Detergent action of rosin soaps and fatty acid — Rosin soaps

Summary A method for evaluating the detergent action of soaps has been described and applied to a series of soap solutions. The detergent action of rosin soaps, the effect of compounds present in soap or used with soap on the detergent action of a rosin soap, and the effect of rosin soap on the detergent action of tallow soap have been tested. The effect of temperature on the detergent action of some of the detergent solutions has also been determined. The results of these detergent tests on rosin, fatty acid and fatty acid-rosin soaps indicated the following: (1) Rosin soaps made from different gum rosins, produced from longleaf and slash pine gums, have equal detergent action; (2) The presence of soaps of oxidized rosin acids has no effect on detergent action of the rosin soap; (3) The detergent action of soaps made from pyroabietic acid, abietic acid and hydrogenated rosin parallels their ability to lower the surface tension of water and the amount of hydrogen present in the rosin acids; (4) The addition of builders that increase the alkalinity of the rosin soap solution improves the detergent action of the solution; (5) The blending of rosin soap with tallow soap improves the detergent action of the tallow soap in solutions having a soap concentration of 0.25 percent or more; (6) Temperature affects the detergent action of rosin and coconut oil soaps more than tallow soap.     

C-21 dicarboxylic acids in soap and detergent applications

A unique polycarboxylic acid, 5(6)-carboxy-4-hexyl-2-cyclohexene-1-octanoic acid, has been available commercially for over 15 years. A new high-purity (>97%), light-color version of the C-21 dicarboxylic acid has been developed recently. Soaps of the C-21 dicarboxylic acid can be used as hydrotropes to increase the solubility of nonionic surfactants in aqueous solutions containing builders and/or anionic surfactants. Since these soaps are anionic fatty acid derivatives, they reduce the surface tensions of formulations, thus improving detergency. The nontoxic and biodegradable nature of this dicarboxylic acid makes it an attractive formulation component. This paper outlines application evaluations of the soaps prepared from the C-21 dicarboxylic acids. These evaluations demonstrate how the soaps interact with nonionic surfactants or pine oil to provide clear formulations, how they wet cotton skeins in neutral to highly alkaline solutions, and how they inhibit gel formation when preparing high-solids fatty acid soap solutions. Furthermore, the preparation and characterization of the soaps of the C-21 dicarboxylic acid products are discussed. Mass-balance equations describe the preparation of aqueous soap solutions at any given concentration. Characterization of the resulting soap solutions includes acid number, pH, color, color stability, foam stability, surface tension as a function of concentration, and hard-water compatibility.     

Perfectly Wetting Mixtures of Surfactants from Renewable Resources: The Interaction and Synergistic Effects on Adsorption and Micellization

This paper presents a study of the surface properties of mixtures of surfactants originating from renewable sources, i.e., alkylpolyglucoside (APG), ethoxylated fatty alcohol (AE), and sodium soap (Na soap). The main objective was to optimize the surfactant ratio which produces the highest wetting properties during the analysis of the solution of the individual surfactants, two- and three-component mixtures, and at different pH values. The results showed the existence of a synergistic effect in lowering the interfacial tension, critical micelle concentration and the formation of mixed micelles in selected solutions. We found that best wetting properties were measured for the binary AE:APG mixtures. It has been demonstrated that slightly lower contact angles values were observed on Teflon and glass surfaces for the AE:APG:soap mixtures but the results were obtained for higher concentration of the components. In addition, all studied solutions have very good surface properties in acidic, basic and neural media. However, the AE:soap (molar ratio of 1:2), AE:APG (2:1) and AE:APG:soap (1:1:1) compositions improved their wetting power at pH 7 on the aluminium and glass surfaces, as compared to solutions at other pH values tested (selected Θ values close to zero—perfectly wetting liquids). All described effects detected would allow less surfactant to be used to achieve the maximum capacity of washing, wetting or solubilizing while minimizing costs and demonstrating environmental care.     

Determination of Critical Micelle Concentration of copper soaps in non-aqueous solvents

The critical micelle concentration (C.M.C.) for copper soaps has been determined from studies of density, viscosity and surface tension of non-aqueous solutions of copper soaps. The C.M.C. values depend on the nature of the solvent and the values are higher in alcohols than in hydrocarbons. The plots of density, viscosity, specific viscosity and surface tension against the soap concentration are characterised by an intersection of two straight lines at a definite soap concentration which corresponds to the C.M.C. of the soaps.     

Studies on surface tension and parachor of copper soap solutions in nonaqueous solvents

Colloid chemical behavior of copper soaps in nonaqueous solvents has been investigated from the surface tension results using Szyszkowski's empirical equation:γ=γ _o (1 + Xln Y) - X γ _o lnC. The parachors of the soap solutions in hydrocarbons are independent of the soap concentration. However, in alcohols these values increase with the increase of soap concentration. Hammic and Andrew's mixture law equation has been successfully applied to explain the behavior in alcoholic soap solutions.     

Physical-chemical properties of tall-oil soap solutions

Summary Acid-refined tall-oil was separated into resin acid and fatty acids of approximately 94% purity, made into soaps, and compared with those made from oleic acid and rosin. Tall-oil resin-acid soap and rosin soap are roughly comparable in dispersing power and lowering of surface tension and interfacial tension. The tall-oil fatty-acid soap shows some points of inferiority to sodium oleate, as might reasonably be expected because of its greater unsaturation. Presented at 113th meeting of the American Chemical Society, Chicago, Ill., April 14–23, 1948.     

Studies in detergency correlation

In alkaline cleaning solutions of ca. pH 12 containing either a primary alcohol sulphate, a straight chain alkyl aryl sulphonate, or a fatty acid soap, detergent efficiency is increased synergistically by the addition of nonionic agents the HLB values of which lie within certain ranges. Those cleaners containing the anionic surfactant with the highest HLB exhibit the most synergism. In such cleaners, increasing detergency is directly related to increasing surface tension and critical micelle concentration of the unbuilt anionic surfactant, and to increasing surface tension of the nonionic surfactant. Asphalt soil removal, judged the resultant of the combined properties of penetrability, peptization, and wetting, was used to indicate detergent synergism in the aqueous alkaline cleaners studied.     

Biological behavior of some soap-based detergents

The biodegradability of tallow soap, three soap-based detergent formulations and their component lime soap dispersing agents—sodium methyl α-sulfotallowate, sulfated N-(2-hydroxypropyl) tallowamide, and sodium N-methyl N-(2-sulfoethyl) tallowamide—was determined under aerobic and microaerophilic conditions. Both sewage and river water microorganisms were used as the sources of inoculum. The course of biodegradation was followed by loss of carbon and methylene blue active substance, and by increase in turbidity and surface tension. Carbon analysis for soap in solutions containing Ca⁺⁺ and Mg⁺⁺, which would precipitate soap, was performed by an improved technique using the disodium salt of ethylenediamine tetraacetic acid. Invariably a decrease in carbon content was accompanied by an increase in turbidity and surface tension. Also, loss in methylene blue active substance was concurrent with an increase in turbidity and surface tension of the degrading solutions of the detergent. Soap cannot be determined as methylene blue active substance because of the low pH of the test. Soap and the built soap formulations degraded under aerobic and microaerophilic conditions. Preliminary toxicity data upon mammals and fish indicated that the soap-based detergents are as safe as conventional commercial detergents. ARS, USDA.     

New amphoteric surfactants containing a 2-hydroxyalkyl group: IV. Performance of amphoteric surfactant/soap blends

The performance of new amphoteric surfactants,N-(2-hydroxyethyl)-N-(2-hydroxyalkyl)-β-alanines (HAA) and their oxyethylated derivatives (HAA-nEO) was studied in blends with a fatty acid soap. The solubility, foaming power and fabric detergency were measured for blends of (Na-HAA or Na-HAA-nEO)/soap. Furthermore, lime soap dispersing power, toxicity to fish and biodegradability for HAA or HAA-nEO homologs were examined and evaluated. The blend of tallow soap and not less than 10% of C_12–14-Na-HAA exhibited better solubility behavior than tallow soap or tallow/coconut oil soap alone. Fabric detergency was improved by blending Na-HAA with soap. Soil deposition in Na-HAA/soap or Na-HAA/soap/Na₂CO₃ solution was measured. On the basis of the results for: (a) the measurements of redeposition; (b) interfacial tension between oil and water and (c) contact angle between oil and fabric in water, it was presumed that since Na-HAA adsorbed more or less in preference to soap on the surface of fabric in water, soil redeposition would be prevented in the Na-HAA/soap detergent solution.     

聚甘油脂肪酸酯的表面性能研究

利用甘油聚合得到聚甘油,与一系列高级脂肪酸酯化合成聚甘油脂肪酸酯。分别测试和比较了合成产品的HLB值、表面张力、乳化性能、泡沫性能及钙皂分散性能,并讨论了合成影响因素,为研究聚甘油酯类产品应用性能提供了理论基础。     

Contact angle of surfactant solutions on precipitated surfactant surfaces. II. Effects of surfactant structure,presence of a subsaturated surfactant,pH, and counterion/surfactant ratio

The contact angle of a saturated aqueous surfactant solution on the precipitate of that surfactant was measured by using the sessile drop method. The sodium and calcium salts of alkyl sulfates (C₁₂, C₁₄, and C₁₈) had advancing contact angles higher than those of alkyl trimethylammonium bromides (C₁₄, C₁₆, and C₁₈). The measured advancing contact angles for several surfactant solutions did not substantially change with varying surfactant/counterion ratios; therefore, the precipitating counterion concentration (e.g., water hardness) had little effect on the wettability. The contact angles of fatty acid (C₁₂ and C₁₆) solutions did not show any dependence on pH between a pH of 4 and 10. The contact angles of saturated calcium dodecanoate (CaC₁₂) solutions containing a second subsaturated surfactant (sodium dodecyl sulfate: NaDS) decreased with increasing NaDS concentrations until reaching the critical micelle concentration of the surfactant mixture. These results show that the second suractant can act as a wetting agent in this saturated surfactant system. Application of Young’s equation to contact angles showed that the solid/liquid surface tension can change substantially with surfactant concentration and be important in addition to the liquid/vapor surface tension in reducing contact angles. Application of the Zisman equation results in a “critical” surface tension for the CaC₁₂ or soap scum of 25.5 mN/m, which is comparable to difluoroethene.     

十二烷基苄醇聚氧乙烯醚的合成及性能

以十二烷基苯为原料,经氯甲基化、水解及环氧乙基化等步骤得到平均乙氧基(EO)数为9.5的十二烷基苄醇聚氧乙烯醚(LBAEOn)。分别用FTIR和1HNMR表征了产物LBAEOn的结构特征,并用ESI-MS确定了LBAEOn中的EO分布。以表面张力法测得在25℃时LBAEOn的cmc和γcmc分别为1.83×10-6mol.L-1和39.0 mN.m-1;与脂肪醇聚氧乙烯醚(AEO9)和壬基酚聚氧乙烯醚(NPEO10)相比较,除钙皂分散性能大致相当以外,LBAEOn的表面活性较好、发泡力较低、对正辛醇的增溶能力较强和对帆布的润湿性能较差。     

Surface active properties of combinations of soap and lime soap dispersing agents

Surface tension versus log concentration curves were obtained for combinations of a variety of lime soap dispersing agents (LSDA) with sodium oleate. Salient features of the curves for these mixtures were: (a) criticial micelle concentration (CMC) close to that for LSDA alone; (b) absence of a surface tension minimum or substantial reduction in the minimum, which was often found with LSDA alone; (c) surface tension values above the CMC very close to those found for soap alone above its CMC; and (d) slope below the CMC greater than that for soap alone, more like that for soap with alkali added or lime soap dispersing agent alone. Higher CMC values were confirmed by dye solubilization measurements. The surface tension curves provided further evidence for the mixed micellar nature of soap-LSDA mixtures and suggested that the addition of LSDA to soap increased the surface concentration of surfactant. Presented at the AOCS Meeting, Chicago, September 1976.     

皂膜解吸Marangoni对流观察及分析

利用竖直流动皂膜装置,使用纹影光学方法观察了由于丙酮从皂液中解吸,在微米级厚度皂膜上出现的滚筒状Marangoni对流结构;通过建立皂膜传质数学模型及求解,分析了丙酮从皂膜解吸过程中浓度及表面张力的变化。结果表明:由于微米级的皂膜厚度,在皂膜平面法向方向皂膜内皂液丙酮浓度变化很小,但浓度梯度较大,对应的表面张力梯度较大,此较大表面张力梯度是丙酮从皂膜解吸过程中出现Marangoni对流的主要成因。     

Contact angle of surfactant solutions on precipitated surfactant surfaces. III. Effects of subsaturated anionic and nonionic surfactants and NaCl

The contact angles of saturated calcium dodecanoate (CaC₁₂) solutions containing a second subsaturated surfactant on a precipitated CaC₁₂ surface were measured by using the drop shape analysis technique. The subsaturated surfactants used were anionic sodium dodecylsulfate (NaDS), anionic sodium octanoate (NaC₈), and nonionic nonylphenol polyethoxylate (NPE). Comparing at the critical micelle concentration (CMC) for each surfactant, NaC₈ was the best wetting agent, followed by NaDS, with NPE as the poorest wetter (contact angles of 32⁰, 42⁰, and 62⁰, respectively). Surface tension at the CMC increased in the order NaC₈<NPE<NaDS, and subsaturated surfactant adsorption increased in the order NPE≪NaDS (1.4 vs. 84 μmole/g); adsorption of the NaC₈ was not measurable. Interfacial tension (IFT) reduction at the solid-liquid interface due to subsaturated surfactant adsorption is an important contribution to contact angle reduction, in addition to surface tension reduction at the air-water interface. Surfactant adsorption onto the soap scum solid is crucial to solid-liquid IFT reduction and to good wetting. The fatty acid was the best wetting agent of the three surfactants studied, probably because calcium bridging with the carboxylate group synergizes surfactant adsorption onto the solid of the higher molecular weight soap. NaCl added to NaDS surfactant results in depressed CMC, lower surface tension at the CMC, decreased NaDS adsorption onto the solid, and decreased reduction in solid-liquid IFT. The contact angle is not dependent on the NaCl concentration for NaDS. The NaCl causes an increased tendency to form monolayers, which decrease air-water surface tension, but a decreased tendency to form adsorbed aggregates on the solid; the two trends offset each other, so wettability is not affected by added salt. The Zisman equation does not describe the wetting data for these systems well except for NaDS, further emphasizing the danger of ignoring solid-liquid IFT reduction in interpreting wetting data in these systems.     

Physical properties of blends of soap and lime soap dispersants

The mechanism of action of soap lime-soap dispersant (LSDA) combinations is based on a close association between these two components. In deionized water this association is mixed micellar. Surface tension curves confirm the presence of mixed micelles in deionized water and show a combination of optimum surface active properties (low critical micelle concentrations (CMC), high surface concentration and low surface tension above the CMC). Solubilization of high Krafft point soap by LSDA and of difficultly soluble LSDA by soap are related results of this association. Analysis of dispersions of mixtures of soap and LSDA in hard water shows that the dispersed particles are mixtures of soap and LSDA in the same proportion as they were originally added. These findings are inconsistent with the view that soap reacts separately with hard water ions and that the resulting lime soap is suspended by surface adsorption of LSDA. The suspended particles are responsible for surface active properties and detergency and do not permit deposits on the fabric like those found with soap alone.     

竖直流动皂膜中解吸导致的Marangoni对流观察

In gas-liquid mass transfer processes,Marangoni convection may occur due to the surface tension gradient produced by mass transfer near the interface.With a falling soap film tunnel and the Schlieren optical method,the Marangoni convection patterns along the film surface were observed directly in the desorption process of acetone from the falling soap film.The Schlieren images showed the regular roll convection in the thin falling soap film during the acetone desorption.The hydraulic characteristics were determined experimentally by measuring the variation of acetone concentration in the film and the surface tension of the soap liquid.The results show that the acetone concentration gradient vertical to the falling direction is very small because the thickness of the soap film is in the order of 10^-6 m.The variation of acetone concentration along the falling film is large,so there is a significant surface tension gradient,resulting in the Marangoni roll convection.The experimental results and a qualitative analysis may be helpful to understand the mechanism of Marangoni convection near the interface in the mass transfer.     

Studies on surface tension of the system: Barium soap-water and propanol-1

The surface tension results of the barium soap solutions in water-propanol-1 mixtures have been explained on the basis of Szyszkowski’s empirical equation:γ =γ _o (1 + X ln Y) - Xγ _o ln C. The values of the constants X and Y of the equation have been calculated for various soap systems. The constant X is found to be almost independent of the composition of the solvent mixture but it depends to some extent on the chain length of the soap. The values of Y show a marked increase at 50% propanol-1 concentration which confirms that the transition in the nature of the micelles takes place at about 50% propanol-1 concentration. The values of X and Y are suggestive of the size and nature of the micelles, respectively.     

A novel sample preparation for chloride analysis in bar soaps

A simple and rapid sample preparation technique is described for the potentiometric determination of chloride in bar soaps. Usual preparation of soap for potentiometric chloride analysis involves time-consuming dissolution of the sample in water or heating to affect dissolution, followed by a cooling step. Also, when performing potentiometric titrations for chloride under the usual acid conditions, aqueous solutions of soap bars (unlike combination soap/detergent bars) will form insoluble semisolid fatty acids that can occlude some chloride and make clean-up difficult. This paper describes a simple dissolution of bar soap sample in dilute H₂SO₄/methanol at ambient temperature that simultaneously acidifies the sample solution and produces noninterfering methyl esters from the soap fatty acids; water is then added, and the chloride is determined potentiometrically with standardized AgNO₃. This procedure has been shown to work well with automatic titrators.     

Methyl glucoside fatty acid diesters

Summary and Conclusion Procedures are described for the preparation of methyl glucoside diesters by direct esterification, using a ratio of one mole of methyl glucoside with two moles of fatty acids. Rate studies indicated that lead or stannous soaps are more effective catalysts than the sodium soaps for speeding up tis esterification. With equal molar quantities of methyl glucoside and fatty acid, the lead and the sodium soap catalysts give products containing predominantly diester and half the methyl glucoside remaining unreacted. Under the same conditions stannous soap catalysis gives high yields of monoesters containing only very small percentages of unreacted methyl glucoside. From the standpoint of speed of reaction, color of the final produets, ease of removal of catalyst from the ester products, and catalyst cost, litharge is the preferred cytalyst for the preparation of methyl glucoside diesters. Properties of various methyl glucoside fatty acid diesters, prepared on a laboratory scale, are given. Du Noüy surface-tension measurements indicate that small quantities of the methyl glucoside dilaurate, dicaprate, or dioleate are quite effective in lowering the surface tension of water.