Methyl Ethyl Ketone Solution Research Articles

The behaviour of macromolecules of styrene-acrylonitrile-methyl methacrylate terpolymers in solution

Styrene-acrylonitrile-methyl methacrylate terpolymers of various compositions have been studied by viscometry and light scattering methods. The data obtained for solutions in ethyl benzene, toluene, benzene, chloroform, chlorobenzene, THF, methyl-ethyl ketone, 1,2-dichloroethane, 1,4-dioxane, pyridine, DMF and DMSO at 30±0·1° were processed by the Stockmayer-Fixman, Inagaki-Ptitsyn, Flory-Fox and Bogdanetski methods which enables one to obtain the K θ and B parameters. The values of K θ were compared with those obtained from the ▪ log K v=f(a) relationship and those calculated from direct measurement of intrinsic viscosity in θ conditions. The most accurate determination of the K θ parameter for the above copolymers was made by using the Stockmayer-Fixman equation.

Chromatographic behaviour of 4′-dimethylaminoazobenzene-4-sulphonyl derivatives of amines in liquid—solid systems

4′-Dimethylaminoazobenzene-4′-sulphonyl (dabsyl) derivatives or monoalkyl- and dialkylamines were chromatographed on thin layers of silica or octadecyl silica. Silica layers were eluted with heptane solutions of methyl ethyl ketone, dioxane and diisopropyl ether; satisfactory separations of dialkylsulphonamide compounds were obtained, however, the R F values of dabsyl derivatives of C 8–C 12 monoalkylamines were practically identical. The reversed-phase system, water + methanol (80–100%)— ODS-silica was selective for monoalkyl as well as dialkyl derivatives.

Assessment of branching in polymers from small angle X-ray scattering (SAXS): SAXS from model comb-branched polystyrenes

Comb-branched polystyrenes having both fixed backbone length and number of branches but variable branch lengths were prepared anionically. Small angle X-ray scattering of the model polystyrenes from methyl ethyl ketone (MEK) solutions at 25°C was examined and it is shown that the mass per unit length and cross-sectional radius of gyration increase with increasing branch length. A maximum appears in the Kratky plot for the branched polymers. While the linear polymer displays an essentially Gaussian segment distribution in solution, the branched polymers deviate considerably from the behaviour of the linear polymer under the same conditions.

The heat capacities and volumes of some low molecular weight amides, ketones, esters, and ethers in water over the whole solubility range

The densities and heat capacities per unit volume of aqueous solutions of propionamide, methylacetate, ethylacetate, methylethylketone and diethylketone, and bis(2-ethoxyethyl)ether were measured over the whole solubility range with a flow densimeter and a flow microcalorimeter. Most systems were studied at 10, 25, and 40 °C. Properties of the pure liquids were also measured whenever possible. The derived apparent molal volumes [Formula: see text] all decrease with concentration in the water-rich region, except with ethyl acetate which increases at high temperature. In general the more hydrophobic the solute the more negative the initial slope. All apparent molal heat capacities [Formula: see text] decrease as a function of concentration and the decrease is more important for more hydrophobic solutes. The apparent molal expansibilities [Formula: see text] are obtained from [Formula: see text]. They are positive for all solutes but, at low concentrations, they are smaller than the corresponding molar value of the pure liquid. Various factors affecting hydrophobic interactions are examined.

Quantitation of urinary m- and p-methylhippuric acids as indices of m- and p-xylene exposure.

The method described here enables the accurate indentification and subsequent analysis of urinary m- and p-methylhippuric acids. Urinary m- and p-methylhippuric acids were extracted with methyl ethyl ketone, and the extract was dehydrated with sodium sulfate anhydrate. Benzoxylation of these acids was performed by heating with phenacyl bromide and triethylamine in a methyl ethyl ketone solution. An aliquot of this solution was injected into a high performance liquid chromatography column packed with silica gel.

Kinetics of wax crystallization from methyl ethyl ketone solutions

Kinetics of wax crystallization from methyl ethyl ketone solutions

Photoconductivities of poly[γ‐(β‐N‐carbazolylethyl)‐L‐glutamate] and its charge‐transfer complex with 2,4,7‐trinitrofluorenone

AbstractPoly[γ‐(β‐N‐carbazolylethyl)‐L‐glutamate] (PCLG) was prepared by polymerizing the monomer which was synthesized by adapting the NCA method to a reaction product between L‐glutamic acid and N‐(β‐hydroxyethyl)carbazole. PCLG films were prepared on a quartz Nesa (In2O3) plate by casting technique. The charge‐transfer complex could be successfully formed only near the surface of the PCLG film by immersing the PCLG film into either a benzene or a methyl ethyl ketone solution of 2,4,7‐trinitrofluorenone (TNF), since both benzene and methyl ethyl ketone were poor solvents for PCLG and suitable solvents for TNF. A photocell was formed by depositing a translucent gold electrode with vaccum evaporation onto the immersed film. For a small content of TNF in both the immersed films and the homogeneously mixed films of PCLG with TNF, the photocurrent of PCLG was successfully sensitized by TNF, but the sensitized photocurrents retained the relation I>I in a similar way as the photocurrent of PCLG alone, where I was the photocurrent under illumination onto the positive Au electrode and vice versa. On the other hand, as the TNF content increased, I became remarkably greater than I. The PCLG polymer, therefore, can behave as a p‐type photoconductor, while the well‐doped PCLG‐TNF complex can behave as an n‐type photoconductor.

Rectification effects based on the p-n junction of poly[γ- (β-N-carbazolylethyl) -L-glutamate]— 2,4,7-trinitrofluorenone systems

In the dark and under illumination, it has been found that rectification effects in an organic photoconductor system are attributable to a p-n junction barrier. This junction was accomplished by a doping process similar to one used in inorganic semiconductors. The p-n junction barrier was made by immersing a poly[γ- (β-N-carbazolylethyl) -L-glutamate] (PCLG) film in either benzene or a methylethylketone solution of 2,4,7-trinitrofluorenone (TNF), since both benzene and methylethylketone are poor solvents for PCLG and are suitable solvents for TNF. PCLG and PCLG doped with TNF behave as p-type and n-type organic semiconductors, respectively, and a p-n junction with a continuous interface can be accomplished in the sandwich structure system of In2O3//PCLG/PCLG-TNF complex//Au. In this sample, rectification effects both in the dark and under illumination have been observed to be in good agreement with a theoretical equation of the p-n junction for inorganic semiconductors. However, the potential drop across the p-n junction barrier is depressed, being much smaller than the voltage applied externally to the photocell because of the remarkably high electrical resistivities of PCLG and the PCLG-TNF complex. Furthermore, even without an applied field—that is, with a short circuit—the photovoltaic current has been observed and attributed to the junction barrier. On the other hand, in the In2O3//PCLG//Au and In2O3//PCLG-TNF complex//Au systems it has been found that neither dark currents nor photocurrents attributable to a p-n junction are observed.

Conductance studies of salt solutions in the presence of poly(vinylbenzo crown ethers)

AbstractThe conductance of acetone and methyl ethyl ketone solutions of tetraphenylborate salts in the presence of homopolymers and styrene copolymers of vinylbenzo‐15‐crown‐5 and vinylbenzo‐18‐crown‐6 was studied, and the results compared with data obtained for crown ethers. Polycations are formed on binding cations to the poly(crown ethers), and the conductance behavior of the polyelectrolytes depends on the nature of the cation‐crown complex and the spacing between crown moieties which in turn determines the charge density on the polymer chain. The compositions of the crown‐cation complexes were determined for crown ethers. The complex formation constants of sodium and potassium cations to poly(vinylbenzo‐18‐crown‐6) were found to change as more cations bind to the chain. This is not the case for the copolymers where the crown ligands are spaced farther apart. A mixture of poly(vinylbenzo‐15‐crown‐5) and 10−3M potassium tetraphenylborate in methyl ethyl ketone or acetone has a minimum conductance at a crown to cation ratio of 3.0, but the conductance rapidly increases on addition of crown ether. This was used to qualitatively determine the binding efficiency of a series of crown ethers since the rate of increase in the conductance is a measure of the binding ability of the crown ether to the cation.

Epitaxial growth of solution grown polyvinylchloride (PVC) films

Thin films of polyvinylchloride (PVC) have been grown epitaxially from three different solvents onto the (001) plane of rocksalt crystals by the isothermal immersion technique. The ranges of values of the growth parameters (temperature and concentration of the solution and immersion time) over which epitaxial growth is obtained have been established in each case. Films grown from a benzene and acetone mixture show epitaxy only at temperatures of 58°C or more and with concentrations below 0.1 g/100 ml. The epitaxial relation is (010) [110] PVC∥(001) [110] NaCl. The crystallites in the epitaxial films are of pyramidal shape and the molecular chains are folded in a direction perpendicular to the substrate. Films grown from ethyl methyl ketone solution show epitaxy only at temperatures of 65°C or more for concentrations greater than or equal to 0.15 g/100 ml. Films grown from cyclohexanone solution show epitaxy over a wide range of temperatures and concentrations. The epitaxial relation is (001) [110] PVC∥(001) [110] NaCl and the crystallites are rod- or fibre-like. The molecular chains in these crystallites are folded in a direction parallel to the substrate. Our studies show that epitaxial growth occurs in the earliest stage of growth of the films and further growth results in a mixture of amorphous and polycrystalline regions. The mechanism of epitaxial growth is explained in terms of our model for the growth of polymer chains. Two possible configurations of the molecular chains in the unit cell of PVC on a (001) rocksalt surface are proposed to explain the two epitaxial orientation relations observed.

Determination of the Molecular Weight Distribution by Diffusion Measurement

A diffusion method is proposed for establishing molecular weight distribution of a polymer. The principle of the method makes use of the fact that the diffusion constant of monodisperse polymers is dependent on their molecular weight, and the diffusion curve of polydisperse polydisperse polymer is thought to be the summation over all curves of the components. The diffusion curve obtained from the interferometric method is expressed mathematically with Fredholm's integral equation of the first kind which provides the necessary relationship of molecular weight distribution and the diffusion constant of each component. A few errors might be inherently induced even in the most accurate measurement of the curve. Therefore, a new evaluating process is introduced for the numerical analysis of the curve. The flow chart is shown in Fig.2.The validity for the application of the method is examined by the diffusion measurement of polystyrene in ethyl methyl ketone solution by a Mach-Zehnder interferometer at a carefully controlled temperature. The distribution is determined for the especially prepared polymers whose distributions have been preliminary known. These experimental results support the validity or The justification of the present method. The method has an advantage that it does not require any calibration curves. In addition, a limitation involved in the method is also discussed.

Polymerization of methyl methacrylate by metallocenes

Attempts at polymerizing methacrylate using metallocenes are reported. Polymerization is successful using ferrocene in a ketone solution, but not in benzene or without a solvent. Ketones are effective in the order: methyl ethyl ketone < cyclohexanone < cycloheptanone. Carbon tetrachloride has an accelerative effect on the polymerization in benzene and methyl ethyl ketone solutions, but no effect in cyclohexanone solution. Some binary systems, which consist of ferrocene and higher valence compounds such as cobalt trisacetylacetonate, are effective redox initiators. Cobaltocene polymerizes methyl methacrylate in the presence of carbon tetrachloride; zirconocene dichloride induces polymerization of methyl methacrylate in a cyclohexanone solution; whereas neither nickelocene nor titanocene dichloride are effective. Styrene and acrylonitrile were not polymerized by the metallocenes examined.

Mixed chloride-bisulfate and iodide-bisulfate complexes of indium(III)

The partition ratio, D, of In(III) between aqueous chloride/bisuliate solutions of constant ionic strength (5.0) and methylethylketone (MEK) or methylisobutylketone (MIBK) has been investigated radiometrically as a function of chloride/bisulfate ratio and aqueous acidity. Similar experiments were also carried out with aqueous iodide/bisulfate solutions and MIBK. The plot of D versus halide/bisulfate showed a maximum in all cases. The dependence of D on aqueous acidity was found to be linear with MEK, but less than first power with MIBK. Results may be explained by assuming the extraction of all species represented by KtH +. InX m(HSO 4) − 4− m and InX n (HSO 4) 3− n Kt p, where Kt represents a ketone molecule, KtH + a solvated hydroxonium ion, m = 0, 1, 2, 3, or 4, n = 0, 1, 2, or 3 and p = 1, 2 or 3. Formation constants for these complexes have been calculated.

Ketone Extraction of Mixed Chloride-Bisulfate Complexes of Aluminum

Abstract The partition ratio D of Al(III) between aqueous chloride/bisulfate solutions of constant ionic strength (5.0) and methyl ethylketone (MEK) or methyl isobutyl ketone (MIBK) was investigated radiometrically as a function of the chloride/bisulfate ratio and aqueous acidity. With MIBK, the plot of D vs chloride/bisulfate showed a maximum. Results may be explained by assuming the extraction of the following species: KtH+·AlCl4-, KtH+-AlCl2(HSO4)2- and KtH+·Al(HSO4)4, where KtH+ represents a solvated hydrogen ion. Formation constants for these complexes were calculated.

Significance of solvation in the effectiveness of inhibitor action

It is shown that the effectiveness of inhibitors in the oxidation of methyl ethyl ketone is significantly less than in a hydrocarbon medium; this is due to the formation of hydrogen bonds between ketone and inhibitor. The elementary rate constants of the interaction of the RO 2 . radical of methyl ethyl ketone with α-naphthol and phenol derivatives \(k_{i_1 } \)were measured. In aqueous solutions of methyl ethyl ketone, the k i exp value for all inhibitors drops with increasing H2O concentration. The interaction constants of solvated RO 2 . ...H2O peroxide radicals with the inhibitor and the equilibrium constants for the formation of H-bonds between inhibitor and water were studied. The k i exp with hydroquinone in the oxidation of C4H8O in acetic acid were measured.

Effectiveness of the action of inhibitors in the oxidation of methyl ethyl ketone in solutions of alcohols

1. The influence of methyl, ethyl, and tert-butyl alcohols on the effectiveness of the action of inhibitors (phenol derivatives) in the oxidation of methyl ethyl ketone was investigated. 2. When methyl ethyl ketone is diluted by alcohols, the effective rate constant of the interaction of peroxide radicals of methyl ethyl ketone with the inhibitor drops. 3. The decrease in the effectiveness of inhibitors in alcohol solutions of methyl ethyl ketone is associated with the ability of alcohols to form a hydrogen bond with inhibitor molecules and with peroxide radicals of methyl ethyl ketone. 4. For solutions of methyl ethyl ketone in tert-butyl alcohol, values of the rate constants of the elementary steps of the reactions of RO2. with inhibitors and the equilibrium constants of the formation of hydrogen bonds between the alcohol and inhibitor molecules were obtained. The results were compared with the data obtained in the oxidation of methyl ethyl ketone in aqueous solutions.

Graft polymers from poly(vinyl chloride) and chlorinated rubber

AbstractGraft polymers from poly(vinyl chloride) (PVC) and chlorinated rubber (CIR) with side chains of poly(methyl methacrylate) (PMMA), poly(methyl acrylate) (PMA), or poly(ethyl methacrylate) (PEMA) were synthesized. For this purpose, a vinyl monomer was polymerized in the presence of small quantities of PVC or CIR with benzoyl peroxide as catalyst. The graft polymers were separated from both homopolymers by precipitation with methanol from methyl ethyl ketone solutions of the reaction products and the grafting efficiency was calculated. The graft polymers were characterized by infrared spectra, elemental analysis, NMR, and osmometric or light‐scattering determinations. From the results it is concluded that the PVC or CIR molecules contain side chains of PMMA, PMA, or PEMA. The graft polymers showed higher molecular weights, and the values of second virial coefficient for these polymers were much different from those of the starting polymers.

Graft polymers: Chain transfer and branching

AbstractThe vinyl monomers, methyl methacrylate, ethyl methacrylate, and methyl acrylate were polymerized in the presence of chlorinated rubber or poly(vinyl chloride) in homogeneous solution with benzoyl peroxide as catalyst. A graft polymer was formed by a chain‐transfer reaction involving the growing polymer radicals to the backbone of chlorinated rubber or poly(vinyl chloride), in addition to homopolymer from the monomer. The homopolymer was isolated from the polymer mixture by fractional precipitation from methyl ethyl ketone solution with methanol as precipitant. The chain‐transfer constants for the branching reactions were evaluated. The ratios kp/(kt)1/2 for the grafting reactions were obtained by a correlation of chain‐transfer constants with the extent of branching. The chain‐transfer data were correlated on the basis of an extension of the Q–e scheme of Alfrey and Price to polymer–polymer transfer reactions. Specific effects due to the backbone are found to have considerable influence on the course of the chaintransfer reactions and kp/(kt)1/2 of the grafting reactions.

Nickel(II), Cobalt(II) and Copper(II) Complexes of 2,2′-Diaminobiphenyl

Abstract Nickel(II), cobalt(II) and copper(II) complexes of 2, 2′-diaminobiphenyl were prepared in an autoclave under a high pressure and a high temperature as the acetates: Ni(C12H12N2)2-(CH3CO2)2, Co(C12H12N2)2(CH3CO2)2 and Cu(C12H12N2) (CH3CO2)2. They are sparingly soluble in water and in non-polar solvents, but are soluble in some polar solvents. The presence of a monomer complex was verified by a molecular weight determination in a methyl ethyl ketone solution for both the cobalt and copper complexes. Analytical, magnetic susceptibility, powder X-ray diffraction, diffuse reflection spectral, infrared spectral, and ESR spectral data are given, and the geometric isomerism of the complexes is discussed.

Solution Properties of the Methyl Methacrylate-Acrylonitrile Copolymer

Abstract Short-range interactions between chain units of random copolymers in solution may be influenced by the characters of the pendant side groupes or, more precisely, by the dipole moment of the substituent. In those experiments the steric factor was derived for a random copolymer composed of methyl methacrylate and acrylonitrile from the relation between the limiting viscosity number and the molecular weight. Mark-Houwink relations were obtained in N,N′-dimethylformamide (DMF) and in methyl ethyl ketone (MEK) at 30°C for the copolymer containing 0.48 mol fraction of acrylonitrile, and for polymethyl methacrylate (PMMA) for the sake of comparison: [η]=4.61×10−4M0.65 for the copolymer in DMF [η]=1.70×10−4M0.65 for PMMA in DMF [η]=1.26×10−3M0.52 for the copolymer in MEK With the Stockmayer-Fixman expression, these correlations become, respectively: [η]=213×10−5M1⁄2+12.4×10−7M [η]=78.2×10−5M1⁄2+5.05×10−7M [η]=163×10−5M1⁄2+1.05×10−7M The unperturbed mean square end-to-end distance, 〈L2〉0, determined from the first term of the latter expressions, together with the 〈L2〉0f value calculated by assuming the completely free rotation, gives the steric factor of σ=(〈L2〉0⁄〈L2〉0f)1⁄2 2.59±0.01 from the DMF solution; this factor is larger than that for polymethyl methacrylate (2.11±0.08),, and that for polyacrylonitrile (2.20+0.05). The steric parameter derived from the MEK solution is 2.37±0.05 for this co-polymer; this value does not agree with the value obtained from the DMF solution. In both cases, it may be concluded that the dimensions of the copolymer between acrylonitrile and methyl methacrylate are influenced by the electrostatic interactions between nitrile groups of acrylonitrile units and methoxy-carbonile and/or methyl groups of methyl methacrylate units. The second virial coefficient in MEK obtained from the light scattering measurements also has a larger value for this copolymer than for polymethyl methacrylate. This tendency of copolymers to show a larger second virial coefficient seems to be an essential characteristic of some copolymers.