Monoalkanolamide

Monoa.lka.nola.mine Condensates. Coco, lauric, oleic, and stearic monoethanolamides and monoisopropanolamides are the principal surfactants ia the monoalkano1 amide group (Table 24). Monoalkanolamides are generally water-iasoluble soHds that are easily solubilized by hydrophilic surfactants. Except for solubiUty and viscosity, properties and uses are similar to the diethanolamides. Manufacturing processes and yields have been described (96). 

There has been much activity in this field of corrosion inhibition in recent years which appears to have been prompted by health and safety requirements. As with engine coolants, the use of nitrites, particularly where amines may also be present, needs to be considered carefully. Nitrites have been widely used in cutting, grinding, penetrating, drawing and hydraulic oils. Suggested replacements for nitrites and/or amines make use, inter alia, of various borate compounds, e.g. monoalkanolamide borates. Molybdates have also been proposed in conjunction with other inhibitors, e.g. carbox-ylates, phosphates, etc . Water-based metalworking fluids usually contain other additives in addition to corrosion inhibitors, e.g. for hard-water stability, anti-foam, bactericidal proderties and so on. Thus, claims are made for oil-in-water emulsions with bactericidal and anti-corrosion properties. 

Alkanolamides are produced by condensation of fatty esters or acids with an alkanolamine. The monoalkanolamides account for 30% of market while diethanolamides account for the bulk of the rest with the balance being made up of a few specialised materials. 

Viscosity building with AOS is more difficult than with alkyl sulfates, although it can be done with the same types of materials, such as monoalkanolamides and salt [11-13], In addition, the detergent has been reported to leave a harsher feel than lauryl and laureth sulfates [13],... 

Diethanolamides are generally more soluble than monoalkanolamides, while super amides are less water soluble than regular (Kritchevsky) amides. Super amides are generally preferred in household products because they have a lower odour (due to their lower free amine content). Monoethanolamides are more effective than diethanolamides in building viscosity, while super amides are better at building viscosity than regular amides. 

Alkanolamides are the reaction products of mono- or dialkanolamines with fatty acids or their esters to form the respective secondary or tertiary amides, examples of which are depicted in Scheme 1.8. " Monoalkanolamides can be prepared by the reaction of monoalkanolamines with triglycerides such as coconut or palm kernel oil as well as from fatty acids or their methyl esters. The reaction of MEA with triglyceride at temperatures of 140-160°C liberates glycerin as a by-product, and because of the stability of the secondary amide formed, the reaction can be driven to a very low ester content with only a slightly super-stoichiometric amount of MEA. 

Alkali. The amide group in monoalkanolamides is resistant to alkalis, but is hydrolysed by boiling for 6h in IM potassium hydroxide in ethylene glycol. The sulphate group is not affected by this treatment. 

Sulphosuccinate surfactants are of two main types, namely monoesters of C12-C18 alcohols and diesters of C6-Cg alcohols. Monoesters of ethoxy-lated alcohols and monoalkanolamides also exist. Both types may be synthesised by addition of sodium sulphite or ammonium bisulphite across the double bond of a mono- or diester of maleic acid. In the latter case the product may contain small quantities of mono- or dialkyl aspartate. 

With monoalkanolamide or ethoxylated monoalkanolamide sulphate. Acid hydrolysis (section 2.4.4). Then any of the following. 

Chem. Descrip. Coconut monoalkanolamide Ionic Nature Nonionic... 

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