Araki Masuyama

Preparation and surface active properties of amphipathic compounds with two sulfate groups and two lipophilic alkyl chains

These compounds with various connecting groups between the two lipophilic groups were prepared by the reaction of glycol diglycidyl ethers with long-chain alcohols, followed by sulfation with chlorosulfonic acid or with a mixture of chlorosulfonic acid and acetic acid. The Krafft point of all these new amphipathic compounds was below 0°C, and they had good water solubility. These compounds were superior in surface active properties to general anionic surfactants with one lipophilic chain and one hydrophilic group, such as sodium dodecylsulfate. The effect of the structure of the connecting group on CMC, γCMC, foaming properties and wetting ability was investigated. They also showed excellent lime-soap dispersing ability.

Preparation and properties of glycerol-based double- or triple-chain surfactants with two hydrophilic ionic groups

A novel series of glycerol-based double- or triple-chain surfactants with two sulfonate, two sulfate or two carboxylate groups was conveniently prepared by reactions of 1-O-alkylglycerol diglycidyl ethers with long-chain fatty alcohols, and followed by reactions with propanesultone, chlorosulfonic acid or bromoacetic acid, respectively. The sulfate and carboxylate types of compounds have higher water solubilities than the corresponding sulfonate type of compound bearing the same lipophilic group. The triple-chain surfactants show excellent surface-active properties, such as micelle forming and ability to lower surface tension, compared not only with the corresponding single-chain anionic surfactants, but also with the corresponding double-chain surfactants. The effect of the difference in head groups of these compounds on surface-active properties is described. Foaming properties, wetting ability and lime-soap dispersing requirement are also discussed.

Synergism in binary mixtures of surfactants 12. Mixtures containing surfactants with two hydrophilic and two or three hydrophobic groups

Abstract Molecular interactions between several anionic sulfonate surfactants containing two hydrophilic groups and two or three hydrophobic groups in the molecule (gemini surfactants) and a zwitterionic surfactant (N,N-dimethyl-1-tetradecanamine oxide) or a polyoxyethylenated non-ionic surfactant (C12H25(OC2H4)7OH or C12H25(OC2H4)8OH) were measured at 25°C in aqueous 0.1 M NaCl solution. The strength of the interaction with the zwitterionic surfactant decreases with increase in the minimum area per sulfonate group of the gemini surfactant at the air/water interface. The interaction with the zwitterionic surfactant or the polyoxyethylenated non-ionic surfactant is also weakened by the presence of multiple ether linkages in the hydrophilic group of the gemini surfactant. The latter surfactants with these linkages show a smaller increase, compared with gemini surfactants without them, in their interaction with the zwitterionic surfactant upon reduction of the pH of the solution. They also show an increase with this change in their area per molecule at the air/water interface and an increase in their interaction with an alkanesulfonate surfactant (C12H25SO3Na), increases not shown when neither surfactant has multiple ether linkages in the molecule. It is suggested that the relative ease of protonation of the multiple ether oxygen atoms in the doubly charged anionic gemini molecule accounts for these observations. The interaction in mixed micelles is much weaker than in mixed monolayers at the air/water interface; this is attributed to the difficulty of incorporating a surfactant with multiple hydrophobic groups into a micelle. The compounds studied all show synergism in surface tension reduction efficiency and effectiveness when mixed with the amine oxides, consistent with the synergism parameters. They also show synergism in mixed micelle formation with the amine oxide, except for a compound with three alkyl chains and one with a trioxyethylene group in the hydrophilic part. This is attributed to steric inhibition of micelle formation. As a result of protonation, the anionic gemini surfactants with multiple ether oxygen atoms in the molecule show little or no synergism when mixed with a polyoxyethylenated non-ionic surfactant. Synergism in the surface tension reduction effectiveness for these compounds when mixed with an alkanesulfonate at a low pH, however, is indicated.

Preparation and surface- active properties of new amphipathic compounds with two phosphate groups and two long- chain alkyl groups

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.

Preparation, surface-active properties and acid decomposition profiles of a new “soap” bearing a 1,3-dioxolane ring

New soap-type surfactants bearing a 1,3-dioxolane ring were prepared in good yields by the acid-catalyzed condensation of 1-O-alkylglycerols (alkyl: decyl, dodecyl, tetradecyl, heptadecyl, octadecyl, orcis-9-octadecenyl) with oxocarboxylic acid esters, followed by alkaline hydrolysis without any expensive reagent and special equipment. These surfactants were soluble in alkaline water at room temperature. Their critical micelle concentrations were much smaller than that of sodium dodecanoate. An alkaline solution of the octadecyl homologue was nonfoaming, but the other homologues, including thecis-9-octadecenyl derivative, showed high foaming ability in alkaline solutions. The structural effect of these compounds on the area per molecule at the surface is also discussed. Because these surfactants contain a 1,3-dioxolane ring, they can be utilized as a new acid-decomposable type of cleavable surfactant. At pH 1, they decompose almost completely into nonsurface-active species after 80 min.

Synthesis, crystal structure and anti-malarial activity of novel spiro-1,2,4,5-tetraoxacycloalkanes

(Cycloalkylidene)bishydroperoxides 3 react with 1,n-dihaloalkanes (n = 3–6) in the presence of CsOHH 2 O in DMF affording the corresponding spiro-1,2,4,5-tetraoxacycloalkanes 4 in moderate yields. Compound 4ba exhibits significant antimalarial activity in vitro against P. falciparum .

Preparation and properties of double- or triple- chain surfactants with two sulfonate groups derived fromN- Acyldiethanolamines

Bis(sulfonate) types of amphipathic compounds with three long- chain alkyl groups were prepared by the reaction ofN- (long- chain acyl)diethanolamine diglycidyl ethers with long- chain fatty alcohols, followed by the reaction with propanesultone. The diglycidyl ethers were easily obtained from the correspondingN- acyldiethanolamines and epichlorohydrin in the presence of a phasetransfer catalyst. The same types of compounds with two longchain alkyl groups were also prepared from Nacetyldiethanolamine according to similar procedures. All these new double- or triple- chain surfactants were soluble in water and showed much better micelle forming and ability to lower surface tension than general types of single- chain surfactants with one sulfonate group. The critical micelle concentration (CMC) and γCMC values of the triple- chain compounds were still much smaller than those of the corresponding double- chain compounds with two common alkyl groups. The efficiency of adsorption at the water/air interface (pC20) of these surfactants was very high. Their foaming properties, wetting ability toward a felt chip, and lime- soap dispersing ability were measured.

Complexing ability of N-oligoethylene glycol monoaza crown ethers with sodium and potassium cations

Abstract N-Oligoethylene glycol monoaza crown ethers were prepared, and the notable effect of oxyethylene oxygen atoms of the side chain on complexing ability with sodium and potassium cations was confirmed.

New cleavable surfactants derived from glucono-1,5-lactone

New amido nonionic cleavable surfactants were synthesized in good yields by the acetalization of glucono-1,5-lactone with octanal, 2-octanone or 2-undecanone, followed by amidation with monoethanolamine, diethanolamine or morpholine. These compounds possessed good water solubilities. The compounds derived from 2-octanone showed higher critical micelle concentrations than the compounds from octanal. For the same hydrophobic chain, both the micelle-forming property and the ability to lower surface tension increased with the change in the terminal amide group in the order diethanolamide<morpholide<monoethanolamide. Interestingly, in spite of their relatively short hydrophobic chains, these compounds showed greater ability to lower surface tension than conventional nonionic surfactants, such as alcohol ethoxylates. Furthermore, their acid-decomposition properties were determined. Their decomposition rates were also compared with that of the corresponding carboxylate type of compound derived from glucono-1,5-lactone.

Double-chain surfactant as a new and useful micelle-forming reagent for micellar electrokinetic chromatography

Abstract Disodium 5,12-bis(dodecyloxymethyl)-4,7,10,13-tetraoxa-1,16-hexadecanedisulphonate, a surfactant with two ionic groups and two lipophilic chains, was f