IE52829B1 - Polyether thickeners for aqueous systems containing additives for increased thickening efficiency - Google Patents

Description

This invention relates to thickeners for aqueous systems based upon polyethers of high molecular weight.

Polymeric water-soluble thickening agents are widely used for many purposes. Commercially available polymeric thickeners differ widely in chemical composition. The diversity of available thickening agents is an indication that not all are equally useful. It is not unusual to find some thickening agents which perform well in a certain environment and not at all in another environment.

In fact, in some uses, no one thickening agent is completely satisfactory and there is a continual need and a continuing search for new thickening agents to satisfy many unmet needs. For instance, various cellulose derivatives or other water-soluble polymers such as sodium polyaerylates, poly15 acrylamides and polyethylene glycol fatty acid diesters are representative thickening agents. The polyethylene glycol fatty acid diesters are widely used for textile printing emulsions, cosmetic emulsions, and aqueous pigment suspensions. These esters suffer from the defect that they are not resistant to hydrolysis in an acid or alkaline medium so that under such conditions the thickening effect initially obtained is gradually reduced.

Polyoxyalkylene compounds, including high molecular weight materials are well known for use as surface-active agents, as disclosed in U.S. 2,674,619. These compositions can be prepared at high molecular weights, for instance, SS839 - 3 up to 25>000 for use as aqueous thickeners. Xt is known that liquid polyoxyalkylenes can be obtained by utilizing a mixture of ethylene oxide and another lower alkylene oxide in an oxide ratio of from 75 to 90 percent ethylene oxide to 10 to 25 percent other lower alkylene oxides such as 1,2-propylene oxide, as taught in U.S. 2,425,755. The polyethers of the prior art having high thickening efficiency are generally those having the highest molecular weights reasonably obtainable under commercial conditions with price considerations being a limiting factor. Because the preparation of high molecular weight polyethers require a disproportionately longer processing time to produce, it would be desirable to prepare high efficiency thickeners utilizing lower molecular weight polymers. in U.S. 3,538,033, there are disclosed polyoxyalkylene derivatives of diepoxides having thickening properties. The thickener compositions disclosed are useful for thickening aqueous systems and are prepared by reacting a diepoxide compound having at least 12 carbon atoms with an alkylene oxide adduct containing from 100 to 250 moles of ethylene oxide units.

In U.S. 3,829,506, there are disalosed biodegradable surface-active agents having good foam properties and foam stabilizing characteristics prepared by copolymerizing ethylene oxide alone or with another lower alkylene oxide and an alpha olefin oxide in the presence of a polyhydric alcohol. Molecular weights of 400 to 6000 are claimed but there is no indication that the compositions are useful as thickening agents for aqueous systems.

In U.S. 3,475,499, there is disclosed the preparation of glycols and glycol ethers by reacting with water 1,2-epoxides having 3 to 30 carbon atoms. The compositions are disclosed as useful in the preparation of detergents.

High molecular weight polyether block polymers are disclosed in U.S. 3,535,307. Such compositions have molecular weights of about 2000 to about 25,000 and are useful in the preparation of polyurethanes. - 4 Polyether-based thickeners are disclosed which comprise heteric, block, or homopolymer polyethers prepared by reacting ethylene oxide or ethylene oxide and at least one lower alkylene oxide having 3 to 4 carbon atoms in the presence of an active hydrogen-containing compound initiator and at least one alpha-olefin oxide having ahout 12 to about 18 carbon atoms. The alpha-olefin oxide can alternatively be reacted sequentially so as to cap the previously formed polymer. Improved thickening efficiency of said polyethers can be obtained by admixture with at least one of an ethoxylated phosphate ester or said phosphate ester and a water-soluble amine. The thickeners of the invention are particularly suited to use in aqueous hydraulic fluids where viscosity stability under high shear and elevated temperature conditions is desirable.

Polyether thickening agents having greatly improved thickening efficiency over prior art high molecular weight polyethers based upon the reaction of ethylene oxide with an active hydrogen-containing initiator having at least 2 active hydrogens in combination with a lower alkylene oxide containing 3 to 4 carbon atoms can be prepared by modifying such conventional polyether thickening agents with an alphaolefin oxide having about 12 to about 18 carbon atoms or mixtures thereof. Polyether compositions and processes are disclosed in US - A.- 4411819. Whether said alpha-olefin oxide is incorporated in the modified-polyether by copolymeriza tion to produce a heteric polyether or by capping an ethylene oxide homopolymer or heteric or block polyethers, improved thickening efficiency without reduction in viscosity stability under high shear conditions can be obtained. Preferably, said heteric or block polyethers are capped with an alpha-olefin oxide. A further improvement in thickening efficiency can be obtained by combining the above-described alpha-olefin oxidemodified polyethers with at least one of an ethoxylated aliphatic phosphate ester or said ester and a water-soluble amine. 53828 - 5 The preparation of polyethers is well known in the art. Generally, polyethers are prepared utilizing a lower alkylene oxide, an active hydrogen containing compound, and an acid or basic oxyalkylation catalyst in the presence r> of an inert organic solvent at elevated temperatures in the range of about 50°C. to 150°C. under an inert gas pressure generally from about 1 bar to 10 bars.

Any suitable prior art alkaline oxyalkylation catalyst can be used in the preparation of the polyethers used herein. These include, for example, strong bases, such as sodium hydroxide, sodium methoxide, potassium hydroxide, and the like? salts of strong bases with weak acids, such as sodium acetate, sodium glycolate, and the like and quaternary ammonium compounds, such as benzyl dimethyl cetyl ammonium compounds and the like. The concentration of these catalysts in the reaction mixture is not critical and may vary from about 0.1 percent to 5 percent by weight of the initiator compound.

An inert organic solvent may be utilized in the above-described procedures. The amount of solvent used is that which is sufficient to provide a suitable reaction medium and is generally, on a molar basis, in excess of the total amount of the reactants. Examples of suitable solvents include aliphatic hydrocarbons, such as hexane, heptane, isoheptane; aromatic hydrocarbons, such as benzene, toluene, xylene? chlorinated hydrocarbons, such as carbon tetrachloride, ethylene dichloride, propylene dichloride; and oxygenated hydrocarbons, such as diethyl ether, dimethyl ether, anisole, and the like.

A useful copolymer polyether is prepared by mixing ethylene oxide and at least one lower alkylene oxide having 3 to 4 carbon atoms with a low molecular weight active hydrogen-containing compound initiator having 2 to 6 active hydrogen atoms such as a polyhydric alcohol, containing from 2 to 10 carbon atoms and from 2 to 6 hydroxyl groups and from about 5.0 mole to 15.0 moles of an alpha-olefin oxide S2B29 - 6 per mole of alcohol, said oxide having from 12 to 18 carbon atoms; heating said mixture to a temperature in the range of about 50°C. to 150°C., preferably from 80*C. to 130*C., under an inert gas pressure preferably from about 2 bars to bars. A mixture of ethylene oxide and other alkylene oxides having from three to four carbon atoms is used in said mixture in an amount so that the resulting polyether product will contain at least 10 percent by weight, preferably about 70 percent to 99 percent by weight ethylene oxide.

Said mixture is maintained at a temperature and pressure in said range for a period of about one hour to ten hours, preferably one to three hours. Alternatively, ethylene oxide homopolymers or block or heteric polymers of ethylene oxide and at least one lower alkylene oxide having 3 to 4 carbon atoms can be prepared as intermediates. These are then capped with said alpha-olefin oxide to prepare the thickeners of this invention. If desired, a catalyst can be added to the reaction mixture prior to the ethylene oxide addition. Alkaline catalysts such as potassium hydroxide or acid catalysts such as boron trifluoride are useful, as is well established in the art. The heteric copolymers can be liquids; the ethylene oxide homopolymers are solids; and the block copolymers are semi-solids at ambient temperatures.

As is well known in the art, polyethers are prepared utilizing an initiator compound which contains a reactive (or active) hydrogen atom. The term reactive hydrogen atom is well known and clearly understood by those skilled in the art. However, to remove any possible ambiguity in this regard, the term reactive hydrogen atom, as used herein and in the appended claims, includes any hydrogen atom fulfilling the following two conditions: 1. It is sufficiently labile to open the epoxide ring of 1,2-propylene oxide, and 2. It reacts with methyl magnesium iodide to liberate methane In the classical Zerewitinoff reaction (see Niederle and Niederle, Micromethods of Quantitative Organic Analysis, p. 263, John Wiley and Sons, New York City, 1946). 52828 The reactive hydrogen atoms which will fulfill the above two conditions are normally activated by being a member of a functional group containing an oxygen atom, e.g., a hydroxyl group, a phenol group, a carboxylic acid group; a basic nitrogen atom, e.g., an amine group, a hydrazine group, an imine group, an amide group, a guanidine group, a sulfonamide group, a urea group, a thiourea group; or a sulfur atom, e.g., a mercaptan, a thiophenol, a thiocarboxylic acid, hydrogen sulfide. Alternatively, certain hydrogen atoms may be activated by proximity to carbonyl groups such as those found in cyanoacetic esters, acetoacetic esters, malonic esters, as is well known in the art. Generally, polyhydric alcohol initiators selected from the alkane polyols, alkene polyols, alkyne polyols, aromatic polyols, and oxyalkylene polyols are useful initiators. Specific examples of base compounds which may be used in preparing the polyoxy-alkylene polymers include ethylene glycol, 1.3- butylene glycol, oxalic acid, mono-, di-, and triethanolamine, butylamine, aniline, resorcinol, diethylmalonate, glycerol, butane diol, oxalic acid, diethylmaleate, pentaerythritol, sucrose, ethylene diamine, bisphenol A, hydroquinone, etc.

Of the alkane polyols such as ethylene glycol, propylene glycol, 1,4-butanediol, 1,2-butanediol, trimethylol propane, glycerol, 2,3,5,6-hexane tetrol, sorbitol, pentaerythritol, glucose and the like, polyhydric alcohols having 2 to 10 carbon atoms and from 2 to hydroxy groups are preferred initiators. Alkene polyols having 2 to 10 carbons and from 2 to 6 hydroxyl groups are also useful such as 2-butene-1,4-diol, 2-hexene-l,4,6-triol, 3-heptene-l,2,6,7-tetrol, 1,5-hexadiene3.4- diol and the like as well as the alkyne polyols such as 2-butyne-l,4-diol, 2-hexyne-1,4,6-triol, 4-octyne-l,2,7,8tetrol and the like. The oxyalkylene polyols, such as diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, tripropylene glycol, and the like are also useful. 2829 - 8 The heteric or block copolymers useful in the Invention which are capped, i.e., copolymerized with an alpha-olefin oxide having 12 to 18 carbon atoms are mixtures with ethylene oxide of lower alkylene oxides having 3 to 4 carbon atoms. Generally, the proportion of ethylene oxide is at least about 10 percent by weight and preferably is 70 to 99 percent by weight of the mixture of ethylene oxide and the alkylene oxide having 3 to 4 carbon atoms. The lower alkylene oxides referred to are propylene oxide and the butylene oxides such as 1,2butylene oxide and 2,3-butylene oxide and tetrahydrofuran.

The proportion of lower alkylene oxides having 3 to 4 carbon atoms utilized in combination with ethylene oxide is generally less than 90 percent by weight of the mixed copolymer and preferably is 30 to 1 percent by weight thereof. Generally, useful polymers have a molecular weight of 1000 to 75,000, preferably 1000 to 40,000.

The alpha-olefin oxides which are utilized to modify the polyether polyols of the prior art are those oxides containing 12 to 18 carbon atoms and the commercially available mixtures thereof. The amount of alpha-olefin oxide required to obtain the more efficient polyether thickening agents of the invention is 1 to 20 percent by weight of the total weight of the polyether thickeners of the invention. This amount of alphaolefin oxide based upon the molar amount of active hydrogencontaining initiator compound is 5.0 mole to 15.0 moles of alpha-olefin oxide per mole of di- or trifunctional active hydrogen-containing initiator. Preferably, the alpha-olefin oxide contains a mixture of 14 to 16 carbon atoms and linear alkyl chains. Examples of useful alphaolefin oxides are those commercially available under the trademark VIK0L0X. since the preparation of heteric and block copolymers of alkylene oxides are well known in the art, further description of the preparation of heteric and block copolymers of mixed lower alkylene oxides is unnecessary. Further details of the preparation of heteric copolymers of lower alkylene oxide can be obtained in U.S. 3,829,506 .

Further information on the preparation of block copolymers of lower alkylene oxides can be obtained in U.S. 3,535,307.

Alternatively to the use of the above-described alpha-olefin oxides to modify high molecular weight polyethers, it is possible to substitute glycidyl ethers which can be prepared by reaction of an alcohol having 12 to about 18 carbon atoms with epichlorohydrin in accordance with the chlorohydrin in accordance with the teachings of U.S. 4,086,279 and references cited therein.

The useful water-soluble amines which act synergistically in combination with the ethoxylated phosphate esters in providing increased thickening efficiency of the above-described polyethers modified with alpha-olefin oxides are the water-soluble aliphatic, aromatic and cyclo-aliphatic amines including alkanol amines. Representative examples include methylamine, dimethylamine, trimethylamine, ethyl20 amine, diethylamine, triethylamine, n-propylamine, di-npropylamine, tri-n-propylamine, isopropylamine, n-butylamine, isobutylamine, secondary butylamine, tertiary butylamine, cyclohexylamine, benzylamine, alpha-phenylethylamlne, beta-phenylethylamine, ethylenediamine, tetramethylenediamine, hexamethylenediamine, tetramethylammonium hydroxide, morpholine, N-methyl morpholine, N-ethyl morpholine, dimethylaminopropylamine, Ν,Ν-dimethylethanolamine, alpha- and gamma-picoline, piperazine, isopropylaminoethanol, N,Ndimethylcyclohexylamine, 2-amino-2-methyl-l-propanol.

The ethoxylated phosphate ester useful either alone or in combinations with the above-described watersoluble amines in providing increased efficiency of the above-described alpha-olefin epoxide-modified polyether polyol are those phosphate esters selected from the group consisting of: II RO-(EO) —P-OX n I OX and RO-(EO) — —(EO) —OR η n and mixtures thereof, wherein EO is ethylene oxide; R is selected from the group consisting of linear or branched chain alkyl groups having 6 to 30 carbon atoms, preferably 8 to 20 carbon atoms, aryl or alkylaryl groups wherein the alkylaryl groups have 6 to 30 carbon atoms, preferably 8 to 18 carbon atoms, and X is selected from the group consisting of the residue of ammonia or an amine, hydrogen and an alkali or alkaline earth metal or mixtures thereof and n is a number from 1-50. Metals such as lithium, sodium, potassium, rubidium, cesium, calcium, strontium and barium are examples of X.

The phosphate ester compositions utilized in the compositions of the invention are more fully disclosed in U.S. 3,044,056 and U.S. 3,004,057.

In general, the phosphate esters employed are obtained by esterifying one mole of p2°5 with 2 to 4.5 moles of a nonionic surface active agent characterized as a condensation product of at least one mole of ethylene oxide with one mole of a compound having at least 6 carbon atoms and a reactive hydrogen atom. Such nonionic surface active agents are well known in the art and are generally prepared by condensing a polyglycol ether containing a suit25 able number of alkenoxy groups or a 1,2-alkylene oxide, or substituted alkylene oxide such as a substituted propylene oxide, butylene oxide or preferably ethylene oxide with an organic compound containing at least 6 carbon atoms and a reactive hydrogen atom. Examples of compounds containing a reactive hydrogen atom are alcohols, phenols, thiols, primary and secondary amines, and carboxylic and sulfonic acids and their amides. The amount of alkylene oxide or equivalent condensed with the reactive chain will depend primarily upon the particular compound with which it is condensed. Generally, an amount of alkylene oxide or S2829 - 11 equivalent should be employed which will result in a condensation product containing 20 to 85 percent by weight of combined alkylene oxide. However, the optimum amount of alkylene oxide for attainment of the desired hydrophobichydrophilic balance may be readily determined in any particular case by preliminary test and routine experimentation.

The nonionic surface active agents used are preferably polyoxyalkylene derivatives of alkylated and polyalkylated phenols, multi-branched chain primary aliphatic alcohols having the molecular configuration of an alcohol produced by the oxo process from a polyolefin of at least 7 carbon atoms, and straight chain aliphatic alcohols of at least 10 carbon atoms. Examples of these derivatives and other suitable nonionic surface active agents which may be phosphated in accordance with the present invention are included below. In this list, EO means ethylene oxide and the number preceding same refers to the number of moles thereof reacted with one mole of the given reactive hydrogen containing compound.

Nonylphenol + 9 EO Nonylphenol + 2 EO Dinonylphenol + 7 EO Dodecylphenol + 18 EO Castor oil + 20 EO Tall oil* + 18 EO Oleyl alcohol + 4 EO Oleyl alcohol + 20 EO Lauryl alcohol + 4 EO Lauryl alcohol + 15 EO Hexadecyl alcohol + 12 EO Hexadecyl alcohol + 20 EO Octadecyl alcohol + 20 EO Oxo tridecyl alcohol: (From tetrapropylene) + 7 EO (From tetrapropylene) + 10 EO (From tetrapropylene) + 15 EO Dodecyl mercaptan + 9 EO * Tall oil is a mixture of rosin acids, fatty acids and other materials obtained by acid treatment of the alkaline liquors from the digesting of pine wood. - 12 Rosin amine + 32 EO Coconut fatty acid amine + 7 EO Cocoa fatty acid + 10 EO Dodecylbenzene sulfonamide + 10 EO Decyl sulfonamide + 6 EO Oleic acid + 5 EO Propylene glycol (30 oxypropylene units) + 10 EO Increased thickening efficiency of the alphaolefin oxide modified polyether disclosed above is preferably obtained by utilizing the aromatic or aliphatic ethoxylated phosphate ester described above alone or in mixtures thereof with a water-soluble amine, as described above. Surprisingly, greatly improved thickening efficiency can be obtained utilizing relatively minor amounts of either said mixture or the phosphate ester alone. Generally, at least about 0.5 percent by weight of either of said phosphate ester or said mixture of phosphate ester and water-soluble amine are utilized to provide the improved thickening efficiency with the above-described alpha-olefin oxide-modified polyether.

A mixture of 20 to 50 percent of said amine with 80 to 50 percent of said phosphate, ester is generally used. Preferably, a mixture of 30 to 40 percent by weight of said amine and 70 to percent by weight of said phosphate ester, all based upon the total weight of the mixture of the modified polyether and phosphate ester and amine additives, is used. to 35 percent by weight based upon the total weight of said polyether-based thickener is used of said mixture of said phosphate ester and said water-soluble amine or said phosphate ester. An effective thickening proportion of polyether is utilized in thickening aqueous systems, generally 5 percent to 50 percent by weight, preferably 10 percent to 20 percent by weight. 35 The following examples will illustrate the prepara· tion of the alpha-olefin oxide-modified polyethers and mixtures thereof with the phosphate ester and amine additives - 13 of the invention. Where not otherwise specified throughout this specification and claims, temperatures are given in degrees centigrade and parts, percentages and proportions are by weight.

Example 1 (Control or Comparative Example) A conventional polyether derived from ethylene oxide and 1,2-propylene oxide in the ratio of 75 percent ethylene oxide and 25 percent 1,2-propylene oxide was prepared by reaction with trimethylol propane in two stages in a stainless steel autoclave. An intermediate product was first prepared by reacting a mixture of trimethylol propane, potassium hydroxide, 1,2-propylene oxide, and ethylene oxide for a period of 18 hours at 120°C. The cooled liquid product was discharged into a glass container.

The final product was prepared by reacting this intermediate product with 1,2-propylene oxide and ethylene oxide under a nitrogen atmosphere at 115’C. for 22 hours.

The reaction mixture was then cooled and the viscous liquid product transferred to a glass container. The product had a molecular weight of about 23,000.

Example 2 Into a 7.57 1 (two-gallon) stainless steel mixer there was charged 3400 grams of the copolymer prepared in Example 1.

The contents of the mixer were blanketed with nitrogen and then heated by steam utilizing an external jacket on the mixer. There was then added 6.8 grams of sodium and the mixture was stirred while the reaction was allowed to continue. After 3.5 hours, 34 grams of a mixture of alpha-olefin oxides having an aliphatic chain length of 15 to 18 carbon atoms sold under the trademark VIKOLOX 15-18 by the Viking Chemical Company, was added at once. The stirring and heating was continued for another 43 hours before the reaction mixture was cooled and the viscous product transferred to a glass container.

Example 3 A liquid heteric copolymer of 80 percent by weight ethylene oxide, 15 percent by weight 1,2-propylene oxide and - 14 5 percent by weight of an alpha-olefin oxide having an aliphatic carbon chain length of 15 to 18 carbon atoms sold under the trademark VIKOLOX 15-18 was prepared according to the following procedure.

A glass flask was charged with 1410 grams of the intermediate copolymer prepared in Example 1 and heated to 105°C. while under a nitrogen atmosphere. While stirring the contents of the flask, there was added 10.2 grams of sodium and the mixture reacted for a period of 24 hours.

The intermediate product obtained was cooled to room temperature prior to further use. Thereafter a 250 milliliter centrifuge bottle was charged with 100 grams of the intermediate product prepared above together with 3.3 grams of propylene oxide and 19 grams of ethylene oxide. The contents of the bottle were mixed at room temperature and then the bottle was stopped with a teflon covered rubber stopper and the bottle was placed in a steam bath for 24 hours. The second intermediate product was cooled to room temperature before further use. To the centrifuge bottle above containing the second intermediate product obtained above, there was added 2.5 grams of an alpha-olefin oxide having an aliphatic carbon chain length of 15 to 18 carbon atoms sold under the trademark VIKOLOX 15-18 together with 3.3 grams of propylene oxide and 19 grams of ethylene oxide. The contents were further mixed and stoppered and the bottle placed in a steam bath for 21 hours. The viscous product obtained was bottled for storage.

Example 4 (Control or Comparative Example) A thickened water solution containing 10 percent of the polyether of Example 1 in combination with 0.5 percent of ethanolamine and 1.0 percent of the ester of two moles of phosphorus pentoxide and one mole of the condensation product of one mole of oleyl alcohol and four moles of ethylene oxide were combined. The sample had a viscosity (SUS) at 38°C of 8.87 cSt. - 15 Example 5 (Control or Comparative Example) Utilizing the polyether of Example 3, a 5 percent aqueous solution was prepared. The viscosity was found to be 25.50 cSt at 38°C.

Example 6 Utilizing the polyether of Example 3, a 5 percent solution in water was prepared containing 0.5 percent by weight of ethanolamine. The pH of the solution was found to be 9 and the viscosity was 25.15 cSt at 38°C.

Example 7 Utilizing the polyether of Example 3, a 5 percent by weight aqueous solution was prepared containing 0.5 percent by weight ethanolamine and 1.0 percent by weight of the phosphate ester of Example 4. The pH was found to be „9 and the viscosity was 117.4 cSt at 38°C.

Example 8 Utilizing the polyether of Example 3, a 5 percent by weight aqueous solution was prepared containing 0.5 percent by weight of ethanolamine and 1.0 percent by weight of the phosphate ester of Example 4. The pH was 9 and the viscosity was approximately 610 cSt at 38°C.

In the following table, the test results of Examples 1 and 3-10 are tabulated. These results indicate the unexpected synergistic thickening effects of amine and phosphate ester additives compared with polyether thickeners of the invention both unmodified and modified with alpha-olefin oxides. -16-P ω υ υ co •Η co η Ο -μ υ (ΰ 03 «Η > m m (β ο τρ ο ΙΠ ΙΛ CM CM *3* CM Η η in co CM χ j r» σι σι ω οί β Ο Ή -μ rtf οι β 0) 0 Ό Ό -Η β κ ο ο υ Synergistic Thickening of Aqueous Solutions β Ο Μ Μ 0) 4J Λ Φ-— •u Μ Φ -P ; >,£► Η 0) dp ο α* β* β ο U Ο I I ο ο • II·· γΊ I I Η Η ιη ι ιη • ι Ο I ο ιη ο ο ο in in ιη ιη ι—I *-ί μ Η Μ-Ι Λ ο -μ φ φ η m β ° ω Φ Φ β η ° β Ό β Μ Φ β φ Ή Ή *β κ β Ο Φ 4J β Η Φ ο D<33 Ο W □ β Η Μ rtf Ο Λ Η Λ >ι W Φ ΟΗ £ 0 M-t m ο ο φ Η Φ ο Η S β Φ Η γ-ί «Η 0 Ο 0 Μ Μ Μ Ρ •Ρ 43 β β β Φ 0 0 0 r4 υ Ο 0 α ·—' κ Η Η «3· ιη 0) β •Η 43 44 Ο U4 ι-ί ο «μ 0 ο β H β φ φ »β 33 •Ρ 0 -μ to h Φ Φ & Η CM - 17 While thia Invention has been described with reference to certain specific embodiments, it will be recognized by those skilled in the art that many variations are possible.

Claims (16)

1. A polyether-based thickener for aqueous systems comprising 90 to 65 percent by weight, based on the total weight 5 of the thickener, of a polyether having a molecular waight of 1000 to 75,000 which is prepared by reacting (1) ethylene oxide or (2) ethylene oxide and at least one lower alkylene oxide having 3 to 4 carbon atoms, with at least one active hydrogen-containing 10 polyhydric alcohol initiator and at least one alphaolefin oxide or at least one glycidyl ether having a carbon chain length of 12 to 18 aliphatic carbon atoms and wherein said alphaolefin oxide or glycidyl ether is present in the 15 amount of 1 to 20 percent by weight based upon the total weight of said polyether, and a mixture of a water-soluble amine and an ethoxylated phosphate ester, or an ethoxylated

2. O phosphate ester alone, wherein said phosphate ester has the formula θ Q II H RO (EO) n — P —OX or RO- (EO) n ~ P — (EO) n -OR Ax OX or a mixture thereof, wherein EO is ethylene oxide; R is a linear or branched chain alkyl 25 group having 6 to 30 carbon atoms, or an aryl or alkylaryl group wherein said alkylaryl group has from 6 to 30 carbon atoms; X is the residue of ammonia or an amine, or is hydrogen or an alkali or alkaline earth metal or a mixture thereof; and n is a number from 1 to 50. - 19 2. A thickener according to claim 1, which is liquid at ambient temperature, wherein said polyether is prepared by copolymerizing a mixture of said reactants to produce a heteric copolymer and wherein said water-soluble amine and said phosphate ester are present in the proportion by weight of 20 to 50 percent of said amine and 80 to 50 percent by weight of said phosphate ester based upon the total weight of said amine and phosphate ester.

3. A thickener according to claim l f wherein said polyether is prepared by copolymerizing a mixture of ethylene oxide and at least one of said lower alkylene oxides to produce a heteric copolymer intermediate and subsequently reacting said intermediate with at least one of said alpha-olefin oxide.

4. A thickener according to claim 1, wherein said polyether is prepared by sequentially reacting ethylene oxide with at least one of said lower alkylene oxides to produce a block copolymer intermediate and subsequently reacting said intermediate with at least one of said alpha-olefin oxide.

5. A thickener according to any one of claims 1 to 4, wherein said lower alkylene oxide is 1,2propylene oxide, 1,2-butylene oxide, 1,3-butylene oxide, 1,4-butylene oxide, 2,3-butylene oxide or tetrahydrofuran and the proportion of ethylene oxide in said polyether is at least 10 percent by weight of the total weight of said thickener.

6. A thickener according to claim 5, therein the proportion of ethylene oxide to said lower alkylene oxides is from 70 to 99 percent by weight of ethylene oxide to 30 to 1 percent by weight of the said lower alkylene oxides and said active hydrogen containing compound is a polyhydric alcohol having from 2 to 10 carbon atoms and from 2 to 6 hydroxyl groups.

7. A thickener according to claim 6, wherein said polyhydric alcohol initiator is - 20 an alkane polyol, an alkene polyol, an alkylene polyol, an aromatic polyol or an oxyalkylene polyol.

8. A thickener according· to claim 7, wherein • said alkane polyol initiator is at least one of trimethyl5 olpropane, glycerol, 2,3,5,6-hexanetetrol, sorbitol, or pentaerythritol, the molar ratio of said initiator to said alpha-olefin oxide is from 1:5 to 1:15, and said phosphate ester is the ester of two moles of phosphorus pentoxide and one mole of the condensation product of one mole of oleyl 10 alcohol and 4 moles of ethylene oxide.

9. A process of thickening aqueous systems comprising the addition of.an effective amount of a thickener to said aqueous system, said thickener comprising 90 to 65 percent by weight, based on the total weight of the thickener, of a polyether having a molecular weight of 1000 to 75,000 which is prepared by reacting (1) ethylene oxide or (2) ethylene oxide and at least one lower alkylene oxide having 3 to 4 carbon atoms with at least one active hydrogen-containing polyhydric alcohol initiator compound and at least one alpha-olefin oxide having a carbon chain length of 12 to 18 carbon atoms and wherein said alphaolefin oxide is present in the amount of 1 to 20 percent by weight based upon the total weight of said polyether and a mixture of a water-soluble amine and an ethoxylated phosphate ester, or an ethoxylated phosphate ester alone, 30 wherein said phosphate ester has the formula - 21 0 I RO-(EO) - P - OX or RO - (E0)„—P—(EO) ·— OR n j n j n OX OX or a mixture thereof, wherein EO is ethylene oxide; R is a linear or branched chain alkyl group having 6 to 30 carbon atoms, or an aryl or alkylaryl group wherein said alkylaryl group has from 6 to 30 carbon atoms; X is the residue of ammonia or an amine, or is hydrogen or an alkali or alkaline earth metal or a mixture thereof; and n is a number from 1 to 50.

10. A composition comprising water and the polyether thickener according to any one of claims 1 to 8.

11. A composition according to claim 10, additionally containing ethylene glycol.

12. A composition according to claim 10 or 11, wherein said polyether is a liquid and is prepared by the heteric polymerization of a mixture of ethylene oxide and propylene oxide with trimethylolpropane as initiator to produce an intermediate heteric copolymer which is substantially capped with said alpha-olefin oxide to produce a polyether having a molecular weight of 1000 to 40,000 and wherein said amine is ethanolamine and said phosphate ester is the ester of two moles of phosphorus pentoxide and one mole of the condensation product of one mole of oleyl alcohol and four moles of ethylene oxide.

13. A polyether-based thickener according to Claim 1, substantially as hereinbefore described and exemplified.

14. A process according to Claim 9 of thickening aqueous systems, substantially as hereinbefore described and exemplified.

15. Aqueous systems whenever thickened by a process claimed in Claim 9 or 14. - 22

16. A composition according to Claim 10, substantially as hereinbefore described and exemplified.