N-butyl Formate Research Articles

A model study for release of plasticizers from polymer films through vapor phase

AbstractA model has been applied to release of plasticizers from polymer films through vapor phase, for which the overall rate of release may be generally determined by evaporation of the plasticizer from the surface of the film, and/or by migration to the surface at below saturation in the polymer. The experimental system employed made use of n‐butyl formate, diethyl‐phthalate, di‐n‐butylphthalate, and N,n‐butylbenzenesulfonamide as model molecules in polycaprolactam films, both with the aims of studying undesirable loss of plasticizers, and of simulating a model able to envisage releasing, at a constant rate, of any desired additive, with relatively high solubility and vapor pressure, to the content of packaging films. Experimental measurements were made (at 298–333 K) by investigating in a suitable cell the permeation of plasticizers both at concentrations below and above the saturation limit. Rate of evaporation of plasticizers from the membrane surface above the saturation limit, measured in this cell, were found to coincide satisfactorily with those calculated by application of the mass transfer theory to evaporation from a stationary liquid into a stirred gas, at a known velocity of gas flowing past the surface. From these latter rates and solubilities, the mass transfer coefficients H for evaporation could be obtained, as well as from experimental time lags the diffusivities Dp through the polymer membrane. In the light of the theoretical model a correlation was found between activation energies of H and evaporation enthalpies of the model molecules.

Additional Volatile Components of Palomino Film Sherry

Palomino film sherry (195L, 1976 vintage) was extracted with CH₂Cl₂ in a rotating drum extractor. The extract, freed of acids by washing with cold NaHCO₃, was fractionated by GC and analyzed by GC-MS, and determination of Kovats9 indices. Identified were 63 compounds, 14 for the first time in wine. Among these were 4-hydroxyheptanoic-, 4-hydroxyoctanoic-, 5-hydroxyoctanoic-, 5-hydroxydodecanoic-, 4-hydroxy-5-ketoheptanoic-, and a 4,5-dihydroxy acid lactones. Other new components were 2-hydroxybutyric acid, 1,3-dihydroxy-4-ethylbenzene, 4-allyl-2,6-dimethoxyphenol, <i>trans</i>-nerolidol, 2-furfuryl methyl ketone, 4-methoxyacetophenone, 1,3-dimethyl-2-acetylindole, and n-butyl formate. Of particular interest aong these new components were the 4-hydroxy-5-ketoheptanoic acid lactone and the 4,5-dihydroxy acid lactone which gave further confirmation for the pathway proposed for the formation of certain γ-lactones in fermentation systems. Previously known wine volatiles found in the sherry included 4 acids, 11 alcohols, 17 esters, 6 lactones, 6 phenols, 1 sesquiterpene, and 3 miscellaneous compounds.

Structures and formation of \documentclass{article}\pagestyle{empty}\begin{document}$ \left[{{\rm C}_{{\rm 4}} {\rm H}_{{\rm 8}} } \right]_{}^{_.^ + } $\end{document} ions

AbstractSeveral \documentclass{article}\pagestyle{empty}\begin{document}$ \left[{{\rm C}_{{\rm 4}} {\rm H}_{{\rm\ 8}} } \right]_{}^{_.^ + } $\end{document} ion isomers yield characteristic and distinguishable collisional activation spectra: \documentclass{article}\pagestyle{empty}\begin{document}$ \left[{{\rm 1-butene} } \right]_{}^{_.^ + } $\end{document} and/or \documentclass{article}\pagestyle{empty}\begin{document}$ \left[{{\rm 2-butene} } \right]_{}^{_.^ + } $\end{document} (a‐b), \documentclass{article}\pagestyle{empty}\begin{document}$ \left[{{\rm isobutene} } \right]_{}^{_.^ + } $\end{document} (c) and [cyclobutane]+ (e), while the collisional activation spectrum of \documentclass{article}\pagestyle{empty}\begin{document}$ \left[{{\rm methylcyclopropane} } \right]_{}^{_.^ + } $\end{document} (d) could also arise from a combination of a‐b and c. Although ready isomerization may occur for \documentclass{article}\pagestyle{empty}\begin{document}$ \left[{{\rm C}_{{\rm 4}} {\rm H}_{{\rm 8}} } \right]_{}^{_.^ + } $\end{document} ions of higher internal energy, such as d or e → a, b, and/or c, the isomeric product ions identified from many precursors are consistent with previously postulated rearrangement mechanisms. 1,4‐Eliminations of HX occur in 1‐alkanols and, in part, 1‐buthanethiol and 1‐bromobutane. The collisional activation data are consistent with a substantial proportion of 1,3‐elimination in 1‐ and 2‐chlorobutane, although 1,2‐elimination may also occur in the latter, and the formation of the methylcycloprpane ion from n‐butyl vinyl ether and from n‐butyl formate. Surprisingly, cyclohexane yields the \documentclass{article}\pagestyle{empty}\begin{document}$ \left[{{\rm linear butene} } \right]_{}^{_.^ + } $\end{document} ions a‐b, not \documentclass{article}\pagestyle{empty}\begin{document}$ \left[{{\rm cyclobutane} } \right]_{}^{_.^ + } $\end{document}, e.

Gas-chromatographic determination of impurities in acrylic acid

1. Based on the retention volume, the gas-chromatographic method made it possible to identify the following 13 impurities in acrylic acid: formaldehyde, acetaldehyde and acrylaldehyde; n-propyl, allyl, isobutyl, and n-butyl alcohols; n-butyl formate, isobutyl acetate and n-butyl acetate; formic, acetic, and propionic acids. 2. A method was developed for the gas-chromatographic analysis of the impurities in acrylic acid, which had a sensitivity of 10−4−10−5 mole%.

Gas-chromatographic determination of impurities in butyl methacrylate

1. In butyl methacrylate 22 impurities have been identified from the retention volumes by gas-chromatography: acetone, 1-butene, formaldehyde, acetaldehyde, propionaldehyde, n-butyraldehyde, n-propyl alcohol, butyl alcohol and its isomers, n-butyl formate, i-butyl acetate, s-butyl propionate, n-butyl acetate, n-butyl propionate, i-butyl methacrylate, i-butyl propionate, n-butylα-hydroxy-i-quinone. Several impurities remained uninterpreted. 2. A gas-chromatographic method of analyzing the impurities in butyl methacrylate has been worked out with a sensitivity of about 10−6 mole %.

Dipole moments of substituted chloroformates in dilute benzene solutions

The dipole moments of methyl, ethyl, n-propyl, n-butyl, amyl, and phenyl chloroformate as well as n-butyl formate in dilute benzene solution at 25 °C were determined. The experimental results suggest that the configuration of the chloro-esters differs from the configuration of the unchloroinated esters, viz. the ester hydrocarbon group and the chlorine atom are cis to each other.

Free-radical substitution in aliphatic compounds. Part XIV. The halogenation of esters of butan-1-ol

The chlorination of n-butyl formate, acetate, and trifluoroacetate, and the bromination of n-butyl acetate and trifluoroacetate have been studied in the gas phase by use of a static system. Chlorination is appreciably deactivated at the 1-position and slightly in the 2-position. Bromination is activated at the 1-position and slightly deactivated at the 2-position. From halogenations at a range of temperatures approximate Arrhenius parameters have been calculated for attack at each site. The difference in reactivity of different positions is principally determined by differences in activation energy although the pre-exponential factors for the substituted position are invariably lower than for the 4-position. The results are considered in terms of current theories.

Reactions of alkyl radicals. Part 3.—The methyl-radical-sensitized decomposition of n-butyl formate

Reactions of alkyl radicals. Part 3.—The methyl-radical-sensitized decomposition of n-butyl formate

THE PHOTOLYSIS OF ALKYL ESTERS

An attempt has been made to determine the primary processes in the gas and liquid phase photolysis of simple alkyl esters.The liquid phase photolysis of methyl, ethyl, n-propyl, and n-butyl formate has been briefly investigated. Besides the dissociation processes, two intramolecular rearrangements were found to occur.[Formula: see text]Process I takes place with approximately the same yield for all the formates studied. Process II occurs only when there is a β-hydrogen in the alkyl group.An investigation of the gas and liquid phase photochemical decomposition of esters other than formates showed the existence of the following primary processes:[Formula: see text]Processes VI and VII require β- and γ-hydrogens, respectively, in the Y and X alkyl groups. It was found that processes I and X occur mostly at short wavelength, while the other processes take place at long wavelengths as well.

アミド又はエステルによるアミンのアチル化に就て

Various types of aliphatic amines were formylated by formamide and ethyl formate. Acylation of benzylamine was carried out with formylmethylamine, formylethylamine, acetamide, n-butyl formate and ethyl acetate.