DE4300935A1 - Prepn. of new sulphonated di-ester of 1,4-butene diol and fatty acid - Google Patents

Abstract

New sulphonated diesters (I) of 1,4-butene diol with fatty acids are prepd. by reacting cpds. of formula (II):R1-CO-O-(C2H4O)n-CH2-CH=CH-CH2-(OC2H4)m-O-OC-R2with a sulphonating agent, followed by neutralisation with a base. R1CO,R2CO = 6-22C acyl gp. with 0-3 C=C bonds; m,n = 0-10.

Description

Field of the Invention

The invention relates to novel sulfonated diesters of 1,4- Butenediol with fatty acids, a process for their preparation by reacting the diesters with sulfating agents and subsequent neutralization, as well as the use of this Products for the production of surfactants.

State of the art

The technically most important anionic surfactants are those containing a sulfo group, the The water solubility of these surfactants is largely determined. At These surfactants become sulfate surfactants and sulfonate surfactants distinguished. Sulphate surfactants are half esters of Sulfuric acid.

The sulfonate surfactants are salts of alkyl sulfonic acids. For These can further improve water solubility Sulfonate surfactants contain glycol ether groups. The  Sulfonate group can be introduced by or fatty alcohol derivatives with sulfating agents and then neutralized with aqueous bases. Sulfonate surfactants are described, for example, in DE-A-38 30 569, DE-A-39 36 001, DE-A-37 25 030, DE-A-38 28 892 and DE-A-38 40 092.

Sulfonated esters of unsaturated fatty acids or fatty alcohols, as they proved for example in DE-A-38 09 822, DE-A-39 26 344 or DE-A- 37 20 000 are described.

A special interest lies in being mild, special to provide skin-compatible surfactants that are easily biodegradable. Such surfactants are for Example sulfonated esters of dicarboxylic acids with unsaturated fatty alcohols or alkoxylates, as in the DE-A-39 32 492 are described. As particularly mild and for particularly suitable for use in cosmetic products The sulfosuccinates have proven to be surfactants. Under Sulfosuccinates are the addition products of Sodium hydrogen sulfite on maleic acid ester. For the production the ester is preferably maleic or fumaric acid however from maleic anhydride, which in the presence of p- Toluenesulfonic acid with fatty alcohols or fatty alcohol ethoxylates are implemented. However, these connections have the disadvantage that the double bonds for their preparation the maleic or fumaric acid does not sulfate easily can be. Sodium hydrogen sulfite is used as the sulfating agent used, which is reacted with the ester in an autoclave becomes. However, this method has the disadvantage that the Sodium hydrogen sulfite is a solid and expensive in the Handling is. In addition, maleic or fumaric acid  as well as maleic anhydride comparatively expensive Input materials. The object of the present invention is to use mild surfactants To make available in their properties the Correspond to sulfosuccinates, but simpler and are cheaper to manufacture.

Surprisingly, it was found that one Compounds analogous to sulfosuccinate by reacting Diesters of unsaturated diols or alkoxylates of unsaturated diols with saturated, unsaturated or receives alkoxylated fatty acids.

Description of the invention

The present invention relates to sulfonated Diesters obtained by connecting to the general formula I.

R ¹ -CO-O- (C ₂ H ₄ O) _n -CH ₂ -CH = CH-CH ₂ - (OC ₂ H ₄ ) _m -O-OC-R ² I

in the
R ¹ CO and R ² CO represent a linear or branched acyl radical having 6 to 22 carbon atoms and each having 0, 1, 2 or 3 double bonds,
n and m for O or numbers from 1 to 10
stand, where R ¹ CO and R ² CO can be the same or different,
reacted with sulfating agents and then neutralized with bases.

The compounds according to the invention are sulfonates of ethoxylated and non-ethoxylated diesters of 1,4-butenediol and fatty acids. Compounds of the formula I are used in which the acyl radicals R ¹ CO and R ² CO are derived from fatty acids having 6 to 22 carbon atoms. The radicals R ¹ CO and R ² CO can be the same or different. The preparation of the starting compounds with the general formula I is easier if the groups R ¹ CO and R ² CO are the same. Fatty acid residues in which R ¹ CO and R ² CO are each saturated hydrocarbon residues having 6 to 14 carbon atoms are preferred. Caproic acid, caprylic acid, capric acid, lauric acid and myristic acid and their technical mixtures, such as are obtained, for example, by pressure splitting of coconut or palm kernel oil, have proven to be suitable fatty acids. Such compounds have the advantage that they are particularly water-soluble.

Unsaturated fatty acids are preferably 16 to 22 Carbon atoms, such as palmoleic acid, Oleic acid, elaidic acid, petroselinic acid, linoleic acid, Linolenic acid, elaeostearic acid, gadoleic acid, erucic acid and their technical mixtures, such as those found in the pressure splitting of natural fats and oils after sulfonation compounds are obtained which in Fatty acid residue contain other sulfonate groups, resulting in a Increases water solubility. A preferred one unsaturated fatty acid is oleic acid.

If the solubility behavior should be varied further, can as starting compounds with the formula I also ethoxylated Connections are used, i. H. Connections with the Formula I in which n and m are a number from 1 to 10. Ethoxylated compounds in which n and m represent numbers of 1 to 7 are due to technical reasons prefers.  

Another object of the present invention is a Process for the preparation of sulfonated diesters, in which a diester with the general formula I

R ¹ -CO-O- (C ₂ H ₄ O) _n -CH ₂ -CH = CH-CH ₂ - (OC ₂ H ₄ ) _m -O-OC-R ² I

in the
R ¹ CO and R ² CO represent a linear or branched acrylic radical having 6 to 22 carbon atoms and each having 0, 1, 2 or 3 double bonds,
n and m for 0 or numbers from 1 to 10
stand, where R ¹ CO and R ² CO can be the same or different,
reacted with sulfating agent and then neutralized with base.

The sulfonation of the starting compounds can in itself known manner, either continuously or batchwise respectively. Reactors that work on the falling film principle, are preferred for procedural reasons. When Sulfating agents come and chlorosulfonic acid in particular gaseous sulfur trioxide. The gaseous Sulfur trioxide is usually mixed with an inert gas, preferably air or oxygen, diluted and in the form of a Gas mixture, which the sulfonating agent in a Concentration from 1 to 8, preferably 2 to 5% by volume contains, used.

The molar ratio of starting compound to Sulfating agent can be 1: 0.95 to 1: 2 and preferably 1: 1.0 to 1: 1.3. Usually the sulfonation is at 40 up to 100 ° C. With regard to the viscosity of the Output connections on the one hand and the color quality of the resulting sulfonation products, on the other hand, has a temperature range of 40 to 70 ° C proved to be optimal.  

The acidic crude sulfonation product obtained in the sulfonation is then neutralized with a base and adjusted to a pH of 6.5 to 8.5. As bases for the neutralization come alkali metal hydroxides such as sodium, potassium and lithium hydroxide, alkaline earth metal oxides and hydroxides such as magnesium oxide, magnesium hydroxide, calcium oxide and calcium hydroxide, ammonia, mono-, di- and tri-C _2-4 alkanolamines, for example mono-, Di- and triethanolamine as well as primary, secondary or tertiary C _1-4 alkylamines into consideration. The neutralization bases are preferably in the form 5 to 55 wt. -% aqueous solutions used, 5 to 25 wt. % aqueous sodium hydroxide solutions are preferred. In the course of the neutralization, an intermediate hydrolysis of cyclic or bridged sulfonation products formed to give open-chain sulfonic acids takes place.

The sulfonation products can be neutralized after in a known manner by adding hydrogen peroxide or sodium hypochlorite solution. In doing so, based on the solids content of the sulfonation products in the solution, 0.2 to 2 wt .-% hydrogen peroxide, calculated as a 100% substance or corresponding amounts Sodium hypochlorite used. The pH of the solutions can using suitable buffering agents, e.g. B. with Sodium phosphate or citric acid should be kept constant. To stabilize against bacterial infestation is recommended preservation, e.g. B with formaldehyde solution, p- Hydroxybenzoate, sorbic acid or other known Preservatives.  

Industrial applicability

The sulfonated diesters according to the invention have surfactant properties. You promote for example the wetting of solid surfaces and the Emulsification of otherwise immiscible Phases. The sulfonated diesters according to the invention are particularly mild due to its succinate-analogous structure Suitable for surfactants.

Another object of the invention therefore relates to Use of the compounds according to the invention for the preparation detergents, dishwashing detergents, cleaning agents, and Means for hair and body care, in which they are in quantities from 1 to 50, preferably 5 to 30 wt .-%, based on the Means that may be included.

Preparation of the starting compounds

The ester compounds of the formula I are prepared by reacting 1,4-butenediol with acids of the formula R ¹ -COOH and / or R ² -COOH in a manner known per se in the presence of esterification catalysts at 50 to 70 ° C. with the separation of water.

To produce ethoxylated esters, the ester product is also used Ethylene oxide (EO) in the presence of a catalyst, for example sodium methylate or more hydrophobic Hydrotalcite, reacted at 120-180 ° C and 1 to 5 bar, where the EO units between the ester group -COO- and the Insert the alkyl residue of the 1,4-butenediol. It is also possible 1,4-butenediol and / or the fatty acid in itself first  known alkoxylation and the resulting To bring polyglycol ether to the reaction.

Examples I. General instructions for the preparation of the 1,4-butenediol ester

In a reaction vessel with a stirring device and Water separators are 2 moles of fatty acid and 1 mole of 1,4- Butenediol (commercial product) and 0.25 wt .-% - based on the Feedstocks - presented as a catalyst and while introducing nitrogen and stirring so long to approx. 170 ° C heated until no more water is separated (approx. 4-6 Hours). The catalyst is then filtered off. The Diesters come in handy as light yellow colored solids quantitative yield obtained.

Manufacturing example

In a reaction vessel with a stirring device and Water separators were 877 g (6 mol) of caprylic acid (Commercial product), 264 g (3 mol) 1,4-butenediol (Commercial product) and 2.9 g of tin cut and weighed in Nitrogen introduction and stirring at approx. 170 ° C for 6 hours heated. About the amount of water separated the Controlled reaction progress. The catalyst was filtered off. 1020 g of butenedicaprylic acid ester were obtained as slightly colored solid.  

II. Preparation of the sulfonated diesters Examples 1 to 2

General instructions for the sulfonation of diesters: In a 1-1 sulfation reactor with jacket cooling and Gas inlet tube became 1 mol ester A or B at T = 50 ° C reacted with 1.05 mol of sulfur trioxide. The sulfur trioxide was obtained from a corresponding amount of 65% by heating. % oleum driven off with nitrogen on a Concentration of 5 vol.% Diluted and within 50 min. initiated in the starting product. The raw sulfation product was then neutralized with aqueous sodium hydroxide solution and Hydrolyzed for 1 h on the steam bath under pH control. The Characteristic data of the products are summarized in Table 1.

The anionic surfactant content (WAS) and the unsulfonated proportions (US) were based on the DGF standard methods, Stuttgart, 1950-1984, H-III-10 and G-II-6b determined. The sulfate content was as Calculated sodium sulfate, the determination of water content was carried out according to the Fischer method.

Table 1: Preparation of the sulfonated esters

Claims (8)

1. Sulfonated diesters, obtainable by making compounds with the general formula I R ¹ -CO-O- (C ₂ H ₄ O) _n -CH ₂ -CH = CH-CH ₂ - (OC ₂ H ₄ ) _m -O -OC-R ² Iin der
R ¹ CO and R ² CO represent a linear or branched acyl radical having 6 to 22 carbon atoms and each having 0, 1, 2 or 3 double bonds,
n and m for 0 or numbers from 1 to 10
stand, where R ¹ CO and R ² CO can be the same or different,
reacted with sulfating agents and then neutralized with bases. 2. Sulfonated diesters according to claim 1, characterized in that R ¹ CO and R ² CO are saturated acyl radicals which have 6 to 14 carbon atoms. 3. Sulfonated diesters according to claim 1, characterized characterized in that n and m for numbers from 2 to 7 stand. 4. A process for the preparation of sulfonated diesters, in which compounds having the formula I R ¹ -CO-O- (C ₂ H ₄ O) _n -CH ₂ -CH = CH-CH ₂ - (OC ₂ H ₄ ) _m -O -OC-R ² Iin der
R ¹ CO and R ² CO represent a linear or branched acyl radical having 6 to 22 carbon atoms and each having 0, 1, 2 or 3 double bonds,
n and m represent 0 or numbers from 1 to 10,
where R ¹ CO and R ² CO may be the same or different, reacted with sulfating agents and then neutralized with bases. 5. The method according to claim 4, characterized in that one as the sulfonating agent chlorosulfonic acid or gaseous Uses sulfur trioxide. 6. The method according to claim 4, characterized in that the compounds with the general formula I or II and the sulfating agent in a molar ratio of 1: 0.95 to 1: 2. 7. The method according to claim 4, characterized in that the neutralization with 5 to 55 wt. -% aqueous bases from the group formed by alkali metal hydroxides, alkaline earth metal oxides and hydroxides, ammonia, mono-, di- and tri-C _2-4 -alkanolamines and primary, secondary and tertiary C _1-4 -alkylamines. 8. Use of the sulfonated diesters according to claim 1 for Manufacture of washing, rinsing, cleaning and Conditioners and hair and body care products.