Ehthylene oxide (EO) cannot react directly with fatty methyl esters that have no active hydrogen. We developed a new synthetic method, which directly inserts EO into fatty methyl esters (RCOOCH 3) to give [RCO(OCH2CH2)nOCH3]. This was achieved by the use of a novel solid catalyst modified by metal cations. Ethoxylates of fatty methyl esters obtained by this method were homogeneous monoesters and had good properties as nonionic surfactants. JAOCS 72, 781-784 (1995). KEY WORDS:Acid-base bifunctional catalyst, coordination anionic polymerization, detergency, ethoxylated fatty methyl ester, ethoxylation, ethylene oxide, fatty methyl ester, foam, hydrolysis, magnesium oxide, nonionic surfactant, phase diagram, solid catalyst.

For the purpose of estimating the reaction mechanism of the direct ethoxylation of a fatty ester in the presence of an Al-Mg composite oxide catalyst, a labeled fatty methyl ester C 11 H 23 CO 18 OCH 3 containing 18 O isotope was synthesized and directly ethoxylated. The product was evaluated by gas chromatography-mass spectrometry (GC-MS). The GC-MS spectra showed that the 18 O isotope label was present only in the methoxy group at the molecular end of the ethoxylated fatty methyl ester. This supports the reaction mechanism of coordination anionic polymerization where the bond between the acyl and methoxy groups of the fatty methyl ester molecule was broken, caused by the bifunctional effect of the acid-base active sites; an intermediate chemisorption species was formed; and then ethylene oxide was addition-polymerized sequentially, in parallel. JAOCS 74, 19-24 (1997). KEY WORDS:Al-Mg composite oxide catalyst, coordination anionic polymerization, direct ethoxylation, ethoxylated fatty methyl ester, ethoxylation, ethylene oxide, fatty methyl ester, nonionic surfactant, reaction mechanism, solid catalyst.In the previous paper (1), we reported that the direct ethoxylation of a fatty methyl ester without active hydrogens in the molecule did not proceed in the presence of an ordinary homogeneous catalyst, such as NaOH (2), but readily proceeded over the novel metal ion-containing MgO, especially an Al ion-containing MgO catalyst. The resultant ethoxylated fatty methyl ester was a monoester-type nonionic surfactant which was substantially completely homogeneous.Also, the possibility was proposed that the reaction proceeded by a coordination anionic polymerization mechanism on the surface of the solid catalyst, and that ethylene oxide was directly inserted between the acyl and methoxy groups of the fatty methyl ester.In this paper, the tracer experiment with the 18 O stable isotope was carried out to reveal the insertion position of the ethylene oxide on the solid catalyst and to establish the ethoxylation reaction mechanism (3-5). EXPERIMENTAL PROCEDURESSynthesis of labeled methyl ester. The method used for synthesizing the fatty acid methyl ester labeled with an 18 O stable isotope (relative isotopic abundance 0.20%) is shown in Scheme 1 (6-7). To 80 mL of a solution of 0.6 g of 18 O-labeled methanol (EURISCO-TOP, Saint-Aubin Cedex, France: 18 O concentration 98.7 atom %, purity 99.1%) and 8.94 g of ordinary methanol (refined by distillation of methanol for high-performance liquid chromatography (HPLC), manufactured by Kanto Chemical, Tokyo, Japan) in pyridine (special grade pyridine, manufactured by Junsei Chemical (Tokyo, Japan) with added CaH 2 , and distilled to be refined), 178 g (0.357 mol, 1.2 equivalents) of n-dodecanoyl chloride (special grade n-dodecanoyl chloride, manufactured by Tokyo Chemical Industry, Tokyo, Japan, and distilled to be refined) was added dropwise gradually for 1 h while the solution was vigorously stirred. Immediately after the addition of acid chloride was completed, 100 mL water was ad...

During direct ethoxylation of fatty methyl ester over Al-Mg composite oxide catalyst, the activity was nearly proportional to the total number of active Al acidic sites on the catalyst surface per unit weight of catalyst. Lower active Al acidic site densities resulted in a narrower ethylene oxide (EO) adduct distribution of obtained ethoxylate. We developed a new catalyst with a large surface area on which many acidic sites are distributed uniformly by partially poisoning the Al acid sites of high-Al content Al-Mg composite oxide with alkali. This catalyst was used for direct ethoxylation of fatty methyl esters to obtain ethoxylated fatty methyl esters with narrow EO adduct distribution efficiently. JAOCS 74, 817-822 (1997). KEY WORDS:Adduct distribution, Al-Mg composite oxide catalyst, direct ethoxylation, ethoxylated fatty methyl ester, ethoxylation, ethylene oxide, fatty methyl ester, solid catalyst.

Ethoxylated fatty methyl esters (EFME) are nonionic surfactants obtained by direct insertion of ethylene oxide to fatty methyl esters in the presence of a composite metal oxide catalyst. Results of cumulative skin irritation testing of EFME on guinea pigs indicate that EFME are less irritating compared to ordinary alcohol ethoxylates (AE). Good skin compatibility of EFME is further illustrated by an in vitro hemolysis test and an in vitro cytotoxicity test. From the standpoint of environmental properties, EFME are readily biodegradable and are less toxic than AE . These results indicate the outstanding dermatological compatibility and good environmental compatibility of EFME. JSD 1, 93-97 (1998).KEY WORDS: Acute toxicity to fish, Al-Mg composite oxide catalyst, biodegradation, ecotoxicity, ethoxylate, ethoxylated fatty methyl ester, fatty methyl ester, skin compatibility.Many studies on characteristics of alkylene oxide-based nonionic surfactants, represented by alcohol ethoxylates (AE) and nonyl phenol ethoxylate, have been done since the 1950s. Today, vigorous studies on the effects of surfactants on organisms and the environment are being done owing to increased global environmental protection.Ethoxylated fatty methyl esters (EFME) are nonionic surfactants obtained by direct insertion of ethylene oxide (EO) to fatty methyl esters in the presence of a composite metal oxide catalyst (1-4). Fatty methyl ester precursors are important derivatives from natural oils and fats. EFME have been compared to common AE with respect to surface-chemical and physico-chemical properties. Compared to AE, EFME exhibit better foam-breaking, and the gelling region of EFME aqueous solutions is smaller (5-7). EFME and AE have similar surface tension-lowering characteristics (5-7).In this paper, in vivo and in vitro results for evaluating skin compatibility of EFME are reported. Biodegradability and ecotoxicity are discussed as well. EXPERIMENTAL PROCEDURESMaterials. EFME, listed in Table 1, were synthesized by the method of Hama et al. (4) from fatty methyl esters having various alkyl chain lengths 10,12,14,16; Lion Corp., Tokyo, Japan) and EO (Mitsubishi Chemical, Tokyo, Japan) in the presence of the surface-modified Al-Mg composite oxide catalyst. The following materials were used as controls for each test-lauryl alcohol ethoxylates: C 12 AE (Emalex series; Nihon Emulsion Corp., Tokyo, Japan); alkyl polyglycosides (APG): C 8-12 APG and C 12 APG (Henkel KGaA, Düsseldorf, Germany); sodium N-lauroyl-N-methyl-β-alaninate: LMA (Mitsui Toatsu Chemicals, Inc., Tokyo, Japan); and sodium N-lauroyl-L-glutamate: LG (Ajinomoto Co., Inc., Tokyo, Japan).Cumulative skin irritation test. Five solutions [20% (vol/vol) aqueous] of EFME test material were applied on the intact, shaved dorsal skin (2 × 2 cm) of three albino guinea pigs, Hartley strain, females. A dose of 0.3 mL was administered daily for 3 d by painting without occlusion. On each day of treatment and after application, erythema (score 0-4) and edema (score 0-4) were assessed acco...

In the presence of a surface-modified Al-Mg composite oxide catalyst, ethoxylated fatty methyl esters with different hydrophobic group structures and different chainlengths of polyoxyethylene were synthesized from fatty methyl esters by direct ethoxylation. Each ethoxylated fatty methyl ester obtained showed a narrow ethylene oxide (EO) adduct distribution. Foaming, ability to lower surface tension, ability to lower interfacial tension, wettability, and dye solubilization were measured. Ethoxylated methyl laurate with about 60 to 70% EO content was found to be the most suitable as a base surfactant for household detergents. JAOCS 74, 823-827 (1997).KEY WORDS: Direct ethoxylation, ethoxylated fatty methyl ester, ethylene oxide, fatty methyl ester, foaming, interfacial tension, nonionic surfactant, solubilization, surface tension, wettability.The synthesis of an ethoxylated fatty methyl ester (EFME) by the direct ethoxylation of a fatty methyl ester has been reported recently (1-7). In a previous paper, we reported that this reaction proceeded easily in the presence of an Al-Mg composite catalyst with or without surface modification (1,2). The EFME products made in this manner are almost 100% homogeneous in monoester and show good surface-active properties, such as ability to lower surface tension, wettability, and solubilization. They are anticipated to be new esterether type nonionic surfactants that can be favorably utilized in the detergent industry (1,4,5,8).In this report, we will discuss how and to what degree the structure of hydrophobic groups and polyoxyethylene (POE) chainlength of the EFME influence surfactant properties. EXPERIMENTAL PROCEDURES Materials.In the presence of a surface-modified Al-Mg composite oxide catalyst, EFME with a narrow ethylene oxide (EO) adduct distribution were synthesized from fatty acid methyl esters (FAME) of various alkyl chainlengths (Paster series; Lion Corp., Tokyo, Japan) and EO (Mitsubishi Chemical, Tokyo, Japan) by the method of Hama et al. (9). The combinations of FAME alkyl chainlength and average POE chainlength used for the property evaluations are shown in Table 1.Analysis for EO adduct distribution. The EO adduct distributions of EFME were measured by liquid chromatography under the following conditions: column, Zorbax C 8 (4.6 mm × 250 mm; DuPont, Boston, MA); mobil phase, CH 3 CN/H 2 O = 60:40; ultraviolet detector (SPD-10A; Shimadzu, Kyoto, Japan); measuring wavelength, 220 nm.Examples of EO adduct distributions of the ethoxylated methyl laurate (C 12 -EFME) with different EO chainlengths are shown in Figure 1A. Examples of EFME with 9 moles of EO and different alkyl chainlengths are shown in Figure 1B.Cloud point. Aqueous cloud points were measured visually at surfactant concentrations of 1%.Foaming and foam stability. Foaming and foam stability of 1% aqueous solutions of each sample were measured by the Ross-Miles Method at 25°C (10). Foam stability was calculated based on the change of the foam heights from soon after dropping the sample solution (t = 0) t...