Polar solvents methyl ethyl ketone

SAN resins show considerable resistance to solvents and are insoluble in carbon tetrachloride, ethyl alcohol, gasoline, and hydrocarbon solvents. They are swelled by solvents such as ben2ene, ether, and toluene. Polar solvents such as acetone, chloroform, dioxane, methyl ethyl ketone, and pyridine will dissolve SAN (14). The interactions of various solvents and SAN copolymers containing up to 52% acrylonitrile have been studied along with their thermodynamic parameters, ie, the second virial coefficient, free-energy parameter, expansion factor, and intrinsic viscosity (15). 

Organic solutions of HOCl can be prepared in near quantitative yield (98—99%) by extraction of CU -containing aqueous solutions of HOCl with polar solvents such as ketones, nitriles, and esters (131). These organic solutions of HOCl have been used to prepare chlorohydrins (132) and are especially useful for preparation of water-insoluble chlorohydrins. Hypochlorous acid in methyl ethyl ketone has also been used to prepare Ca(OCl)2, by reaction with CaO or Ca(OH)2 (133), and hydrazine by reaction with NH3 (134). 

They show good to excellent resistance to highly aromatic solvents, polar solvents, water and salt solutions, aqueous acids, dilute alkaline solutions, oxidative environments, amines, and methyl alcohol. Care must be taken in choice of proper gum and compound. Hexafluoropropylene-containing polymers are not recommended for use in contact with ammonia, strong caustic (50% sodium hydroxide above 70°C), and certain polar solvents such as methyl ethyl ketone and low molecular weight esters. However, perfluoroelastomers can withstand these fluids. Propylene-containing fluorocarbon polymers can tolerate strong caustic. 

The slight extractability of TcO from perchlorate solutions and the almost non-extractability by non-polar solvents in used for the re-extraction of technetium into the aqueous phase by either shaking the organic phase with perchlorate solution or by diluting the extractant with a non-polar solvent. As shown in , after 3-4 fold dilution of methyl ethyl ketone by hexane, the distribution coefficient in the system organic solvent/water is only about 6x 10 . 

Thin-layer chromatography on alumina,271 silica gel,139,271>272 cellulose,262,272 Avicel,250,262 and polyamide273 thin layers has extended considerably the applications of chromatography to the separation and purification of imidazoles. Polyamide layers are useful especially for the separation of imidazoles and their 1-methyl derivatives and (using methyl ethyl ketone as solvent) allows separation of the more polar co mpounds su ch as 1,3 -dimethylimidazolium iodide.2 7 3 Imidazolines have also been separated by thin-layer chromatography.274... 

An unidentiffed compound, not polonium hydroxide and presumed to be P0OCI2, was obtained by the evaporation of a dilute hydrochloride acid containing polonium. The residue is soluble in polar organic solvents such as ethanol, ethylene glycol, dioxane, acetone, and methyl ethyl ketone. It is insolnble in benzene or chloroform. 

Landfills have been the most popular depositories of spent nickel catalyst. Environmental concerns regarding the impact of nickel and conservation elforts to preserve nickel supplies have stimulated recycling and reclamation of the nickel component. Solvent extraction of organic material from the nickel is most effective with polar solvents such as isopropanol and methyl ethyl ketone (108). 

Dieterich et al. (1A6) and Taft and Mohar (157) have prepared excellent reviews of urethane ionomers. One of the most Important characteristics of urethane ionomers is the ease with which they form stable water dispersions without the use of emulsifiers (158-16A). These dispersions consist of colloidal two-phase systems that can be readily prepared by adding a solution of the urethane ionomer in polar solvents, such as methyl ethyl ketone or tetrahydrofuran,... 

The mobile phase competes with the sample components for adsorption sites on the stationary phase and thereby decreases the number of adsorption sites which are available for the solutes (i.e. sample components). Consequently, use of increasingly polar mobile phases decreases the retention times of solutes. Several solvents used in LSC in order of increasing polarity are Fluoroalkanes, petroleum ether, carbon tetrachloride, cyclohexane, toluene, benzene, esters, chloroform, ethyl ether, dichloroethane, methyl ethyl ketone, acetonitrile, alcohols, water, pyridine, organic acids. 

The migration properties of free pertechnetate may be influenced by the choice of different mobile and stationary phases. When silica gel or paper is used as stationary phase, the migration of free pertechnetate depends on the solubility of this anion in the solvent. In a polar solvent like saline, 80% methanol, acetone or 2-butanone (methyl ethyl ketone, or MEK) pertechnetate migrates with the SF (k =0.6-1.0). If a nonpolar, lipophilic solvent (e.g., ethylacetate, chloroform) is used and the sample is dried (no water content), free pertechnetate remains at the origin. In addition, when using an anion-exchange material in for stationary phase (e.g., aluminum oxide), free pertechnetate will be retained at the start. 

The reaction of peroxy radicals with ketone is that between two dipolar particles in a polar medium. The role of the medium in methyl ethyl ketone oxidation has been studied in detail [152—157]. The rate coefficient, ftp, decreases with dilution of methyl ethyl ketone by a non-polar solvent (benzene, n-decane, etc.). The change of fep is caused by the nonspecific solvation of reacting particles and activated complexes. The relationship between ftp and the dielectric constant, e, is expressed by the Kirkwood equation... 

Polar solvents inhibit the reaction, presumably by interfering with the adsorption process as noted in the mechanism proposed for manganese dioxide oxidations. Oxidation of 1-heptanol to heptanal with Fetizon s reagent was quantitative when the solvent was 35% hexanes. When benzene was used as a solvent, the yield of heptanal dropped to 90% and was < 1% in ethyl acetate, methyl ethyl ketone, or acetonitrile. 69 Since the oxidation is a heterogeneous reaction, requiring adsorption of the alcohol substrate, as the surface area of the reagent increases (increased by precipitation on Celite), the rate of oxidation increases. An optimum ratio is reached beyond which increasing the silver carbonate/Celite ratio slows the oxidation. 69... 

Solubility tests permit at least a tentative identification of the components also in polymer blends. Blends of ABS and polycarbonate are soluble in most polar solvents. Solubility in tetrahydrofuran and methyl ethyl ketone demonstrates the absence of polyolefins in such blends and the presence of aromatic polyesters or of polyamides can also be excluded. On the other hand, generally they may contain such highly soluble polymers as polystyrene, PVC, ABS, or polymethacrylates. However, blends that contain polybutylene terephthalate or polyethylene terephthalate do not dissolve in the usual solvents, but require m-cresol, which can he a clear indication that aromatic polyesters are present. Polyolefins dissolve at high temperatures, at least 110 °C, in toluene and p-xylene, and this behavior is characteristic of blends that contain polyethylene or polypropylene. 

Methyl isobutyl ketone, methyl ethyl ketone, acetone, dimethylformamide, tetrahydrofuran, l-methyl-2-pyrrolidine, acetonitrile and related polar solvents Freon and freon ether type solvents are best for the more heavily (8) fluorinated polymers... 

Nonpolar polymers (polyisoprene, polybutadiene) mix infinitely with alkanes (hexane, oetane, ete.) but do not mix with sueh polar liquids as water and aleohols. Polar polymers (eellulose, polyvinylalcohol, ete.) do not mix with alkanes and readily swell in water. Polymers of the average polarity dissolve only in liquids of average polarity. For example, polystyrene is not dissolved or swollen in water and alkanes but it is dissolved in aromatie hydrocarbons (toluene, benzene, xylene), methyl ethyl ketone and some ethers. Polymethylmethacrylate is not dissolved nor swollen in water nor in alkanes but it is dissolved in dichloroethane. Polychloroprene does not dissolve in water, restrictedly swells in gasoline and dissolves in 1,2-dichloroethane and benzene. Solubility of polyvinylchloride was considered in terms of relationship between the size of a solvent molecule and the distance between polar groups in polymer. ... 

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