Ethylene oxide content

The physical properties of the fatty acid ethoxylates depend on the nature of the fatty acid and even more on ethylene oxide content. As the latter increases, consistencies of the products change from free-flowing Hquids to slurries to firm waxes (qv). At the same time, odor, which is characteristic of the fatty acid, decreases in intensity. Odor and color stabiUty are important commercial properties, particularly in textile appHcations. Oleic acid esters, though possessing good functional properties, cannot be used because they tend to yellow on exposure to heat and air. 

Ethoxylation of alkyl amine ethoxylates is an economical route to obtain the variety of properties required by numerous and sometimes smaH-volume industrial uses of cationic surfactants. Commercial amine ethoxylates shown in Tables 27 and 28 are derived from linear alkyl amines, ahphatic /-alkyl amines, and rosin (dehydroabietyl) amines. Despite the variety of chemical stmctures, the amine ethoxylates tend to have similar properties. In general, they are yellow or amber Hquids or yellowish low melting soHds. Specific gravity at room temperature ranges from 0.9 to 1.15, and they are soluble in acidic media. Higher ethoxylation promotes solubiUty in neutral and alkaline media. The lower ethoxylates form insoluble salts with fatty acids and other anionic surfactants. Salts of higher ethoxylates are soluble, however. Oil solubiUty decreases with increasing ethylene oxide content but many ethoxylates with a fairly even hydrophilic—hydrophobic balance show appreciable oil solubiUty and are used as solutes in the oil phase. 

Nuclear Magnetic Resonance (nmr). The nmr analysis has been used in the polymer industry for some time to measure properties such as amount and type of branching, polymerized ethylene oxide content, and hydroxyl content. The same techniques are applicable to waxes, and are used for both characterization and quality control. 

Although poloxamers show poor biodegradability, they exhibit very low acute toxicity [92] and are reported as having low potential for causing irritation and skin sensitization [26]. Toxicity decreases as ethylene oxide content increases, and the least toxic poloxamers are approved as food additives [80]. 

American Society of Testing and Materials, Standard Test Method for Ethylene Oxide Content of Polyethoxylated Nonionic Surfactants, D2959-76 (1984). 

There was always the question about the effect of the different polyether polyol on the PEER polyester. Originally, it was suspected that high-ethylene-oxide-content polyethers may produce less fumarate in the polyester and thus will cure... 

A. Nordon, C. Meunier, R.H. Carr, P.J. Gemperline, and D. Littlejohn, Determination of the ethylene oxide content of polyether polyols by low-field H nuclear magnetic resonance spectrometry. Anal. Chim. Acta, 472, 133-140... 

The optimum alcohol and amount of ethylene oxide is dependent upon the type of soil and the type of foam desired for for the finished product. Figure 1(4) shows the optimum ethylene oxide content in a heavy-duty powder formulation similar to that shown in the foregoing. Lines are "isodets"—lines of equal detergency ranging from a lower detergency rating of 1 to a high of 4. 

Structure-activity relationships between several nonionic surfactants and three water-soluble herbicides have been studied (58). In general it has been shown that the herbicide, the surfactant concentration, the hydrophilic constitution (ethylene oxide content), and the hydrophobic portion of the molecule all markedly influence toxicity. 

Generally a peak of maximum enhancement is reached as the ethylene oxide content is raised and the molecule becomes more hydrophilic, but after a certain content (depending on concentration) the enhancement drops away again. This is illustrated for two herbicides and two surfactant concentrations in Figure 2. 

Terepolymers having M s less than 3200 daltons have been prepared consisting of THE, 3-ethyl-tetrahydrofuran, and ethylene oxide, which were catalyzed by the acid resin NAEION NR-50. Terpolymer hydrophobic/hydrophilic properties were controlled by the ethylene oxide content. 

A reactor was charged with THE (2.22 mol), 3-ethyl-tetrahydrofuran (0.4 mol), 1,4-butanediol(0.01 mol), andNAEION NR-50 (10 g)cryoground to less than 80 mesh. The mixture was heated to 50°C and treated with ethylene oxide (0.19 mols) over a 4 hour period. Heating was continued for an additional 15 minutes and then cooled to 30°C and fdtered. The polymer solution was concentrated, and the product was isolated in 24% yield as a viscous liquid having a of 3,100 daltons with a THE content of 72 mol%, ethylene oxide content of 25 mol%, and a 3-ethyl-tetrahydrofuran content of 3 mol%. 

Entry THF (g) Ethylene Oxide (g) Co-component (g) Polymer Mn (daltons) THF Content (%) Co-component (%) Ethylene Oxide Content (%)... 

At higher EO levels, the foam volume produced by AEGS and AESo surfactants were less adversely affected by the presence of an oil phase than were other surfactants studied (Table I. Figure 1). This behavior was likely due to the formation of an oil/water emulsion which stabilized the fluid films between gas bubbles. Although foam volumes were smaller, at 75°C in three different brines, the sensitivity of AE and AES surfactants to the presence of decane decreased with increasing surfactant ethylene oxide content. 

EO/mole of parent alcohol and then gradually declined. Somewhat different behavior was observed using supercritical COj-extracted stock tank oil which had a higher carbon number 26 vs 16), a higher asphaltene content (1.52% vs 0.78%), and a higher combined acid and base number (0.85% vs 0.33) than the unextracted oil (see above). The maximum foam volume was observed at a lower ethylene oxide content (for 15 20 moles of EO vs 30 moles of EO for unextracted oil). The decline in foam volume with further increases in EO content was much more rapid in the presence of COj-extracted oil. This behavior was also observed for 5 alcohol ethoxyl-ates and Cg alcohol ethoxylates. 

Correlation equations relating surfactant chemical structure to performance characteristics and physical properties have been established. One atmosphere foaming properties of alcohol ethoxyl-ates and alcohol ethoxylate derivatives have been related to surfactant hydrophobe carbon chain length, ethylene oxide content, aqueous phase salinity, and temperature. Similar correlations have been established for critical micelle concentration, surfactant cloud point, and surfactant adsorption. 

Magdassi S, Frank SG. Formation of oil in glycerolAvater emulsions effect of surfactant ethylene oxide content. / Disper Sci Technol 1990 11 519-528. 

Materials Determination of the Polymerized Ethylene Oxide Content of Polyester Polyols, 5 pp (Comm D-20)... 

Sample Identification. Given the number of samples and compositions, a general code was created as explained in Table II. In this table, the polyol type is identified by molecular weight and ethylene oxide content. Thus 40/15 refers to a polyol with M = 4000 and 15% (w/w) of ethylene oxide end capping agent. The last two labels in Table 2 indicate mold temperature and catalyst content. 

A similar detergency maximum at almost the same oxyethylene content has been observed in the removal of oily soil from metal surfaces using similar surfactants in an alkaline, built formulation (Komor, 1969). The maximum here is at 68% oxyethylene (about 11 oxyethylene units per nonylphenol) at bath temperatures from 40 to 80°C. For a series of polyoxyethylenated nonrandom linear alkylphenols with Cg-Cig alkyl chains, optimum removal of sebum soil from cotton at 49°C and 50 and 300 ppm water hardness was obtained at 63-68% oxyethylene content (Smithson, 1966). A study of the removal of oily soil from cotton and permanent press cloths, and of clay from permanent press cloths by commercial POE alcohols, showed that POE Ci2-Ci4 alcohols with 60% or greater ethylene oxide content achieved the best soil removal (Cox, 1989). 

ASTM D4875, Standard Test Methods for Polyurethanes Raw Materials Determination of the Polymerised Ethylene Oxide Content of Polyether Polyols, 1999. 

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