Solvents, mutual

Solution Deposition of Thin Films. Chemical methods of preparation may also be used for the fabrication of ceramic thin films (qv). MetaHo-organic precursors, notably metal alkoxides (see Alkoxides, metal) and metal carboxylates, are most frequently used for film preparation by sol-gel or metallo-organic decomposition (MOD) solution deposition processes (see Sol-GEL technology). These methods involve dissolution of the precursors in a mutual solvent control of solution characteristics such as viscosity and concentration, film deposition by spin-casting or dip-coating, and heat treatment to remove volatile organic species and induce crystaHhation of the as-deposited amorphous film into the desired stmcture. 

Parathion is very slightly soluble in water (20 parts per million), but is completely miscible in many organic solvents including esters, alcohols, ketones, ethers, aromatic and alkylated aromatic hydrocarbons, and animal and vegetable oils. It is practically insoluble in such paraffinic hydrocarbons as petroleum ether, kerosene, and refined spray oils (about 2%) unless a mutual solvent is used (1). 

Mutual solvents have been used to reduce surfactant adsorption on formation minerals, particularly oil-wetting surfactants (131). Ethylene glycol monobutyl ether is the most commonly used mutual solvent. 

Adsorption of corrosion inhibitors or cationic surfactants can reduce sandstone formation permeability. Alcohols can be used to remove corrosion inhibitors from rock surfaces. Oil-soluble corrosion inhibitors may be dissolved by organic solvents such as xylene or toluene containing a mutual solvent, most often ethylene glycol monobutyl ether, EGMBE (167). Aqueous fluids containing 5-10% EGMBE can be used to dissolve cationic surfactants. 

Hall, B.E. "Workover Fluids. Part I - Surfactants have differing chemical properties that should be understood to ensure proper application," World Oil(May 1986) 111-114 ibid "Part 2 - How the various types of surfactants are used to improve well productivity," World Oil(June 1986) 64-67 ibid "Part 3 - Use of alcohols and mutual solvents in oil and gas wells," World Oil(July 1986) 65-67 ibid "Part 4 - Use of Clays and fines stabilizers and treaters," World Oil(October 1986) 61-63 ibid "Part 5 - How certain chemicals react to stabilize clays and fines in the formation," World Oil(December 1986), 49,50. 

The sol-gel process involves hydrolysis of alkoxide precursors under acidic or basic conditions, followed by condensation and polycondensation of the hydroxylated units, which lead to the formation of porous gel. Typically a low molecular weight metal alkoxide precursor molecule such as tetramethoxy silane (TMOS) or tetra ethoxysilane (TEOS) is hydrolyzed first in the presence of water, acid catalyst, and mutual solvent... 

Harrod and Chalk (IId) observed that dichlorobisethylene-/x,/x -dichlo-roplatinum(II) isomerized 1-hexene in the presence of nucleophilic mutual solvents. Similar isomerizations were observed with all complexes of Pt(II), Pd(II), Rh(III), and Ir(III). No isomerization was observed with chloro and carboxylate complexes of Fe(lII), Co(II), Ni(II), and Ru(III). 

Uses Solvent for lacquers, varnishes, dopes, nitrocellulose, natural and synthetic resins in cleaning solutions, varnish removers, dye baths mutual solvent for formation of soluble oils lacquer thinners emulsion stabilizer anti-icing additive for aviation fuels. 

The absorption of disperse dyes by hydrophobic fibers such as polyesters is increased by the addition of dibenzothiophene 5,5-dioxide to the hot, aqueous dyebath. Presumably the sulfone behaves as a typical carrier acting as a mutual solvent for both fiber and dye. 

In this method the sample is reacted with a measured excess of aq KOH, using isopro-panol as a mutual solvent, if required (but not for EtAcet). The amt of KOH consumed, which is detd by titrating tbe excess with std mineral acid, is a measure of the ester originally present. Since this detn is based on acidimetric... 

Two methods have been utilized to circumvent the low solubility of organic compounds in water. The first is use of emulsifying ngem.--. such aa common household detergents, from which the product ran bo separated readily by steam-distillation sw.yot.iss The second is use of a suitable mutual solvent, e.g. acetone,1 fort-butanol,741-777 or dioxan.80- i . m>, 4ei, ess. iocs. i 7s. i4 e, ims, ms.m ... 

Ternary Critical Point. The point where, upon adding a mutual solvent to two partially miscible liquids (as adding alcohol to ether and water), the two solutions become consolute and one phase results. 

Canadian Industries Limited Explosive Composition Containing an Inorganic Oxidizer Salt, a Soluble Ligno-sulfonate, and Mutual Solvent Therefor... 

Amylamine Aminopentane Aminomethyl-butane,CSHU NH2. Several isomers are known, including Isoamylamine,(CH,)2 -CH-CHj-CHj-NHj. They can be prepd by the reaction of amyl chlorides with ammonia in the presence of alcohol as a mutual solvent. Datta Chatterjee(Ref 2) detd expln temps of amylaminepicrate and amylamineperchlo-rate and found them to be 270° and 262°, respectively... 

Because water and alkoxysilanes are immiscible, a mutual solvent such as alcohol is usually used as a homogenizing agent.12 However, gels can be prepared from... 

When dimethyldichlorosilane is hydrolyzed by stirring with water in a mutual solvent the proportion of volatile dimethylpolysiloxanes is increased, and it appears that hydrolysis in strong acids also increases the tendency toward the formation of lower cyclic forms. Hydrolysis in ammonium hydroxide solution decreases the proportion of volatile cyclic material.6 If insufficient water for complete hydrolysis is supplied, and particularly in a mutual solvent such as ether, there is formed a series of coifiplex dichlorosilanes of the type... 

Films of the three block copolymers were cast from chloroform, a mutual solvent for PS and PEO,( ) and the measured and 0. core level spectra are shown in Figure 2. The spectra show the characteristic peak of PEO, the shake-up satellite of PS, and an easily deconvoluted doublet for the core levels in PS and PEO. It is apparent from the spectra that he PS concentration at the copolymer surface increases as the PS in the copolymer increases. More importantly, however, an analysis of the spectral data clearly shows that the surface compositions are significantly richer in PS than would be predicted based on a knowledge of the bulk compositions of the block copolymers. In Figure 3 is shown a plot of the surface-vs-bulk compositions for the diblock copolymers. ... 

SPE can be prepared by dissolving the polymer and an alkali metal salt in a mutual solvent and then evaporating the solution on a teflon fluorocarbon resin plate in a dry atmosphere. SPE films are obtained by casting the solution and heating at relatively low temperatures ( 150°C) under vacuum. The existence of a polymer/salt complex, however, is no guarantee that the material will be a good ionic conductor. 

Many investigators have opted to study polymer compatibility in solution in mutual solvents, because of uncertainty as to whether a bulk mixture is actually in an equilibrium stale. Compatible components form a single, transparent phase in mutual solution, while incompatible polymers exhibit phase separation if the solution is not extremely dilute. 

The accounting of the quantum mechanical models for the mutual solvent-solute polarization in a self-consistent fashion is perhaps their greatest virtue. However, as already alluded to, the costs of ab initio formalisms may not be warranted—either because they cannot attain accuracies beyond the intrinsic limitations of the continuum solvation model or, alternatively, because they are simply not applicable to a prohibitively large system. In such instances, just as in the gas phase, semiempirical quantum mechanical models often provide an attractive alternative to the classical models discussed earlier. 

The hydrolysis of, for example, dimethyl dichlorosilane to cyclic dimethylsiloxanes and linear diols can be regarded as following a similar pattern, if OHs+Cl" is taken as the analogue of NH4+C1". Increase of acid concentration, or the use of a mutual solvent, increases the proportion of cyclic polymers their proportion is decreased by the use of insufficient, alkaline or scarce water in the foi-m of hydrated salts (see pp. 80 ff. in ref. 65). 

The many varieties of glyceryl monostearate are used as nonionic emulsifiers, stabilizers, emollients, and plasticizers in a variety of food, pharmaceutical, and cosmetic applications. It acts as an effective stabilizer, that is, as a mutual solvent for... 

An alternative route becoming increasingly popular with the wider commercial availability of a variety of alkoxides is to start with a metal alkoxide (M(OR)x, where R is an alkyl chain). The alkoxide is dissolved in alcohol (our laboratory normally uses propanol) to act as a mutual solvent for the alkoxide and the water which is then added dropwise at room temperature while stirring to initiate a hydrolysis reaction (Brinker and Scherer 1990). 

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