Amid ethoxylates

Approximate, 1990. Table 4 Hsts many of the commercially available substituted fatty acid amides. The /V,/V-dimetby1 amides, ethoxylated amides, and other specialty substituted amides are available ia commercial quantities, but are of lower volume. Table 4. Substituted Fatty Acid Amides ... 

Synonyms Coconut acid amide ethoxylates Formula RC0NH(CH2CH20)nH, R = coco, n = 3-8 Uses Emulsifier for liq. detergents, textile auxs., cosmetics, pesticides Trade Name Synonyms Empilan LP10 [Huntsman Surf. Sciences http //www. huntsman. com/surface sciences]... 

Figure 6.11 illustrates the difference in surface composition with respect to the surfactant for a polymerizable amide ethoxylate and a conventional nonionic surfactant of similar hydrophilic-lipophilic balance (HLB). Surfactant concentrations at the film-air interface were... 

The difference in behaviour between the nonylphenol ethoxylate and the amide ethoxylate is probably due to the fact that the latter surfactant becomes immobilized through coupling to binder molecules during the drying process. Once covalently incorporated into the network, the migration process will cease. Another contributing... 

Figure 6.11. Relative surface concentration of surfactant as a function of drying time, as determined by ESCA. The NP ethoxylate is nonylphenol ethoxylate (12 EO) and the amide ethoxylate is linseed oil fatty acid monoethanolamide ethoxylate (14 EO). (From K. Holmberg, Prog. Colloid Polym. Sci., 101, 69 (1996))...

A wetting agent may be used to improve the hydrophilicity of the fibers. Suitable wetting agents should be compatible with the aliphatic polyesters. Examples of wetting agents are surfactants, ethoxylated alcohols, or acid amide ethoxylates (25). 

Over 50% of the consumption of traditional blooming antistatic agents consists of ethoxylated amines and glyceryl monostearate (GMS), and much of the rest consists of alkyl sulfonates, fatty alkanolamides and amide ethoxylates. Films containing amide antistats usually pass the American Mil-B-81705C (commonly known as Mil spec) test for electrostatic dissipation when the film is a few days old, but not after three or four weeks. This has been attributed to the formation of crystallites of the antistatic agent. 

Fatty Amine Ethoxylates Fatty Amide Ethoxylates Glycerolmonosteatate Sodium Alkane Sulphonate Concentrates... 

The most common nonionic surfactants are those based on ethylene oxide, referred to as ethoxylated surfactants [11-13]. Several classes can be distinguished alcohol ethoxylates, alkyl phenol ethoxylates, fatty acid ethoxylates, monoalkaol-amide ethoxylates, sorbitan ester ethoxylates, fatty amine ethoxylates and ethylene oxide-propylene oxide copolymers (sometimes referred to as polymeric surfactants). 

Environmental awareness and protection have led to the development of more environmentally benign surfactants. There is a trend of substituting petrochemicals by renewable raw materials. For this reason there is currently much interest in fatty acid-based surfactants. For both fatty alcohol ethoxylates and fatty amide ethoxylates the raw material for the hydrophobic group are triglyceride oils. The triglycerides are present in plants such as rapeseed, coconuts, soya, canola, sunflour, and tallow. Fatty acids, as used for the production of fatty amide ethoxylates, are obtained from saponification of the triglycerides. Fatty alcohols, which are used to produce fatty alchol ethoxylates, need a saponification step to obtain the fatty acid, followed by a reduction, usually via the methyl ester, to obtain the alcohol. 

Fatty amide ethoxylates differ from the fatty alcohol ethoxylates in terms of aquatic toxicity and biodegradation. The toxicity of the fatty amide ethoxylates has been found lower than for alkylphenol and alcohol ethoxy-... 

FIG. 3 CMC values for several fatty amide ethoxylates as a function of oxyethylene units, as determined by fluorescence. (Adapted from Ref. 8.)... 

TABLE 1 Micellar Data Obtained from H-NMR Self-diffusion from Fatty Amide Ethoxylates Containing 10 Oxythelene Units... 

The adsorbed amount and the apparent head group area obtained from the ellipsometry meaurements are shown in Table 2 together with the cross-sectional head group area as determined from the surface tension measurements for a series of fatty amide ethoxylates in comparison with fatty alcohol ethoxylates [18,19]. For the surfactants as measured by Folmer et al. [19], it can be seen that the adsorption areas as obtained from ellipsometry are up to 3.5 times larger than the areas observed from the surface tension measurements. As mentioned by the authors, there are two important differences... 

The effect of the amide group can be seen when the adsorption results of stearyl amide ethoxylate are compared with those of stearyl ethoxylate. It is found that the adsorption areas at a solid-liquid interface and at the air-liquid interface are somewhat larger for the stearyl amide ethoxylate. It is concluded that the attractive force between the amide groups plays a smaller role than the decrease in CPP, resulting in less favorable packing at the interface. These results are in agreement with the effect of the amide group as seen in pure dodecyl surfactants [18]. 

The effect of unsaturations in the hydrocarbon chain of the fatty amide ethoxylates is found to be significant at the liquid air interface as compared with the solid-liquid interface [8,19]. This effect is ascribed to a decrease in rotational freedom of the chain, causing increased bulkiness and rigidity in the hydrocarbon chain [21,22,27]. When looking at the solid-liquid interface the head group area seems only to be slightly affected. This is explained by the phenomenon that at the liquid-air interface selective adsorption occurs, leading to a CPP closer to 1, and therefore the effects of the hydrocarbon chains become more pronounced. At the solid-liquid interface the effect of the oxyethylene chain is the dominant factor. 

The phase behavior of fatty amide ethoxylates is compared with that of alcohol ethoxylates [19]. At low surfactant concentrations micellar isotropic phases are formed for both surfactant types. At higher concentrations, hexagonal phases are formed when 10 oxyethylene units are present. For surfactants with longer head groups a cubic region appears between the micellar and the hexagonal region. When double bonds are present in the hydrophobe an isotropic melt is formed while the saturated amide and alcohol ethoxylates form crystals for 100% surfactant. 

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