Ester Solvents Research Articles

Solvation in weak complexing n-octyl phthalate and n-octyl tetrachlorophthalate solvents by gas chromatography

Abstract The solution properties of a varied group of solutes in di- n -octyl phthalate and di- n -octyl tetrachlorophthalate over the temperature range 60 to 120 °C were studied by gas chromatography. The solvation parameter model was used to assign the contribution of individual intermolecular interactions to the gas-liquid partition coefficients. The dominant interaction was dispersion with only small contributions from dipole-type interactions, n - and π -electron donor/acceptor interactions (for the tetrachlorophthalate ester only), and solvent hydrogen-bond base interactions. Neither phthalate ester exhibited solvent hydrogen-bond acid properties. Complexes formed between solutes and these phthalate ester solvents are likely to be of the Van der Waals type, perhaps augmented by dipole-type interactions and hydrogen-bond complexation with hydrogen-bond acid solutes. In addition, n - and π -electron complexation interactions, in the temperature range studied, may contribute to complex formation with the tetrachlorophthalate ester, but are too weak to be the dominant interactions involved. In general, the range of Chromatographic selectivity obtainable through exploitation of the phthalate and tetrachlorophthalate nucleus does not warrant their selection as building blocks for new polymer-supported phases with the expectation of providing opportunities to extend the selectivity range of existing gas Chromatographiec stationary phases. In addition, the influence of interfacial adsorption as a retention mechanism for the determination of solvent properties and as a potential source of disagreement between reported solvent properties for the phthalate esters is discussed.

Water-Enhanced Solvation of Organic Solutes in Ketone and Ester Solvents

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTWater-Enhanced Solvation of Organic Solutes in Ketone and Ester SolventsJane H. Lee, Vincent Van Brunt, and C. Judson KingCite this: Ind. Eng. Chem. Res. 1994, 33, 5, 1373–1379Publication Date (Print):May 1, 1994Publication History Published online1 May 2002Published inissue 1 May 1994https://doi.org/10.1021/ie00029a037RIGHTS & PERMISSIONSArticle Views139Altmetric-Citations5LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (770 KB) Get e-Alerts Get e-Alerts

In vitro hydrolysis of methyl acetate, a limitation in application of head-space gaschromatography in biological monitoring of exposure

Stoichiometric conversion of methyl acetate to methanol in vitro was detected when methyl acetate was incubated with blood for 2 to 8 h. The velocity of the reaction was so fast that almost all of methyl acetate disappeared in 8 h. The methanol formation was further confirmed by means of gaschromatography-mass spectrometry. The capacity to hydrolyze methyl acetate was evenly distributed in cellular and noncellular fractions of blood, but not in urine. The significance of the observation is discussed in relation to biological monitoring of exposure to industrial ester solvents by means of head-space gaschromatography of blood samples.

In vitro cholesterol gallstone dissolution: comparison of methyl tert-butyl ether with three new ester solvents.

The in vitro effectiveness of three new cholesterol gallstone solvents that have a potential for clinical use--ethyl propionate, isopropyl acetate, and n-propyl acetate--was compared with that of the well-known cholesterol solvent methyl tert-butyl ether (MTBE). Ten sets of matched gallstones were initially weighed, imaged with radiography and computed tomography (CT), and analyzed for content. One stone from each set was incubated in one of the four solvents at 37 degrees C. Solvents were changed at 30-minute intervals. The study was stopped either when the stones were completely dissolved or at the end of 7 hours. Any residual fragments were weighed, reimaged, and reanalyzed for content. There were no statistical differences between dissolution times of the stones in MTBE compared with those in the three new solvents. Ethyl propionate and n-propyl acetate appear to be as efficacious as MTBE in dissolving cholesterol stones and could be attractive alternatives for gallstone chemolysis.

Review of glycol ether and glycol ether ester solvents used in the coating industry.

Ethylene oxide-based glycol ether and glycol ether ester solvents have been used in the coatings industry for the past fifty years. Because of their excellent performance properties (evaporation rate, blush resistance, flow-out and leveling properties, solubility for coating resins, solvent activity, mild odor, good coupling ability, good solvent release) a complete line of ethylene oxide-based solvents of various molecular weights has been developed. These glycol ether and glycol ether ester solvents have better solvent activity for coating resin than ester or ketone solvents in their evaporation rate range. The gloss, flow and leveling, and general performance properties of many coating systems are dependent on the use of these products in the coating formula. Because of the concern about the toxicity of certain ethylene oxide-based solvents, other products are being evaluated as replacements in coating formulas.

Review of Glycol Ether and Glycol Ether Ester Solvents Used in the Coating Industry

Ethylene oxide-based glycol ether and glycol ether ester solvents have been used in the coatings industry for the past fifty years. Because of their excellent performance properties (evaporation rate, blush resistance, flow-out and leveling properties, solubility for coating resins, solvent activity, mild odor, good coupling ability, good solvent release) a complete line of ethylene oxide-based solvents of various molecular weights has been developed. These glycol ether and glycol ether ester solvents have better solvent activity for coating resin than ester or ketone solvents in their evaporation rate range. The gloss, flow and leveling, and general performance properties of many coating systems are dependent on the use of these products in the coating formula. Because of the concern about the toxicity of certain ethylene oxide-based solvents, other products are being evaluated as replacements in coating formulas.

Photolysis of arene chromium tricarbonyls and photoinitiation of polymerization. Part 2.—Toluene, anisole, fluorobenzene and chlorobenzene chromium tricarbonyls

The photolysis of some arene chromium tricarbonyls, arCr(CO)3, has been studied in cyclohexane, methyl methacrylate and ethyl acetate solutions. Spectral changes occurring on irradiation are generally similar to those described for benzene chromium tricarbonyl under comparable conditions. In the ester solvents they suggest the formation of species such as arCr(CO)2S and Cr(CO)5S, where S represents the ester and coordination to the metal occurs through the carbonyl group. When carbon tetrachloride is present development of these spectral features is eliminated or reduced, on account of reaction between the above species and CCl4.As with benzene chromium tricarbonyl, the rate of arene generation is much greater in methyl methacrylate solution than in hydrocarbon media and it is further increased by the presence of CCl4.Systems containing arCr(CO)3 and CCl4 are active photoinitiators of free-radical polymerization. The primary radicals generated have been shown by spin-trapping to be trichloromethyl. At ‘high’[CCl4](ca. 0.1 mol dm–3) the quantum yields of photodecomposition of the carbonyl and photoinitiation are equal for all the derivatives studied, one ar—Cr bond being broken for each Ċl3 formed. The order of quantum yields for the various arene derivatives is fluorobenzene > chlorobenzene > benzene > toluene anisole, probably the same as the order of the ar—Cr bond dissociation energies.A reaction scheme similar to that proposed for the benzene derivative and involving exciplex formation between excited arCr(CO)3 and methyl methacrylate is consistent with all the experimental data.

Thermodegradation of polyvinyl chloride in presence of 2,2′ -DI-1,6,7-Trihydroxyl-3-methyl-5-isopropyl-8-aldehydonaphythl

The authors consider the kinetic patterns of the thermo-oxidative and thermal degradation of PVC in the solid phase and in a medium of complex esters in presence of a natural compound of the phenol type 2,2′-di-1,6,7-trihydroxy-3-methyl-5-isoprophyl-8-aldehydonaphthyl (gossypol). It has been established that gossypol effectively inhibits the thermo-oxidative dehydrochlorination of PVC in the liquid and solid phases. The stabilizing activity of gossypol is due both to the prevention of the oxidative degradation of PVC and the complex ester solvents of the polymer, the natural dinaphthyl compound having in this respect a number of specific advantages over the widely used synthetic anti-oxidants of the phenol type.

Extraction of europium with thenoyltrifluoroacetone into alcohol, ketone and ester solvents

Effect of solvent has been studied on the extraction of tris-thenoyltrifluoroacetone (TTA) chelate of europium(III). Donor-active solvents (S) greatly promote the extraction owing to the formation of solvate species EuA 3· mS ( m = 1, 2). Linear relations were established between the distribution ratios of europium ( D Eu) and the partition constants of TTA ( P HA); log D Eu (at a definite pA) = a log P HA + b , where constants a and b were empirically determined for each series of solvents. The regularity is interpreted in terms of dual roles of solvent as donor and as medium.

Extraction of uranyl 2-thenoyltrifluoroacetone complexes into alcohol, ketone, ether and ester solvents

The extraction of the 2-thenoyltrifluoroacetone (TTA) complex of uranyl ion into four types of solvents containing donor solvents has been investigated. The species extracted was found to be UO2A2 · S (S=alcohol, ketone, ether and ester). The extraction was much enhanced with donor solvents. The distribution ratios (DM) were estimated by means of the equations, log DM = a log PHA + b, and log DM = log DZn + c (where a, b and c is constant). The estimated values were in good agreement with the observed values in a number of oxygen-containing solvents. The regularities in extraction are discussed in terms of the two main roles of donor solvents, as medium and as coordinating reagent. On examine les possibilités d'extraction du complexe thénoyltrifluoroacétone-2 (TTA)-uranyle, dans quatre types de solvants, contenant des solvants donneurs. Les substances extraites sont du type UO2A2 · S (S = alcool, cétone, éther et ester). Les coefficients de partage (DM) ont été calculés à l'aide des équations, log DM = a log PHA + b et log DM = log DZn + c (où, b et c sont constants). Die Extraktion des Komplexes zwischen Uranylion und 2-Thenoyltrifluoraceton (TTA) durch vier Arten von Lösungsmitteln, die Donator-Lösungsmittel enthielten, wurde untersucht. Die extrahierten Spezies hatten die Zusammensetzung UO2A2 · S (S = Alkohol, Keton, Äther und Ester). Die Extraktion wurde durch Donator-Lösungsmittel stark erhöht. Die Verteilungsverhältnisse (DM) wurden ermittelt mit Hilfe der Gleichungen log DM = a log PHA + b und log DM = log DZn + c (wobei a, b und c konstant sind). Die so erhaltenen Werte stimmten bei einer Anzahl von sauerstoffhaltigen Lösungsmitteln mit den beobachteten Werten gut überein. Die Regelmässigkeiten bei der Extraktion werden diskutiert im Zusammenhang mit den beiden Hauptfunktionen der Donator-Lösungsmittel, die als Medium und als koordinierendes Reagenz wirken.

GLC Study of Solvent Effects in Complexing Reactions in Non-Aqueous Media

Formation constants (K1) for alkyl benzene complexes with 2,4,7-trinitro-9-fluorenone at infinite dilution at 60°C, in each of six alkyl ester solvents and in β,β′-thiodipropionitrile, have been measured. It is shown that no simple relationship between formation constants and infinite dilution activity coefficient (γf∞) of the alkyl benzenes in the solvents exists. However, for the ester solutions, it is shown that log K1 is linearly related with the thermal contribution to γf∞, i.e., γt∞. The analytical uses of π-complexing substances are discussed and a general equation developed. Broad criteria which help to narrow the field of choice of π-complexing additives are outlined.

Some physical properties associated with the urethane group—I.: N-ethyl urethane

The enthalpy of hydrogen bond formation in N-ethyl urethane is estimated from i.r. and NMR data as about -2kcal.mole t̄1. From a comparison of the dielectric relaxation properties in the ultra high frequency region with the viscous flow and spectral properties of the N-ethyl urethane, it is concluded that in non-polar solvents dielectric orientation polarization involves the fracture and reformation of long hydrogen-bonded chains of N-ethyl urethane molecules. The activation energies for dielectric relaxation and for viscous flow in undiluted N-ethyl urethane are both 6·5 kcal.mole t̄1. In ethereal or ester solvents N-ethyl urethane hydrogen-bonds to the solvent and the activation energies for flow and dielectric reorientation processes are reduced; it is suggested that urethane solvent interactions are most important in determining flow or dielectric orientation processes. Dipole moments and NMR chemical shifts for N-ethyl urethanes are also reported.

Regularities in the distribution of TTA and its scandium chelate into a series of ester solvents

The distribution ratios of TTA and its scandium chelate between aqueous perchlorate solutions (μ=0.1) and 15 ester solvents including ethyl acetate were determined at 25°. A good correlation was found between the distribution coefficients of TTA and the “solubility parameter” of the ester solvents. The relationship between the distribution coefficients of the scandium chelate ( P M) and those of TTA ( P HA) was shown to be, log P M= n log P HA+ const. The distribution of this chelate into another ester can thus be predicted.

Cohesive energy density of high polymers. Part V. C. E. D. of polymethacrylates

AbstractThe C.E.D.'s of methyl, ethyl, butyl, and isobutyl methacrylates have been estimated from their solution viscosity measurements in a number of alkyl ester solvents,4,5. The solubility parameters obtained, (9.40, 9.15, 9.00, and 8.65) for the above polymers, suggest that C.E.D.'s of polymethacrylates are less than those of polyacrylates and in the homologous series, the C.E.D. decreases with increases in the length of the alcoholic chain.

Heats of mixing of polymers with ester and ether solvents

AbstractHeats of mixing at infinite dilution have been obtained for polydimethylsiloxane in four series of ester solvents: the methyl and ethyl esters of the aliphatic acids, and the acetic and propionic esters derived from the normal alcohols. Heats have also been obtained in certain ethers including the dialkyl ethers. The solvent molecules are considered to be chains of two types of segments: CH2CH2 and COO, or CH2O. The heat of mixing is ascribed to two contributions: I, a difference in force fields between segments of polymer and solvent molecules, and II, a difference in the Prigogine structural factors of the molecules. Contribution II has been assumed to be approximately the same as with n‐alkane solvents of corresponding chain lengths. By subtracting heats found with n‐alkane solvents from those with esters or ethers II is eliminated and the resulting difference in I may be treated using a lattice model and assuming random mixing. This approach is successful for the ester solvents but somewhat less so for the ethers, where some departure from randomness due to steric factors may be present.

Cohesive‐energy‐densities of high polymers. Part. III. Estimation of C. E. D. by viscosity measurements

AbstractThe intrinsic viscosities and the slopes of ηsp/C against C were estimated for natural rubber, polystyrene, and polyisobutene in hydrocarbon and high mol.wt. alkyl ester solvents. Whereas no correlation could be established between slopes and c.e.d. (cohesive energy‐densities) balance of the systems, the plot of [η] versus δ, the solubility parameters of the solvents, yielded smooth curves similar to those obtained by plotting swelling coefficients against δ. GEE's method of estimating δp from swelling coefficients, was therefore extended to estimate δp from viscosity measurements. The present values of δp are in good agreement with those obtained by swelling measurements.

Cohesive‐energy‐density of high polymers. Part IV. C. E. D. of Polyacrylates

AbstractThe solubility parameters of polymethyl, ‐ethyl, ‐propyl, and ‐butyl acrylates were estimated by measuring their solution viscosities in a series of alkyl ester solvents. The results agreed well with those obtained by swelling measurements and it was observed that in the homologous series, c.e.d.8 decreases with increase in the alcoholic chain length.

2-Methyl-5-Vinylpyridine Elastomers in Oil-Resistant Service

Abstract Butadiene-MVP copolymers and butadiene-acrylonitrile-MVP terpolymers are a new class of rubbers which can be rendered oil-resistant by reaction with organic halogen compounds during vulcanization. The rubbers respond normally to reinforcement by carbon black and are highly reinforced by mineral fillers such as clay. Oil resistance depends on MVP content of copolymers and MVP and acrylonitrile content of terpolymers. The type and quantity of quaternizing agent also regulate the properties and oil resistance of the vulcanizates. Excellent performance of the experimental rubbers was demonstrated after immersion in ketones, amyl alcohol, ethyleneglycol, acid, caustic soda, a 70/30 2,2,4-trimethylpentane-toluene mixture, and ester solvents. The terpolymers offer better resistance to aromatic hydrocarbons. The experimental rubbers are also superior to the butadiene-acrylonitrile control compounds in contact with hot diester lubricants, giving much higher tensile strength after exposure for 72 hours at 300° F or 48 hours at 158° F. The MVP-containing rubbers possess excellent resistance to flex crack growth. They are also considerably better than the controls in resistance to blowout under severe conditions of rapid cyclic deformation under heavy load at elevated temperatures.