AU2816199A - Alkoxylation process - Google Patents

Description

Regulation 3.2

AUSTRALIA

PATENTS ACT 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT

(ORIGINAL)

Name of Applicant: Actual Inventors: Huntsman Surfactants Technology Corporation TASDELEN, Essenur Elizabeth CALISKAN, Ece HARRIS, Stuart Charles DAVIES COLLISON CAVE, Patent Attorneys, 1 Little Collins Street, Melbourne, 3000. IP Australia Documents received on: r r r Address for Service: Invention Title:

CD

Alkoxylation process 0 1 4 MAY 1999 -,cn No: Details of Associated Provisional Application No: PP3549/98 15 May 1999 The following statement is a full description of this invention, including the best method of performing it known to us: Q:\OFER\MJC\PP3549.COM 14/5/99 P:\OPER\MJC\EPOXID.PCT 14/5/99 -2- ALKOXYLATION PROCESS The present invention relates to the preparation of alkoxylation products by the catalysed condensation reaction of epoxides (alkylene oxides) and carboxylic esters.

A wide variety of alkoxylation products prepared by the condensation reaction of alkylene oxides with organic compounds having at least one active hydrogen are of industrial significance. The products of condensation of an alkylene oxide, and particularly ethylene oxide or propylene oxide or mixtures thereof, and an alcohol or a phenol are well known surfactants. Other condensation products find application as solvents, and functional fluids.

These alkoxylation products are conventionally prepared by the reaction of at least one active hydrogen compound with an alkylene oxide (epoxide) in the presence of an alkaline or acidic catalyst. An alternative process for alkoxylating organic compounds having at least one active hydrogen utilising a mixed metal catalyst is described in WO93/22266.

Other alkoxylation products which can find use in surfactant and other applications are alkoxylated esters. However, in view of the absence of an active hydrogen atom in the ester linkage, reaction of an ester with alkylene oxide in the presence of an alkaline or acidic catalyst does not result in addition polymerisation of the alkylene oxide into the ester bond.

For this reason esters containing alkylene oxide chains are generally prepared in a two step 0 process which either involves initial reaction of an alkanol with an alkylene oxide to prepare a polyoxyalkylene alkyl ether which is then reacted with a carboxylic acid or ester, or alternatively, by reacting a carboxylic acid with alkylene oxide to produce a polyoxyalkylene acid ester, followed by alkylation.

In recent years there has been some attention focussed on developing catalysts which are capable of alkoxylating esters in a single step. South African Patent Application No. 90/3256 describes the use of calcined hydrotalcites as catalysts for the ethoxylation or propoxylation of fatty acid esters. U.S. Patent No. 5,220,046 describes two types of calcium catalysts useful for alkoxylating methyl esters. U.S. Patent No. 5,374,750 describes the use of a P:\OPER\MJC\EPOXID.PCT 14/5/99 -3catalyst consisting of magnesium oxide and a metal ion selected from Al", Ga 3 In 3 T13+, Co 3 Cs 3 La 3 and Mn 2 in the alkoxylation of monoesters.

It has now been found that salts of the Group Ia, IIa and the rare earth elements and the oxyacids of the Group IVb, Vb and VIb elements may be used as catalysts for introducing alkylene oxide into ester groups.

Accordingly the invention provides a process for inserting alkylene oxide into an ester bond of a carboxylic ester including the step of reacting the carboxylic ester with an alkylene oxide in the presence of a catalytically effective amount of a catalyst comprising the salt of a Group Ia or IIa or rare earth element and an oxyacid of at least one element selected from a Group IVb, Group Vb or Group VIb or mixtures thereof.

The invention also relates to the use of a salt of a Group Ia or IIa or rare earth element and an oxyacid of at least one element selected from a Group IVb, Group Vb or Group VIb or mixtures thereof as a catalyst for inserting an alkylene oxide into an ester bond of a carboxylic ester.

A reference herein to a "Group" refers to the respective group of the periodic table as 20 published in The CRC Handbook of Chemistry and Physics, 75th edition.

As used herein the term "rare earth element" includes scandium, yttrium, lanthanum and S. elements of atomic numbers 58 through to 71 (the lanthanides).

25 Preferably the catalysts used in the process of the invention are selected from compounds of the general formula I: M,(XO) I wherein: P:\OPER\MIC\EPOXID.PCT 14/5/99 -4- M is selected from the group consisting of Li, Na, K, Mg, Ca, Sr, Ba, Sc, Y, La, Ce and Nd and mixtures thereof; X is selected from the group consisting of Ti, Zr, Hf, Nb, Mo, W and mixtures thereof; and m and n are selected to satisfy valency requirements, n being typically 2.0 to 6.0 and m being typically 0.2 to Preferred values for M include K, Ca, Sr, Ba, La, Y and Nd and mixtures thereof.

Preferred values for X include Ti, Zr, Hf, Mo, Nb and mixtures thereof.

Preferred compounds for formula I for use as catalysts in the process of the present invention include barium titanate, barium zirconate, strontium titanate, strontium zirconate, barium strontium titanate, lanthanum titanate, potassium lanthanum titanate, yttrium titanate, lanthanum zirconate, lanthanum hafnate, barium strontium titanate zirconate, barium niobate, lanthanum molybdate and neodymium titanate and calcium titanate.

More preferred compounds of formula I for use as catalysts in the process of the present invention include lanthanum titanate, barium titanate, barium strontium titanate, yttrium 20 titanate, lanthanum zirconate, barium zirconate, lanthanum hafnate, barium strontium titanate zirconate and neodymium titanate. Examples of suitable catalysts and methods for their production include those described in W093/22266, the entire contents of which is incorporated herein by reference. One method of preparing the catalysts of the present invention is known as the "sol-gel" route. This method is well known to those skilled in the 25 art.

The process of the present invention may be applied using a range of alkylene oxides.

Examples of alkylene oxides include ethylene oxide, propylene oxide, the butylene oxides, glycidol, epichlorohydrin, cyclohexene oxide, cyclopentene oxide and styrene oxide. The 30 process of the invention is particularly useful for introduction of ethylene oxide and propylene P:\OPER\MJC\EPOXID.PCT 1415/99 oxide into ester groups.

The process of the present invention may be used to insert alkylene oxide into the ester bond of carboxylic ester compounds. The term "carboxylic ester" refers to an organic compound having an esterified carboxylic acid group. Examples of such compounds include fatty acid esters including mono-, di- and tri-glycerides, alkanoates, such as esters of acetic acid, propionic acid and the like; alkyl esters, such as esters of methanol, aryl esters, such as phthalates and benzoates and esters of aromatic alcohols, such as phenol and the like.

Preferably the carboxylic ester compounds are esters of saturated or unsaturated fatty acids.

The fatty acids are preferably esterified with mono alcohols or polyols having from 1 to 22 carbon atoms and from 1 to 6 hydroxy groups. The polyols may be fully or partially esterified. In a particularly preferred embodiment the carboxylic ester compound is a mono, di or triglyceride of one or more C 8 to C 2 fatty acids which may be the same or different.

Most preferably the ester is a triglyceride.

Examples of suitable fatty acids include those having 8 to 22 carbon atoms of natural or synthetic origin, in particular straight-chain, saturated or unsaturated fatty acids, including mixtures thereof, as can be obtained by lipolysis from animal and/or vegetable fats and oils, i 20 for example from olive oil, coconut oil, palm kernel oil, palm oil, soya oil, sunflower oil, rapeseed oil, cottonseed oil, fish oil, beef tallow and lard. Some specific examples of these fatty acids are caprylic acid, capric acid, lauric acid, lauroleic acid, myristic acid, myristoleic acid, palmitic acid, palmitoleic acid, oleic acid, elaidic acid, arachidic acid, gadoleic acid, behenic acid, brassidic acid and erucic acid. Other fatty acids include methyl-branched, 25 saturated and unsaturated fatty acids having 10 to 22 carbon atoms, and those which can be produced as by-products in the dimerization of the corresponding unsaturated fatty acids, and natural or synthetic hydroxy fatty acids, in particular having 16 to 22 carbon atoms, for example ricinoleic acid or 12-hydroxystearic acid.

30 Examples of mono alcohols and polyols from which suitable fatty acid esters may be P:\OPER\MJC\EPOXID.PCT 14/5/99 -6composed include saturated or unsaturated monoalkanols, such as products of hydrogenation of the abovementioned straight-chain, saturated or unsaturated fatty acids or derivatives thereof, such as methyl esters or glycerides; aliphatic or cyclic alkanols having 1 to 18 carbon atoms, for example methanol, ethanol, propanol, butanol, hexanol and cyclohexanol; including the Guerbet alcohols derived from the abovementioned monoalkanols, and polyols, such as ethylene glycol, 1,2-propylene glycol, 1,2-butylene glycol, neopentyl glycol, glycerol, diglycerol, triglycerol, tetraglycerol, trimethylolpropane, di-tri-methylolpropane, pentaerythritol, di-pentaerythritol, and sugar alcohols, such as sorbitan, glucose, mannitol, fructose and sucrose.

The amount of catalyst used in the process of the present invention depends to a large extent on the specific catalyst used and the carboxylic ester compound and the alkylene oxide which are being reacted. Hence the amount of catalyst used is that amount which is catalytically effective in carrying out the reaction at the rate and with the selectivity desired. Typically the catalyst level may vary in the range of from 10 ppm to 10 percent by weight based on the weight of the carboxylic ester compound. Preferably the catalyst is in the range of from 0.1 to 10% by weight of the carboxylic ester compound.

In a preferred embodiment the process of the current invention for inserting alkylene oxide 20 into the ester bond of a carboxylic ester comprises the steps of: adding a catalyst to the carboxylic ester in a reactor, heating and pressurising the reactor containing said ester, supplying alkylene oxide to said ester and catalyst at a process temperature of between 25 50 and 250°C and at a process pressure of between 300 and 700 kPa, and isolating the reaction products.

The invention also provides an alkoxylated ester when prepared in accordance with the processes hereinbefore described.

P:\OPER\MJC\EPOXID.PCT 14/5/99 -7- The temperature which the process of the present invention is carried out will depend upon a number of factors including the heating and cooling facilities available in the reaction vessel and the pressure at which the reaction vessel may be operated. However, in general, a temperature in the range of from 50 to 2500C is satisfactory and a temperature in the range of from 80 to 200'C may be preferred.

The pressure at which the process of the present invention is carried out will depend to a large extent on the alkylene oxide used and the temperature at which the reaction is carried out.

However, preferably the process of the present invention is carried out at a pressure above atmospheric pressure. In practice a reaction pressure of between 300 kPa and 700 kPa with an alkylene oxide partial pressure of between 100 and 500 kPa has been found to be suitable.

The reaction time required for the process of the present invention is dependent upon the nature of the carboxylic ester compound and the nature of the alkylene oxide used, the reaction temperature and pressure and the catalyst and quantity of the catalyst used. In practice, reaction times may vary from 15 minutes to approximately 20 hours.

The catalysts used in the present invention may be in the form of finely divided solids.

Therefore, if desired, after the reaction has been completed and the product cooled, the i 20 catalyst may be recovered from the final product by any means suitable for the removal of finely divided solid from a reaction mixture. For example, depending on the size of the o **finely divided solid and the viscosity of the product, the catalyst may be removed by filtration, centrifugation, extraction or suitable like means.

.9..o It should be noted, that although not essential for the process of the present invention, the catalyst used for the process of the present invention may also contain other components including impurities resulting from the preparation of the catalyst and introduced components which may be added to promote or modify catalyst activity and/or selectivity.

P:\OPER\MJC\EPOXID.PCT 14/5/99 -8- The invention will now be described with reference to the accompanying examples which illustrate some preferred embodiments of the present invention. However it is to be understood that the particularity of the following description of the invention is not to supersede the generality of the preceding description.

EXAMPLES

Example 1: Methyl laurate ethylene oxide Lanthanum titanate (10.41g) was added to methyl laurate (303g) and the mixture was transferred to a 2 litre autoclave reactor. The contents of the reactor were heated to 110°C under vacuum for one hour to drive off water. The mixture was heated to 160 C and the autoclave pressurised to 40 kPa with nitrogen. Ethylene oxide was then introduced into the reactor to a total pressure of 400 kPa. Ethoxylation commenced immediately. Additional ethylene oxide was supplied on demand to maintain a pressure of 400 kPa and temperature maintained between 160°C-170°C. A total of 186 grams of ethylene oxide was taken up over a period of 12 minutes. The contents of the reactor were maintained at temperature for an additional 30 minutes to consume unreacted ethylene oxide. The product was analysed by 20 GLC techniques and found to have an average adduct number of 3.1.

Further ethoxylation of this product (363g) was carried out following the above general procedure. A total of 230 grams of ethylene oxide was taken up over a period of 24 minutes.

The reactor was maintained at temperature for an additional 30 minutes to consume unreacted 25 ethylene oxide. The product was analysed by GLC techniques to have an average adduct number of 6.3, while the amount of unreacted methyl laurate was 4%.

Example 2: Ethyl Caprylate ethylene oxide Example 2: Ethyl Caprylate ethylene oxide P:\OPER\MJC\EPOXID.PCT 14/5/99 -9- Under the conditions detailed in Example 1, ethyl caprylate was ethoxylated using the lanthanum titanate catalyst. A total of 306 grams of ethyl caprylate and 10.3 grams of lanthanum titanate were used. As a reaction temperature of 160-170°C, a total of 221 grams of ethylene oxide was taken up over 12 minutes. The product was analysed by GLC techniques and found to have an average adduct number of Further ethoxylation of this product (360 grams) was carried out. A total of 261 grams of ethylene oxide was taken up over a period of 35 minutes. The product was analysed by GLC techniques to have an average adduct number of 5.9, while the amount of unreacted ethyl laurate was found to be 27%.

Example 3: Isopropyl myristate ethylene oxide Under the conditions detailed in Example 1, isopropyl myristate was ethoxylated using the lanthanum titanate catalyst. A total of 208 grams of isopropyl myristate and 5.71 grams of lanthanum titanate were used. At a reaction temperature of 160-170oC, a total of 102 grams of ethylene oxide was taken up over 18 minutes.

20 Further ethoxylation of this product (258 grams) was carried out. A total of 141 grams of ethylene oxide was taken up over 40 minutes. GLC techniques indicated that the amount of unreacted isopropyl myristate was 93 25 Example 3: Olive oil ethylene oxide Preparation Under the conditions detailed in Example 1, a commercial olive oil was ethoxylated using the lanthanum titanate catalyst. A total of 302 grams of olive oil and 16.6 grams of lanthanum titanate were used. At a reaction temperature of 160-170oC, a total of 140 grams of ethylene 30 oxide was taken up over 2 hours and 20 minutes. The resultant ethoxylate was found to have P:\OPER\MJC\EPOXID.PCT 1415/99 a saponification number of 125.

Further ethoxylation of this product (355 grams) was carried out. A total of 130 grams of ethylene oxide was taken up over a period of 15 minutes. The ethoxylate was found to have a saponification number of 96. Nuclear magnetic resonance techniques indicated complete conversion of the triglyceride.

The above process was repeated to produce a range of olive oil ethoxylates with nominally 20, 30, 40, 50, 60 and 100 units of ethylene oxide (EO) added.

In the early stages of the ethoxylation reaction, ethylene oxide uptake was quite slow. For the first few EO units inserted the rate was in the order of -0.003g EO/gRM/min whereas beyond the induction period, rates increased markedly (up to -O.OlgEO/gRM/min).

(RM raw material).

Catalyst residues were removed from the products at 70 0 C by stirring in an amount of Speedflow Dicalite filter aid from Grefco Inc. and filtering the slurry under high vacuum.

Filtration proceeded smoothly for the 10-40 EO/olive oil adducts, however, for the products of higher viscosity 50 EO/olive oil), the filter cake became blocked by a viscous plug of 20 catalyst swelled with ethoxylate. In these instances, the catalyst residues were allowed to settle to the bottom of the molten ethoxylate at 70°C, and then the clear catalyst free upper layer was decanted off and filtered in the normal manner. The olive oil 100 EO ethoxylate was not filtered because the viscosity was quite high even at 70°C and the catalyst residues failed to settle.

Characterisation Analyses of the olive oil ethoxylates with 10, 20 or 30 EO units inserted, by 'H and "C NMR were consistent with products in which ethylene oxide had been inserted into each ester bond.

30 It was also shown for the 10 mole adduct, that virtually no raw material (olive oil) remained P:\OPER\MWC\EPOXID.PCT 14/5/99 11 in the mixture and the insertion had occurred in all three ester bonds.

An OHV (hydroxyl value) analysis of an olive oil 20EO ethoxylate gave a very low hydroxyl value, consistent with a product prepared by ester insertion. Alternate processes which generate free OH, PEG formulation and ester cleavages, appeared to be unimportant.

The presence of minor amounts of glycerol mono-esters, glycerol diesters and their ethoxylation products were probably the major contributors to the hydroxyl value.

The primary method for raw molecular weight determination for the ethoxylation products was saponification value. As expected the SAP values of the products decreased as the amount of EO inserted was increased (Table By taking these results in combination with the 'H NMR results and hydroxyl values, it was evident that the build process was insertion.

Table 1 Product SAP Value Calculated No of Appearance at Pour EO units inserted 25 0 C Point Olive oil 10EO 125 12.1 Soft yellow paste 33 Olive oil 20EO 95.7 21.4 Yellow paste 34 Olive oil 30EO 81.0 28.7 Hard yellow paste 36 Olive oil 40EO 64.7 40.6 Off-white solid 43 20 Olive oil +50EO 55.3 50.6 While solid 44 Olive oil 60EO 45.3 64.5 White solid 39 Olive oil 100EO 30.1 107.3 White solid 51 In terms of physical form at 25°C, the olive oil ethoxylates ranged from a soft yellow paste for the olive oil 10EO adduct, and progressively became harder materials with lighter colours with an increasing number of EO units added. The most highly ethoxylated product, the olive oil 100EO ethoxylate, was an off-white waxy solid. The pour points of the olive oil increased with increasing amounts of EO added (Table 1).

9r 9* 9 9 9 *9 9* 9 9.

a P:\OPER\MJC\EPOXID.PCT 14/5/99 -12- The olive oil ethoxylates with high levels of ethoxylation were sufficiently soluble in water w/v) for determination of aqueous cloud points. However, for the olive oil ethoxylates with 40-60 EO units added, 25% DEGBE cloud points in the range 57-66 C could be determined using the mixed solvent system (H 2 0/DEGBE=3/1).

Table 2 Cloud Point oC Ethoxylate Ethoxy e 1% aqueous 25% DEGBE Solution Olive oil 40EO 57-59 Olive oil 50EO 58-60 Olive oil 60EO 45 66 Olive oil 100EO 74 Comparison of olive oil ethoxylates with other surfactants The aqueous solution properties of the olive oil ethoxylates with 60 or 100 moles of EO added were found to show some similarities to castor oil ethoxylates and fatty acid ethoxylates with high EO contents, i.e. 60 w%.

Table 3 Surface Tension mN/m Foam Heights (cm) Tape wetting (s) w% Ethoxylate EO 1.0% 0.1% 0.01% 1.0% 0.1% 0.01% 1% 0.1% 0.01% I F I F I F Olive oil 76.5 39.8 41.9 51.3 12.4 11.8 4.5 2.8 2.2 1.9 69 198 243 Olive oil 84.4 44.5 45.9 53.3 13.2 12.9 4.3 3.8 1.9 1.7 184 229 312 25 100EO TERIC C12' 61.8 41.4 42.0 46.4 11.9 11.2 5.7 3.7 2.5 1.4 31 66 127 TERIC SF15 2 70.0 40.0 40.7 42.5 14.0 10.0 6.0 5.0 3.0 1.0 27 40 102 TERIC OF83 55.7 33.6 33.6 33.8 4.0 3.5 1.0 0.8 0.5 0.2 25 60 277 30 castor oil 36EO 2 castor oil 54EO 3 oleic acid 8EO The present invention allows the preparation of useful surfactants, emulsifiers and the like from naturally occurring esters, such as the glycerol triesters. These glycerol triesters, such as olive oil, are a cheap and readily available source of hydrophobe which, upon alkoxylation, provide a unique range of these products. By comparison of the properties of some olive oil S. S S S

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P:\OPER\MJC\EPOXID.PCT 14/5/99 13 ethoxylates with known surfactants it is evident that they may be especially suitable for use in crop oil emulsifiers (eg. preparation of emulsifiable concentrates), personal care applications (eg. preparation of low irritant products based on natural raw material) and as lubricants (eg. anti static processing lubricants).

It is clear from the examples above that the ability of mono-alkanol fatty acid esters to take up ethylene oxide according to the method of the invention decreases substantially as the size of the alkyl group increases. In this regard in the reaction of the isopropyl ester with ethylene oxide 93% of the starting material remained unreacted. It is therefore surprising and unexpected on the basis of the results for ethyl and isopropyl esters that alkoxylation of glycerol esters would proceed to such a significant extent.

Those skilled in the art will appreciate that the invention described herein is susceptible to variations and modifications other than those specifically described. It is to be understood that the invention includes all such variations and modifications. The invention also includes all of the steps, features, compositions and processes referred to or indicated in this specification, individually or collectively, and any and all combinations of any two or more of said steps or features.

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Claims (14)

1. Use of a salt of a Group Ia or IIa or rare earth element and an oxyacid of at least one element selected from a Group IVb, Group Vb or Group VIb or mixtures thereof as a catalyst for inserting an alkylene oxide into an ester bond of a carboxylic ester.

2. Use according to claim 1 wherein the catalyst is selected from compounds of the general formula I: MXO) I wherein: M is selected from the group consisting of Li, Na, K, Mg, Ca, Sr, Ba, Sc, Y, La, Ce and Nd and mixtures thereof; X is selected from the group consisting of Ti, Zr, Hf, Nb, Mo, W and mixtures thereof; and m and n are selected to satisfy valency requirements. 20 3. Use according to claim 2 wherein n is 2.0 to

4. Use according to claim 2 or claim 3 wherein m is 0.2 to 9* A process for inserting alkylene oxide into an ester bond of a carboxylic ester 25 including the step of reacting the carboxylic ester with an alkylene oxide in the S* presence of a catalytically effective amount of a catalyst comprising the salt of a Group Ia or IIa or rare earth element and an oxyacid of at least one element selected from a Group IVb, Group Vb or Group VIb or mixtures thereof.

6. A process according to claim 5 wherein the catalyst is selected from compounds of the P:\OPER\MJC\EPOXID.PCT 14/5/99 general formula I: M,(XO) I wherein: M is selected from the group consisting of Li, Na, K, Mg, Ca, Sr, Ba, Sc, Y, La, Ce and Nd and mixtures thereof; X is selected from the group consisting of Ti, Zr, Hf, Nb, Mo, W and mixtures thereof; and m and n are selected to satisfy valency requirements.

7. A process according to claim 6 wherein n is 2.0 to

8. A process according to claim 6 or claim 7 wherein m is 0.2 to

9. A process according to any one of claims 6 to 8 wherein M is selected from K, Ca, Sr, Ba, La, Y and Nd and mixtures thereof.

10. A process according to any one of claims 6 to 9 wherein X is selected from Ti, Zr, Hf, Mo and mixtures thereof.

11. A process according to any one of claims 6 to 10 wherein the catalyst is selected from 25 barium titanate, barium zirconate, strontium titanate, strontium zirconate, barium strontium titanate, lanthanum titanate, potassium lanthanum titanate, yttrium titanate, lanthanum zirconate, lanthanum hafnate, barium strontium titanate zirconate, barium niobate, lanthanum molybdate and neodymium titanate and calcium titanate. 30 12. A process according to any one of claims 6 to 11 wherein the catalyst is selected from P:\OPER\MJC\EPOXID.PCT- 14/5/99 -16- lanthanum titanate, barium titanate, barium strontium titanate, yttrium titanate, lanthanum zirconate, barium zirconate, lanthanum hafnate, barium strontium titanate zirconate and neodymium titanate.

13. A process according to any one of claims 6 to 12 wherein the catalyst is lanthanum titanate.

14. A process according to any one of claims 6 to 13 wherein the alkylene oxide is selected from ethylene oxide and propylene oxide. A process according to any one of claims 6 to 14 wherein the carboxylic ester is selected from fatty acid esters, alkyl esters, alkanoates, aryl esters and esters of aromatic alcohols.

16. A process according to claim 15 wherein the carboxylic ester is a fatty acid ester.

17. A process according to claim 16 wherein the fatty acid ester is a mono-, di- or triglyceride. 20 18. A process for inserting alkylene oxide into the ester bond of a carboxylic ester comprising the steps of: adding a catalyst to the carboxylic ester in a reactor, o* heating and pressurising the reactor containing said ester, 25 supplying alkylene oxide to said ester and catalyst at a process temperature of between and 250°C and at a process pressure of between 300 and 700 kPa, and isolating the reaction products.

19. An alkoxylated ester when prepared in accordance with a process according to any one 30 of claims 6 to 18.