首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 62 毫秒
1.
Surface properties of a series of highly purified linear alkyl benzene sulfonates were extensively studied in hard river water. The effects of water hardness, alkyl chain length and position of the phenyl sulfonate group in the molecule on such surface properties as pC20, critical micelle concentration (CMC), γCMC, CMC/C20 ratio, and minimum area per molecule at the interface are discussed in detail. The position of phenyl sulfonate group in the molecule was found to have a pronounced effect on the CMC, γCMC value, CMC/C20 ratio, and, to the contrary, a relatively small effect on the pC20 value. The linear relationship between pC20 or-log CMC, and m, the number of carbon atoms in the alkyl chain, was found for surfactants with the phenyl sulfonate group either at the terminal position or at the more central position in the molecule. γCMC decreases but the CMC value increases, when the position of phenyl sulfonate group moves from the terminal toward a more central position of the molecule, reflecting the “Hartley Effect” resulting from the branched alkyl chain.  相似文献   

2.
Alpha olefin sulfonates (AOS) are a complex mixture of the posi-tional isomers of hydroxyalkane sulfonates, alkene sulfonates, and disulfonates. This paper describes a qualitative method for separat-ing these various components by reverse-phase high pressure liquid chromatography. The column utilized was a DuPont Zorbax TMS (4.6 mm × 25 cm) with a water/methanol (25:75, v/v) mobile phase containing sodium nitrate at a concentration of 0.4M. The hydroxyalkane sulfonate and alkene sulfonate peaks were identified using laboratory prepared standards. The disulfonate peaks were located using controlled sulfonation conditions. More work needs to be done to separate an overlap of C16 3-hydroxyalkane sulfonate and C14 2-alkene sulfonate in 1416 AOS. However, if studies are based on single carbon number AOS samples, the overlap of these peaks can be avoided. This method can be utilized as a qualitative tool for the comparison of sulfonation runs, the identification of AOS within a detergent, or the identfication of the olefin type used for sulfonation.  相似文献   

3.
Single carbon cut α-olefin sulfonates (AOS) having 12, 14, 16 and 18 carbon chain lengths and several of their blends were prepared from high-quality α-olefins by continuous SO3 sulfonation in a laboratory falling film reactor. The ultimate biodegradability of these products was studied using a modified shake flask procedure with CO2 evolution as the major biodegradability criterion. For comparison, commercial samples of a modified Ziegler-based AOS, linear alkylbenzene sulfonates (LAS), and an alcohol ethoxysulfate (AEOS) were included. The results showed the AOS products bio-degraded to CO2 more completely than LAS and slightly less extensively than AEOS. CO2 evolution decreased slightly in amount and rate as AOS carbon chain length increased in the C14 to C18 range. Presented at the AOCS meeting, May 1977, New York City.  相似文献   

4.
Ca. 1% of the glycerides of milk fat contain oxofatty acids. The isolation, fractionation, and characterization of oxofatty acids were accomplished using the following sequence of steps: (A) transmethylation, (B) conversion into 2,4-dinitrophenylhydrazones, (C) adsorption of the 2,4-dinitrophenylhydrazones on magnesium oxide to eliminate the colorless lipid, (D) fractionation of the 2,4-dinitrophenylhydrazones into non-oxofatty acid and oxofatty acid fractions on alumina, (E) separation of the oxofatty acid 2,4-dinitrophenylhydrazones into saturated and unsaturated classes by argentation column chromatography, (F) separation of these classes by chain length using liquid-liquid column and thin layer partition chromatography, (G) resolution of positional isomers by thin layer chromatography, (H) regeneration of the positional isomer 2,4-dinitrophenylhydrazones, and (I) analysis of the parent oxofatty acids by gas liquid chromatographymass spectrometry. In this manner, 36 saturated and 11 unsaturated oxofatty acids were identified tentatively or positively. The saturated oxofatty acids ranged in chain length from C10–C24, predominantly C18 and C16, and generally contained an even number of carbon atoms. The unsaturated oxofatty acids ranged from C14–C18, with C18 predominating.  相似文献   

5.
A series of alkyl sulphobetaine Gemini surfactants Cn‐GSBS (n = 8, 10, 12, 14, 16) was synthesized, using aliphatic amine, cyanuric chloride, ethylenediamine, N,N′‐dimethyl‐1,3‐propyldiamine and sodium 2‐chloroethane sulfonate as main raw materials. The chemical structures were confirmed by FT‐IR, 1H NMR and elemental analysis. The Krafft points differ markedly with different carbon chain length, for C8‐GSBS, C10‐GSBS and C12‐GSBS are considered to be below 0 °C and C14‐GSBS, C16‐GSBS are higher than 0 °C but lower than room temperature. Surface‐active properties were studied by surface tension and electrical conductivity. Critical micelle concentrations were much lower than dodecyl sulphobetaine (BS‐12) and decreased with increasing length of the carbon chain from 8 to 16, and can reach a minimum as low as 5 × 10?5 mol L?1 for C16‐GSBS. Effects of carbon chain length and concentration of Cn‐GSBS on crude oil emulsion stability were also investigated and discussed.  相似文献   

6.
Performance of sulfoxylated fatty acid methyl esters   总被引:3,自引:0,他引:3  
Sulfoxidation of fatty acid methyl esters with SO2, O2, and ultraviolet light of appropriate wavelength has led to the synthesis of methyl esters sulfonates or sulfoxylates known as Φ-MES because of the possible random position of SO3 group in the alkyl chain. This work describes experimental measurements of physical properties such as solubility and viscosity of sodium Φ-MES water solutions. Amphipathic properties such as surface tension, critical micelle concentration, wetting and foaming powers were measured as well and compared to linear alkylbenzene sodium sulfonate (LAS). Finally, stability to water hardness, dishwashing test, and detergency performance were evaluated. Expectedly, these products may be used as LAS partners either in heavy-duty powders or in hand dishwashing liquids. Experimental results on Φ-MES of varying carbon number indicate that C16 is the optimal carbon chain length.  相似文献   

7.
The jaw fat of the Atlantic bottlenose dolphin (Tursiops truncatus) contains unusual wax esters which can be separated into short chain (<C24) and long chain (>C24) fractions by thin layer chromatography. The short chain wax esters (28 wt. %) have been characterized as a 72∶24∶4 mixture of isovaleroyl, isobutoryl, and 2-methylbutyrol, esters of C14–C18 n- and iso-alcohols. The intact <C24 esters have been resolved into individual molecular species by gas liquid chromatography on open-tubular polyester columns. The long chain wax esters (12 wt. %) contain C10–C22 n- and iso-acids esterified to the same C14–C18 n- and iso-alcohols. Gas liquid chromatography of the intact, hydrogenated >C24 esters on a short JXR column has characterized them according to carbon number and the number of methyl branches they contain.  相似文献   

8.
稳态荧光探针研究支链烷基苯磺酸钠的聚集行为   总被引:4,自引:6,他引:4  
以芘为荧光探针、二苯酮为猝灭剂,用稳态荧光探针法测定了合成的4种带干扰基(磺酸基邻位的短链烷基)的支链烷基苯磺酸钠的临界胶团浓度、合适猝灭剂浓度下的胶团聚集数以及在不同浓度氯化钠水溶液中的胶团聚集数.结果表明,支链烷基苯磺酸钠分子中长链烷基碳数增加,临界胶团浓度大幅度降低,胶团聚集数减小;分子中短链烷基碳数增加,临界胶团浓度降低幅度小,胶团聚集数增大;胶团聚集数随氯化钠浓度增大而增大.  相似文献   

9.
The properties of alpha-olefin–sulfur dioxide copolymer prepared from the series C8–C18 (even-numbered) alpha-olefins and sulfur dioxide are described. These polymers undergo clean thermal degradation and have high permeabilities to oxygen and carbon dioxide. Maximum permeabilities, maximum per cent elongation at the yield point, and minimum density are obtained with the C16-based polymer. An explanation is proposed involving a competitive plasticizing/side chain crystallization effect.  相似文献   

10.
Phenyl isomer distributions, within current commercial limits of HF and A1C13 linear alkylbenzene sulfonates (LAS), have little effect on dishwashing performance in light-duty liquids (LDL), detergency performance in heavy-duty powders (HDP), and interfacial tension value. The most important factor in determining performance differences among commercial LAS samples is carbon chain homolog distribution. Both HF and A1C13 LAS perform equally well and can be used interchangeably in high-performance products. The optimum for foam stability in light-duty liquids shifts towards shorter alkyl chain length as water hardness increases. At 0 ppm water hardness the optimum occurs at C13: at 50–150 ppm the optimum moves to C11 and C12; and above 150 ppm the optimum shifts to include C10, C11 and C,12. The detergency performance optimum range in a phosphate built heavy-duty powder at 50 and 150 ppm water hardness includes the C12, C13 and C14 alkyl chain lengths. In a nonphosphate built powder the optimum is similar at 50 ppm hardness to that of a phosphate built powder, but shifts at 150 ppm hardness to include C11, C12 and C13.  相似文献   

11.
A gas Chromatographic method is described for the analysis of tetradecane-l,4-sultone (C14 delta sultone) and the combination of 2-chlorotetradecane-1,3-sultone (C14 2-chloro gamma sultone), and 1-tetradecene-l,3-sultone (C14 unsaturated gamma sultone) in neutral oils isolated from olefin sulfonate. Samples of the neutral oil are diluted in hexane and injected directly into the gas Chromatograph. Quantitative data are obtained by comparison to known amounts of the respective sultones. Through the use of silica gel column chromatography followed by gas chromatography of collected fractions, separation and individual quantitation of the 2-chlorotetradecane-1,3 sultone and l-tetradecene-l,3-sultone can be obtained. Routine use for control purposes has shown the method to be reliable and interlaboratory agreement of data has been good.  相似文献   

12.
The analysis of nonionic surfactants was investigated by reversed-phase liquid chromatography with mass spectrometry detection. On a C18 column, separation was achieved on the basis of chain lengths of both alkyl and ethoxy groups in a CH3CN/CH3OH/H2O/HAc solvent system. Peaks were identified by electrospray mass spectrometry.  相似文献   

13.
Cuticular waxes are complex mixtures consisting mostly of very‐long‐chain aliphatics with single, primary functional groups. However, the waxes of many plant species also include aliphatics with one or more functional groups residing on subterminal or mid‐chain carbons. In the present work, the cuticular wax mixtures from flag leaf blades and peduncles of Triticum aestivum cv. Bethlehem were analyzed in a search for novel wax constituents with in‐chain functionalities, potentially of polyketide origin. The structures of compounds belonging to six different compound classes were elucidated using gas chromatography–mass spectrometry of various derivatives. Among them, a series of 2,4‐ketols was identified, with odd carbon numbers ranging from C25 to C37 and peaking at C33. The analogous C33 2,4‐diketone was identified as well, together with a pair of co‐eluting C31 mid‐chain β‐ketol isomers (16‐hydroxyhentriacontan‐14‐one and 14‐hydroxyhentriacontan‐16‐one), a pair of co‐eluting C30 mid‐chain α‐ketol isomers (15‐hydroxytriacontan‐14‐one and 14‐hydroxytriacontan‐15‐one), the corresponding C30 14,15‐diketone, and a pair of co‐eluting C31 ketones (hentriacontan‐14‐one and hentriacontan‐16‐one). All newly discovered structures contain ketone functional groups, with similar C13H27 and C15H31 alkyl chains on either side of the functionalities, thus resembling the previously reported very‐long‐chain β‐diketones dominating the wheat wax mixtures. Based on these structural characteristics, possible biosynthetic pathways leading to the newly identified polyketide‐like compounds are proposed.  相似文献   

14.
This paper deals with the synthesis of a series of alkyl m-xylene sulfonate isomers (with the m-xylene located at the eighth carbon atom along the long alkyl chain) by the Friedel?CCrafts reaction, and the Grignard reaction followed by hydrogenation. The structures were confirmed by 1H NMR. All analytical methods indicated high levels of purity of the isomers with the eighth carbon atom at the long alkyl chain. The critical micelle concentration (CMC), surface tension and maximum surface excess concentration at the CMC and area per molecule at the interface were determined. As the long alkyl chains increased the surfactant molecule tends to pack closely at the gas?Cliquid interface. Accordingly, the CMC decreased, the adsorption density increased, and the surface tension reduction was strengthened.  相似文献   

15.
J. J. Myher  A. Kuksis  S. Pind 《Lipids》1989,24(5):396-407
This study reports the application of modern methods of molecular species analysis in determination of the structure of both major and minor glycerophospholipids and sphingomyelins of human erythrocytes. Individual phospholipid classes were resolved from total lipid extracts by thin-layer chromatography. Diradylglycerols were released by phospholipase C and converted into trimethylsilyl ethers, which were resolved into the alkenylacyl, alkylacyl and diacylglycerol subclasses by normal phase high performance liquid chromatography. Molecular species of diradylglycerols and ceramides were quantitated according to carbon and double bond number by gas liquid chromatography using a fused silica capillary column wall-coated with bonded RTx-2330. The molecular species of ceramides were determined by GC/MS. The diradyl glycerophosphocholines contained 93.0% diacyl, 4.6% alkylacyl and 2.5% alkenylacyl, white the diradyl glycerophosphoethanolamines were made up of 48.8% diacyl, 47.8% alkenylacyl and 3.4% alkylacyl subclasses. Analysis of the molecular species showed that the long chain polyunsaturated acids were mainly combined with C16 in all diradyl GPC subclasses and in diacyl GPE, while in the alkylacyl and alkenylacyl GPE and in diacyl glycerophosphoinositol and diacyl glycerophosphoserine they were combined mainly with C18 saturated fatty chains. In addition to the C16 and C18 alkyl and alkenyl, the ether fractions also contained significant proportions of C20, C22 and C24 chains. The molecular species of the ceramide moieties of the SPH were made up largely of mono- and diunsaturated species. Over 200 molecular species were identified and quantitated in a representative sample of human red blood cells.  相似文献   

16.
Alpha olefin sulfonate (AOS) can be made by SO3-air sulfonation of straight chain alpha olefins followed by saponification of the neutralized product. The sulfonation step forms unsaturated sulfonic acids, sultones and sultone sulfonic acids. Hydrolysis of the various sultones yields a mixture of unsaturated and hydroxy sulfonates. Sulfonation of commercial mixtures of straight chain alpha olefins in a large-scale SO3 falling film unit has given AOS of 1.5–3.0% oil based on active content and tristimulus color of about 40% saturation (2% solution) which is readily bleachable with 1–3% NaOCl to about 10–15% saturation. Performance of AOS made from C15−C18 alpha olefin is comparable to that of the high-foaming C11−C14 LAS in both detergency and dishwashing foam. It is superior to similar products made from internal straight chain olefins. The product shows a low order of toxicity and biodegrad-ability slightly better than that of LAS. A C15−C16 AOS blend is especially attractive in liquid detergent formulations. Presented at the AOCS Meeting, Los Angeles, April 1966.  相似文献   

17.
A variety of commercially available tetralkyl (R1R2R3R4N+) ammonium chlorides and methyl sulfate salts were examined under phase transfer conditions. For conversion of benzyl chloride to benzyl acetate with aqueous potassium acetate, tri C8–10 methyl ammonium chloride was the most efficient, with tri C16–18 methyl ammonium chloride was next. The alkyl trimethyl ammonium chlorides (particularly C12–14 trimethyl) performed well for the oxidation of benzyl alcohol to benzaldehyde with sodium hypochlorite. Trimethyl tallow, C16–18 partially unsaturated, ammonium chloride was the catalyst of choice for the dichlorocarbene addition to cyclohexene.  相似文献   

18.
Taking the results of methylene blue analysis as a yardstick for biodegradability, substituents in the benzene ring of linear alkylaryl sulfonates (CH3, C2H5, OH) greatly deteriorate the aerobic biodegradation characteristics of these products: adaptation time, amount of hard residue, and, to a lesser extent, rate of biodegradation. Replacement of one long alkyl chain by two short ones of the same total length also retards biodegradation. When the benzene ring is replaced by a thiophene ring, adaptation is improved.  相似文献   

19.
In this study, propylene glycol-based glycosides were obtained using an acetalization reaction in which glucose was first reacted with propylene glycol. Subsequently, the propylene glycol glycoside was reacted with alkyl glycidyl ether of varying carbon chain lengths (i.e., 08-G, 10-G, 12-G, 14-G, and 16-G) to synthesize a series of glucose-based biodegradable surfactants. The experimental results show that the surface activity of the C8–C12 glucose-based surfactants increases with the carbon chain length. However, the surface activity of the C14–C16 glucose-based surfactants decreased as the carbon chain length increased. Among all the surfactants, the C12 glucose-based surfactant exhibited the most efficient emulsification ability, lowest surface tension, lowest fluorescence intensity, highest zeta potential, and good emulsification stability. The glucose-based surfactants were used as additives in natural plant dyes made from turmeric or henna to dye wool fabrics. Higher color strengths were observed in the C14 glucose-based surfactant.  相似文献   

20.
Polystyrenes containing up to about 20 mol % sulfonic acid are reproducibly and readily prepared by the sulfonation of polystyrene at 50°C with acetyl sulfate in 1,2-dichloroethane solution. The metal salts of sulfonated polystyrene possess extremely high melt viscosities and are soluble in single solvents such as toluene and THF only at very low sulfonate levels. Such properties are the result of the very strong ion-dipole interactions among the metal sulfonate groups. Such strong interactions can be substantially reduced through the neutralization of the sulfonic acid with ammonia and, most especially, relatively simple low molecular weight amines. Sulfonated polystyrenes varying in sulfonic acid content from about 1 mol % to about 20 mol % were neutralized with various mono-, di-, and tri-substituted alkyl amines ranging in alkyl chain length from H (ammonia) to C20, and their rheological and thermal properties were measured. As the number of substituents on the nitrogen increased, the glass transition temperature and the melt viscosity decreased. The tributylamine sulfonates possessed viscosities almost as low as unsulfonated polystyrene and the longer chain amines behaved as if internally plasticized. The properties of amine neutralized sulfonated polystyrenes are concluded to be primarily a function of amine size. Increasing the size of the amine reduces the strength of the ion-dipole interaction by preventing close approach of the amine sulfonate groups.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号