FATTY ALKANOLAMIDES •2oo I i . i De/• AMme-----• t i . IOO0 ß ß . , . , . . ß 800 D•A AMIDE ß ß ' [ I . 600 - • -- I ' ' MIXTURE OF MEA AND I. DEA DEA AMIDE 4.* AMIDE ß • DEA AMIDE •00 'l • ..... : ME A A•' O•'------•--• ß [ It l ' - V- -•_ DEA-AMß•.,.._ ' DEA AMIDE MONO ESTER•I Ii - , •oo,- •. D'ESTERAM'r•E•I ß '•. oL • ' ': -' ' , .• v EL L 0 I0 20 30 40 50 60 70 80 FRACTION Figure 2. Superamide made from methyl esters, 1:1 ratio 111 substantiated by examining the spectra in relation to the CH band at 2915 and 2840 cm -t to the "amide I" band at 1620 cm -t o[ the various fractions. The ratio o[ the CH band to the "amide I" and the melting points o[ the [ractions are presented in Table II. The variability in the melting points of the fractions is indicative of a eutectic mixture. The superamides are usually made from a mixture ot• methyl myris- rate and methyl laurate which are C•4 and C•2 fatty acid esters, respec- tively, the ratio being Ct2/C•4 or 0.86. If the ratio of CH to amide of the average of fractions 50 and 51 is taken in relation to the average of fractions 55 and 57, we obtain 0.83, indicating that the amide is made from a mixture of methyl myristate and methyl laurate. Samples of the t•ractions were dissolved in alcohol and a few drops of bromcresol green indicator were added. Fractions 29 through 32 were yellow, indicating acidic groups gg through 36 (green) indicated neutral molecules 37 was a blue-green showing the presence of the NH or amine group of the monoethanolamide. Fractions 38 through 73 were green, 74 was blue-green, and from 75 to the end were blue. The blue color is due to the presence of the amido-amine. Sample No. g, a 2:1 adduct, was examined similarly to Nos. 1 and 2.

112 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS Table II Ratio of CH/Amide Indicating Relative Chain Length Melting Point, CH Amide Ratio of Fractions øC Absorption, % Absorption, % CH/Amide 41 36 56 66 0.85 42 36 43 40 44 40 45 40 47 40 49 40 50 46 52 57 0.91 51 47 45 50 0.90 52 47 53 42 54 43 55 46 56 74 0.76 56 46 57 42 60 78 0.77 58 41 59 46 60 46 61 43 62 45 44 55 0.80 63 46 64 46 65 44 Figure 3 shows the histogram of particular interest were Fractions 22 and 24 which were identified as monoethanolamide ester and mono- ethanolamide. With this as background, Sample No. 4 was analyzed in greater detail. Sample No. 4, a 2:1 adduct, is presented in Fig. 4. This was a fresh sample which was liquid when it was received. Fractions 1 through 17 were combined and examined by infrared the material was found to be di(2-ethylhexyl)phthalate. It is not included in Table I because it is not one of the components. The phthalate ester came from the plastic cap and liner and was also found in other samples which were packaged in plastic containers. Fraction 18 is lauric acid, 23 is the ester of mono- ethanolamide, 25 is a diethanolamide. Fraction 32 is also a diethanol- amide however, this fraction also contains a small amount of an ester amide. Fractions 33 and 39 are diethanolamide Fraction 36 shows the diethanolamide with a trace of ester. Fraction 47 is also a diethanol- amide however, the spectrum does not have the detail of a pure amide,