BR122024016504A2 - COPOLYMER, DISPERSANT COMPOSITION, DISPERSION, WETABLE POLYMER COMPOSITION, SUSPENSION CONCENTRATE, WATER-DISPERSIBLE GRANULE OR A FILMING AND METHOD FOR MAKING A DISPERSANT - Google Patents

Abstract

Copolymers comprising recurring units of a phenyl glycidyl ether and alkylene oxides are disclosed. Some of the copolymers comprise a di- or polyfunctional nucleophilic initiator and recurring units of the phenyl glycidyl ether and an alkylene oxide. The di- or polyfunctional nucleophilic initiator is an alcohol, phenol, amine, thiol, thiophenol, sulfinic acid or deprotonated species thereof. Other copolymers comprise a monofunctional nucleophilic initiator selected from thiols, thiophenols, aralkylated phenols, sulfinic acids, secondary amines, C10-C20 terpene alcohols and deprotonated species thereof. Pigment dispersions comprising the copolymers are also disclosed. Copolymers meet the growing needs of industry with their ease of fabrication, diverse structures, and desirable performance attributes for dispersing a wide range of organic and inorganic pigments. Agricultural applications for copolymers are also disclosed.

Description

FIELD OF INVENTION

[0001] The invention relates to copolymers, dispersant compositions comprising the copolymers and pigment dispersions using the dispersant compositions.

FUNDAMENTALS OF THE INVENTION

[0002] Phenyl glycidyl ether ("PGE") is known as a monomer for ring-opening polymerizations, including reactions to make random or block copolymers of alkylene oxides and PGE (see, e.g., U.S. Pat. Nos. 6,825,273). Some reported copolymers are generated with a monofunctional, monounsaturated initiator, such as allyl alcohol (see, e.g., U.S. Pat. Nos. 7,388,068; 7,605,224; and 7,812,114). Linear block copolymers of PGE and ethylene oxide made with monofunctional alcohol initiators (e.g., 1-octanol or 3-phenyl-1-propanol) and their use in pigment dispersions are also known (see N. Suto et al., J. Jon. Oil Chem. Soc. 31 (1982) 598 and U.S. Patent No. 8,367,762).

[0003] Pigment dispersions come in many varieties. The medium may be aqueous, polar organic, or nonpolar organic, and the pigment may be of many types of organic or inorganic materials. It is difficult to predict which dispersant will provide a satisfactory dispersion for any given pigment among hundreds of possible pigments. This creates a great need for commensurate variety in the available pigment dispersants.

[0004] The hydrophobic nature of the phenyl glycidyl ether blocks and the relatively hydrophilic nature of the ethylene oxide blocks provide opportunities to produce polymeric dispersants that can work with a variety of organic and inorganic pigments, especially in aqueous media. The preferred copolymers could effectively disperse various types of pigments to yield aqueous dispersions with low viscosity, good optical properties, and desirable particle sizes in the 100 to 1000 nm range. The preferred copolymers would also have low or zero VOC character to aid in compliance with increasingly stringent regulations. Preferably, the copolymers could yield good dispersions at low usage levels and allow for improved productivity by dispersing more pigments per unit time.

SUMMARY OF THE INVENTION

[0005] In one aspect, the invention relates to copolymers comprising recurring units of a phenyl glycidyl ether, especially (unsubstituted) phenyl glycidyl ether ("PGE"). The copolymers comprise a di- or polyfunctional nucleophilic initiator, from 1 to 30 recurring units per active hydrogen equivalent of the initiator of a phenyl glycidyl ether and from 1 to 100 recurring units per active hydrogen equivalent of the initiator of one or more alkylene oxides (“AO”) selected from ethylene oxide, propylene oxide, butylene oxides and combinations thereof. The di- or polyfunctional nucleophilic initiator is selected from alcohols, phenols, amines, thiols, thiophenols, sulfinic acids and deprotonated species thereof. The copolymer comprises from 20 to 60% by weight of the recurring units of phenyl glycidyl ether based on the combined amounts of the phenyl glycidyl ether and recurring AO units. In addition, the copolymers have a number average molecular weight in the range of 1,900 to 56,000 g/mol.

[0006] In another aspect, the invention includes copolymers comprising recurring units of a phenyl glycidyl ether, one or more alkylene oxides, and a monofunctional nucleophilic initiator selected from thiols, thiophenols, aralkylated phenols, sulfinic acids, secondary amines, C10-C20 terpene alcohols, and deprotonated species thereof. Such copolymers also comprise from 1 to 30 recurring units per equivalent of active hydrogen of the initiator of a phenyl glycidyl ether and from 1 to 100 recurring units per equivalent of active hydrogen of the initiator of one or more alkylene oxides selected from ethylene oxide, propylene oxide, butylene oxides, and combinations thereof. The copolymers comprise from 20 to 60 wt % of recurring phenyl glycidyl ether units based on the combined amounts of the phenyl glycidyl ether and recurring AO units. In addition, the copolymers have a number average molecular weight in the range of 1,900 to 12,000 g/mol.

[0007] The invention includes dispersions comprising a carrier (preferably water), a solid (preferably a pigment), typically a pH adjusting agent and the copolymers described above.

[0008] The universe of available pigments and their numerous uses require commensurate and diverse dispersants with the ability to produce aqueous dispersions having desirably low viscosities and practical particle size distributions. By varying the identity and functionality of the initiator, the proportions and distribution of the phenyl glycidyl ether and alkylene oxide(s), and the nature of any protecting groups, a family of compositions useful as pigment dispersants are readily produced. The phenyl glycidyl ether copolymers described herein meet the growing needs of industry with their ease of fabrication, diverse structures, and desirable performance attributes, including low or zero VOC character, for dispersing a wide range of organic and inorganic pigments in organic media.

DETAILED DESCRIPTION OF THE INVENTION Architectures:

[0009] Copolymers useful as dispersants may have a variety of different general structures or "architectures". For example, they may be linear with one tail extending from the initiator, linear with two tails extending from the initiator, "T-shaped" (i.e., three tails extending from a central initiator), "star-shaped" (i.e., four or more tails extending from a central initiator), or "comb-shaped" (polyfunctional initiator backbone with the tails as "teeth" of the comb).

[0010] Generally, the structure will include a nucleophilic initiator, one or more phenyl glycidyl ether units (typically a block of 2 to 20 phenyl glycidyl ether units per active hydrogen of the initiator), one or more alkylene oxide units (ethylene oxide (“EO”), propylene oxide (“PO”), or butylene oxides (“BO”) in homopolymer or random or block copolymer configurations), and optionally a protecting group. As will be discussed later, copolymers can be built starting from the initiator or, in some cases in reverse order, starting from the protecting group or a polyoxyalkylene or an alkyl-protected polyoxyalkylene initiator.

[0011] In some aspects, the copolymers may have a bolaphilic or amphiphilic structure comprising alternating blocks of hydrophobic (e.g., PGE) and hydrophilic (e.g., EO) groups. For example, a polyethylene glycol initiator could be reacted at both ends with PGE to add hydrophobic blocks, optionally with a protecting group. Bolaphiles or amphiphiles could also be made using the strategies described for making linear, T-shaped, or star-shaped copolymers.

Nucleophilic initiators:

[0012] Copolymer dispersants are typically synthesized from a nucleophilic initiator. The nucleophilic initiator may be monofunctional, difunctional, or polyfunctional.

1. Monofunctional nucleophilic primers

[0013] When the desired copolymer has a single tail, a monofunctional nucleophilic initiator is used. Suitable monofunctional nucleophilic initiators include thiols, thiophenols, aralkylated phenols, aryl-substituted phenols, sulfinic acids, secondary amines, C10-C20 terpene alcohols, and deprotonated versions thereof.

[0014] Suitable monofunctional thiols, thiophenols, aralkylated phenols, aryl-substituted phenols, and sulfinic acids include, for example, hexanethiol, octanethiol, 1-dodecanethiol, benzyl mercaptan, furfuryl mercaptan, 2-benzothiazolylthiol, thiophenol, 4-chlorothiophenols, styrenated phenols, 4-(triphenylmethyl)phenol, 4-phenylphenol, phenylsulfinic acid, and the like, and mixtures thereof. After serving as an initiator, the sulfur atoms in many of these initiators can be oxidized to yield sulfoxides or sulfones, as illustrated below. By controlling the stoichiometry of the oxidant, some or all of the sulfur atoms can be oxidized (see Scheme 6). When a sulfinic acid is used as an initiator, a sulfone is produced directly.

[0015] Secondary amines also serve as initiators for single-tailed copolymers. Suitable secondary amines include, for example, diethylamine, di-n-propylamine, di-n-butylamine, diisopropylamine, di-n-octylamine, N-methylaniline, morpholine, piperidine, diphenylamine, dibenzylamine, imidazoles, 1,1,3,3-tetramethylguanidine, and the like. After serving as an initiator, any resulting tertiary nitrogen atoms in these initiators can be quaternized or converted to N-oxides (see Scheme 6).

[0016] Suitable C10-C20 terpene alcohols include, for example, farnesol, terpineol, linalool, geraniol, nerolidol, geranylgeraniol and the like and mixtures thereof.

2. Di- or polyfunctional nucleophilic initiators

[0017] When the desired copolymer has two or more tails, a di- or polyfunctional nucleophilic initiator is used. The average functionality of these initiators is determined by the sum of the total active hydrogens bonded to an oxygen, nitrogen or sulfur atom. Preferred di- or polyfunctional nucleophilic initiators will have average functionalities in the range of 2 to 8, 2 to 6 or 2 to 4.

[0018] Suitable di- or polyfunctional nucleophilic initiators include alcohols, phenols, amines, thiols, thiophenols, sulfinic acids and deprotonated species thereof. Thus, suitable di- or polyfunctional nucleophilic initiators include polyfunctional alcohols (diols, triols, tetrols, sugars and the like), polyphenols, primary amines, di- or polyfunctional secondary amines, sulfur-containing di- or polyfunctional initiators (thiols, dithiols, thiophenols, sulfinic acids), mixed nucleophiles and the like.

[0019] Suitable polyfunctional alcohols include, for example, 1,3-propanediol, 2-methyl-1,3-propanediol, 1,4-butanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, 1,8-octanediol, 1,12-dodecanediol, ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycols having average molecular weights of 400 to 4,000 g/mol, glycerol, trimethylolpropane, trimethylolethane, pentaerythritol, di(pentaerythritol), di(trimethylolpropane), bis-tris methane, 1,4-cyclohexanedimethanol, 1,4-dihydroxy-2-butyne, 2,4,7,9- tetramethyl-5-decyn-4,7-diol, isosorbide, castor oil, xylitol, sorbitol, glucose, 1,2-O-isopropylidene-a, D-glucofuranose, N-methyldiethanolamine, triethanolamine, polyglycerols, polyvinyl alcohols and the like, and mixtures thereof. After serving as an initiator, any resulting tertiary nitrogen atoms in these initiators may be quaternized or converted to N-oxides.

[0020] Suitable polyphenols include, for example, bisphenols (e.g., bisphenol A, bisphenol F, bisphenol S, bisphenol acetophenone), biphenols (2,2'-biphenol, 4,4'-biphenol), resorcinol, catechol, 1,6-dihydroxynaphthalene, phloroglucinol, pyrogallol, ellagic acid, tannins, lignins, natural polyphenols, poly[phenol-co-formaldehyde], poly[cresol-co-formaldehyde] and the like and mixtures thereof.

[0021] Suitable amines include primary amines such as, for example, n-butylamine, n-octylamine, cocamine, oleylamine, cyclohexylamine, benzhydrylamine, taurine, anilines (e.g., 4-chloroaniline, 4-aminophenol, 3-methoxyaniline, 4,4'-diaminodiphenylmethane, sulfanilamide), benzylamines, benzenesulfonamide, ethylenediamine, diethylenetriamine, melamine, N,N-dimethylethylenediamine, 3,3'-diaminobenzidine, polyetheramines, polyethylenimines, and the like.

[0022] Suitable amines also include di- or polyfunctional secondary amines such as, for example, piperazine, N,N'-dimethylethylenediamine, N,N'-dimethyl-1,6-hexanediamine, N,N'-dimethyl-1,8-octanediamine, 1,3,5-triazinane, 4,4'-trimethylenedipiperidine, and the like. After serving as an initiator, nitrogen atoms in these initiators may be quaternized or converted to N-oxides. Primary amines provide two-tailed initiators. Some of the initiators (e.g., ethylenediamine, diethylenetriamine, melamine, polyethylenimines, polyetheramines) provide a starting point for multiple tails.

[0023] Suitable initiators containing di- or polyfunctional sulfur include, for example, 1,4-butanedithiol, 1,6-hexanedithiol, 2,2'-(ethylenedioxy)diethanethiol, trithiocyanuric acid and the like, and mixtures thereof. After serving as an initiator, the sulfur atoms in many of these initiators can be oxidized to yield sulfoxides or sulfones.

[0024] Suitable di- or polyfunctional mixed nucleophiles include, for example, ethanolamine, 2-mercaptoethanol, 2-aminoethanethiol, diethanolamine, 4-aminophenol, 4-aminothiophenol, glucosamine, 2-amino-1,3-propanediol, 1,3-diamino-2-propanol, 3-mercapto-1,2-propanediol, bis-trispropane, 4-hydroxy-1,2,2,6,6-pentamethylpiperidine and the like, and mixtures thereof. After serving as an initiator, the nitrogen and/or sulfur atoms may be oxidized or quaternized as described above.

[0025] Suitable nucleophilic initiators include partially or fully deprotonated species corresponding to any of the above protonated materials. As those skilled in the art will appreciate, many convenient syntheses of the copolymers will begin by the reaction of a monofunctional nucleophilic initiator (thiol, thiophenol, secondary amine or C10-C20 terpene alcohol) or a di- or polyfunctional nucleophilic initiator (alcohol, phenol, amine, thiol or thiophenol) with a deprotonating agent. Suitable deprotonating agents are well known and include, for example, metal hydrides (LiH, NaH, KH, CaH2), metal alkoxides (sodium methoxide, sodium ethoxide, potassium ethoxide, potassium tert-butoxide), methyl hydroxides (NaOH, KOH), metal carbonates (NaHCO3, Na2CO3, K2CO3, CS2CO3), amines (trimethylamine, N,N-diisopropylethylamine, pyridine) and the like.

Phenyl glycidyl ethers

[0026] The copolymer dispersants comprise recurring units of a phenyl glycidyl ether, especially unsubstituted phenyl glycidyl ether ("PGE"). In some aspects, the dispersants comprise from 1 to 30, from 2 to 20, from 2 to 15, or from 2 to 5 recurring phenyl glycidyl ether units per active hydrogen equivalent of the initiator. As used herein, "active hydrogen equivalent" refers herein to a group having an active hydrogen atom (alcohol, thiol, amine) or its deprotonated counterpart. In some aspects, the recurring phenyl glycidyl ether units occur in a single block. In other aspects, the recurring phenyl glycidyl ether units are interspersed with recurring units of alkylene oxides, functionalized glycidyl ethers, or other monomers, as described below. In a preferred aspect, a block of recurring phenyl glycidyl ether units is reacted with the nucleophilic initiator as a first step of the reaction. In some aspects, an alkyl, alkoxy, or halo-substituted phenyl glycidyl ether (e.g., 2-methylphenyl glycidyl ether, 4-methoxyphenyl glycidyl ether, or 2-chlorophenyl glycidyl ether) is used instead of or in addition to PGE. In other aspects, styrene oxide is used to replace some or all of the recurring phenyl glycidyl ether units.

Alkylene oxides

[0027] The copolymer dispersants comprise recurring units of one or more alkylene oxides. In some aspects, the dispersants comprise from 1 to 100, from 5 to 80, from 10 to 60, or from 20 to 40 recurring units per equivalent of active hydrogen of the initiator of one or more alkylene oxides selected from the group consisting of ethylene oxide, propylene oxide, butylene oxides, and combinations thereof. The recurring alkylene oxide units may be arranged in a random, block, or gradient fashion, for example, as blocks of a single alkylene oxide, blocks of two or more alkylene oxides (e.g., a block of EO units and a block of PO units), or as a random copolymer. In preferred aspects, the alkylene oxide is ethylene oxide, propylene oxide, or combinations thereof. In more preferred aspects, the alkylene oxide consists essentially of ethylene oxide, which gives the copolymer a hydrophilic character.

Other monomers

[0028] Copolymer dispersants may incorporate recurring units of other monomers capable of copolymerizing with phenyl glycidyl ether or the above-mentioned alkylene oxides. The other monomers include, for example, other glycidyl ethers (e.g., butyl glycidyl ether, isopropyl glycidyl ether, t-butyl glycidyl ether, 2-ethylhexyl glycidyl ether, allyl glycidyl ether, benzyl glycidyl ether, guaiacol glycidyl ether, 1-ethoxyethyl glycidyl ether, 2-ethoxyethyl glycidyl ether, 2-methylphenyl glycidyl ether, 2-biphenyl glycidyl ether, tristyrylphenol glycidyl ether, 3-glycidyl(oxypropyl)trimethoxysilane, 3-glycidyl(oxypropyl)triethoxysilane, propargyl glycidyl ether), other epoxides (e.g., styrene oxide, cyclohexene oxide, 1,2-epoxyhexane, 1,2-Epoxyoctane, 1,2-epoxydecane, 1,2-epoxydodecane, 1,2-epoxyteradecane, 1,2-epoxhexadecane, 1,2-epoxyoctadecane, 1,2-epoxy-7-octene, 3,4-epoxytetrahydrofuran, (2,3-epoxypropyl)trimethylammonium chloride), thiiranes (phenoxymethyl thiirane, 2-phenylthiirane), caprolactone, tetrahydrofuran and the like. Thiiranes can be produced from the corresponding epoxides and thiourea as described, for example, in Yu et al., Synthesis (2009) 2205.

[0029] In some aspects, the reaction of the nucleophilic initiator with an epoxy functional monomer (epoxide, glycidyl ether) is used to produce a more complex "initiator" that can be further reacted with recurring phenyl glycidyl ether units and alkylene oxides.

[0030] For example, the reaction of triethanolamine with three equivalents of 3,4-epoxytetrahydrofuran (or 1,2-epoxyhexadecane, for example) provides a composition having three free hydroxyl groups. This "starter" can then be reacted with phenyl glycidyl ether to produce a hydrophobe, which is further reacted with ethylene oxide (or EO/PO combination) to give a suitable dispersant. Examples of hydrophobes of this type are shown below:

[0031] Similarly, reaction of trimethylolpropane with three equivalents of allyl glycidyl ether results in a complex initiator which can be further reacted with PGE to give a hydrophobe and then ethoxylated to give the dispersant:

[0032] In yet another example, the complex initiator is made by reacting triethanolamine with three equivalents of 2-ethylhexyl glycidol to yield the hydroxy functional complex initiator. Further reaction with PGE and then EO provides the desired dispersant:

Functionalized glycidyl ethers

[0033] Copolymer dispersants may incorporate one or more glycidyl ether units having an embedded functional "loop." Suitable functionalized glycidyl ethers have a glycidyl ether group, a linking group, and a functional loop. The linking group is any combination of atoms or bonds capable of linking the glycidyl ether group to the functional loop. Suitable functional loops will have functional groups capable of further manipulation. For example, if the functionalized glycidyl ether incorporates a benzaldehyde "loop," the free aldehyde group may be reacted with an amine to give an imine, an amino acid to give an imine acid, or an anhydride to give a cinnamic acid derivative via the Perkin reaction. In another example, if the functionalized glycidyl ether incorporates a thioether "loop," oxidation may provide a sulfoxide or a sulfone.

[0034] Commercially available 1-ethoxyethyl glycidyl ether (i.e., 2-[(1-ethoxyethoxy)-methyl]oxirane) can be used to introduce an acid-sensitive hemiacetal (RO-CH(CH3)OEt) as the functional handle. Subsequent treatment with an acid releases the alcohol (ROH), which can be converted to a phosphate, sulfate, acetate, or other useful functionalities.

[0035] In another exemplary synthetic approach, the nucleophilic initiator is reacted first with a portion of the phenyl glycidyl ether to be used, then with a desired proportion of functionalized glycidyl ether, and then with the remaining amount of the phenyl glycidyl ether to incorporate the functionality into the recurring phenyl glycidyl ether unit block. The introduction of heteroatoms or charged functionalities (e.g., amine oxides) may be useful for dispersing inorganic pigments.

Hydrophobic synthesis

[0036] In a preferred aspect, the nucleophilic initiator is reacted with a phenyl glycidyl ether in the presence of a catalyst, preferably a basic catalyst. In some aspects from 1 to 30, from 2 to 20, and preferably from 2 to 15 or from 2 to 5 equivalents of phenyl glycidyl ether are used per equivalent of active hydrogen of the initiator. In a preferred approach, about 5 equivalents of phenyl glycidyl ether per active hydrogen in the initiator are used, as this provides a desirable level of hydrophobicity. It may be desirable to perform the reaction, at least initially, in the presence of a solvent. Ether solvents, such as methyl t-butyl ether (MTBE) work well with alkoxide catalysts. In a suitable approach, a reaction vessel is charged with the required amount of nucleophilic initiator and solvent and a suitable catalyst (e.g., potassium methoxide) is added. An initial charge of phenyl glycidyl ether is added and the solvent is removed. As the temperature increases, the ring-opening reaction proceeds and the mixture is exothermic. Addition of phenyl glycidyl ether continuously or in increments allows control over exothermic reactions. The progress of the reaction can be monitored by 1H NMR or other suitable techniques. The resulting hydrophobic alkoxide is typically used "as is" for subsequent reaction steps.

[0037] The hydrophobic portion of the copolymer will have preferred average molecular weights as measured by gel permeation chromatography (GPC) that are somewhat dependent on functionality as shown in the following table:

[0038] Scheme 1 illustrates hydrophobe syntheses using PGE, potassium methoxide catalyst, MTBE solvent, and a variety of nucleophilic initiators to produce single-tailed, two-tailed, three-tailed, and four-tailed hydrophobes. Scheme 2 illustrates syntheses in which alternatives to PGE are included.

Alkoxylation

[0039] Alkoxylation typically follows the reaction of the nucleophilic initiator, the catalyst, and the phenyl glycidyl ether to produce the hydrophobe. Hydroxyl groups of the hydrophobe react in the presence of the catalyst with one or more equivalents of an alkylene oxide to yield the alkoxylated product. In some aspects, sufficient alkylene oxide is added to introduce from 1 to 100, from 2 to 80, from 5 to 60, or from 10 to 40 recurring alkylene oxide units per equivalent of active hydrogen of the nucleophilic initiator. In some aspects, the alkylene oxide is selected from the group consisting of ethylene oxide, propylene oxide, butylene oxides, and combinations thereof. The recurring alkylene oxide units may be arranged in a random, block or gradient fashion, for example as blocks of a single alkylene oxide, blocks of two or more alkylene oxides (e.g. a block of EO units and a block of PO units), or as a random copolymer. In preferred aspects, the alkylene oxide is ethylene oxide, propylene oxide or combinations thereof. In more preferred aspects, the alkylene oxide consists essentially of ethylene oxide.

[0040] Although basic catalysts are typically more convenient, alternative catalysts may be used in some aspects. For example, Lewis acids, such as boron trifluoride, may be used to polymerize PGE and alkylene oxides. Double metal cyanide catalysts may also be used (see, e.g., U.S. Patent Nos. 5,470,813; 5,482,908; 6,852,664; 7,169,956, 9,221,947, 9,605,111; and U.S. Publication Nos. 2017/0088667 and 2017/0081469).

[0041] The alkoxylation reaction is conveniently carried out by gradual addition of the alkylene oxide as mixtures or in steps to produce the desired architecture. The reaction mixture will normally be heated until most or all of the alkylene oxide has reacted to give the desired copolymer. Following alkoxylation, the copolymer can be neutralized to yield a hydroxy functional dispersant. In some cases, it may be desirable to convert the hydroxyl groups to other functional groups such as sulfates, phosphates, amines or the like. In other cases, it may be desirable to protect the hydroxyl groups to yield ethers, esters, carbonates, carbamates or the like using the protecting groups discussed above. Some representative alkoxylation processes are shown below in Scheme 3.

[0042] Alkoxylates will possess preferred number average molecular weights as measured by gel permeation chromatography (GPC) that are somewhat dependent on functionality as shown in the following table:

More dispersants

[0043] In another aspect, the dispersant is produced from a different type of complex initiator. In this case, a di- or polyfunctional glycidyl ether or a di- or polyfunctional epoxide is reacted with an alcohol, secondary amine, or thiol to yield a hydroxy functional intermediate. This intermediate is then reacted with a phenyl glycidyl ether to yield a hydrophobe. The hydrophobe is then alkoxylated as described above to yield the dispersant. An exemplary dispersant produced in this manner from resorcinol diglycidyl ether, 1-dodecanethiol, PGE, and ethylene oxide is shown below:

Reverse synthesis

[0044] An alternative way to produce the copolymers useful as dispersants is to use a reverse or inverse synthesis. An advantage of this approach would be to avoid an alkoxylation process when a suitable ether-protected polyalkylene glycol initiator is a commercial article or otherwise readily available. For example, methoxy-capped polyethylene glycol can be converted to the alkoxide with a base catalyst and then reacted with a desired number of equivalents of phenyl glycidyl ether, followed by any desired "nucleophilic initiator" to complete the synthesis.

[0045] In a "reverse synthesis" strategy, the hydrophilic moiety is more centrally located. For example, ether-protected polyalkylene glycol (e.g., mPEG) can be reacted with an equivalent amount of di- or polyfunctional glycidyl ether (e.g., resorcinol diglycidyl ether or 1,4-butanediol diglycidyl ether) to yield a hydroxy functional intermediate. This intermediate is then reacted with a phenyl glycidyl ether and any other epoxides and/or protecting groups to extend the hydrophobic moiety. The following dispersants illustrate products that could be made by this strategy:

[0046] In another "reverse synthesis" strategy, a di- or polyfunctional carboxylic acid, ester, acid anhydride or chloride, or a di- or polyisocyanate, or a di- or polyfunctional arylsulfonyl halide may be used to quench free hydroxyl groups in a finishing step after chain extension from ether-protected polyalkylene glycol and a phenyl glycidyl ether. The following dispersants illustrate products made by this strategy:

Functionalized glycidyl ethers

[0047] Commercially available 1-ethoxyethyl glycidyl ether (i.e., 2-[(1-ethoxyethoxy)-methyl]oxirane) can be used to introduce an acid-sensitive hemiacetal (RO-CH(CH3)OEt) as the functional handle. Subsequent treatment with an acid releases the alcohol (ROH), which can be converted to a phosphate, sulfate, acetate, or other useful functionalities (see Scheme 4).

Protection groups and reactions

[0048] In some aspects, the copolymer dispersants may include a protecting group. The protecting group may be used to cover some or all of the available hydroxyl groups of the alkoxylates. Suitable protecting groups for hydroxy functional polymers are well known. Examples include ethers, esters, carbonates, carbamates, carbamimidic esters, borates, sulfates, phosphates, phosphatidylcholines, ether acids, ester alcohols, ester acids, ether diacids, ether amines, ether ammoniums, ether amides, ether sulfonates, ether betaines, ether sulfobetaines, ether phosphonates, phospholanes, phospholane oxides, and the like, and combinations thereof. For structures of many of these protecting groups, see Scheme 5, below. Scheme 6 illustrates acetylation, phosphation, sulfation, and alkylamination as possible protection approaches.

[0049] Succinic anhydride, for example, can be used to protect some or all of the available terminal hydroxyl groups of a dispersant. Deprotonation of the resulting carboxylic acid groups can significantly alter the hydrophilicity of the dispersant. Reaction of triethanolamine with PGE, followed by ethoxylation and protection with sufficient succinic anhydride to react with one-third of the hydroxyl groups, results in this dispersant:

Additional reaction to sulfur or nitrogen; branched tails:

[0050] As noted above, the nitrogen atoms from the nucleophilic initiator can be alkylated or oxidized to yield quaternized compositions or amine oxides, respectively. Similarly, the sulfur atoms from the nucleophilic initiator can be oxidized to sulfoxide functionality, sulfone functionality, or both. Scheme 7 provides some illustrations.

[0051] In some aspects, it may be desirable to introduce additional branches into the hydrophobe prior to alkoxylation. This may be achieved by reacting the prepared hydrophobe with 1-ethoxyethyl glycidyl ether followed by acid-mediated hydrolysis of the residual hemiacetal functionality to effectively double the number of free hydroxyl groups available for alkoxylation. For example, reaction of trimethylolpropane with about five equivalents of PGE to afford the hydrophobe, followed by reaction with one equivalent of 1-ethoxyethyl glycidyl ether, acid-mediated hydrolysis to liberate the additional hydroxyl functionalities from the hemiacetals, and then ethoxylation provides a dispersant having the structure shown immediately below.

[0052] Scheme 8 illustrates the syntheses of hydrophobes attached to the branched EO tails using both a forward and a forward-backward synthetic strategy.

Sulfonation/sulfation of aromatic rings

[0053] In some aspects, it may be desirable to use conventional sulfonating agents, e.g., sulfur trioxide, to sulfonate a portion of the aromatic rings present in the dispersant. In this manner, aromatic rings of recurring units of phenyl glycidyl ether, 2-methylphenyl glycidyl ether, styrene oxide, or other aromatic rings may be sulfonated to introduce sulfonate groups into the dispersant. In one example, triethanolamine-PGE(18)-EO(105) is reacted with sulfur trioxide under conditions effective to sulfonate at least a portion of the aromatic rings. Under typical sulfonation conditions, the free hydroxyl groups will also be sulfated, and in some cases, a mixed sulfate/sulfonate will be the desired end product. In this case, the reaction product is simply neutralized with a suitable base. If only a sulfonate is desired, any sulfates generated can be hydrolyzed, for example by dilute acid treatment, to regenerate free hydroxyl groups.

Pigments:

[0054] Pigments suitable for use in pigment dispersion are well known and readily available. Many of the pigments are organic compounds, although inorganic pigments are also common. Examples appear in U.S. Pat. No. 4,548,724, the teachings of which are incorporated herein by reference. Suitable organic pigments include, for example, monoazoles, diazos, anthraquinones, anthrapyrimidines, quinacridones, quinophthalones, dioxazines, flavanthrones, indanthrones, isoindolines, isoindolinones, metal complexes, perinones, perylenes, phthalocyanines, pyranthrones, thioindigos, triphenylmethanes, anilines, benzimidazolones, diarylides, diketopyrrolopyrroles, naphthols, and aldazines. Suitable inorganic pigments include, for example, white pigments, black pigments, chromatic pigments and luster pigments.

Pigment dispersions:

[0055] The copolymers are useful in the preparation of pigment dispersions, especially water-based pigment dispersions. Many of the copolymers of the invention are relatively water-soluble and provide stable dispersant solutions or emulsions. The pH of the dispersant solution or emulsion is typically adjusted with acid (e.g., hydrogen chloride) or base (e.g., sodium hydroxide) to be in the range of 3 to 12 or, in some aspects, in the range of 7 to 11 or 8 to 10 or 8.5 to 9.5. The pigments are combined with a carrier (preferably water), the copolymer, and any desired pH-adjusting agent, biocide, defoamer, rheology modifier, stabilizer, or other components to result in a mixture having the desired ratio of copolymer to pigment. Typically, the solids content of the pigment dispersion will be in the range of 5 to 95 wt.%, 15 to 90 wt.% or 25 to 85 wt.%. The mixtures are preferably ground, for example in a paint mixer with metal, ceramic or glass beads, to produce pigment dispersions that can be evaluated for the relevant physical properties.

[0056] A desirable aqueous pigment dispersion will have a low viscosity and an intermediate particle size. For example, the dispersion desirably has a viscosity of less than 5,000 cP at 25 °C and a shear rate of 10 s-1, preferably less than 3,000 cP at 25 °C and a shear rate of 10 s-1, more preferably less than 1,000 cP at 25 °C and a shear rate of 10 s-1. This shear rate corresponds to the amount of shear typically experienced by the dispersion during flow. The particle size of the aqueous dispersion, as measured by dynamic light scattering (or other suitable techniques) should be in the range of 100 nm to 1000 nm, preferably from 100 nm to 500 nm or from 100 nm to 300 nm.

[0057] Desirable pigment dispersions make efficient use of dispersant, which is typically a relatively expensive component of the dispersion. In other words, the less dispersant required for a given amount of pigment, the better. Usage level requirements for the present copolymers can vary, but typically in the range of 0.5 to 80 wt. %, 2 to 60 wt. %, or 3 to 50 wt. % copolymer dispersant based on the total amount of pigment dispersion.

[0058] Productivity is also important. The ability to produce a good dispersion in a short time translates into a reduced overall cost. We have found that the copolymers of the invention can result in stable, non-viscous dispersions having desirable particle sizes quickly with many pigments.

Abbreviated names

[0059] It is convenient to name copolymers by indicating the initiator used followed by PGE(x)AO(y) to indicate the number of moles of phenyl glycidyl ether and alkylene oxide used to make the copolymer. When a protecting group is used, a designation may be added after the alkylene oxide portion. Thus, a reaction product of morpholine with 5 moles of phenyl glycidyl ether and then 20 moles of ethylene oxide is conveniently abbreviated as: "morpholine-PGE(5)-EO(20)." When the nucleophilic initiator has more than one active hydrogen, the average number of PGE or EO units per arm can be approximated by dividing the total number of moles of PGE or EO indicated by the functionality of the initiator. Thus, “pentaerythritol-PGE(20)-EO(120)”, a primer with functionality = 4, nominally has an average of 5 units of PGE and 30 units of EO per arm, although, as the skilled artisan will understand, these values are approximations. The conventions are used in the examples below.

[0060] Certain copolymers of the invention may provide advantages when combined with particular pigments. We have found, for example, that the pigment monoazo yellow provides excellent aqueous dispersion when used at pH 8 to 10 in combination with the dispersants or dispersant blends listed in Tables 4, 4A, 4B and 5. Similarly, the pigment quinacridone violet provides excellent aqueous dispersion when used at pH 8 to 10 in combination with the dispersants or dispersant blends listed in Tables 6 and 6A. Phthalocyanine blue provides excellent aqueous dispersion when used at pH 8 to 10 when used in combination with the dispersants or dispersant blends listed in Tables 7, 8, 9 and 10.

Stabilization of latex emulsion

[0061] In one aspect, the invention includes a method comprising stabilizing flow properties of an emulsion latex polymer. The method protects against temperature-induced changes in properties occurring in the range of -20°C to 50°C. The method comprises combining the emulsion latex polymer with an effective amount of a dispersant composition produced by combining the copolymers described herein with water.

Alkyd compositions

[0062] In another aspect, the invention relates to a method for improving the hydrophobic character of an alkyd coating. This method comprises combining an alkyd resin with an effective amount of a dispersant composition comprising the copolymers described herein and a non-aqueous carrier, such as an organic solvent. In a preferred aspect, the alkyd resin comprises a reaction product of glycerol, soybean oil and isophthalic acid.

Agricultural applications

[0063] The copolymers of the invention are useful in agricultural formulations as emulsifiers, as dispersants for suspension concentrates, as dispersants for film coatings, as wetting agents, as spreaders, as adjuvants to promote absorption of actives onto leaf surfaces, and as dispersant components of water-dispersible granules. We have found, for example, that the copolymers perform as well as or better than controls as dispersants for wettable powders from atrazine, chlorothalonil, or imidacloprid (see Table 15 below). Good suspension concentrates comprising the copolymers of the invention can also be made (see, for example, Table 16 below). Suitable carriers for agricultural applications, particularly emulsions or suspension concentrates, include organic solvents, water, and combinations of water and water-miscible organic solvents.

Other applications

[0064] Polymers can be used to disperse solids (e.g., organic and/or inorganic pigments, fillers, or latexes) in coatings, as discussed above and in more detail below, relating to organic and inorganic pigments, especially organic pigments. However, polymers can also be used in agricultural applications (as discussed above) and as dispersants for other particulate materials, such as cement, minerals, asphaltene, or soil particles. Polymers may also find utility as rheology modifiers, foamers, defoamers, or auxiliary components of laundry detergents or personal care products, including cleaning products and cosmetics. Polymers may also be useful as coating additives, where they can improve film quality as compatibilizers, adhesion promoters, or leveling agents.

[0065] The following examples illustrate the invention; one skilled in the art will recognize many variations that are within the spirit of the invention and the scope of the claims.

Synthesis of Polymeric Dispersants

[0066] The procedures below can be used to produce the wide variety of copolymers of the invention listed in Tables 1 and 1A. Additional dispersants can be made in a similar manner by adding ethylene oxide, propylene oxide, or combinations thereof, and optionally a protecting group to the hydrophobes listed in Table 1B.

1. Synthesis of Hydrophobes (general procedure):

[0067] A 4-necked round bottom flask is equipped with a heating mantle, a temperature controller, a propeller stirrer, a thermocouple, a nitrogen inlet with a sparge tube, and a distillation adapter. An addition funnel, a water-cooled condenser, a gas outlet bubbler, and an Erlenmeyer flask are attached to the adapter. Under a nitrogen flow, the flask is charged with a nucleophilic initiator and methyl tert-butyl ether (MTBE). The mass of MTBE used is about 2-3 times that of the nucleophilic initiator. Solid potassium methoxide is added, and the mixture is heated to 55-65 °C. Rapid distillation of MTBE is started, and the first of five additions of phenyl glycidyl ether (PGE) begins from the addition funnel. For each addition, one equivalent of PGE is added for each mole of alcohol, disubstituted amine, or thiol initiator, and two equivalents of PGE are added for each mole of monosubstituted amine initiator. When the first addition is complete and most of the MTBE has distilled off, the reaction temperature slowly increases until an initial exotherm is observed. Depending on the identity of the nucleophilic initiator, the exotherm begins anywhere in the range of 70 °C to 140 °C. During the first and subsequent exotherms, the reaction temperature is controlled by adjusting the stirring rate or the temperature set point or by removing the heating mantle. When the first exotherm subsides, a second addition of PGE begins. From this point on, the reaction temperature is maintained in the range of 100 °C to 120 °C. The remaining three additions of PGE proceed as before. After all of the PGE has been added, the reaction temperature is maintained at 105 °C, and the progress of the reaction is measured by monitoring the PGE consumption by 1H NMR. When the reaction is complete, the product is used in the next step without further manipulation. The isolated material typically contains 0.35 to 0.55 wt% potassium. The product is a mixture of compounds with an average of five PGE units per nucleophilic site on the initiator.

2. Alkoxylation by hydrophobes (general procedure):

[0068] A 600 mL Parr reactor, equipped with a mechanical stirrer, a nitrogen sparger, a thermocouple, and a sample port, is charged with the potassium-containing hydrophobe prepared as described above. The reactor is sealed and the contents are slowly heated to 120 °C. When the target temperature is reached, one or more alkylene oxides are added to initiate alkoxylation. For monoblock tails composed of a single alkylene oxide monomer or a random mixture of two or more alkylene oxide monomers, the alkylene oxide monomer(s) is added batchwise until the target number of moles of monomer has reacted. For tails composed of more than one alkylene oxide block, the above procedure is repeated for each additional segment. When the alkoxylation is considered complete, the product is removed from the reactor at 80-90 °C. Additional Synthetic Examples 1. Resorcinol dialkyl ether-1-dodecanethiol(2)-PGE(10)

[0069] A round bottom flask equipped with a heating mantle, temperature controller, propeller stirrer, thermocouple, and nitrogen inlet is charged with 1-dodecanethiol (72.9 g, 360 mmol) and solid potassium methoxide (3.10 g, 44.2 mmol). The resulting mixture is heated to 105 °C, whereupon the portionwise addition of warm (54 °C) resorcinol diglycidyl ether (40.0 g, 180 mmol) is begun. The reagent is introduced by intermittently removing the gas outlet and adding the warm liquid by pipette. During the addition, the reaction temperature is maintained at or below 133 °C by controlling the rate of reagent addition and the rate of stirring. After 10 minutes, the addition is complete, and the reaction mixture is stirred and cooled to 100 °C. Complete consumption of resorcinol diglycidyl ether is observed by 1H NMR after stirring for 1 h at 100 °C.

[0070] An addition funnel charged with phenyl glycidyl ether (270.4 g, 1801 mmol) is introduced and the glycidyl ether is added over 34 min while maintaining the reaction temperature at or below 123 °C by controlling the rate of reagent addition and the rate of stirring. After the addition is complete, the reaction mixture is stirred at 110 °C. The progress of the reaction is monitored by measuring the consumption of the glycidyl ether by 1H NMR spectroscopy. After stirring for 4 h at 110 °C, analysis confirms that the reaction is complete. The hot reaction mixture is poured into a flask and allowed to cool to room temperature. The product, resorcinol-1-dodecanethiol(2)-PGE(10) diglycidyl ether (374.6 g, 98%) contains 0.45 wt % potassium.

[0071] A round bottom flask is equipped with a heating mantle, a temperature controller, a propeller stirrer, a thermocouple, a nitrogen inlet/sparge tube, and a distillation adapter. Attached to the adapter is an addition funnel, a water-cooled condenser, and an Erlenmeyer flask. The flask is charged under nitrogen with trimethylolpropane (154.6 g, 1.15 mol) and solid potassium methoxide (26.4 g, 0.377 mol). The resulting solid mixture is heated to 110 °C with stirring. After 15 minutes at 110 °C, a pale yellow solution is obtained. Phenyl glycidyl ether (2597 g, 17.29 mol) is then added via the addition funnel over 90 minutes. During the addition, the reaction temperature is kept at or below 140 °C by controlling the rate of reagent addition and the rate of stirring. After the addition is complete, the reaction mixture is stirred at 110 °C. After 4 h, 1H NMR shows complete consumption of the phenyl glycidyl ether. Stirring is discontinued, the reaction mixture is allowed to cool to room temperature, and the product is stored in the reaction flask under nitrogen overnight.

[0072] The solid reaction mixture is slowly heated to 100 °C. Once the mixture begins to melt, the propeller stirrer is activated. Once the mixture has liquefied, 1-ethoxyethyl glycidyl ether (505.8 g, 3.46 mol) is added via addition funnel over 0.5 h. When the addition is complete, the reaction mixture is stirred at 110 °C. After 16 h, 1H NMR shows complete consumption of the 1-ethoxyethyl glycidyl ether.

[0073] The hot reaction mixture is quantitatively transferred to a large round bottom flask using two washes of tetrahydrofuran (300 g) to complete the transfer. Ethanol (2.2 kg) and 5 more tetrahydrofuran (400 g) are added. A propeller stirrer and thermocouple are attached to the flask and the mixture is stirred at 47 °C. Aqueous hydrochloric acid (37%, 170 g, 1.72 mol) is added and the resulting mixture is stirred and allowed to cool slowly over 4.5 h to room temperature. During cooling, the mixture periodically becomes too viscous to be stirred efficiently and tetrahydrofuran (3 x 300 g) is added. 1H NMR analysis shows complete consumption of the acetal functionality. Solid potassium carbonate (480 g, 3.47 mol) is added and the reaction mixture is stirred at room temperature. After 18 h, stirring is stopped and the solids are allowed to settle. The solids are removed by filtration and washed with tetrahydrofuran. The filtrates are combined and the volatiles are removed by distillation at 100–115 °C, followed by vacuum drying (120 °C, 44 mm Hg). Trimethylolpropane-15-PGE(15)-GE(3) (2.73 kg, 91.0%) is obtained. 3. Triethanolamine-1,2-epoxyhexadecane(3)-PGE(15)

[0074] A round bottom flask is equipped with a heating mantle, a temperature controller, a propeller stirrer, a thermocouple, a nitrogen inlet/sparge tube, and a distillation adapter with a PTFE stopcock. Attached to the adapter is an addition funnel charged with 1,2-epoxyhexadecane (116 g, 483 mmol), a condenser, and an Erlenmeyer flask. The flask is charged under nitrogen with triethanolamine (24.0 g, 161 mmol), solid potassium methoxide (4.06 g, 0.36 mmol), and MTBE (225 g). The reaction mixture is heated to 55 °C, and distilled methyl t-butyl ether is collected. When about half of the solvent has been collected, 1,2-epoxyhexadecane is added over 8 minutes. After the epoxide addition is complete, no more solvent is collected. The reaction mixture is heated to 120 °C over 20 min. After stirring for 0.5 h, the reaction temperature is increased to 135 °C. After another 0.5 h, 1H NMR shows complete consumption of 1,2-epoxyhexadecane. The mixture cools to 110 °C.

[0075] An addition funnel charged with phenyl glycidyl ether (362 g, 2.41 mol) replaces the distillation apparatus. The glycidyl ether is added to the reaction mixture over 0.5 h. During the addition, the reaction temperature is contained at or below 130 °C. After the addition is complete, the reaction mixture is stirred at 110 °C for 4 h. 1H NMR analysis shows complete consumption of phenyl glycidyl ether. The hot reaction mixture is poured into a flask and allowed to cool. The product, triethanolamine-1,2-epoxyhexadecane(3)-PGE(15) (497 g, 98.8%) contains 0.45 wt % potassium.

4. 3[mPEG2000-PGE(6)]1-1,3,5-benzenetricarbonyl

[0076] A round bottom flask equipped with a heating mantle, temperature controller, propeller stirrer, thermocouple, and nitrogen inlet/sparge tube is charged under nitrogen with mPEG 2000 (equivalent weight = 2070 g/mol, 67.6 g, 32.6 mmol) and solid potassium methoxide (2.29 g, 32.7 mmol). The mixture is heated to 110 °C with stirring, whereupon phenyl glycidyl ether (29.5 g, 196 mmol) is added over 8 minutes. The reactant is introduced by intermittently removing the gas outlet and adding the heated liquid by pipette. During the addition, the reaction temperature is maintained at or below 120 °C by controlling both the rate of reactant addition and the rate of stirring. When the addition is complete, the reaction temperature is held at 120 °C for 100 minutes. 1H NMR analysis shows complete consumption of phenyl glycidyl ether. The mixture is cooled to 60 °C and stirred at this temperature.

[0077] Solid 1,3,5-benzenetricarbonyl trichloride (2.90 g, 10.9 mmol) is added to the flask in portions over 5 min. During the addition, the reaction temperature is contained at or below 70 °C. The mixture is stirred at 70 °C for 1 h and then at 90 °C for 1.5 h, at which point it is considered complete by 1H NMR and infrared analysis. The hot reaction mixture is decanted from the solid potassium chloride into a flask and cooled to room temperature. The product is 3[mPEG2000-PGE(6)]-1,3,5-benzenetricarbonyl (94.2 g, 93.9%). 5. Triethanolamine-PGE(15)-EO(9Q)-SA(3)

[0078] A flask is loaded with a stir bar and heated (75 °C) triethanolamine-3 [PGE(5)-EO(30)] (equivalent weight = 6363 g/mol, 10.0 g, 1.58 mmol) is added. After stirring at 75 °C for 10 min, succinic anhydride (471 mg, 4.71 mmol) is added. The anhydride is slowly introduced into the solution. After stirring for 3 h, 1H NMR analysis shows complete consumption of the succinic anhydride. The reaction mixture cools to room temperature to yield triethanolamine-PGE(15)-EO(90)-SA(3) (10.5 g, 100%).

6. Triethanolamine-PGE(18)-[SO3H(0.6)]-E0(105)-SO3H(3)

[0079] Triethanolamine-PGE(18)-EO(105) (53.9 g, 29.9 mmol) is charged to a water-jacketed reactor with the water temperature set at 60 °C. Liquid sulfur trioxide (2.92 g, 36.5 mmol) is added dropwise from an addition funnel to a flash flask under a nitrogen flow rate of about 5 L/min, and the vaporized sulfur trioxide is introduced into the reactor to maintain a reaction temperature of about 65 °C. When the addition is complete (at about 10 min), the reactor is purged with nitrogen for 5 min. The resulting acid is a highly viscous gel that is transferred to a vial and stored at -40 °C. 1H MNR analysis shows a new signal at 4.2 ppm attributed to sulfate protons and new signals at 7.3 ppm and 7.8 ppm attributed to sulfonate protons. The degree of sulfonation of arenes: about 5%.

7. Triethanolamine-PGE(18)-[SO3H(06)]-EO(105)

[0080] A mixture of the sulfate/sulfonate product described immediately above (15.0 g) is combined with water (34.8 g) and heated on a hot plate for 4 h. The sulfate groups are converted to sulfonic acid groups and the arene sulfonate groups are retained.

Polymeric Dispersant Solutions for Property Testing

[0081] The polymeric dispersant is diluted in deionized water to a concentration of 20 to 40 wt.% polymer to facilitate incorporation into a test formulation. The solutions are adjusted with acid or base to pH 8.5 to 9.5 prior to evaluation of contact angle, interfacial tension (IFT), and foaming properties.

[0082] The contact angle is measured on 0.1 wt% polymer dispersant of the invention on two types of surfaces: EMC quartz glass slides and Rinzle plastic. The measurement is conducted with a hanging drop tensiometer (Kruss DSA 20) at room temperature. The average of five measurements is recorded.

[0083] The interfacial tension of the dispersants is measured against dodecane at 0.1 wt% solids at room temperature using the hanging drop tensiometer.

[0084] Foams are tested at 0.2 wt% polymer solution in tap water. The test solution (100 g) is added to a 500 mL graduated cylinder. Foaming is kept to a minimum and the cylinder is stoppered. The cylinder is placed in a mechanical foam stirring machine and inverted 10 times. The foam is allowed to settle for 15 seconds. An initial value of the foam height is then recorded. The foam height is measured and recorded again after 5 minutes.

Pigment Dispersions

[0085] Pigment dispersions are prepared by combining the polymeric dispersants with pigments in a formulation comprising from 0.5 to 50 wt. % dispersant, from 10 to 80 wt. % pigment, from 0.5 to 6 wt. % additives (e.g., defoamer, rheology modifier, biocide, neutralizing agent, stabilizer), and from 10 to 85 wt. % water or other liquid carrier. As shown in the formulation examples below, the ratio of dispersant solids to pigment may vary over a wide range and depends on the nature of the dispersant, the nature of the pigment, the dispersing medium, and other factors. The formulation may also contain from 0 to 10 wt. % resin and from 0 to 20 wt. % solvent. Preferably, the pigment is added last to the other components of the formulation. In general, the formulation components are shaken with an equal weight of 0.8 to 1 mm glass beads in a Red Devil paint shaker for 1 to 4 hours to produce pigment dispersion. Formulation Examples: F1. Monoazo Yellow Pigment Dispersion: A polymeric dispersant of the invention (1.5 to 2.5 wt. % solids) is combined with BYK-024 defoamer (1.0 wt. % solids, product of BYK), NEOLONE® M-10 biocide (product of Dow, 0.1 wt. % solids), IRGALITE® Yellow L1254 HD (product of BASF, 50 wt. % solids) and water (q.s. to 100 wt. %). The mixture is shaken for 1 h to produce dispersion. See Tables 4, 4A and 4B. F2. Monoazo yellow pigment dispersion: The procedure of F1 is repeated with 2.6 wt. % polymeric dispersant and 53 wt. % yellow pigment solids. In this case, the mixture is stirred for 4 h to generate pigment dispersion. See Table 5. F3. Quinacridone violet pigment dispersion: A polymeric dispersant of the invention (1.2 to 6.0 wt. % solids) is combined with BYK-024 defoamer (1.0 wt. % solids), NEOLONE® M-10 biocide (0.1 wt. % solids), CINQUASIA® Red L4100 HD (BASF product, 40 wt. % solids) and water (q.s. to 100 wt. %). The mixture is stirred for 4 h to result in dispersion. See Tables 6 and 6A. F4. Quinacridone violet pigment dispersion: The procedure of F3 is repeated with 2.5 wt. % polymeric dispersant solids and 50 wt. % pigment solids. The mixture is stirred for 4 h to result in dispersion. See Table 7. F5. Phthalocyanine blue pigment dispersion (15:4): A polymeric dispersant of the invention (8.0 wt. % solids) is combined with BYK-024 defoamer (1.0 wt. % solids), NEOLONE® M-10 biocide (0.1 wt. % solids), HELIOGEN® Blue L7101 F (BASF product, 40 wt. % solids) and water (q.s. to 100 wt. %). The mixture is stirred for 2 h to result in dispersion. See Table 8. F6. Phthalocyanine blue pigment dispersion (15:3): A polymeric dispersant of the invention (6.0 to 8.0 wt. % solids) is combined with BYK-024 defoamer (1.0 wt. % solids), NEOLONE® M-10 biocide (0.1 wt. % solids), HELIOGEN® Blue L7085 F (BASF product, 40 wt. % solids) and water (q.s. to 100 wt. %). The mixture is stirred for 4 h to result in dispersion. See Table 9. F7. Phthalocyanine blue pigment dispersion (15:2): A polymeric dispersant of the invention (3.0 to 5.0 wt. % solids) is combined with BYK-024 defoamer (1.0 wt. % solids), NEOLONE® M-10 biocide (0.1 wt. % solids), HELIOGEN® Blue L6875F (BASF product, 40 wt. % solids) and water (q.s. to 100 wt. %). The mixture is stirred for 4 h to result in dispersion. See Table 10. F8. Red iron oxide pigment dispersion: A polymeric dispersant of the invention (6.0 wt. % solids) is combined with defoamer BYK-024 (1.0 wt. % solids), biocide NEOLONE® M-10 (0.1 wt. % solids), BAYFERROX® 120M (product of LanXess, 60 wt. % solids) and water (q.s. to 100 wt. %). The mixture is stirred for 2 h to result in dispersion. See Table 11. F9. Beta-naphthol orange pigment dispersion: A polymeric dispersant of the invention (3.0 to 4.0 wt. % solids) is combined with BYK-024 defoamer (1.0 wt. % solids), NEOLONE® M10 biocide (0.1 wt. % solids), MONOLITE® Orange 200504 (Heubach product, 40 wt. % solids) and water (q.s. to 100 wt. %). The mixture is stirred for 4 h to result in dispersion. See Table 12. F10. Carbon Black Pigment Dispersion: A polymeric dispersant of the invention (7.8 wt. % solids) is combined with BYK-024 defoamer (1.0 wt. % solids), NEOLONE® M10 biocide (0.1 wt. % solids), FW 200 (Orion product, 15.75 wt. % solids) and water (q.s. to 100 wt. %). The mixture is stirred for 4 h to result in dispersion. See Table 13. F11. Carbon Black Pigment Dispersion: A polymeric dispersant of the invention (variable wt. % solids) is combined with BYK-024 defoamer (1.0 wt. % solids), NEOLONE® M10 biocide (0.1 wt. % solids), MONARCH® 120 (Cabot product, 40 wt. % solids) and water (q.s. to 100 wt. %). The mixture is stirred for 4 h to result in dispersion. See Table 14.

Pigment Dispersions Test: Viscosity:

[0086] The viscosity of the pigment dispersions is measured "as is" under a shear rate of 1 to 100 s-1 at 25 °C, using a rheometer (TA Instrument). The viscosity at 10 s-1 is reported.

Particle size:

[0087] Particle size is measured in diluted dispersions of 0.1 wt% pigment using dynamic light scattering (Malvern Nanosizer) at 25 °C. Measured values are Z-average particle sizes.

Dispersion stability:

[0088] Dispersions are visually examined for uniformity and by measuring changes in viscosity as a function of time.

Resistance to wet sanding:

[0089] An interior satin base paint (Behr 7400) is painted using 40% quinacridone violet pigment dispersions containing 1.6% dispersant. The tint rate is 8 oz/gal. The colored paint is tested for wet sanding resistance in accordance with ASTM D248617, Test Method A. The paint film is sanded with a wire brush over the brass shim until a continuous line of paint is removed. The average number of sanding cycles to failure is recorded. A higher number of cycles indicates better sanding resistance.

[0090] In a control experiment with DISPERBYK® 190, the number of cycles to failure is 706. When triethanolamine-PGE(15)-EO(90) is used as the dispersant, the number of cycles to failure is 745.

Color Intensity Incorporation

[0091] Dispersion concentrates are diluted in base paint at 8 oz/gal. Behr 7400 Interior Satin Enamel Paint is used as the base paint. The resulting colored base paint is agitated for 10 minutes with a Red Devil agitator. Entrapped air is removed by gentle centrifugation before use. The colored paint is drawn with a 3 mil Bird film applicator onto a Leneta 18B pad. The wet paint film is allowed to thicken and then rubbed with a finger.

[0092] The color intensity of the dried paint film is measured with a spectrophotometer (Minolta) using the CIE L* a* b* system or, alternatively, the L* C* h. The color intensity can also be represented by Chroma C*.

[0093] If the pigment is not well dispersed or is separated, the mechanical motion of the friction will re-disperse the pigment and make the color of the paint film stronger and more homogeneous. By comparing the color difference, AE, between the rubbed area and the non-rubbed area, the quality of the pigment dispersion can be revealed. The target is to have no color difference or minimal color difference of AE, where AE has been defined as: where ΔL, Δa and Δb refer to differences in light/dark, red/green and yellow/blue, respectively. See Tables 16, 17 and 18 for results. The dispersants of the invention perform as well as or better than the control.

Blocking resistance:

[0094] Blocking resistance evaluates the adhesion and face-to-face of a film. The test is conducted in accordance with ASTM D4946-89. Blocking resistance is rated based on how well the paint film is sealed or tacky. A higher rating indicates adhesion or sealing. An interior satin base paint (Behr 7400) is colored at 8 oz/gal by preparing pigment dispersions using the dispersant of the invention and a control dispersant, both at the optimum dispersant concentrations. Table 20, below, shows that the dispersant of the invention has better blocking resistance compared to the control.

Universal compatibility:

[0095] The polymer dispersants of the invention demonstrate surprising universal compatibility and tinting ability for both water-based and solvent-based paints. An oil-based alkyd paint (Behr 3800) is tinted with the water-based pigment dispersions at 12 oz/gal. In most cases, the 5 dispersants of the invention show much higher Chroma values compared to the control, indicating better compatibility and strong colors after tinting the oil-based white paint. The results are shown in Table 21.

[0096] The contact angle data show that the copolymers of the invention can wet both hydrophilic and hydrophobic surfaces. The interfacial tension data also demonstrate that the copolymers are potentially useful as emulsifiers because they can decrease the IFT between dodecane and water from about 53 mN/m to less than 20 mN/m in most cases.

[0097] A dispersant that provides low or unstable foam is desirable for paints and other dispersion products. Some of the copolymers of the invention, e.g., the morpholine-initiated dispersants, show surprisingly rapid foam dissipation compared to control samples.

[0098] The examples in Table 16 are dispersions made in a VOC-free formulation with water as the sole solvent. The dispersants of the invention perform as well or better than the control.

[0099] In some cases, a small proportion of solvent can aid in the film-forming properties of a paint or coating, as in the formulation examples shown in Table 19.

Performance in agricultural formulations 1. Wettable powders

[0100] The copolymers of the invention are evaluated as dispersants for wettable powder formulations with three agricultural actives: atrazine, chlorothalonil and imidacloprid.

[0101] Samples are prepared by combining 80 to 95 wt.% agricultural active, 0.1 to 5 wt.% wetting agent and 0 to 10 wt.% additives (e.g. antifoaming agent, clay). The mixture is ground to a desired particle size (5 to 30 μm). A dispersant solution is made by combining the polymeric dispersant (0.1 g) with water (50 mL). The ground active formulation (1.0 g) is added to the dispersant solution and the resulting mixture is diluted to volume in a 100 mL graduated cylinder. The cylinder is inverted 15 times and evaluated after 0.5 h, 1 h, 2 h and 24 h for the degree of separation. The results are shown in Table 22. In each case, the copolymer of the invention performed as well as the control surfactant, STEPFAC® TSP-PE N (a phosphate salt of tristyrylphenol ethoxylate). Formulations: a. Atrazine (92.0 wt %); STEPWET® DF-90 wetting agent (Stepan's product, 1.0 wt %); dispersant (7.0 wt %), see Table 22. b. Chlorothalonil (92.8 wt %); STEPWET® DF-90 wetting agent (1.0 wt %); dispersant (6.2 wt %), see Table 22. c. Imidacloprid (73.7 wt %); STEPWET® DF-95 wetting agent (Stepan's product, 0.5 wt %); RUBBERSIL™ RS200 precipitated silica (product of Glassven C.A., 0.5% by weight); kaolin clay (19.3% by weight); dispersant (6.0% by weight, see Table 22).

2 Suspension concentrates

[0102] The copolymers of the invention are evaluated as dispersants for suspension concentrate formulations with two agricultural actives: tebuconazole and imidacloprid. The tebuconazole formulations are evaluated for initial and two-week suspendability. All of the copolymers of the invention tested performed well in this test. The imidacloprid samples were evaluated for two weeks for oven suspendability and freeze-thaw suspendability (five cycles).

[0103] Suspension concentrates were prepared by combining the copolymer dispersant (0.5 to 3.5 wt. %), agricultural active (20 to 60 wt. %), additives (e.g. rheology modifier, antifoaming agent, antifreeze agent, biocide; 0.1 to 10 wt. %) and water (25 to 75 wt. %). The ratio of dispersant solids to active ingredient may vary over a wide range and depends on the nature of the dispersant, the nature of the active ingredient and other factors. Preferably, the active ingredient is added last to the other formulation components. In general, the formulation components are wet milled to the desired particle size d50 of 1 to 3 μm. The rheology modifier may be incorporated following the milling process. Formulations: a. Tebuconazole (45.0 wt. %); wetting agent STEPFLOW® 26F (product of Stepan, 1.0 wt. %); dispersant (2.0 wt. %); antifoaming agent SAG™ 1572 (product of Momentive Performance Materials, 0.20 wt. %); propylene glycol (5.0 wt. %); 2% xanthan solution (10.0 wt. %) and water (36.8 wt. %); b. Imidacloprid (20.0 wt%; wetting agent STEPFLOW® 26F (1.3 wt%); dispersant (2.70 wt%); antifoaming agent SAG™ 1572 (0.20 wt%); propylene glycol (5.0 wt%); 2% xanthan solution (10.0 wt%), nonionic surfactant TOXIMUL® 8240 (Stepan's product, 2.0 wt%) and water (58.8 wt%).

Assessment of suspensibility:

[0104] A suspension concentrate formulation (10 g) is added to a 250 mL graduated cylinder containing 1000 ppm TDS water (200 mL). The sample is diluted to volume and inverted 15 times. After 0.5 h, the top 225 mL is removed using a vacuum apparatus. The remaining solution is transferred to a tared dish and allowed to dry for measurement of the weight of unsuspended solids. Additionally, a sample of the suspension concentrate formulation is measured for solids content using an oven at 50 °C to identify the percentage of suspended solids in the diluted solution. The results appear in Table 23.

[0105] The above examples are for illustration only; the following claims define the scope of the invention.

Claims (8)

1. A copolymer comprising a reaction product of: (a) a monofunctional nucleophilic initiator selected from the group consisting of thiols, thiophenols, aralkylated phenols, sulfinic acids, secondary amines, C10-C20 terpene alcohols and deprotonated species thereof; (b) from 1 to 30 recurring units per equivalent of active hydrogen of the initiator of a phenyl glycidyl ether; and (c) from 1 to 100 recurring units per equivalent of active hydrogen of the initiator of one or more alkylene oxides (AO) selected from the group consisting of ethylene oxide, propylene oxide, butylene oxides, and combinations thereof, wherein the copolymer comprises from 20 to 60% by weight of the recurring units of phenyl glycidyl ether based on the combined amounts of the phenyl glycidyl ether and recurring AO units; and wherein the copolymer has a number average molecular weight in the range of from 900 to 12,000 g/mol. 2. Copolymer, according to claim 1, characterized by the fact that the monofunctional nucleophilic initiator is a complex initiator comprising a hydroxy functional reaction product of an epoxide or a glycidyl ether with a monofunctional nucleophile selected from the group consisting of alcohols, phenols, amines, thiols, thiophenols, sulfinic acids and deprotonated species thereof. 3. Dispersing composition characterized by the fact that it comprises water and the copolymer as defined in claim 1. 4. Dispersion characterized by the fact that it comprises a pigment, water, a pH adjusting agent and the copolymer as defined in claim 1. 5. Wettable polymer composition characterized by the fact that it comprises from 80 to 95% by weight of at least one agricultural active, from 0.1 to 5% by weight of an anionic surfactant, and from 1 to 20% by weight of the copolymer as defined in claim 1. 6. Suspension concentrate characterized by the fact that it comprises from 20 to 60% by weight of at least one agricultural active ingredient, from 25 to 75% by weight of water, and from 0.5 to 3.5% by weight of the copolymer as defined in claim 1. 7. Water-dispersible granule or film coating characterized by the fact that it comprises an agricultural active ingredient and the copolymer as defined in claim 1. 8. A method for making a dispersant comprising: (a) reacting a di- or polyfunctional glycidyl ether with a monofunctional nucleophilic initiator selected from the group consisting of alcohols, secondary amines, and thiols to yield a hydroxy-functional intermediate; (b) reacting the intermediate with 1 to 30 equivalents of a phenyl glycidyl ether to yield a hydrophobe; and (c) reacting the hydrophobe with 1 to 100 equivalents of one or more alkylene oxides (AO) selected from the group consisting of ethylene oxide, propylene oxide, butylene oxides, and combinations thereof.