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1.
G. Reese 《European Journal of Lipid Science and Technology》1966,68(9):763-765
Sorption Processes of Amines on Hair Keratin Methods for the measurement of adsorption of amines as well as their salts on hair keratin were worked out. The adsorption of ethylamine was studied with relation to its concentration, time of action and pH value and compared with the adsorption of other amines. It was found that the adsorption of free amines from aqueous solution is dependent on the unassociated part and therefore is determined by basicity constant and pH value. Moreover, chain length and solvent have a decisive effect. In case of alkylammoniumhalogenides, the adsorption increases with the chain length of alkyl rest whereas in case of free amines it decreases with the chain length. The adsorption from aqueous solution is generally higher than from propanolic solution. 相似文献
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H. Reinheckel R. Gensike F. Falk G. Sonnek 《European Journal of Lipid Science and Technology》1969,71(9):792-795
Preparation of Branched Carboxylic Acids Free from Isomers A method for the preparation of branched saturated and unsaturated carboxylic acids, free from isomers, from tertiary γ-lactones by means of alkyl aluminium chlorides is reported. Saturated branched carboxylic acids were obtained in high yields by the reaction with ethyl aluminium chloride, whereas the reaction with diethyl aluminium chloride yielded the unsaturated acids. Splitting of lactones with mixtures of both the ethyl aluminium chlorides gave mixtures of saturated and unsaturated acids. The structure of the unsaturated carboxylic acid was determined by hydrogenation, ozonolysis, iodine value and gas chromatography. 相似文献
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Autoxidation of Methyl Linoleate in Water V: Isolation and Identification of Some Medium Chain Carboxylic Acids From the product of autoxidation of methyl linoleate the following carboxylic acids were isolated and identified as their N,N-dimethyl-p-aminobenzolazophenacyl esters: monomethyl suberate, α-hydroxy oenanthic acid, 4-hydroxy-2-transnonenoic acid, 4-hydroxy-12-carbmethoxy-2-trans-dodecenoic acid, and an ω-carbmethoxy carboxylic acid of unknown chain length. 相似文献
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J. Zajíc 《European Journal of Lipid Science and Technology》1973,75(2):85-88
Adsorption of Fatty Acids on Ion Exchangers The author examined the adsorption of saturated fatty acids C10 to C18 on strong- and weak-basic anion exchangers in the presence of n-hexane, acetone and 96% ethanol. The extent of adsorption on dried anion exchangers is small, and in nonpolar solvents, the effective capacity amounts to 5% of the theoretical capacity. With wetted resins, not the polarity of the solvents but the dissociation of the functional groups of the exchanger is the factor determining adsorption. Since the adsorbing ability of the exchanger is limited by the length of the fatty acid molecules, the effective capacity of strongly basic exchangers amounts only to one-third or a half of the theoretical capacity. 相似文献
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The Effect of the Use of Dihydric Alcohols in the Alkyd Resins Based on Branched Chain Fatty Acids By the modification of alkyd resins, based on the branched chain fatty acids with dihydric alcohols, the properties of the resins are strongly influenced. Not only the length but also the structure of the chain between two hydroxyl groups of the dihydroxy alcohol exert a considerable influence on the mechanical properties of the lacquer film. In addition, the structure of this chain is also important for the chemical resistance. The influence of the dihydroxy alcohol on the mechanical properties of the hardened lacquer films is partly due to the greater flexibility of the cross-linked system and partly due to the better plasticizing effect of the unbound alkyd part. 相似文献
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Preparation of Alkyleneglycol Monoesters by Alkoxylation of Carboxylic Acids A new process of alkoxylation using amines as catalysts is reported for the preparation of alkyleneglycol monoesters of aliphatic carboxylic acids. Prim., sec. and tert. amines act as highly selective catalysts at about 80°C. The monoester contents amount to 85–100%. The formation of diester and polyglycol is almost completely suppressed. 相似文献
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Preparation of Imidazolines of Fatty Acids The formation of imidazolines was studied in the reaction of diethylene triamine with fatty acids and oils. With the aid of IR- and UV-spectroscopy, it could be proved that imidazolines are formed at temperatures between 150° - 200° C. Aminoamides are also formed at these temperatures. Above 280° C, decomposition takes place, and low molecular nitrogen compounds, including probably ammonia, are formed. 相似文献
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Copolymer Latices Based on Vinyl Acetate and Vinyl Esters of Carboxylic Acids Derived from Propylene Tetramer Vinyl esters of carboxylic acids prepared from propylene tetramer were obtained by interesterification with vinyl acetate and the parameters for the copolymerization with vinyl acetate were determined. The properties of latices and coating films were evaluated with reference to the composition of the copolymer. Compared to other types of latices, coating films based on the above copolymers exhibit good properties. Especially, the resistance towards diluted alkali is excellent. 相似文献
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Tryptamides of Hydroxy-Carboxylic Acids in Oil-Containing Seeds Different amounts tryptamides of 5-hydroxy-carboxylic acids have been found in various oil-containing plant seeds, especially on their outer surface or in external layers of the tissues. In each variety, the substance present in highest concentration has been thoroughly investigated. It was found that the single fractions on thin-layer chromatograms were composed of several tryptamides of 5-hydroxy-carboxylic acids. Fatty acids ranging from C16 to C24 were detected. The antioxidative action of these tryptamides are discussed with examples. 相似文献
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G. Hübner 《European Journal of Lipid Science and Technology》1966,68(4):290-292
Vinylation of Higher Carboxylic Acids on Catalyst Melt After some references about the possibilities of the use of vinyl esters of higher carboxylic acids, some known methods for the synthesis of these are described in short. A new method is then reported whereby the vinylation of the α-position of branched chain higher carboxylic acids is discussed. 相似文献
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Oxy Acids in the Assessment of Thermally Treated Fats The usual characteristic values such as peroxide, aldehyde and epoxide values are mostly insufficient for the assessment of the degree of oxidation of thermally treated fats. Characteristics such as acid value and especially colouration with alkali and oxy acids offer a good insight into the degree of oxidation of a fat. According to the investigations carried out till now a good correlation exists between the alkali colouration and the oxy acids so that the determination of either of the two suffices. The measurement of alkali colouration is preferred, since it is simple and rapid, and permits the simultaneous assessment of oxy acids. 相似文献
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Synthesis of Aldehydes and Carboxylic Acids by Catalytic Oxidation of Vicinal Diols Results of studies on oxidative cleavage of aliphatic vicinal diols by oxygen in the presence of cobaltous compounds are reported. The effect of experimental conditions on the yield of aldehydes and acids are presented. Yields of 90% resp. 86% of these compounds are obtained. 相似文献
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Catalytic Influence of Haemin and Haemoproteids in the Oxidation of Polyenoic Acids In alkaline solution, the oxidation of linoleic acid catalysed by haemin proceeds as a first order reaction. Deviations from ideal form of equation for the reaction occur due to colloidal state of linoleic acid. Also in neutral region, the catalytic reaction proceeds as a first-order reaction with reference to surface-concentration of linoleic acid. Thereby, an inhibition is caused by the product of reaction. The catalysis is not specific for cis- or trans double bonds. On the other hand, haemin is catalytically ineffective in the oxidation of conjugated acids. Hence it is assumed that catalytic oxidation does not proceed as a chain reaction. Instead of this, by an electromeric effect absorbed haemin displaces the double bonds of linoleic acid towards conjugation and thus enables addition of oxygen. 相似文献
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Pyromellitic dianhydride (PMDA) was condensed with oxalic- and malonic-acid dihydrazides. The optimum experimental conditions have been worked out and the viscosity values were determined. The polyhydrazid carbonic acids so obtained were converted to the corresponding polymidimidcompounds by means of thermal cyclisations. Similar polycondensations were carried out with 3,3′-disulfo-4,4′-dicarboxy-diphenylsulfondianhydride and different hydrazides. The same dianhydride was also used for the synthesis of the carbodihydrazide. Further a sulfondihydrazide was prepared from 4,4′-ditolysulfon-3,3′-disulfochlorid. 相似文献
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C. Führer 《化学,工程师,技术》1971,43(15):849-853