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1.
将马来酸酐(MA)先聚合为低聚物聚马来酸酐(PMA),然后再与脂肪醇反应生成一种低聚表面活性剂.聚合反应主要受溶剂种类的影响,而酯化方法对酯化反应影响比较大,在丙酮中以三乙胺催化回流制备聚马来酸单脂肪醇酯(PMAM)的较佳工艺条件为:m(丙酮):m(PMA)=2.0:1,反应时间4 h,催化剂用量1.0%(相对于PMA的质量).PMA经脂肪醇改性、烧碱液中和后生成聚马来酸单脂肪醇酯钠盐(PMAMS).产品用IR和GPC进行表征,测定了产品的表面活性数据cmc、?cmc以及乳化力等. 相似文献
2.
D. N. Bhattacharyya S. Krishnan R. Y. Kelkar S. V. Chikale 《Journal of the American Oil Chemists' Society》1984,61(12):1925-1928
Oil soluble polyethylene glycol (PEG-1500) diesters of stearic, 12-hydroxystearic, oleic and 12-hydroxy oleic (ricinoleic)
acids were prepared by standard condensation reaction procedure. The surface active/emulsifying properties of the products
were evaluated by determining interfacial tension and through performance test in making water-in-oil emulsion. The presence
of double bond or hydroxyl group in the C18 acids, PEG content of reacting mixture, and nature and concentration of the catalyst in preparing the emulsifier all were
found to have great bearing on the emulsifying property and stability of w/o emulsions, particularly when the aqueous phase
contained a significant quantity of ions. Only the first factor, the effect of double bond and/or the hydroxyl group, is discussed
in this paper. 相似文献
3.
Sugar fatty acid esters are surfactants that are widely used in food, cosmetics, and pharmaceutical industries. In this study, enzymatic production of d-sorbitol monoesters with various fatty acids (C10–C18) was assessed. Reactions were performed in tert-butanol at 40 °C, catalyzed by Candida sp. 99–125 lipase. Dissolution of the substrates was found to be the limiting step of the reaction, and hence preheating was performed to increase the solubility of d-sorbitol. Thus, the yield of d-sorbitol palmitate was increased from 7.34 to 31.6 mM. The results demonstrated that the specific lipase preferred long-chain fatty acids. The surface-active properties of the products were also determined. 相似文献
4.
T. Naveen Kumar Y. S. R. Sastry G. Lakshminarayana 《Journal of the American Oil Chemists' Society》1989,66(1):153-157
Fatty acid mono- and diesters of diglycerol constitute the major portion of commercial polyglycerol esters; hence, their composition
influences the performance of the latter as emulsifiers. The correlation of structure of the fatty acids in the mono- and
diesters with surfactant properties is of interest. Linear diglycerol was isolated from polymerized glycerol by acetonation,
fractional distillation and regeneration. Diglycerol mono- and diesters of undecenoic, lauric, stearic, oleic and ricinoleic
acids were prepared by reacting diglycerol and fatty acids in a refluxing mixture of acetonitrile-tetrahydrofuran (75:25)
in the presence of p-toluenesulfonic acid and molecular sieves. Mono- and diesters were separated by silica gel column chromatography,
and their purities were ascertained by thin layer chromatography and determination of saponification value. The structures
were confirmed by periodic acid oxidation, chemical-ionization mass spectrometry and 13 C-NMR spectroscopy. Surfactant properties
of the esters were determined. Monoesters showed higher ability in surface tension reduction, emulsification and foaming than
the diesters. Short-chain fatty acid esters showed better surfactant properties than the long-chain fatty acid esters. The
presence of a central double bond in the lipophilic part of the monoesters reduced emulsion stability. The presence of a hydroxy
group in acyl chain retarded foaming and surface tension reducing power. 相似文献
5.
采用间接酯化法,以柠檬酸和乙酸酐为原料,先合成柠檬酸酐,后与醇醚糖苷(含有未反应的脂肪醇醚)反应,合成了醇醚糖苷柠檬酸单酯,再用NaOH溶液、饱和Ca(OH)2水溶液和Mg(OH)2乳浊液中和制得醇醚糖苷柠檬酸单酯二钠盐(MAEG-EC-Na)、醇醚糖苷柠檬酸单酯钙盐(MAEG-EC-Ca)和醇醚糖苷柠檬酸单酯镁盐(MAEG-EC-Mg),对产物的物化性能进行了测定。结果表明,上述3种产品的γcmc变化范围均很小,而柠檬酸单酯二钠盐的cmc最小,柠檬酸单酯盐起泡性能、泡沫稳定性的顺序为MAEG-EC-Mg>MAEG-EC-Ca>MAEG-EC-Na。 相似文献
6.
Preparation and surface- active properties of new amphipathic compounds with two phosphate groups and two long- chain alkyl groups 总被引:5,自引:0,他引:5
Yun- peng Zhu Araki Masuyama Mitsuo Okahara 《Journal of the American Oil Chemists' Society》1991,68(4):268-271
New compounds bearing two dihydrogen phosphate groups and two long- chain alkyl groups (octyl or decyl) were prepared in good
yields by the reaction of 1,ω-bis(alkyloxymethyl)- oligo (ethylene glycol)s with polyphosphoric acid.
Amphipathic di- or tetrasodium phosphates were obtained by neutralization of the free acids with sodium hydroxide, and their
surface- active properties in water were measured. Almost all these di- or tetrasodium phosphates showed good water solubility.
Their abilities to form micelles and to lower surface tension were fairly good as compared with general monoalkyl phosphates
consisting of one longer alkyl chain and one hydrophilic group. The foaming property of aqueous solutions of the tetrasodium
salts was different from that of the disodium salts. The former showed very low foaming ability. 相似文献
7.
Araki Masuyama Ko-ichi Akiyama Mitsuo Okahara 《Journal of the American Oil Chemists' Society》1987,64(5):764-768
For the development of surfactants having an ability to interact with metal ions, hydroxamic acids containing a long-chain
alkyl[oligo(oxyethylene)] group were prepared. Any hydroxamic acid with an octyl, decyl or dodecyl group was made readily
soluble in water by introducing four oxyethylene units into the molecule. These water-soluble hydroxamic acids had a micelleforming
ability and acted as polyoxyethylene-type nonionic surfactants under acidic and neutral conditions. Additionally, those compounds
were found to form a water-soluble complex with ferric ion at pH 2, and these complexes also showed surface active properties. 相似文献
8.
S. T. Bauer Patricia R. Gill R. E. Price 《Journal of the American Oil Chemists' Society》1961,38(3):127-130
Esters of pure tall oil fatty acids and commercially available monohydric alcohols were prepared, distilled, and analyzed
for pertinent values. The tall oil fatty acid fraction used in the esterification contained approximately 0.6% rosin acids
with essentially equal distribution of fatty acids into oleic and linoleic acids. The use of various techniques, such as fast
cooling by the addition of cold water to ester solutien, vacuum topping before water washing, and/or use of carbon dioxide
as a blanketing gas resulted in the production of light-colored ester products. These esters, low in acidic impurities and
light in color, are another source of chemical intermediates for the preparation of plasticizers, cutting oils, hydraulic
fluids, and lubricants.
Presented at the 51st annual meeting, American Oil Chemists' Society, Dallas, Tex., April 4–6, 1960. 相似文献
9.
F. E. Luddy 《Journal of the American Oil Chemists' Society》1979,56(11):759A-759A
Summary The chemical composition, molecular configuration, and crystal structure of fatty acid molecules contribute to the more than
twenty distinct physical properties associated with this class of organic compounds. This discussion will be limited to only
a few of these fatty acid properties and will include melting and solidification phenomena, vapor pressure-boiling point relationships
and solubility behavior of fatty acids. 相似文献
10.
Polyoxyethylene esters of fatty acids: an alternative synthetic route for high selectivity of monoesters 总被引:1,自引:0,他引:1
Sharifah Bee Abd Hamid Fatimah Zahara Abdullah Syamala Ariyanchira Maria Mifsud Sara Iborra Avelino Corma 《Catalysis Today》2004,97(4):271-276
Esterification reaction of fatty acids with polyoxyethylenes has been studied in the presence of solid acid catalysts and the results are compared with those obtained with a classical homogeneous catalyst, p-toluene sulphonic acid. Solid acid catalysts showed very high selectivities for monoesters even under less favorable reaction conditions of 1:1 molar ratios of oleic acid to PEG. Excess amount of PEG is normally required to ensure high selectivity for monoesters in the presence of homogeneous catalysts. The yields for monoesters given by heterogeneous catalysts such as zeolites, HPA and nafion were comparable to that with p-toluene sulphonic acid after 24 h of reaction. Results suggest that solid acid catalysts are potential catalysts for selective synthesis of monoesters from oleic acids and PEG even under severe reaction conditions. A screening study of different solid acid catalysts showed ZSM-5, zeolite-β, and nafion to be better catalysts than zeolite USY and mordenite, the former giving higher selectivity and yield to monoesters. The results suggest that the most important parameters in optimization catalyst performance for monoesters production is the acid strength and less so on other properties such as shape selectivity and concentration of active sites. 相似文献
11.
Improved synthesis of sucrose fatty acid monoesters 总被引:3,自引:0,他引:3
M. Angeles Cruces Francisco J. Plou Manuel Ferrer Manuel Bernabé Antonio Ballesteros 《Journal of the American Oil Chemists' Society》2001,78(5):541-546
The base-catalyzed synthesis of four sucrose fatty acid esters (caprylate, laurate, myristate, and palmitate) was performed
in dimethylsulfoxide by transesterification of sucrose with the corresponding vinyl esters using disodium hydrogen phosphate
as catalyst. In using a molar ratio sucrose/vinyl ester 4∶1 and mild reaction conditions (40°C and atmospheric pressure),
yields were higher than 85%. The isolated sucroesters had a higher percentage of monoesters (≥90%) and a lower content of
diesters in comparison with commercial derivatives. In all cases, 2-O-acylsucrose was the major product (≥60%) in the monoester fraction. 相似文献
12.
Mono- and diesters of the short and medium chain acids were prepared with polyglycerols and compared with their corresponding
mono- and diglycerides. The physical and chemical properties of such partial esters of polyglycerols, particularly with respect
to their oil, water and solvent solubility are given. Polyglycerol esters become more hydrophilic as the molecular weight
of the polyol increases. Polyglycerol esters become less hydrophilic as the length of the aliphatic chain of the acid used
in esterification is increased. Polyglycerol esters of such short and medium chain fatty acids show promise in applications
where surface activity and emulsification, solubilization of oil and water systems is desired.
Presented at the AOCS Meeting, New York, October 1968. 相似文献
13.
E. W. Bell J. P. Friedrich L. E. Gast J. C. Cowan 《Journal of the American Oil Chemists' Society》1965,42(10):876-878
Saturated C18- and C20-cyclic alcohols have been prepared by catalytic hydrogenation of methyl esters from cyclized linseed monomeric acids, purified
saturated C18-cyclic acids, ethylene adduct of conjugated soybean fatty acids, and ethylene adduct of conjugated octadecadienoic acids.
The cyclic alcohols have also been prepared from free acids of crude cyclic linseed, cyclic linseed monomeric, and ethylene
adduct of 9,11,t,t,-octadecadienoic. Conversion of esters and acids was 88–99% by hydroxyl determination; by gas-liquid chromatographic analysis,
almost quantitative Hydrogenations were carried out with 10%, by weight, copper chromite catalyst, an initial hydrogen pressure
of 2,100 psi, and a temperature of 280C for 3–5 hr.
Preliminary evaluations indicate that saturated C18- and C20-cyclic alcohols have a potential use in cosmetic formulations.
Presented AOCS meeting in Minneapolis, Minn., 1963.
No. Utiliz. Res. & Dev. Div., ARS, USDA. 相似文献
14.
Unsaturated fatty acids with triple bonds are used as inhibitors of unsaturated fatty acid metabolism or cytochrome P450 reactions
because they are believed to be chemically inert. In this paper we use in vitro cytochrome C reduction to show that two commonly used triple-bonded unsaturated fatty acids are in fact potent electron transfer
agents and could affect the multiple cellular systems that are redox-modulated. 相似文献
15.
Maltose long-chain fatty acid esters (MFAE), esterified at the 6 and 6′ position, were synthesized with stearic, palmitic,
myristic, and oleic groups. Synthesis yields were 15–20% based on initial maltose present, and structural confirmation was
obtained using plasma desorption mass spectrometry and nuclear magnetic resonance spectroscopy. These surfactants have surface
tensions in the range of 34–36 dyn/cm at their critical micelle concentrations (CMC) of approximately 10−5–10−6 mol/L. The increased chain lengths have a marked effect, reducing CMC values for MFAE by approximately three orders of magnitude
over similar carbohydrate-based dodecyl chain sources. Within chain lengths between 14 and 18 carbons, the rate of change
in CMC is significant and decreases with increasing chain length for MFAE. The melting points of MFAE are approximately 40°C,
and the heat capacities range from 1.6 to 1.9 J/g·K. These numbers are comparable to those of sucrose esters, indicating their
applicability in similar uses. However, because MFAE, unlike sucrose, possess an anomeric carbohydrate carbon position, these
surfactants maintain their reducing nature and are susceptible to further derivatization. They are also synthesized from renewable,
economical carbohydrates and lipids and may provide an excellent alternative to pertrochemical-derived products. 相似文献
16.
M. J. Danzig J. L. O'Donnell E. W. Bell J. C. Cowan H. M. Teeter 《Journal of the American Oil Chemists' Society》1957,34(3):136-138
Summary Soybean fatty acids were conjugated with alkali, and the contained, conjugated dienoic acids were isomerized with iodine to
thetrans,trans configuration. Adducts were prepared from thesetrans,trans-conjugated acids by condensation with maleic anhydride and acrylic acid. The adducts were isolated, purified, and converted
to esters by using a variety of alcohols, including methyl, ethyl,n-propyl,n-butyl, and allyl alcohols. Esters made from saturated alcohols were converted into the corresponding epoxy derivatives.
All of the esters (except allyl) and all of the epoxy esters were compatible with an equal weight of polyvinyl chloride and
appeared to be primary plasticizers for this plastic. The epoxy esters were effective in inhibiting heat deterioration of
polyvinyl chloride.
Presented at fall meeting. American Oil Chemists' Society, September 23–26, 1956, Chicago, Ill. 相似文献
17.
18.
This study investigates the influence of three fatty acids (lauric acid, palmitic acid, and stearic acid) on biodegradable polymer blends based on poly(lactic acid) (PLA) and poly(butylene succinate) (PBS), containing different weight ratios (100:0, 100:2, and 100:4) of fatty acids on the transparency, mechanical properties, morphology, contact angle, and water vapour permeability. All of the blends were pressed into thin films and tested. The experimental results showed that the properties of the samples varied with chain length and amounts of the fatty acids. Thus, it could be concluded that use of fatty acids opens up new ways for the plasticisation of PLA/PBS blends for use as new bioplastics. 相似文献
19.
Acetate labeled with14C was infused into shoots of Ginkgo. Up to 16% of the radioactivity was incorporated into lipids. Most of it was found in
the leaves and stems, but after 9 days, the lipids of roots also contained an appreciable amount of radioactivity. Radioactive
palmitic, linoleic and other common acids were isolated as methyl esters; 5,11,14–20∶3 and esters of similar type were isolated
pure or together with their isomers of normal structure; anacardic acids were separated as such from the fatty esters. 相似文献
20.
M. J. Diamond T. H. Applewhite R. E. Knowles L. A. Goldblatt 《Journal of the American Oil Chemists' Society》1964,41(1):9-13
Several procedures are evaluated for synthesis of phosphorus-containing derivatives of some long-chain hydroxy-fatty acids,
including ricinoleic and lesquerolic acid and their hydrogenated products. The conventional method of preparing phosphate
esters by reaction of an alcohol with a dialkyl phosphorochloridate is unsatisfactory, but introduction of the dialkyl phosphoryl
group was accomplished by using dimethylformamide as catalyst. Phosphorus derivatives are obtained more conveniently by ester
interchange between a long-chain hydroxy compound and a low molecular weight dialkyl phosphite. Purification of the phosphite
esters was accomplished by partitoning between acetonitrile and petroleum ether and also by chromatography on a column of
silicic acid. Attempts to prepare phosphorus derivatives of the allylic hydroxyl of methyl dimorphecolate resulted in extensive
dehydration to the conjugated triene.
Presented at the AOCS meeting in Toronto, Canada, 1962.
A laboratory of the W. Utiliz. Res. & Dev. Div., ARS, U.S.D.A. 相似文献