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.     

Detergency and foaming properties of the system alkylarylsulfonate-soap-sodium carboxymethyl cellulose

Summary A study has been made of the detergency and foaming characteristics of a ternary system comprising a sodium alkylarylsulfonate, a medium titer soap derived from tallow and coconut oil, and sodium carboxymethyl cellulose under average conditions prevailing in household laundering. The carbon soil removal and whiteness retention properties of unbuilt soap are equalled or exceeded in compositions containing approximately five parts soap to one part alkylarylsulfonate, with a minor portion of CMC. Measurements made in a transparent cylindrical washer indicate that the decrease of foam height due to adsorption on fabric and hard water is much greater with soap than with alkylarylsulfonate. This results in greater foam volumes with alkylarylsulfonate than with soap at concentrations less than 0.2%, in water of hardness equivalent to 96–114 ppm. CaCO₃. Sodium carboxymethyl cellulose, when used with soap and alkylarylsulfonate in the proportions desirable for improvement of detergency, does not affect foaming properties significantly. When soap is the major ingredient in mixtures of soap and alkylarylsulfonate, foam height is critically dependent on concentration. When alkylarylsulfonate predominates, high foam levels are obtainable at low concentrations. The data reported permits selection of compositions from the ternary system for formulation with builders such that excellent detergency characteristics may be obtained under average conditions prevailing in household service, with high foaming characteristics as desired for agitator-type machines, or with moderate, controllable foaming for cylinder machines. Presented at the 43rd annual meeting, American Oil Chemists' Society, Houston, Tex., April 29, 1952.     

The solubility of sodium and potassium soaps and the phase diagrams of aqueous potassium soaps

Summary Solubility data are provided and collected for the pure sodium and potassium soaps. Hydrolysis obscures the temperatures of solution but is obviated by the presence of a small excess of alkali. Each sodium soap has a large range of temperature between fair and high solubility, whereas the potassium soaps go abruptly into solution, at almost the same temperature and concentration of each soap. The only soaps that are even moderately soluble at room temperature are potassium laurate, myristate, and oleate, the potassium salt of acids from coconut oil, and the sodium oleate. The other sodium and potassium soaps of the saturated fatty acids require elevated temperatures for solution. Phase diagrams for the five commonest potassium soaps are developed and recorded. This work was the basis of a thesis submitted in partial fulfillment of the requirements for the degree of Master of Science, Stanford University, 1947.     

Foaming properties of rosin soap and their comparison with those of fatty acid soaps

Summary The foam production of soaps made from rosin, modified rosins, and rosin acids were evaluated. The foam production of rosin soaps was compared with soaps made from the individual fatty acids. There was no difference in the foaming properties of soaps made from longleaf and slash pine rosin. Oxidation of the unstable rosin acids in rosin caused the foaming properties of the rosin soap to become more nearly proportional to the concentration. The more hydrogen present in the rosin acid molecule the greater were the foaming properties of the rosin soap. At temperatures between 200° C. and 275° C., the lower the temperature employed for producing pyroabietic acid catalytically, the greater were the foaming properties of the pyroabietic acid soap. There was a difference in the foaming properties of commercial stabilized rosins. In foaming properties the soaps made from rosins, modified rosins, and rosin acids were more like sodium laurate than the other individual fatty acid soaps tested. The author wishes to express his indebtedness to to Dr. G. S. Jamieson and W. G. Rose of the Agricultural Chemical Research Division for the pure lauric, myristic, palmitic and stearic acid used in this study.     

Tall oil fatty acids

About 1949, with the advent of effective fractional distillation, the tall oil industry came of age, and tall oil fatty acids (TOFA), generally any product containing 90% or more fatty acids and 10% or less of rosin, have grown in annual volume ever since, until they amount to 398.8 million pounds annual production in the U.S. in 1978. Crude tall oil is a byproduct of the Kraft process for producing wood pulp from pine wood. Crude tall oil is about 50% fatty acids and 40% rosin acids, the remainder unsaps and residues; actually, a national average recovery of about 1–2% of tall oil is obtained from wood. On a pulp basis, each ton of pulp affords 140–220 pounds black liquor soaps, which yields 70–110 pounds crude tall oil, yielding 30–50 pounds of TOFA. Separative and upgrading technology involves: (a) recovery of the tall oil; (b) acid refining; (c) fractionation of tall oil; and occasionally (d) conversion to derivatives. TOFA of good quality and color of Gardner 2 corresponds to above 97% fatty acids with the composition of 1.6% palmitic & stearic acid, 49.3% oleic acid, 45.1% linoleic acid, 1.1% miscellaneous acids, 1.2% rosin acids, and 1.7% unsaponifiables.     

表面活性剂复配体系的分析

介绍了一种使用经典的分析技术定量测定液体皂、皂胶、洗衣皂及香皂中存在的皂类、脂肪酸、非离子表面活性剂及除肥皂以外的阴离子表面活性剂和两性表面活性剂混合物的分析方法。这种方法克服了分析混合表面活性剂系统时常常会碰到的问题。     

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.     

The solubilization of calcium soaps by fatty acids

The solubilization of the calcium soaps of long chain fatty acids by liquid fatty acids was observed. The solubilities of calcium palmitate, calcium laurate, and calcium oleate were 15.6, 22.8, and 53.3 wt%, respectively, in oleic acid at 40°C. The formation of an acid-calcium soap complex was demonstrated by x-ray diffraction studies of calcium laurate, lauric acid, and a mixture of these compounds that had been heated. Similar evidence was obtained for a calcium oleate-oleic acid complex. The solubility of calcium oleate in a bile salt micellar system was enhanced by obeic acid. The solubilization of calcium soaps by liquid fatty acids may explain the unexpectedly high bioavailability of some calcium soaps.     

Fourier-transform infrared spectra of fatty acid salts—Kinetics of high-oleic sunflower oil saponification

Sodium, lithium, and calcium soaps obtained by saponification of high-oleic sunflower oil were studied by Fourier-transform infrared spectroscopy. Spectra of crude mixtures containing soap, glycerin, residual alkali, and triacylglycerols were compared to those of pure soaps obtained from fatty acids. The infrared spectra of crude soaps showed the same characteristic bands as pure ones. The absorption bands of asymmetric (ω₂) and symmetric (ω₁) stretching vibrations of the carboxylate group indicated that the metal-oxygen bonds of these soaps had an ionic character whose strength differed from one cationic counterion to another. Once the characteristic absorption bands of the soaps were assigned, a kinetics study of saponification was performed. Saponification by sodium, anhydrous lithium, and calcium hydroxides was an autocatalytic reaction, characterized by an S-shaped kinetics curve, whereas saponification by aqueous lithium hydroxide was stoichiometric. The structure of the metal-oxygen bond played a role in the kinetic mechanisms.     

The separation of solid fatty acids from liquid fatty acids by the formation of acid soaps. I. Tallow soaps

The formation of acid soaps has been used successfully for the separation of a mixture of fatty acids into high and low iodine value fractions. The acid soaps of saturated acid can be made to crystallize from water leaving their unsaturated counter parts in solution. Acid soaps of saturated fatty acids are well characterized compounds with the formula R-COOM.R-COOH, where R is a straight alkyl chain, and M is sodium, potassium or ammonium. Optimum crystallization conditions involve a soap concentration of 2–5%, pH adjustment to between 7.0 and 8.0, an initial crystallization temperature not below 25C, and a crystallization period of at least 4 hr during which time cooling to a final temperature of 5–10C must be gradual, and agitation gentle.     

Chemical and physical characteristics of soap made from distilled fatty acids of palm oil and palm kernel oil

Manufacture of soaps from distilled fatty acids of palm oil (PO) and palm kernel oil (PK) is a well-established technology in Malaysia. Data on quality and characteristics of various blends of PO/PK fatty acid-based (palm-based) soaps made in Malaysia are not available, however. In view of this, the study described in this paper was undertaken. Eleven blends of palm-based bar soaps were made, and their properties were evaluated. There was an increase in the acid value of blended raw materials with increasing amounts of PK fatty acids. The iodine value and titer (°C) of blended raw materials, however, bear an inverse relationship with the amount of PK fatty acids. As expected, the hardness of the soap bars from the various blends increased with increasing PK fatty acid. Total fatty matter ranged from 76–85%, free caustic content was 0.1%, and sodium chloride content was 0.3–0.4%. Characteristics of soap blends made for this study were comparable with those from other countries. Quality of the soap obtained was comparable to those produced commercially.     

Preparation and surface-active properties of the sodium soaps,mono- and diethanolamides and diol and triol sulfates of cycloaliphatic C21 Di- and C22 Tricarboxylic acids

Cycloaliphatic C₂₁ di- and C₂₂ tricarboxylic acids were prepared by the Diels-Alder reaction of dehydrated castor oil (DCO) fatty acids (containing 48% conjugated and 42% nonconjugated dienes) with acrylic and fumaric acids, respectively. The reaction temperature, time, catalyst concentration, and mole ratio of reactants were varied to get maximum yields of the di- and tricarboxylic acids. The unreacted DCO fatty acids were removed from the products by partition between aqueous methanol and n-hexane. The products were converted to methyl esters and characterized as the substituted cyclohexene derivatives before and after dehydrogenation with Pd/C in xylene, hydrogenation with Pd/C in decalin and oxidation with periodate-permanganate reagent and by mass and proton nuclear magnetic resonance spectrometry. The acids were converted to sodium soaps, mono- and diethanolamides and the corresponding diol and triol sulfates, and the resulting products were evaluated for their surface-active properties. The sodium soaps showed better calcium tolerance and poorer foaming power than sodium oleate. The diethanolamides were inferior to lauroyl diethanolamide in wetting and emulsifying power. The monoethanolamides were better than the respective diethanolamides and lauroyl diethanolamide in wetting property. The diol and triol sulfates were poorer in wetting and emulsifying ability and better in calcium tolerance than sodium lauryl sulfate.     

Solubility of calcium soaps of gum rosin,rosin acids and fatty acids

Summary The solubility of calcium soaps of rosin acids and fatty acids have been determined and compared. The solubility of calcium soaps of rosin acids (d-pimaric, dihydroabietic, and l-abietic acids) present in gum rosin was found to be greater than that of the calcium soaps of the following saturated fatty acids: lauric, myristic, palmitic, and stearic acids. The calcium oleate was much more soluble than the calcium stearate. As the amount of hydrogen in the rosin acid molecule is increased, l-abietic to dihydroabietic to tetrahydroabietic acid, the solubility of the calcium soap is decreased. The author wishes to express his indebtedness to Dr. G. S. Jamieson and W. G. Rose of the Agricultural Chemical Research Division for the pure lauric, myristic, palmitic and stearic acid used in this study.     

9,10,12,13-四羟基硬脂酸钠在低温硬质水及中性pH条件下的特异性能

以天然亚油酸为原料,经氧化水解制备得到9,10,12,13-四羟基硬脂酸(THSA),采用FTIR、ESI-MS和1HNMR表征了THSA的结构。测定了THSA的钠皂9,10,12,13-四羟基硬脂酸钠(STHS)的克拉夫特点、钙离子稳定性、钙皂分散剂消耗量、表面张力、临界胶束浓度和泡沫性能,并与对照物亚油酸、油酸及硬脂酸的钠皂进行比较。结果表明,STHS具有其他脂肪酸钠皂不具备的优秀钙皂分散性能和钙离子稳定性,并在低温和中性条件下显示出更好的水溶性。STHS不仅克服了普通脂肪酸钠皂不耐硬水和中性条件下溶解性差两大共同缺陷,也克服了饱和脂肪酸钠皂低温溶解性差以及不饱和脂肪酸钠皂易氧化酸败的缺点,因此,STHS具有在中性皂、低温皂和抗硬水皂配方中用作新皂基表面活性剂的潜质。     

Rosin/acid oil-based liquid soap

Soapstock was converted into a liquid soap from its acid oil and formulated with varying amounts of rosin. The characteristics of the acid oil and rosin were experimentally estimated. Liquid soaps were characterized by density, pH, total fatty matter, free caustic alkali, critical micelle concentration, foaming capacity, wetting power, and washing performance. The foaming results indicated that the liquid soap is best used as an ingredient in a washing-machine detergent. The dark aspect of a formulation with 10% rosin precluded higher substitution.     

Long chain alkanesulfonates and 1-hydroxy-2-alkanesulfonates: Structure and property relations

Even chain sodium alkanesulfonates from the Strecker reaction, odd chain sodium alkanesulfonates from the alkaline decarboxylation of α-sulfo acids, and sodium 1-hydroxy-2-alkanesulfonates from the reduction of esters of α-sulfo acids were compared with respect to Krafft point, critical micelle concentration, detergency and foam height. Sodium alkanesulfonates and crude fusion products from the α-sulfo acids (mixtures of alkanesulfonates of one less carbon atom with a lesser amount of a soap of two less carbon atoms) are more soluble and have better detergent and foaming properties. Sodium 1-hydroxy-2-alkanesulfonates resemble monosodium salts of α-sulfo acids. Alkanesulfonic acids and 1-hydroxy-2-alkane-sulfonic acids obtained from the sodium salts by ion exchange have lower Krafft points and are more readily soluble. The critical micelle concentrations of 1-hydroxy-2-alkanesulfonic acids and α-sulfo acids are nearly the same and about equal to those of alkanesulfonic acids of one less carbon atom. Presented at the AOCS meeting in Toronto, Canada, 1962. A laboratory of the E. Utiliz. Res. & Dev. Div., ARS, U.S.D.A.     

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.     

Krafft Temperature,Critical Micelle Concentration,and Rheology of “Pseudo-Gemini” Surfactant Comprising Fatty Acid Soap and Bola-Type Quaternary Ammonium Salt

Bola-type quaternary ammonium salt can bridge with two fatty acid soaps through electrostatic attraction to form a pseudogemini surfactant, which enhances the solution viscosity. In this work, the effects of the building blocks (spacer and hydrophobic chain) of a pseudogemini surfactant on the Krafft temperature, critical micelle concentration, and rheological properties were investigated. The results revealed that the addition of bola-type salt obviously decreased the Krafft temperature of sodium stearate (C₁₈ONa), and a bola-type salt bearing a large benzene ring (Bola2be) was more effective than the one bearing an ethyl group (Bola2et) or a hydroxyethyl group (Bola2hy). When bola-type salt is mixed with fatty acid soap at a fixed molar ratio of 1:2, a pseudogemini surfactant forms in situ, and the viscosity of the solution is significantly enhanced by the formation of a worm-like micelle (WLM) network. The stronger the hydrophobicity of the bola-type salt or the tail of the fatty acid soap, the lower the critical overlapping and micelle concentrations, and the stronger is the ability to enhance viscosity. However, pseudogemini surfactants that use sodium stearate as a monomer show similar self-assembly abilities to those using sodium oleate as a monomer. In addition, the WLM formed by pseudogemini surfactants composed of Bola2be and sodium stearate or sodium oleate were liable to branch at high concentrations.     

Studies in soap crystallization processes. Part III. Acid soap crystallization in the segregation of tall oil fatty acids

Tall oil fatty acids have been fractionated into 80–90% oleic acid, and 60–80% linoleic acid fractions, by precipitation of the oleic acid as acid soap from polar solvents. Sodium and potassium acid soaps are equally effective, but ammonium acid soaps require lower operating temperatures. The choice of solvent is not critical as regards degree of separation, but technically attractive filtration rates have been obtained only with methanol and acetone. Acidulation gives colorless oleic acid of very low rosin acid and unsaponifiable content, but with 5–10% of conjugated linoleic acid.     

Properties of soaps derived from distilled palm stearin and palm kernel fatty acids

Soaps made from blends of distilled palm stearin (PS) and palm (PK) kernel fatty acids were evaluated for total fatty matter, sodium chloride content, moisture content, hardness, Hunter whiteness, foamability, iodine value, titer value, and acid value. Data showed that these soaps had properties similar to palm-based soaps made from distilled palm oil and palm kernel fatty acids. The soaps showed good whiteness (greater than 80%) and foamability. Total fatty matter ranged from 10–18%, sodium chloride content was 0.5%, and free caustic was 0.1% except for blend 8 containing 10 PS:90 PK, which had a free caustic of 0.03%. Initial penetration value, a reflection of soap hardness, ranged from 32–126 mm, with an average value of 54 mm. This value is within the range of the best blends of palm-based soaps (50–63 mm). There was no obvious trend observed. Penetration value, however was found to stabilize after a month of storage with an average value of 19.4 mm. Soap with this hardness value is relatively hard and therefore should be blended with a small amount of soft oils.