulfone film

Figure 12.9 Pressure change observed in a chamber containing a substrate pseudo-saturated to an initial pressure of 200 mm Hg of 4-vinylpyridine during glow discharge Key Q, Millipore filter , glass slide A, porous polysulfone film.

The pressure increase in a reaction chamber that contains a porous substrate when a monomer vapor is introduced by a given flow rate can be utilized to calculate the sorption capability of the porous substrate. The pressure buildup curves are shown in Figure 34.6 for Millipore filter and porous polysulfone film. The pressure buildup curve with a porous glass tube is too slow to be presented in the same time scale. From the slope of the linear portion of the pressure buildup curve, the ratio of monomer sorbed/monomer fed into the system is estimated as 0.636 for the polysulfone film, 0.926 for Millipore filter, and 0.9987 for the porous glass tube. 

Figure 34.7 Change of pressure in a chamber which contains a substrate in glow discharge (under vacuum) (O) Millipore filter ( ) glass slide (A) porous polysulfone film.

Figure 34.13 Reverse osmosis characteristics of composite membranes prepared by plasma polymerization of benzene/H20/N2 compared with those from acetylene/H20/ N2 represented by the solid line porous polysulfone film as the substrate, 3.5% NaCl at 1500 psi.

Figure 34.17 Change of salt rejection (SR) and water flux with time (3.5% NaCl, 1500 psi) membrane of plasma-polymerized 4-vinylpyridine on porous polysulfone film.

Koehler, J.A., Ulbricht, M., and Belfort, G., Intermolecular forces between a protein and a hydrophilic modified polysulfone film with... 

The initial microporous support films used in the work were made from cellulose acetate by a modification of the Loeb-Sourirajan procedure. Later work showed that several types of the membrane filters manufactured by Millipore Corporation and Gelman Sciences, Inc., performed as well and allowed higher flux. A continued search for a more compression-resistant support film led to the development of polycarbonate, polyphenylene oxide and polysulfone microporous films in 1966 to 1967 (8). Of these, microporous polysulfone film proved to have the best properties. The polysulfone support was made by casting a liquid layer of a 12.5 to 15 percent solution of Union Carbide Udel P35OO polysulfone in dimethylformamide onto a glass plate at 4 to 7 mils (100-175 pm) thickness, then coagulating the film in water. 

In addition to the usual vinyl monomers, most organic compounds having adequate vapor pressure could be used to deposit a barrier layer on porous supports. Additional copolymers could be formed by inclusion of nitrogen in the reactant gases. The supports used included Millipore filters, porous polysulfone films and porous glass tubes. Examples were presented of plasma formed membranes with 99 percent salt rejection, 38 gfd flux (63.3 L/sq m/hr) and low flux decline in seawater tests. A recent report by Heffernan et al describes gas phase deposition of membranes on hollow fibers (30). 

The NS-100 membrane is capable of giving salt rejections in excess of 99% in tests on salt solutions simulating seawater (18 gfd, 3.5% synthetic seawater, 1,500 psi, 25°C). If the polyurea interfacial reaction step is omitted, and the polyethylenimine-coated polysulfone film is heat-cured as usual, a crosslinked polyethylenimine semipermeable barrier film is generated. This membrane gives 70% salt rejection and 55 gfd water flux under the same test conditions as above. Also, if the fully formed NS-100 membrane is dried at 75°C, which is too low a temperature to effectively crosslink the amine layer, the resulting film will exhibit a salt rejection of 96% or less. 

P. Zschocke and D. Quellmatz, Novel ion exchange membranes based on aromatic polysulfone, J. Membr. Sci., 1985, 22, 325 W.H. Daly, Modification of condensation polymers, J. Macromol. Sci., Chem., 1985, A22, 713-728 N. Sivashinsky and G.B. Tanny, Ionic heterogeneities in sulfonated polysulfone films, J. Appl. Polym. Sci., 1983, 28, 3235-3245 M.D. Guiver, G.P. Robertson, M. Yashikawa and C.M. Tam, Funtionalized polysulfone Methods for chemical modification and membrane applications, Membrane Formation and Modification, ACS Symposium Series, ed. I. Pinnau and B.D. Freeman, American Chemical Society, Washington DC, 2000, Vol. 744. 

J. Ceynowa, Electron microscopy investigation of ion exchange membranes, Polym., 1978, 19, 73-76 N. Sivashinsky and G.B. Tanny, Ionic heterogeneities in sulfonated polysulfone films, J. Appl. Polym. Sci., 1983, 28, 3235-3245. 

The dissolution behavior of P(la-aft-S02) was studied on QCM in a 0.21 N TMAH solution using thin films cast from ethyl lactate and baked at 130 °C for 60 sec. Figure 4 presents the dissolution kinetics curve of the polysulfone film. The 450-nm-thick film dissolved away in 0.15 sec, with an extremely fast dissolution rate of 30,000 A/sec, which was nicely observed by our QCM setup. The dissolution rate of poly(4-hydroxystyrene) (PHOST) in the same 0.21 N developer is in the range of 3000-200 A/sec depending on its molecular weight (27). Thus, the fiuoroalcohol polymer dissolves at least one order of magnitudes faster than PHOST, which was unexpected considering the similar pKa values of the fiuoroalcohol and phenol. In... 

Yun N G, Won Y G and Kim S C (2004) Toughening of carbon fiber/epoxy composite by inserting polysulfone film to form morphology spectrum, Polymer 45 6953-6958. 

Circuit card edge connectors and carrier for I.C. flat packs Polysulfone film... 

Fluorized carbon polymer films have been applied as a low-loss substrate material for flexible circuits. However, they do not have good dimensional stability or adhesion characteristics. High cost of the materials is the major reason that they cannot be standard in flexible circuits. In the last 20 years, several heat-resistant films, such as polypalabaUc acid film and polysulfon film, have been developed as alternative substrate materials in flexible circuits instead of polyimide films. Unfortunately, there was no successful material from a business standpoint. LCP films and PEEK have been considered as the new materials of high-speed flexible circuits based on the low dielectric constant and loss tangents. 

Chlorine-resistant aromatic polyamide-based reverse-osmosis films are manufactured by treatment of polysulfone film supports with a solution of chlorosulfonic acid in acetic anhydride for 2-10 hours, followed by soaking the film in polyamide and poly (acid chloride) solutions, and finally baking at 100... 

Bautista-Quijano J, Aviles F, Aguilar J, Tapia A (2010) Strain sensing capabilities of a piezoresistive MWCNT-polysulfone film. Sens Actuators, A 159 135... 

Vaisanen, R, and Nystrom, M. (1997). Comparison of polysulfone membranes and polysulfone films. Acta Polytech. Scand., Ch. 247, pp. 25-34. 

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