WO1995007256A1

WO1995007256A1 - N-alkoxy polyhydroxy fatty acid amides and synthesis thereof

Info

Publication number: WO1995007256A1
Application number: PCT/US1994/009556
Authority: WO
Inventors: Jeffrey John Scheibel; Daniel Stedman Connor; Yi-Chang Fu
Original assignee: The Procter & Gamble Company
Priority date: 1993-09-09
Filing date: 1994-08-24
Publication date: 1995-03-16
Also published as: AU7603494A

Abstract

N-alkoxy polyhydroxy fatty acid amides surfactants are prepared in a substantially solvent-free process by reacting a fatty acid ester with an N-alkoxy polyhydroxy amine in the presence of a base catalyst, especially sodium methoxide. Thus, the palm fatty acid amides of N-(3-methoxypropyl) glucamine and N-(2-methoxyethyl) glucamine are prepared. Methods for laundering fabrics and for cleaning hard surfaces, especially glass, are also disclosed. Surfactant mixtures comprising the N-alkoxy polyhydroxy fatty acid amides and N-alkyl polyhydroxy fatty acid amides are also disclosed.

Description

N-ALKOXY POLYHYDROXY FATTY ACED AMIDES AND SYNTHESIS THEREOF

FIELD OF THE INVENTION The present invention relates to certain N-alkoxy polyhydroxy fatty acid amide detersive surfactants and their method of synthesis.

BACKGROUND OF THE INVENTION The formulation of detergent compositions presents a considerable challenge, since effective compositions are required to remove a variety of soils and stains from diverse substrates. In particular, the removal of greasy/oily soils quickly and efficiently can be problematic. While a review of the literature would seem to indicate that a wide selection of surfactants is available to the detergent manufacturer, the reality is that many such materials are specialty chemicals which are not suitable in low unit cost items such as home-use detergent compositions. The fact remains that most home-use detergents still comprise one or more of the conventional ethoxylated nonionic and sulfated or sulfonated anionic surfactants, presumably due to economic considerations.

The challenge to the detergent manufacturer seeking improved fabric cleaning has been increased by various environmental factors. For example, some nonbiodegradable ingredients have fallen into disfavor. Effective phosphate builders have been banned by legislation in many countries. Moreover, many surfactants are often available only from nonrenewable resources such as petrochemicals.

Accordingly, the detergent manufacturer is quite limited in the selection of surfactants which are effective cleaners, biodegradable and, to the extent possible, available from renewable resources such as natural fats and oils, rather than petrochemicals.

Considerable attention has lately been directed to nonionic surfactants which can be prepared using mainly renewable resources, such as fatty esters and sugars.

One such class of surfactants includes the N-alkyl polyhydroxy fatty acid amides. Moreover, the combination of such nonionic surfactants with conventional anionic surfactants such as the alkyl sulfates, alkyl benzene sulfonates, alkyl ether sulfates, surfactants such as the alkyl sulfates, alkyl benzene sulfonates, alkyl ether sulfates, and the like has also been studied. Indeed, substantial success in the formulation of dishwashing compositions has recently been achieved using the N-alkyl polyhydroxy fatty acid amides. However, even these superior surfactants do suffer from some drawbacks. For example, their solubility is not as high as might be desired for optimal formulations and this is exacerbated at chain lengths of about C\ and above. At high concentrations in water they can be difficult to handle and pump, so additives must be employed in manufacturing plants to control their viscosity. While quite compatible with anionic surfactants, their compatibility can be diminished substantially in the presence of water hardness cations. And, of course, there is always the objective to find new surfactants which lower interfacial tensions to an even greater degree than the N-alkyl polyhydroxy fatty acid amides at low temperatures in order to increase cleaning performance.

It has now been determined that the N-alkoxy polyhydroxy fatty acid amide surfactants derived from the so-called "palm stearin" fatty acids, i.e., mainly Cjg-Cig chain lengths, surprisingly differ from ir counterpart N-alkyl polyhydroxy fatty acid amide surfactants in several imp .nt and unexpected ways which are of considerable benefit to detergent formulators. The palm stearin N-alkoxy polyhydroxy fatty acid amide compounds herein substantially reduce interfacial tensions, and thus provide for high cleaning performance detergent compositions, even at low wash temperature. The palm stearin surfactants herein exhibit much greater solubility in water than the corresponding Cjg N-methylglucamide surfactants, even at low temperatures (5°-40°C). The high solubility of the surfactants herein allows them to be formulated as modern concentrated detergent compositions, and their longer fatty chain lengths gives them a stronger detergency action than the soluble C12-C14 N-alkyl compounds. However, the slow kinetics at low temperature (< T Krafft - 33°C) makes the palm materials sometimes less desirable for lew temperature laundry applications. The surfactants herein can be easily prepared as low viscosity, pumpable solutions (or in the melt) at concentrations as high as 50-100%, which allows them to be easily handled in the manufacturing plant. Moreover, the high solubility of the surfactants herein makes them more compatible with calcium and magnesium cations, even in relatively concentrated compositions. Of considerable importance to the formulation of hand dishwashing and glass cleaning compositions, the N-alkoxy surfactants herein allow the formulation of cleaning compositions with reduced filming and spotting. The surfactants herein also have the advantage of providing a lower sudsing profile than the N-alkyl polyhydroxy fatty acid amides, which desirably decreases the carry-over of suds into the rinse bath.

In addition, the manufacture of N-alkyl polyhydroxy fatty acid amides having desirable low color and little or no contamination with cyclized by-products is best achieved in the presence of organic hydroxy solvents, as disclosed in U.S. Patent 5,194,639, Connor, Scheibel and Severson, issued March 16, 1993. While quite effective for its intended purpose, it will be recognized that the introduction of a solvent into any manufacturing process can lead to complexities in handling and some additional expense for solvent recycling, and the like. It has now been discovered that the N-alkoxy polyhydroxy fatty acid amides herein can be prepared substantially in the absence of added solvents. The lower melting points of the N-alkoxy compounds as compared with their N-alkyl counterpart surfactants facilitate this process.

Accordingly, the present invention provides new, highly soluble, highly detersive surfactants which have the additional advantage that they can be prepared in an efficient and effective manner without the need for reaction solvents.

BACKGROUND ART Japanese Kokai HEI 3[1991]-246265 Osamu Tachizawa, U.S. Patents 5,194,639, 5,174,927 and 5,188,769 and WO 9,206,171, 9,206,151, 9,206,150 and 9,205,764 relate to various polyhydroxy fatty acid amide surfactants and uses thereof.

SUMMARY OF THE INVENTION

The present invention encompasses a substantially solvent-free process for preparing low-color N-alkoxy polyhydroxy fatty acid amides, comprising reacting an N-alkoxy polyhydroxy amine reactant with a fatty acid ester reactant in the presence of a base catalyst, said reaction being conducted substantially in the absence of reactant solvents. Preferably, the base catalyst used in the process is an alkoxide material, especially sodium methoxide or the sodium salts of glycerin or propylene glycol. The fatty acid "ester" can be a C -C22 fa ty acid alkyl ester or, for the sake of economy, a Cg-C22 fatty acid mono-, di- or tri-glyceride ester. Thus, natural plant oils such as palm oil, soy oil, coconut oil, palm kernel oil, canola oil and the like, can be used in the process.

In a preferred mode of the reaction, the fatty acid ester is a Cg-C22 fatty acid methyl ester and the N-alkoxy polyhydroxy amine reactant is selected from N-(2- methoxy)ethyl glucamine and N-(3-methoxy)propyl glucamine. In order to minimize color formation and to minimize ester amide or cyclic by-products formed by the polyol substituent, the process herein is preferably conducted at a temperature below about 170°C, most preferably in the range from about 140°C to about 70°C. If desired, any unreacted N-alkoxyamino polyol remaining in the product can be acylated (50°C-85°C) with an acid anhydride, e.g., acetic anhydride, maleic anhydride, or the like, in water to minimize the overall level of such residual amines in the product. Residual sources of straight chain fatty acids, which can suppress suds, can be depleted by reaction with, for example, monoethanolamine (50°C-85°C). The invention also encompasses novel detergent compounds of the formula

where R contains 11, 13 or 15-17 carbon atoms and can be saturated, branched, substituted and/or unsaturated (e.g., oleyl and ricinolyl) and mixtures thereof, R^ is ethylene or propylene (including branched propylene), R-2 is methyl and Z is a polyhydroxy hydrocarbyl moiety having 3 or more hydroxyl units, e.g., units derived from reducing sugars such as glucose (preferred), maltose and the like. Such amide compounds with their formulas depicted in standard typescript format include: CnH23C(O)N(CH2CH2θCH3)CH2(CHOH)4CH₂OH C 1 ιH23C(O)N(CH₂CH2CH₂OCH3)CH2(CHOH)4CH2θH Ci3H27C(O)N(CH2CH2CH₂OCH3)CH2(CHOH)4CH₂OH

C 13H27C(O)N(CH₂CH2OCH3)CH2(CHOH)4CH₂OH C 15H3₁C(O)N(CH₂CH2OCH3)CH2(CHOH)4CH₂OH; Ci7H₃₅C(O)N(CH2CH2θCH3)CH2(CHOH)4CH2θH; C₁5H_{3 1}C(O)N(CH2CH2CH2OCH3)CH2(CHOH)4CH₂OH; Ci7H₃5C(O)N(CH2CH2CH2OCH3)CH2(CHOH)4CH₂OH; as well as the corresponding oleoyl glucamine compounds, i.e., Ci7H33C(O)N- (CH2CH2CH₂OCH3)CH2(CHOH)4CH₂OH and Ci7H33C(0)N(CH₂CH2θCH₃)- CH2(CHOH)4CH2OH and the ricinolyl (i.e., 12-hydroxyoleoyl) glucamine com¬ pounds, i.e., CH₃(CH2)5CHOHCH2CH=CH(CH2)7C(O)(CH2CH2CH2OCH₃)- CH₂(CHOH)₄CH₂OH and CH3(CH₂)5CHOHCH2CH=CH(CH2)7C(O)(CH₂CH2. OCH3)CH2(CHOH)4CH2OH, and mixtures of compounds which comprise the mixed palm oil (including palm kernel oil) chain-length fatty acid amides of an amine selected from the group consisting of HN(CH₂CH₂OCH3)CH2(CHOH)4CH2OH and HN(CH₂CH2CH2OCH3)CH2(CHOH)4CH₂OH. The invention also provides a method for laundering fabrics or cleaning hard surfaces, comprising contacting said fabrics or hard surfaces with an aqueous solution containing at least 10 ppm, preferably 100 pp - 10,000 ppm, of a Cio-C_jg N-alkoxy polyhydroxy fatty acid amide surfactant, preferably with agitation. In yet another aspect, the invention encompasses a surfactant mixture comprising a member selected from the group of N-alkoxy polyhydroxy fatty acid amides and a member selected from the group consisting of N-alkyl polyhydroxy fatty acid amides such as those described in U.S. Patent 5,194,639, Connor et al, March 16, 1993. Preferred mixtures of this type include those wherein the N-alkoxy polyhydroxy fatty acid amide is selected from the Cio-Cjg fatty acid amides of N-(3- methoxypropyl) glucamine and N-(2-methoxyethyl) glucamine and wherein the N- alkyl polyhydroxy fatty acid amides are CJO- IS fatty amides of the N-(Cι-C6 alkyl) glucamines, especially the N-methyl glucamines. Such mixtures prepared at weight ratios of N-alkoxy to N-alkyl surfactant of about 10: 1 to about 1: 10, especially about 1:1, are desirably more fluid at concentrations of 30% and greater in water than are the N-alkyl polyhydroxy fatty acid amides per se.

All percentages, ratios and proportions herein are by weight, unless otherwise specified. All documents cited are incorporated herein by reference. DETAILED DESCRIPTION OF THE INVENTION The N-alkoxy and N-aryloxy polyhydroxy fatty acid amide surfactants used in the practice of this invention are quite different from traditional ethoxylated nonionics, due to the use of a linear polyhydroxy chain as the hydrophilic group instead of the ethoxylation chain. Conventional ethoxylated nonionic surfactants have cloud points with the less hydrophilic ether linkages. They become less soluble, more surface active and better performing as temperature increases, due to thermally induced randomness of the ethoxylation chain. When the temperature gets lower, ethoxylated nonionics become more soluble by forming micelles at very low concentration and are less surface active, and lower performing, especially when washing time is short. In contrast, the polyhydroxy fatty acid amide surfactants have polyhydroxyl groups which are strongly hydrated and do not exhibit cloud point behavior. It has been discovered that they exhibit Krafft point behavior with increasing temperature and thus higher solubility at elevated temperatures. They also have critical micelle concentrations similar to anionic surfactants, and it has been surprisingly discovered that they clean like anionics. Moreover, the polyhydroxy fatty acid amides herein are different from the alkyl polyglycosides (APG) which comprise another class of polyhydroxyl nonionic surfactants. While not intending to be limited by theory, it is believed that the difference is in the linear polyhydroxyl chain of the polyhydroxy fatty acid amides vs. the cyclic APG chain which prevents close packing at interfaces for effective cleaning.

With respect to the N-alkoxy and N-aryloxy polyhydroxy fatty acid amides, such surfactants have now been found to have a much wider temperature usage profile than their N-alkyl counterparts, and they require no or little cosurfactants for solubility at temperatures as low as 5°C. Such surfactants also provide easier processing due to their lower melting points. It has now further been discovered that these surfactants are biodegradable.

As is well-known to formulators, most laundry detergents are formulated with mainly anionic surfactants, with nonionics sometimes being used for grease/oil removal. Since it is well known that nonionic surfactants are far better for enzymes, polymers, soil suspension and skin mildness, it would be preferred that laundry detergents use more nonionic surfactants. Unfortunately, traditional nonionics do not clean well enough in cooler water with short washing times.

It has now also been discovered that the N-alkoxy and N-aryloxy polyhydroxy fatty acid amide surfactants herein provide additional benefits over conventional nonionics, as follows: a. Much enhanced stability and effectiveness of new enzymes, like cellulase and lipase, and improved performance of soil release polymers; b. Much less dye bleeding from colored fabrics, with less dye transfer onto whites; c. Better water hardness tolerance; d. Better greasy soil suspension with less redeposition onto fabrics; e. The ability to incorporate higher levels of surfactants not only into Heavy Duty Liquid Detergents (HDL's), but also into Heavy Duty Granules (HDG's) with the new solid surfactants herein; and f. The ability to formulate stable, high performance "All-Nonionic" or "High Nonionic Low Anionic" HDL and HDG compositions.

For purposes of clarity, the following defines the terms used herein. By "substantially solvent-free" or "substantially in the absence of reactant solvents" herein is meant that no solvent need be added to the reaction system comprising the fatty acid ester, the N-alkoxy polyhydroxy amine and the base catalyst. It will be appreciated that minor quantities of alcohol will be introduced into the system if an alkoxide-type base catalyst is employed, i.e., some methanol will be introduced with sodium methoxide, some ethanol with sodium ethoxide, and the like. However, the amounts thus introduced will typically not be sufficient to provide a solvent function for the reactants in the overall reaction mixture. If solvents such as propylene glycol are used, the levels are typically 10% or less, preferably less than 5% of the reaction mixture.

By "low-color" herein is meant a N-alkoxy polyhydroxy fatty acid amide reaction product which is substantially white or light beige. On the standard Gardner scale, a color in the range of 0-4, preferably 0-2, most preferably 0, is secured.

By "cyclized by-products" herein is meant contaminants which undesirably form during the synthesis by internal cyclization of the polyol structure (e.g., glycityl) of the N-alkoxy polyhydroxy fatty acid amides herein, presumably by a dehydration reaction. The term "cyclized by-products" does not refer to natural cyclic structures, such as those which may be present in di- and higher saccharide reducing sugars such as maltose. The process of this invention provides N-alkoxy polyhydroxy fatty acid amides which are substantially free, i.e., which contain less than 10%, preferably 1% or less, of undesirable "cyclized by-products".

By "ester amides" herein is meant N-alkoxy polyhydroxy fatty acid amides whose polyol units have undesirably undergone a further reaction with the fatty acid ester reactant to form one or more fatty ester linkages. The process of this invention provides N-alkoxy polyhydroxy fatty acid amides which are substantially free, i.e., which contain less than 10%, preferably less than 5%, most preferably 1% or less, of such ester-amides. By "interfacial tension" ("IFT") herein is meant the tension measured at the oil/water interface. EFT measurements using the spinning drop technique, are disclosed by Cayias, Schechter and Wade, "The Measurement of Low Interfacial Tension yja the Spinning Drop Technique", ACS Symposium Series No. 8 (1975) ADSORPTION AT INTERFACES, beginning at page 234. Equipment for running EFT measurements is currently available from W. H. Wade, Depts. of Chemistry and Chemical Engineering, The University of Texas at Austin, Austin, Texas 78712.

By "low interfacial tension" herein is meant an IFT which is sufficiently low that "spontaneous emulsification", i.e., rapid emulsification with little or no mechanical agitation, can occur. IFT's of about 0.15 dynes/cm, and below, even as low as 0.06 dynes/cm, can easily be secured by the present compositions at usage levels of 50-20,000 ppm. The "spontaneous emulsification" of greasy/oily soils provided by the compositions herein can be simply, but convincingly, demonstrated by admixing a detergent composition in accordance with the invention with water. After dissolution of the detergent, a few drops of oil to which a colored oil-soluble dye has been added are added to the detergent solution. With minimal agitation, the entire system appears to take on the color of the dye, due to the dyed oil having been finely dispersed by the spontaneous emulsification effect. This dispersion remains for a considerable length of time, typically 30 minutes to several hours, even when agitation has stopped. By contrast, with surfactant systems which fail to provide spontaneous emulsification, the dyed oil droplets produced during agitation r?idly coalesce to form one or more relatively large oil globules at the air/water interface.

More specifically, this demonstration of spontaneous emulsification can be conducted as follows.

A consumer relevant test soil is dyed with 0.5% Oil Red EGN. A 100 ml sample of the detergent composition being tested is prepared at the desired concentration (typically, about 500 ppm) and temperature in water which is "pre- hardened" to any desired concentration of calcium ions (typically, about 48 ppm), and contained in an 8 oz. capped jar. The sample pH is adjusted to the intended end- use pH (typically in the range of 6.5 to 10) and 0.2 g of the test soil is added. The jar is shaken 4 times and the sample graded. Alternatively, the sample is placed in a beaker and stirred with a stir bar for 15 seconds. The sample is graded as follows:

0 = Clear solution with large red oil droplets in it (0.1-5 mm diameter), i.e., no emulsification;

1 = Solution has a definite pink appearance with red oil droplets in it (0.1- 1 mm), i.e., slight emulsification;

2 = Solution is dark pink with small red droplets in it, i.e., moderate emulsification;

3 = Solution is red with small red droplets in it (l-200mm), i.e., emulsification is substantial; 4 - Solution is dark red with little or no visible droplets (<l-50mm), i.e., emulsification is complete. Note: The grading can also be done spectrophotometrically (based on light transmittance).

Detergent compositions which contain N-alkoxy polyhydroxy fatty acid amide surfactants of the present type can typically achieve grades at the 3-4 level under conventional liquid dishwashing concentrations and temperatures. The process herein is conducted under the following conditions. The reactants noted hereinafter are by way of illustration and are not intended to limit the scope of the invention. It is to be understood that the polyhydroxy amines used herein can be derived from an alkoxy amine and any desired reducing sugar, such as glucose (preferred), xylose, maltose, fructose, and the like. If desired, the water solubility of the solid N-alkoxy polyhydroxy fatty acid amide surfactants herein can be enhanced by quick cooling from a melt. While not intending to be limited by theory, it appears that such quick cooling re-solidifies the melt into a metastable solid which dissolves more readily in water than the pure crystalline form of the N-alkoxy polyhydroxy fatty acid amide. Such quick cooling can be accomplished by any convenient means, such as by use of chilled (0°C-10°C) rollers, by casting the melt onto a chilled surface such as a chilled steel plate, by means of refrigerant coils immersed in the melt, or the like. Such quick cooling typically solidifies the material almost instantaneously or within a few minutes. Preferred amine reactants used herein are prepared as follows.

Preparation of N-(2-methoxyethyDglucamine - N-(2-methoxyethyl)glu- cosylamine (sugar adduct) is prepared starting with 1728.26 g of 50 wt.% 2- methoxyethylamine in water (11.5 moles, 1.1 mole equivalent of 2-methoxy- ethylamine) placed under an N blanket at 10°C. 2768.57 grams of 50 wt.% glucose in water (10.46 moles, 1 mole equivalent of glucose), which is degassed with N , is added slowly, with mixing, to the methoxyethylamine solution keeping the temperature below 10°C. The solution is mixed for about 40 minutes after glucose addition is complete. It can be used immediately or stored 0°C-5°C for several days.

About 278 g (-15 wt.% based on amount of glucose used) of Raney Ni (Activated Metals & Chemicals, Inc. product sold under the trademark A-5000) is loaded into a 2 gallon reactor (316 stainless steel baffled autoclave with DISPERSIMAX hollow shaft multi-blade impeller) with 4L of water. The reactor is heated, with stirring, to 130°C at about 1500 psig hydrogen for 30 minutes. The reactor is then cooled to room temperature and the water removed to about 10% of the reactor volume under hydrogen pressure using an internal dip tube.

The reactor is vented and the sugar adduct is loaded into the reactor at ambient hydrogen pressure. The reactor is then purged twice with hydrogen. Stirring is begun, the reactor is heated to 50°C, pressurized to about 1200 psig hydrogen and these conditions are held for about 2 hours. The temperature is then raised to 60°C for 10 minutes, 70°C for 5 minutes, 80°C for 5 minutes, 90°C for 10 minutes, and finally 100°C for 25 minutes. The reactor is then cooled to 50°C and the reaction solution is removed to about 10% from the reactor under hydrogen pressure via an internal dip tube and through a filter in closed communication with the reactor. Filtering product under hydrogen pressure allows removal of any nickel particles without nickel dissolution. Solid N-(2-methoxyethyl)glucamine is recovered by evaporation of water and excess 2-methoxyethylamine. The product purity is approximately 90% by G.C. Sorbitol is the major impurity at about 10%. The N-(2-methoxyethyl)glucamine can be used as is or purified to greater than 99% by recrystallization from methanol.

Preparation of N-(3-methoxypropyDglucamine - About 300 g (about 15 wt.% based on amount of glucose used) of Raney Ni (Activated Metals & Chemicals, Inc. product A-5000 or A-5200) is contained in a 2 gallon reactor (316 stainless steel baffled autoclave with DISPERSIMAX hollow shaft multi-blade impeller) pressurized to about 300 psig with hydrogen at room temperature. The nickel bed is covered with water taking up about 10% of the reactor volume. 1764.8 g (19.8 moles, 1.78 mole equivalent) of 3-methoxypropylamine (99%) is maintained in a separate reservoir which is in closed communication with the reactor. The reservoir is pressurized to about 100 psig with nitrogen. 4000 g of 50 wt.% glucose in water (11.1 moles, 1 mole equivalent of glucose) is maintained in a second separate reservoir which is also in closed communication with the reactor and is also pressurized to about 100 psig with nitrogen.

The 3-methoxypropylamine is lc. ded into the reactor from the reservoir using a high pressure pump. Once all the 3-methoxypropylamine is loaded into the reactor, stirring is begun and the reactor heated to 60°C and pressurized to about 800 psig hydrogen. The reactor is stirred at 60°C and about 800 psig hydrogen for about 1 hour.

The glucose solution is then loaded into the reactor from the reservoir using a high pressure pump similar to the amine pump above. However, the pumping rate on the glucose pump can be varied and on this particular run, it is set to load the glucose in about 1 hour. Once all the glucose has been loaded into the reactor, the pressure is boosted to about 1500 psig hydrogen and the temperature maintained at 60°C for about 1 hour. The temperature is then raised to 70°C for 10 minutes, 80°C for 5 minutes, 90°C for 5 minutes, and finally 100°C for 15 minutes.

The reactor is then cooled to 60°C and the reaction solution is removed from the reactor under hydrogen pressure via an internal dip tube and through a filter in closed communication with the reactor. Filtering under hydrogen pressure allows removal of any nickel particles without nickel dissolution. Solid N-(3-methoxypropyl)glucamine is recovered by evaporation of water and excess 3-methoxypropylamine. The product purity is approximately 90% by

G.C. Sorbitol is the major impurity at about 3%. The N-(3-methoxypropyl)- glucamine can be used as is or purified to greater than 99% by recrystallization from methanol.

EXAMPLE I

Mixed Palm Fatty Acid Methoxypropyl Glucamide - N-(3-methoxypro- py glucamine, 1265 g (5.0 mole) is melted at 145°C under nitrogen. A vacuum is applied to 38.1 cm (15 inches) Hg for 10 minutes to remove gases and moisture. Separately, hardened palm stearine methyl ester, 1375 g (5.0 mole) is preheated to

130°C and added to the melted amine with rapid stirring. Immediately following,

25% sodium methoxide, 54 g (0.25 mole) is added through a dropping funnel. Half the catalyst is added before the reaction is homogeneous to control the hard reflux of methanol. After homogeneity is reached, the other half of the catalyst is added within 10 minutes.

Reactants weight: 2694 g

Theoretical MeOH generated: (5.0 x 32) + (0.75 x 54) + (0.25 x 32) = 208.5 g MeOH

Theory product: FW 496 2480 g 5.0 mole The reaction mixture is homogeneous within 5 minutes of adding the first half of the catalyst at 132°C. It is allowed to reflux in order to cool to 90-95°C in a 5 liter, 4 neck round bottom flask equipped with a heating mantle, TRUBORE stirrer with TEFLON paddle, gas inlet and outlet, THERMOWATCH, condenser, and air drive motor. When the first half of the catalyst is added, time = 0. At 40 minutes, a vacuum of 25.4 cm (10 inches) Hg is applied to remove methanol. At 48 minutes, vacuum is increased to 43.2 cm (17 inches) Hg. At 65 minutes, the remaining weight of methanol in the reaction is 2.9% based on the following calculation:

2559 g current reaction wt - (2694 g reactants wt - 208.5 g theoretical MeOH)/2559 g = 2.9% MeOH remaining in the reaction. By 120 minutes, the vacuum has been increased to 50.8 cm (20 inches) Hg.

At 180 minutes, the vacuum has been increased to 58.4 cm (23 inches) Hg and the reaction is poured into a stainless pan and allowed to solidify at room temperature. Also, the remaining weight of methanol is calculated to be 1.3%. After sitting for 4 days, it is hand ground for use. In an economical process, fatty glyceride esters can also be used in the foregoing process. Natural plant oils such as palm, palm kernel oil, soy and canola, as well as tallow are typical sources for such materials. Thus, for example, in an alternate mode, the above process is conducted using palm kernel oil to provide the desired mixture of N-alkoxyglucamide surfactants.

In the general manner of Example I, N-oleoyl-N-(3-methoxypropyl)glucamine is prepared by reacting 49.98 grams of N-(3-methoxypropyl)glucamine with 61.43 g of methyl o'eate in the presence of 4.26 g of 25 wt% NaOCH3. N-oleoyl-N-(2- methoxyethyl) glucamine is prepared in similar fashion.

EXAMPLE II

C}6 Methoxypropyl Glucamide - The reaction of Example I is repeated using an equivalent amount of methyl palmitate to replace the methyl stearate. The resulting N-hexadecanoyl-N-(3-methoxypropyl)glucamine has a melting point of

84°C. If desired, the product can be further purified using an acetone/methanol solvent.

EXAMPLE III C}2 Methoxypropyl Glucamide - The reaction of Example I is repeated using an equivalent amount of methyl laurate to replace the methyl stearate. The resulting N-dodecanoyl-N-(3-methoxypropyl)glucamine has a melting point of 64.1°C. This Cj2 compound is superior to its CJQ homologue with respect to detergency performance and is easier to formulate, especially in liquid products, than its Cj4 homologue.

In like manner, C12 N-(2-methoxyethyl)glucamide is prepared.

EXAMPLE IV

Cjg Methoxypropyl Glucamide - N-(3-methoxypropyl)glucamine, 40 g

(0.158 mole) is melted at 145°C under nitrogen. A vacuum is applied to 38.1 cm (15 inches) Hg for 5 minutes to remove gases and moisture. Separately, methyl stearate,

47.19 g (0.158 mole) is preheated to 130°C and added to the melted amine with rapid stirring along with 9.0 grams of propylene glycol (10 weight % based on reactants). Immediately following, 25% sodium methoxide, 1.7 g (0.0079 mole) is added. The reaction mixture is homogeneous within 2 minutes of adding the catalyst at 130°C. It is allowed to reflux in order to cool to 85-90°C in a 250 ml, 3 neck round bottom flask equipped with a hot oil bath, TRUBORE stirrer with TEFLON paddle, gas inlet and outlet, THERMOWATCH, condenser, and stirrer motor. The reaction requires about 35 minutes to reach 90°C. After 3 hours at 85-90°C a vacuum is applied to remove methanol. The reaction mixture is poured out into a jar after a total of 4 hours. The solid reaction product is recrystallized from 400 mis of acetone and 20 mis of methanol. The filter cake is washed twice with 100 ml portions of acetone and is dried in a vacuum oven. A second recrystallization is performed on 51.91 grams of the product of the first recrystallization using 500 mis acetone and 50 mis methanol to give after filtration, washing with two 100 ml portions of acetone and drying in a vacuum oven a yield of 47.7 grams of the N- octadecanoyl-N-(3-methoxypropyl)glucamine. Melting point of the sample is 89°C. If desired, the product can be further purified using an acetone/methanol solvent.

Glvceride Process If desired, the N-alkoxy and N-aryloxy surfactants used herein may be made directly from natural fats and oils rather than fatty acid methyl esters. This so-called "glyceride process" results in a product which is substantially free of conventional fatty acids such as lauric, myristic and the like, which are capable of precipitating as calcium soaps under wash conditions, thus resulting in unwanted residues on fabrics or filming/spotting in, for example, hard surface cleaners and dishware cleaners. Triglvceride Reactant - The reactant used in the glyceride process can be any of the well-known fats and oils, such as those conventionally used as foodstuffs or as fatty acid sources. Non-limiting examples include: CRISCO oil; palm oil; palm kernel oil; corn oil; cottonseed oil; soybean oil; tallow; lard; canola oil; rapeseed oil; peanut oil; tung oil; olive oil; menhaden oil; coconut oil; castor oil; sunflower seed oil; and the corresponding "hardened", i.e., hydrogenated oils. If desired, low molecular weight or volatile materials can be removed from the oils by steam- stripping, vacuum stripping, treatment with carbon or "bleaching earths" (diatomaceous earth), or cold tempering to further minimize the presence of malodorous by-products in the surfactants prepared by the glyceride process. N-substituted Polyhydroxy Amine Reactant - The N-alkyl, N-alkoxy or N- aryloxy polyhydroxy amines used in the process are commercially available, or can be prepared by reacting the co esponding N-substituted amine with a reducing sugar, typically in the presence of hydrogen and a nickel catalyst as disclosed in the art. Non-limiting examples of such materials include: N-(3-methoxypropyl) glucamine; N-(2-methoxyethyl) glucamine; and the like.

Catalyst - The preferred catalysts for use in the glyceride process are the alkali metal salts of polyhydroxy alcohols having at least two hydroxyl groups. The sodium (preferred), potassium or lithium salts may be used. The alkali metal salts of monohydric alcohols (e.g., sodium methoxide, sodium ethoxide, etc.) could be used, but are not preferred because of the formation of malodorous short-chain methyl esters, and the like. Rather, it has been found to be advantageous to use the alkali metal salts of polyhydroxy alcohols to avoid such problems. Typical, non-limiting examples of such catalysts include sodium glycolate, sodium glycerate and propylene glycolates such as sodium propyleneglycolate (both 1,3- and 1,2-glycolates can be used; the 1,2-isomer is preferred), and 2-methyl-l,3-propyleneglycolate. Sodium salts of NEODOL-type ethoxylated alcohols can also be used.

Reaction Medium - The glyceride process is preferably not conducted in the presence of a monohydric alcohol solvent such as methanol, because malodorous acid esters may form. However, it is preferred to conduct the reaction in the presence of a material such as an alkoxylated alcohol or alkoxylated alkyl phenol of the surfactant type which acts as a phase transfer agent to provide a substantially homogeneous reaction mixture of the polyhydroxy amine and oil (triglyceride) reactants. Typical examples of such materials include: NEODOL 10-8, NEODOL 23-3, NEODOL 25-12 AND NEODOL 11-9. Pre-formed quantities of the N-alkoxy and N-aryloxy polyhydroxy fatty acid amides, themselves, can also be used for this purpose. In a typical mode, the reaction medium will comprise from about 10% to about 25% by weight of the total reactants.

Reaction Conditions - The glyceride process is preferably conducted in the melt. N-substituted polyhydroxy amine, the phase transfer agent (preferred NEODOL) and any desired glyceride oil are co-melted at 120°C-140°C under vacuum for about 30 minutes. The catalyst (preferably, sodium propylene glycolate) at about 5 mole % relative to the polyhydroxy amine is added to the reaction mixture. The reaction quickly becomes homogeneous. The reaction mixture is immediately cooled to about 85°C. At this point, the reaction is nearly complete. The reaction mixture is held under vacuum for an additional hour and is substantially complete at this point.

In an alternate mode, the NEODOL, oil, catalyst and polyhydroxy amine are mixed at room temperature. The mixture is heated to 85°C-90°C, under vacuum. The reaction becomes clear (homogeneous) in about 75 minutes. The reaction mixture is maintained at about 90°C, under vacuum, for an additional two hours. At this point the reaction is complete.

In the glyceride process, the mole ratio of triglyceride oil: polyhydroxy amine is typically in the range of about 1 :2 to 1 :3.1.

Product Work-Up: The product of the glyceride process will contain the polyhydroxy fatty acid amide surfactant and glycerol. The glycerol may be removed by distillation, if desired. If desired, the water solubility of the solid polyhydroxy fatty acid amide surfactants can be enhanced by quick cooling from a melt, as noted above.

It is to be understood that the N-alkoxy polyhydroxy fatty acid amides herein can be used in a wide variety of detergent compositions, of which the following are by way of illustration and not limitation.

EXAMPLE V A clear, colorless dishwashing composition with high grease removal properties is as follows. Product pH is adjusted to 7.8.

Ingredient % (wt Ci2-14 N-(3-methoxypropyl) glucamide* 9.0

Ci2 ethoxy (l) sulfate 12.0

2-methyl undecanoic acid 4.5

C 12 ethoxy (2) carboxylate 4.5

C 12 alcohol ethoxylate (4) 3.0 C12 amine oxide 3.0

Sodium cumene sulfonate 2.0

Ethanol 4.0

Mg^4-1" (as MgCl₂) 0.2

Ca+÷ (as CaCl₂) 0.4 Water Balance

*Prepared as disclosed herein; Gardner color less than 1.

EXAMPLE VI A liquid laundry detergent composition herein comprises the following. Ingredient % (wt Ci2-i4EO 2.25 sulfate 15.0

C 12-14 alkyl sulfate 6.0

C 12- 14*N-(3 -methoxypropyl) glucamide 6.0

Sodium citrate 6.0

Monoethanolamine 2.5 Water/propylene glycol/ethanol ( 100 : 1 : 1 ) Balance

EXAMPLE VII A granular laundry detergent herein comprises the following. Ingredient % ⁽wt

C 12 alkyl benzene sulfonate 12.0 C 16- i8-N-(3-methoxypropyl) glucamide 12.0

Zeolite A (1-10 micrometer) 26.0 C 12-14 secondary (2,3) alkyl sulfate, Na salt 5.0 Sodium citrate 5.0

Sodium carbonate 20.0

Optical brightener 0.1 Detersive enzyme* 1.0

Sodium sulfate 9.0

Water and minors Balance

*Lipolytic enzyme preparation (LIPOLASE).

In the above formulation the glucamide surfactant can be replaced by an equivalent amount of the corresponding C i g_ j 8 amide of N-(2- methoxyethyl)glucamine.

EXAMPLE VIII A laundry bar suitable for hand-washing soiled fabrics is prepared by standard extrusion processes and comprises the following: Ingredient % (wt

C12-I6 alkyl sulfate, Na 20

Palm N-(3-methoxypropyl)glucamide* 5

Cl 1-13 alkyl benzene sulfonate, Na 10

Sodium tripolyphosphate 7

Sodium pyrophosphate 7

Sodium carbonate 25

Zeolite A (0.1-lOm) 5

Coconut monoethanolamide 2

Carboxymethylcellulose 0.2

Polyacrylate (m.w. 1400) 0.2

Brightener, perfume 0.2

Protease enzyme 0.3

Cellulase enzyme** 0.2

CaSO4 1

MgSO 1

Water 4

Filler*** Balance

•Prepared from mixed palm fraction fatty acids.

**As CAREZYME (Novo).

***Can be selected from convenient materials such as CaCO.,, talc, clay, silicates, and the like. EXAMPLE IX A surfactant mixture suitable for use in a laundry or dishwashing detergent is as follows.

Ingredient % (wt.) Ci6_ι N-(3-methoxypropyl) glucamide 50

C 12- 14 N-methylglucamide 50

While the foregoing illustrates the synthesis and detergent use of the surfactants herein, such surfactants can be used for a variety of other purposes: e.g., as emulsifiers and spreading agents for medicaments and agricultural chemicals such as pesticides, fungicides and herbicides; as emulsifiers for paints; as emulsifiers for liquid fabric softeners; in the formulation of cosmetics and shampoos; in antibacterial hand scrubs; for oil recovery; for auto waxes; for cleaning and sheeting water from surfaces, e.g., in auto washing products and for any other purpose where safe, effective emulsifiers are required. The surfactants herein are also useful as solid coatings for various detersive ingredients such as enzymes, bleach activators, percarbonate bleach, and the like. Preferred oil and grease emulsification and detergency are secured with the Ciβ-Ci surfactants herein.

It has also been determined that the C_jό-Ci amide surfactants herein, especially the N-(3-methoxypropyl) surfactants, exhibit unusual wetting/draining properties on smooth surfaces such as glass and ceramics. This allows for the formulation of hard surface cleaners, glass cleaners, "tub and tile" cleaners, and the like, with improved performance with respect to spotting and filming. The following examples further illustrate this aspect of the invention.

EXAMPLE X A bathroom tub and/or kitchen tile or window glass cleaner in spray form is as follows.

Ingredient % (wt

Octyl sulfate, Na 3.0

Lauryl sulfate, Na 2.0 Ci6_i8 N-(3-methoxypropyl) glucamide 1.5

EDTA 0.5

Water and minors Balance EXAMPLE XI

A liquid cleanser which removes mildew from tile grouting is as follows

Ingredient % (wt.)

Octyl sulfate, Na 1.0

Lauryl sulfate, Na 2.0

C-14-16 N-(2-methoxyethyl) glucamide 2.0

Sodium hypochlorite 1.5

Soluble silicate 0.5

NaOH/water to pH 13.5

Claims

What is claimed is:

1. Compounds of the formula

wherein R contains 11, 13 or 15-17 carbon atoms and mixtures thereof, R is ethylene or 2 propylene, R is methyl and Z is a polyhydroxy hydrocarbyl moiety having 3 or more hydroxyl units.

2. A glucose-derived compound according to Claim 1 which is Ci iH23C(O)N(CH2CH2CH2OCH3)CH₂(CHOH)4CH₂OH.

3. A glucose-derived compound according to Claim 1 which is Ci ιH23C(O)N(CH₂CH2θCH3)CH₂(CHOH)4CH2θH

4. A glucose-derived compound according to Claim 1 which is Ci 5H3 iC(O)N(CH2CH2OCH3)CH₂(CHOH)4CH₂OH.

5. A glucose-derived compound according to Claim 1 which is C 17H3₅C(O)N(CH2CH₂OCH₃ )CH₂(CHOH)₄CH₂OH.

6. A glucose-derived compound according to Claim 1 which is Ci5H3₁C(O)N(CH2CH2CH₂OCH3)CH₂(CHOH)4CH2OH.

7. A glucose-derived compound according to Claim 1 which is Ci7H35C(O)N(CH₂CH2CH2OCH3)CH2(CHOH)4CH₂OH.

8. A glucose-derived compound according to Claim 1 which is Ci3H27C(O)N(CH₂CH2CH2OCH3)CH2(CHOH)4CH₂OH.

9. A glucose-derived compound according to Claim 1 which is Ci3H27C(O)N(CH2CH₂OCH3)CH₂(CHOH)4CH₂OH.

10. A mixture of glucose-derived compounds according to Claim 1 which comprises the palm oil chain-length fatty acid amides of an amine selected from the group consisting of HN(CH₂CH2OCH3)CH2(CHOH)4CH₂OH and HN(CH2CH₂CH₂OCH3)- CH₂(CHOH)4CH₂OH.

11. A glucose-derived compound according to Claim 1 which is oleoyl N-(3- methoxypropyl) glucamine.

12. A glucose-derived compound according to Claim 1 which is oleoyl N-(2- methoxyethyl) glucamine.

13. A glucose-derived compound according to Claim 1 which is ricinolyl N-(3- methoxypropyl)glucamine.

14. A glucose-derived compound according to Claim 1 which is ricinolyl N-(2- methoxyethyl)glucamine.

15. A method for laundering fabrics or hard surfaces, comprising contacting said fabrics or hard surfaces with an aqueous solution containing at least 10 ppm of a ClO'Clδ N-alkoxy polyhydroxy fatty acid amide surfactant.

16. A surfactant mixture comprising a member selected from the group of N- alkoxy polyhydroxy fatty acid amides and a member selected from the group consisting of N-alkyl polyhydroxy fatty acid amides.

17. A mixture according to Claim 16 wherein the N-alkoxy polyhydroxy fatty acid amide is selected from the Ciø-C g fatty acid amides of N-(3-methoxypropyl) glucamine and N-(2-methoxyethyl) glucamine and wherein the N-alkyl polyhydroxy fatty acid amides are CiQ-Cig fatty amides of the N-(Cι-C6 alkyl) glucamines.