Polyamides polyethersulfon

Membranes UF membranes consist primarily of polymeric structures (polyethersulfone, regenerated cellulose, polysulfone, polyamide, polyacrylonitrile, or various fluoropolymers) formed by immersion casting on a web or as a composite on a MF membrane. Hydrophobic polymers are surface-modified to render them hydrophilic and thereby reduce fouling, reduce product losses, and increase flux [Cabasso in Vltrafiltration Membranes and Applications, Cooper (ed.). Plenum Press, New York, 1980]. Some inorganic UF membranes (alumina, glass, zirconia) are available but only find use in corrosive applications due to their high cost. 

High-performance GMTs are being developed with matrices such as polyethersulfone, polyetherimide, polyamide-imide, PPS, PEEK. 

Adhesion studies of epoxy resins modified with high modulus and high glass transition temperature thermoplastics have shown adhesion can reach or even exceed that of the unmodified resin. The use of flexible polyamides or flexible epoxides resulted in shear strength increases in epoxy systems employed by Cunliffe et al. [144],polyethersulfones [18,145],polyetherimides [109,146,147], and polyetherketones [148-150]. 

Membrane polymeric materials for separation applications are made of polyamide, polypropylene, polyvinylidene fluoride, polysulfone, polyethersulfone, cellulose acetate, cellulose diacetate, polystyrene resins cross-linked with divinylbenzene, and others (see Section 2.9) [59-61], The use of polyamide membrane filters is suggested for particle-removing filtration of water, aqueous solutions and solvents, as well as for the sterile filtration of liquids. The polysulfone and polyethersulfone membranes are widely applied in the biotechnological and pharmaceutical industries for the purification of enzymes and peptides. Cellulose acetate membrane filters are hydrophilic, and consequently, are suitable as a filtering membrane for aqueous and alcoholic media. 

Microfiltration units can be configured as plate and frame flat sheet equipment, hollow fiber bundles, or spiral wound modules. The membranes are typically made of synthetic polymers such as Polyethersulfone (PES), Polyamide, Polypropylene, or cellulosic mats. Alternate materials include ceramics, stainless steel, and carbon. Each of these come with its own set of advantages and disadvantages. For instance, ceramic membranes are often recommended for the filtration of larger particles such as cells because of the wider lumen of the channels. However, it has been shown that spiral wound units can also be used for this purpose, provided appropriate spacers are used. 

Most of the available commercial microporous membranes such as polysulfone, polyethersulfone, polyamide, cellulose, polyethylene, polypropylene, and polyvinylidene difluoride are prepared by phase inversion processes. The concept of phase inversion in membrane formation was introduced by Resting [75] and can be defined as follows a homogeneous polymer solution is transformed into a two-phase system in which a solidified polymer-rich phase forms the continuous membrane matrix and the polymer lean phase fills the pores. A detailed description of the phase inversion process is beyond the scope of this section as it was widely discussed in Chapters 1 and 2 nevertheless a short introduction of this process will be presented. 

Membrane materials for reverse osmosis and ultrafiltration applications range from polysulfone and polyethersulfone, to cellulose acetate and cellulose diacetate [12,18-23]. Commercially available polyamide composite membranes for desalination of seawater, for example, are available from a variety of companies in the United States, Europe, and Japan [24]. The specific choice of membrane material to use depends on the process (e.g., type of liquid to be treated and operating conditions) and economic factors (e.g., cost of replacement membranes and cost of cleaning chemicals). The exact chemical composition and physical morphology of the membranes may vary from manufacturer to manufaemrer. Since the liquids to be treated and... 

Most commercial UF and NF membranes and many MF membranes are made by the phase-inversion process, where a polymer is dissolved in an appropriate solvent along with appropriate pore-forming chemical agents. The polymer solution is cast into a film, either on a backing or freestanding, and then the film is immersed in a non-solvent solution that causes precipitation of the polymer. Such membranes are Polyamides, such as nylon, polyethersulfon (PESU), or... 

ID, internal diameter ED, external diameter CA, cellulose acetate CTA, cellulose triacetate PA, polyamide PAN, polyacrylonitrile PC, polycarbonate PE, polyethylene PES, polyethersulfone PP, polypropylene PS, polysulfone PVDF, polyvinylidene fluoride PVP, polyvinyl pyrrolidone RC, regenerated cellulose. 

Although some inorganic membranes are available, most UF membranes are made of polymers. The earliest UF membranes were made of cellulose acetate, but today, the most widely used polymers are polysul-fone and polyethersulfone, which are preferred because of their higher resistance to extremes of pH and temperature. Other polymers used include polyvinyl-idenefluoride, polyacrylonitrile, and polyamides. ... 

Precipitation has also been shown to occur on modified polymeric surfaces. An example of this includes Ca(II) containing hybrids of gelatin and 3-(glycidoxy-propyl)trimethoxysilane (Ren et al. 2001). Silanol groups on silicone (Oyane et al. 1999), poly (ethylene terephthalate), poly ether sulfone and polyethylene (Kokubo 1998), polymethylmethacrylate (PMMA), polyamide 6, and polyethersulfone (PESF) (Tanahashi et al. 1994) can also provide sites for apatite formation. 

High performance thermoplastics PEEK polyetherimides certain polyimides polyamide-imide polysulfone polyethersulfone... 

The engineering polymers that have already reached maturity consist of the Nylons (PA), polycarbonate (PC), acetal (POM), polyesters (PBT and PET) and Noryl (PPO). Their relative price is aroxmd 3. Including very novel polymers, a prestigious high priced group consists of the advanced engineering polymers (high performance) polysulfone (PSU), polyphenylene-sulfide (PPS), fluoroethylenes (PTFE and its derivatives), polyamide-imide (PAI), polyether-imide (PEI), polyethersulfone (PES), polyether-ether-ketone (PEEK), aromatic polyesters and polyamides, polyarylates and liquid-crystal-polymers (LCP). 

Polyamide-imide resin Polybutadiene Polychloroprene Polyether resin, chlorinated Polyethersulfone resin... 

Typical solvents used in membrane production include N-methylpyrrolidinone, N,N-dimethylacetamide, N,N-dimethylformamide, dimethylsulfoxide, tetrahydrofuran, dioxane, dichloromethane, methyl acetate, ethyl acetate, and chloroform. They are used alone or in mixtures. These are used most frequently as non-solvents methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, and t-butanol. Polymers involved include polysulfone, polyethersulfone, polyamide, polyimide, polyetherimide, polyolefins, polycarbonate, polyphenyleneoxide, poly(vinylidene fluoride), polyacrylonitrile, and cellulose and its derivatives. 

The most common type of microdialysis probe is constructed as a concentric tube as shown in Fig. 1. The probes usually consist of a semiper-meable membrane, such as polysulfone, polyethersulfone, polyamide, polycarbonate-poly ether copolymer, or cuprophan [4], glued between the tip of the inner cannula and the outer shaft, which are made of steel or plastic. The perfusion fluid (perfusate) enters the inlet flowing through the inner tube to its distal end and exits the inner tube to enter the space between the inner tube and the outer dialysis membrane where molecular exchange takes place. After the exchange, the fluid containing the molecules of interest (dialysate) is transferred towards the proximal end of the probe and is collected at the outlet for later... 

Polyetherimide (PEI), Polyamide-imide, Polyetheretherketone (PEEK), Polyaryl Sulfone, and Polyethersulfone (PES)... 

They are easily bonded with epoxy or urethane adhesives however, the temperature resistance of the adhesives do not match the temperature resistance of the plastic part. No special surface treatment is required other than abrasion and solvent cleaning. Polyetherimide (ULTEM ), polyamide-imide (TORLON ), and polyethersulfone can be solvent cemented, and ultrasonic welding is possible. 

This survey covers measurements on plastics with all the reinforcing agents previously mentioned and includes a wide range of plastics now being used in plastics technology. It includes commonly used plastics such as polyamides, polyesters, polyethylene terephthalate, and epoxy resins, but also covers newer plastics, such as polyimides, polysulfones, polyethersulfone, polyphenylene sulfide, and polyether ether ketone, all of which have more specialized applications. 

Volume resistivities are listed in Table 5.2. They range from as low as 2 ohm.cm for epoxy resins to as high as 16-18 ohm.cm for high-density polyethylene, polyether ether ketone, polystyrene, polymethylpentene, polyethylene terephthalate, polyarylates, polyphenylene oxide, polyamide imide, polyimides, polyurethane, polytetrafluoro-ethylene, perfluoroalkoxy ethylene, fluorinated ethylene-propylene copolymer, ultra-high-molecular-weight polyethylene, polysulfones, and polyethersulfones. 

During the last 40 years, ABS blends with most polymers have been patented. For example, wdth PVC in 1951, PC (introduced in 1958) in 1960, polyamide (PA-6) a year later [Grabowski, 1961a], polysulfone (PSF) in 1964, CPE in 1965, PET in 1968, polyarylether sulfone (PAES) and styrene-maleic anhydride (SMA) in 1969 (the blend is one of two resins called high heat ABS — the other being ABS in which at least a part of styrene was replaced with p-methylstyrene), polyethersulfone (PES) in 1970, polyarylates (PAr) in 1971, polyurethane in 1976, polyarylether (PPE or PAE) in 1982, with polyphenylene sulfide (PPS) in 1991, etc. 

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