GB665264A - Improvements in or relating to improved detergent products and processes of preparing the same - Google Patents

Abstract

A process for the conversion of multiacylated alkylolamines formed by the reaction of alkylolamines with an acylating substance having 8-14 carbon atoms in the molecule, at a temperature sufficiently high to cause substantial reaction between the reactants, into monoacylated alkyl-olamines comprises incorporating into the reaction products of the alkylolamines and the acylating substance approximately 10-50 per cent of an alkylolamine soap of a higher fatty acid having more than 14 carbon atoms per molecule, based on the weight of the final mixture, and allowing the mixture to age at a lower temperature than the original reaction temperature. The acylating substances may be carboxylic acids, and the chlorides, esters or anhydrides of carboxylic acids. The alkanolamines may be primary and secondary alkylolamines such as monoethanolamine, monopropanolamine, diethanolamine, diglycerolamine, diisopropanolamine and dipropanolamine. The alkylolamine soap of the higher fatty acid may be added as such or may be formed by the addition of the higher fatty acid to the reaction mixture so that the soap is formed by the interaction of fatty acid and the free alkylolamine present in the mixture. Higher fatty acids which may be used include saturated or unsaturated fatty acids having about 16 to 18 carbon atoms in the molecule such as oleic, stearic, palmitic, or linoleic acid or mixtures of fatty acids obtained from soybean oil, corn oil or linseed oil. In an example, 1 mole. of coconut oil and 9 moles. of diethanolamine are heated together at 155 DEG C., with stirring, under an inert atmosphere of nitrogen until the titratable basicity of the mixture becomes constant. The reaction mixture is then cooled to about 70 DEG C. and 25 parts by weight of oleic acid added for every 100 parts of reaction mixture. The resulting mixture is then aged at about 60 DEG C. for about 36 hours. In another example 1 mole. of coconut oil fatty acids is heated with 3 moles of diethanolamine under a reduced pressure of about 40 mm. of mercury until the soap content is reduced to about 10 per cent, the reaction mixture cooled to about 90 DEG C. and about 20 per cent by weight of a mixture of stearic and palmitic acids added. The whole is allowed to age at 60 DEG C. for about 48 hours. The final products are said to be suitable detergents for washing fabrics (see Group III). U.S.A. Specification 2,483,253 is referred to.ALSO:Detergent compositions comprise a mixture of (1) the condensation products of alkylolamines and an acylating substance having 8-14 carbon atoms in the molecule, the products containing a substantial proportion of monoacylated alkylolamines, and (2) approximately 10-50 per cent of an alkylolamine soap of a higher fatty acid having more than 14 carbon atoms per molecule, based on the weight of the final detergent product. The acylating substance may be a carboxylic acid, a carboxylic acid chloride, a carboxylic acid ester or a carboxylic acid anhydride. Example of suitable alkylolamines are primary and secondary alkylolamines such as monoethanolamine, monopropanolamine, diethanolamine, diglycerolamine, diisopropanolamine, and dipropanolamine. Examples of suitable higher fatty acids are saturated or unsaturated single or mixed fatty acids preferably having about 16 to 18 carbon atoms in the molecule, such as oleic, stearic, palmitic or linoleic acid or the fatty acids of soya bean oil, corn oil and linseed oil. The acylated alkylolamines may be prepared by the two-stage process described in U.S.A. Specification 2,483,253 in which the multiacylated alkylolamines formed in the first stage of the process are converted into monoacylated alkylolamines in a second stage by an aging process in the presence of an alkylolamine soap of a fatty acid having 8-14 carbon atoms in the molecule, which soap functions as an aging catalyst. When the acylating substance having 8-14 carbon atoms in the molecule is a fatty acid, by controlling the reaction temperature and time, a complete conversion of the alkylolamine soap first formed into multiacylated alkylolamines may be prevented and sufficient soap left in the first stage reaction mixture to catalyze the conversion of the multiacylated into monoacylated alkylolamines in the second stage of the process. When employing an acylating substance incapable of forming soap with the alkylolamine, such as a triglyceride oil or fat, the reaction is carried out until the fat has substantially reacted with the alkylolamine, and then before the aging step a sufficient amount of 8-14 carbon atom fatty acid is added to form with any excess of alkylolamine the desired amount of soap. The compositions may also be prepared by reacting an excess of a primary or secondary alkylolamine with the acylating agent until condensation has proceeded to the desired stage, adding the higher fatty acid to the reaction mixture so as to form an alkylolamine soap, and allowing the resultant mixture to age (see Group IV(b)). In an example, 1 mole of coconut oil is reacted with 4.5 moles of dipropanolamine at 150 DEG C. at about 40 mm. of mercury pressure until the mixture has a constant titratable basicity. To the resulting mixture is added an additional 4.5 moles of dipropanolamine and then 7 per cent of coconut oil fatty acids. The whole is aged for about 48 hours at 60 DEG C. after which there is added 30 parts of oleic acid for every 100 parts of reaction product. Comparative data are given for washing tests carried out with tallow soap, with the acylated alkylolamine component containing excess alkylolamine and with the latter to which varying proportions of oleic acid have been added and the mixture aged.