Polyether sulfones production

The polyether sulfones are amorphous and have high glass transition temperatures of between 190 and 290° C. They have good creep behavior, dielectric properties, and thermal and hydrolytic resistance. They are suitable for use in engineering parts, electrical components, as pan and saucepan coatings, and also for the removal of salt from seawater when used in membrane form as sulfonated products. 

Table 6.5 Identification of the products in the flash Py-GC-MS of polyether sulfone (PES) ...

Poly(aryl sulfone) n Also called Polyether-Sulfone. An aromatic polymer consisting of benzene rings linked by both sulfone (—SO2—) groups and ether oxygen atoms. Poly (aryl sulfones) can be synthesized by solution polymerization in a polar solvent. Several commercial products of this type have been developed as reasonably high temperature resistant engineering plastics. 

Hollow fiber membranes are generally solvent spun and as such can be considered a sub-group of solvent spinning. Major polymers used in these processes are polysulfone, Polyvinylidene diflouride(PVDF) and polyether-sulfone. The major applications are hemodialysis, water purification, and air separation. This is a huge business that has been growing at over 10% per annum for many years. Although the product usage in annual tons is very small, the end-use revenue is in billions (Anon., 2011). 

Production and Uses of Aliphatic Compounds. 11. Ether, Epoxide and Polyether, Carboxylic Acids and Their Derivatives, Sulfonic Acids, Toxicological Data of Aliphatic Fluorine Compounds ... 

Synthesis of (+)-Eurylene. The reaction of a-sulfonyl anions with carboxylic acid derivatives is used as the key step in the construction of various natural products. The resulting (3-oxo sulfone intermediate is then further elaborated and/or desulfonylated to afford the desired product. A variety of carboxylic acid derivatives has been used, esters being most often employed, as depicted in Eq. 149 for the synthesis of the triterpene polyether (+)-eurylene.149... 

In technical-scale production, it is mainly the carboxylates, sulfates, sulfonates and phosphates which act as the hydrophilic parts of surface-active molecules. In addition to soap, the carboxylic group also plays this role in polyether carboxylates, sarcosinates and asparaginates. 

Surface-Active Materials. The active defoamer components are necessarily surface active materials, but this ancillary category covers the surfactants that are often incorporated in the formulation for other effects such as emulsification or to enhance dispersion. Emulsifiers are essential in the common oil-in-water emulsion systems, but they are also required where mixtures of active liquid components are used. For example, specialized oil-in-oil emulsifiers are needed in defoamers based on silicone/polyether mixtures, oil-in-water emulsifiers are incorporated in some defoamers even when the final product contains no water. This is to promote emulsification (self-emulsifiable) or dispersion into aqueous foaming systems. These additives increase the speed of foam decay by promoting rapid dispersion of the defoamer throughout the foaming media. Examples of emulsifying agents used in defoamer compositions are fatty acid esters and metallic soaps of fatty acids fatty alcohols and sulfonates, sulfates, and sulfosuccinates sorbi-tan esters ethoxylated products such as ethoxylated octyl or nonylphenols and silicone-polyether copolymers. 

Polymeric Viologen Systems. The write-erase efficiency of an ECD using for example aqueous MV would be low since both the dicationic and radical-cation states are very soluble. Improved MV-based systems may be made by retarding the rate at which the radical-cation product of electron transfer diffuses away from the electrode by use of an anionic polyelectrolyte such as poly(2-acrylamido-2-methylpropane-sulfonic acid) (polyAMPS) (46,47) or the sulfonated perfluorinated polyether, Nafion (48). An alternative approach is the surface modification of an electrode using silanization methodology (49), a preformed polymeric viologen salt (50) or oxidative electropolymerization of a pyrrole-substituted viologen (51) (Fig. 5). 

Figure 3.9 Reaction of polyethers with p-toluene sulfonic acid - gas chromatography. Gas chromatogram of reaction products of polyurethane polyethers (1) propylene glycol diacetate (2) glycerol triacetate (3) trimethylpropane triacetate (4) triethylanolamine triacetate (5) pentaerythritol tetracetate. Gas chromatographic conditions column 1 m x 3 mm, coated with 15% FFAQ on Uniport B, oven 170 °C chart speed 1 cm/s. (b) Gas chromatogram of reaction products of polyurethane polyethers based on amines (1) pyropylene glycol diacetate (2) derivative from 1,2 diaminoethane (3) derivative from 2,2 -diaminodiethylamine. Gas chromatographic conditions Column 1 m x 3 mm packed with 15% SE-30 on Uniport B oven 230 "C chart speed, 1 cm/min.

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