MXPA97001484A - Acid dispersant polyalykenglycol hydroxycarboxyl - Google Patents

Abstract

This invention relates to novel polymeric compounds, more particularly to novel block or graft copolymers, which are useful for dispersing inorganic pigments. lacquers and / or black resinous pigments in an organic medium, to methods for preparing such copolymers, and to surfactant compositions containing such polymers. The block or graft copolymers of the invention belong to the class in which one type of polymer component is derived from a monocarboxylic acid of oil-soluble complex and another component which is the residue of an alkyl glycol and / or polyoxyalkylene compounds

Description

ACID DISPERSANT POLYGEN CHYLENGLYCOL HYDROXY CARBOXYLIC DESCRIPTION OF THE INVENTION This invention relates to novel polymeric compounds, more particularly to novel block or graft copolymers, which are useful in the dispersion of inorganic pigments, lacquers and / or black resinous pigments in an organic medium, to methods for preparing such copolymers, and surfactant compositions containing such "polymers." The block or graft copolymers of the invention belong to the class in which one type of the polymer component is derived from a monocarboxylic acid of oil-soluble complex, and another component, which is the residue of alkylglycol and / or polyalkylene compounds Certain members of this class are already known from British Patent No. 1,469,531, which refers to copolymers consisting of a single block derived from the complex acid and from a single block , which is the residue of a polyalkylene glycol, and U.S. Patent 4,203,877, which refers to copolymers derivatives of an oil soluble complex monocarboxylic acid, having a molecular weight of more than 500, and a water-soluble polyoxyalkylene-containing compound having a molecular weight of at least 500. However, these copolymers possess useful properties of surfactant agent, have structural and chemical composition limitations, which restrict the ability to select a composition that offers optimal surface active characteristics for a given system. In addition, copolymers of this type tend to be waxy or solid compositions, which not only limit their application capacity, but also complicate their handling capacity by requiring drum heaters and other special handling equipment. While, the copolymers of the present invention, which tend to be liquid, overcome these disadvantages. Accordingly, an aspect of the invention is to provide a compound useful for dispersing inorganic pigments, lacquers and / or black resinous pigments in an organic medium. Another aspect of the invention is to provide a liquid, high molecular weight surfactant compound. It is a further aspect of the invention to provide a suitable surfactant composition for forming a dispersion of inorganic pigments, lacquers or black resinous pigments in an organic medium.

Another advantage of the copolymers of the present invention is that they are liquid, despite the fact that they typically have higher molecular weights than the waxy / solid copolymers known in the art, and thus have an improved handling capacity. A further aspect of the present invention is to provide a method for forming a polymeric compound formed from a monocarboxylic acid of an oil-soluble complex and an alkyl glycol and / or polyalkylene glycol. The above aspects and other additional aspects of the invention will be more apparent from the following description and from the appended Examples.

DETAILED DESCRIPTION OF THE INVENTION The copolymer of this invention has the general formula (A-COO) 2"* B # wherein each polymer component A has a molecular weight of at least 500, and is the residue of an oil soluble complex monocarboxylic acid having the following general structural formula: wherein R is hydrogen or a monovalent hydrocarbon or substituted hydrocarbon group; R1 is hydrogen or a monovalent hydrocarbon group of C1 to C24; R2 is a divalent hydrocarbon group of C- ^ a C24; p is an integer from 1 to 200; and wherein each polymer component B has a molecular weight less than 500, and is the divalent residue of an alkyl glycol or polyalkylene glycol having the structure of the following general formula: wherein R3 may be the same or different, and is selected from the group consisting of hydrogen, methyl, ethyl and propyl; q is an integer from 1 to 11 s is an integer from 1 to 17. The amount of qys will usually vary statistically around an average value within the established scale, and a slightly broader variation can be deliberately entered, if desired , deriving component B from a mixture of two or more glycols or chain lengths of different average. The complex monocarboxylic acid, from which the polymeric components A are derived by the notional removal of the carboxyl group, is structurally the interesterification product of one or more monohydroxymonocarboxylic acids, together with a monocarboxylic acid free of hydroxyl groups, which acts as a chain terminator. The substituted or unsubstituted hydrocarbon chains R, R- ^ and R2 may be linear or branched. R is preferably an alkyl radical containing up to 25 carbon atoms, for example a straight chain 17H35 radical derived from stearic acid. R-j ^ is preferably a straight-chain alkylene radical; for example, the unit containing R. ^ and R2 may be derived from 12-hydroxy-stearic acid. The alkyl glycol and / or polyalkylene glycol from which the polymer component B is derived by notional removal of the two hydroxyl end groups, may be, for example, ethylene glycol, propylene glycol, other alkyl glycols (ie, C4-C5), a polyethylene glycol , a polypropylene glycol, mixtures or combinations thereof, that is, R3 may be hydrogen, methyl, ethyl or propyl. More typically, component B is derived from polyethylene glycol or 1,4 butanediol.

By defining that the complex monocarboxylic acid is soluble in oil, it is meant that the oil phase of the system, in which the block or graft copolymer is to be used as a surfactant, should be better than a teta-solvent for the complex monocarboxylic acid. The meaning of the term "teta-solvent" is discussed in "Polymer Handbook" (Ed. Brandrup and Immergut, Interscience, 1966) in Vol. VI pages 163-166. In summary, this definition implies that a polymer that dissolves in a solvent, which is better than a teta-solvent, therefore exists in a non-self-associated condition. The definition is usually satisfied by any liquid that can normally be mastered as a "good" solvent for the polymer in question. A considerable variation in the composition of the complex monocarboxylic acid is possible, as long as it satisfies the requirement that the acid must be soluble in oil in the above sense, according to the chosen nature of the group R, RI and R2 • Generally speaking, between The more oil phase of the system stores towards a totally aliphatic character, the longer the hydrocarbon chains of these groups need to be. Typically, each of the polymer components A has a molecular weight of at least 1000 (by "molecular weight" it is meant the number average molecular weight), preferably a molecular weight of 1500, and more preferably a molecular weight of molecular weight in excess of 1750. In this way, where for example the R group is derived from stearic acid and the unit containing R and R2 together, derived from 12-hydroxystearic acid "p" will have a value of less 2. Typically it is required that the polymer component B have a molecular weight (by "molecular weight" is meant to mean number-average molecular weight) of less than 500, more typically a molecular weight of 50 to 450, and preferably a molecular weight of 70 up to and including 400. Thus, when the "B" component is the residue of an alkyl glycol, such as when "q" is equal to 1, "s" will typically have a value of at least 5. , but less than 17, preferably less than 5, d e greater preference 2 or 3; or when said component is derived from a polyalkylene glycol, when "q" has a value of at least 2, typically between 2 and 9, preferably between 4 and 9; "s" preferably will have a value of 1. In any given block or graft copolymer of the general formula defined above, the weight ratio of the combined components A to component B may vary widely. Typically, the molar ratio will lie on the scale of 125: 1 to 2: 1, more typically the ratio is on the scale of 17: 1 and 8: 1; but molar ratios outside these scales may be appropriate for certain applications of the copolymers. In block copolymers A-COO-B-OOC-A, wherein component B is derived from polyethylene glycol, and components A are derived from poly-12-hydroxystearic acid, the weight ratio of the polyethylene glycol residues can be up to of 20%, but more typically they are between 4% and 12%. The block or graft copolymers of the invention can be obtained by methods that are well known in the art. According to a procedure, they are prepared in two stages. In the first step, the complex monocarboxylic acid, from which the A components are derived, is obtained by the interesterification of a monohydroxy monocarboxylic acid in the presence of a non-hydroxylic-monocarboxylic acid; in the second stage, this complex monocarboxylic acid is reacted with the alkyl glycol or polyalkylene glycol, from which the component B is to be derived, in a molar ratio of 2: 1, respectively. The hydroxyl group in monohydroxy monocarboxylic acid, and the carboxyl group in any carboxylic acid, may be primary, secondary or tertiary, in character. Suitable hydroxycarboxylic acids for use in the first stage include glycolic acid, lactic acid, hydracrylic acid, and, in particular, 12-hydroxystearic acid. The non-hydroxylic carboxylic acid, which acts as a chain terminator, and therefore as a means for regulating the molecular weight of the complex monocarboxylic acid, can be, for example, acetic acid, propionic acid, caproic acid, in particular, stearic acid or an acid derived from an oil of natural existence, such as fatty acid from bait oil. Commercial quantities of 12-hydroxystearic acid, usually containing about 15% stearic acid, can be used as an impurity and can be conveniently used without further mixing to produce a complex acid with a molecular weight of about 1500-2000. If the non-hydroxylic monocarboxylic acid is introduced separately, the proportion at which it is required, in order to produce a complex monocarboxylic acid of a given molecular weight, could be known to one skilled in the art or easily determined by simple calculation . The interesterification of the monohydroxy monocarboxylic acid and the non-hydroxylic monocarboxylic acid can be effected by heating the starting materials, alone, or in a suitable hydrocarbon solvent such as toluene or xylene, which is capable of forming an azeotrope with the water produced in the esterification reaction. These reactions are typically carried out in an inert atmosphere, for example nitrogen, at a temperature of up to 250 ° C, conveniently at the reflux temperature of the solvent. If the hydroxyl group is secondary or tertiary and the temperature used should not be so high to lead to dehydration of the acid molecule. Catalysts for interesterification may be included, such as p-toluenesulfonic acid, zinc acetate, zirconium naphthenate or tetrabutyl titanate, in order to increase the reaction rate at a given temperature or to reduce the temperature required for a given velocity. of reaction. A preferred method for performing the interesterification is to carry out the reaction at an elevated temperature, without xylene, but using a stream of inert gas to remove the produced water. The process produces products, which are 100% solids and do not contain environmentally friendly xylene. In the second step of the first method, to obtain the block or graft copolymers of the invention, the complex monocarboxylic acid prepared in the first step is reacted with the alkyl glycol or polyalkylene glycol, from which the component B is to be derivative. For each molar proportion of glycol, 2 molar proportions of the acid are taken. The reaction is suitably carried out under the same conditions described for the first stage.

According to the second method for obtaining the copolymers of the invention, the two reactions described above are carried out simultaneously, that is, the monohydroxy monocarboxylic acid, the non-hydroxylic monocarboxylic acid and the alkyl glycol or polyalkylene glycol are heated together in the same proportions as if they had been taken for the first procedure, in a hydrocarbon solvent at a temperature of up to 250 ° C, optionally in the presence of a catalyst and observing the precautions. The copolymers obtained by the two alternative processes, from the same starting materials and in the same proportions, appear to be very similar in composition and characteristics, but due to their simplicity and more consistent economy, the second method is preferred. The novel block or graft copolymers of the invention are particularly useful by virtue of their pronounced surface active properties. Therefore, they are highly effective, such as, for example, wetting and dispersing agents. The novel block or graft copolymers of this invention are suitable for dispersing inorganic pigments, lacquers and / or black resinous pigments in organic solvents. Suitable inorganic pigments include: Prussian blue, cadmium sulfide, iron oxides, vernum, ultramarine and chromium pigments, including lead, zinc, barium and calcium chromates; more typically, calcium carbonate, aluminum trihydrate, titanium dioxide. Black resinous pigments and lacquers include those of the water-insoluble metal salt complex. An example of a particular block or graft copolymer according to the invention is a block copolymer of (A-COO) 2-B wherein each A component is the residue of poly-12-hydroxystearic acid-terminated chain acid stearic and with a molecular weight of about 1750, and component B is the polyethylene glycol residue with a molecular weight of less than 500. This copolymer, in this way, contains about 8% by weight of polyethylene glycol residues and is soluble in organic solvents , aliphatic and aromatic solvents, hydrocarbon oils, toluene, including those with a low aromatic content, such as low-order kerosene, diesel oil and mineral oils. The invention can be better understood by reference to the following specific examples, which teach various embodiments of this invention.

EXAMPLE 1 Preparation of a block or graft copolymer of the type (A-COO) 2 ~ B containing 5.4% by weight of polyethylene glycol residues with a molecular weight of 200 in a single step. Approximately 2818 parts of a commercial grade 12-hydroxystearic acid containing 15% stearic acid, available from Caschem, Inc., Bayonne, NJ. , were introduced into a 5000 ml flask together with approximately 160.8 parts of polyethylene glycol with a molecular weight of 200, and approximately 5.95 parts of tetrapropyl titanate. Everything was reacted together at 225 ° C, in the presence of nitrogen gas, until an acid value of about 9.3 mg KOH / g was obtained.

EXAMPLE 2 A block copolymer similar to that described in Example 1 was prepared, but containing 10.2% polyethylene glycol residues, in the manner described in Example 1, from 300 parts of polyethylene glycol with a molecular weight of 400, 2630 parts of commercial grade 12-hydroxystearic acid, and 6.0 parts of tetrapropyl titanate; the product was condensed to an acid value of 9.0 mg KOH / g.

Claims (15)

1. A copolymer of the general formula (A-COO) 2-B, characterized in that A has a molecular weight of at least 500, and is a residue of an oil soluble complex monocarboxylic acid having the general structural formula: wherein R is hydrogen or a monovalent hydrocarbon or substituted hydrocarbon group; R-L is hydrogen or a monovalent hydrocarbon group R2 is a divalent hydrocarbon group of C- ^ a C24; p is an integer from 1 to 200; and wherein each polymer component B has a molecular weight less than 500, and is the divalent residue of an alkyl glycol or polyalkylene glycol having the structure of the following general formula: wherein R3 may be the same or different, and is selected from the group consisting of hydrogen, methyl, ethyl and propyl; q is an integer from 1 to 11 s is an integer from 1 to 17.

2. A copolymer according to claim 1, characterized in that R is hydrogen or a monovalent substituted hydrocarbon group of C ^ _ to C24; R- is hydrogen or a monovalent substituted hydrocarbon group of C- ^ to C24; R2 is a divalent substituted hydrocarbon group from 1 to 24 *

3. A copolymer according to claim 1, characterized in that the component A has a molecular weight of at least 1000.

4. A copolymer according to claim 1, characterized in that each component A is derived from poly-12-hydroxystearic acid chain terminated with stearic acid and component B is derived from polyethylene glycol.

5. A copolymer according to claim 4, characterized in that component B has a molecular weight of 50 to 450.

6. A copolymer according to claim 5, characterized in that "q" is at least 2 and "s" is 1.

7. A copolymer according to claim 1, characterized in that each polymer component has a molecular weight of about 1750, and component B has a molecular weight of about 200 and component B comprises between 4% and 12% by weight of the total copolymer .

8. A copolymer according to claim 1, characterized in that component B is derived from propylene glycol or 1,4-butanediol.

. A copolymer according to claim 8, characterized in that it is soluble in aliphatic hydrocarbons and wherein the component B constitutes more than 20% by weight of the total copolymer.

10. A copolymer of the general formula (A-COO) 2 ~ B, characterized in that A has a molecular weight of at least 500 and is derived from poly-12-hydroxystearic acid chain terminated with stearic acid; and B is derived from polyethylene glycol having a molecular weight of from 70 to 400.

11. A method for preparing a copolymer of the general formula (A-COO) 2-B, wherein A has a molecular weight of at least 500, and is a residue of an oil-soluble complex monocarboxylic acid having the general structural formula : wherein R is hydrogen or a monovalent hydrocarbon or substituted hydrocarbon group; R, is hydrogen or a monovalent hydrocarbon group R2 is a divalent hydrocarbon group of C_ -24 p is an integer from 1 to 200; and wherein each polymer component B has a molecular weight less than 500, and is the divalent residue of an alkyl glycol or polyalkylene glycol having the structure of the following general formula: Ho - - (CHCHj), - O wherein R3 may be the same or different, and is selected from the group consisting of hydrogen, methyl, ethyl and propyl; q is an integer from 1 to 11 s is an integer from 1 to 17, characterized in that the method comprises the following steps: i) reacting a monocarboxylic acid, from which component A is derived in the presence of a non-monocarboxylic acid hydroxylic to form a complex monocarboxylic acid; ii) further reacting the complex monocarboxylic acid with alkyl glycol or polyalkylene glycol, from which component B is derived, in a ratio of 2: 1.

12. The method according to claim 11, characterized in that the reactions are carried out in the presence of an inert gas at an elevated temperature.

13. The method in accordance with the claim 12, characterized in that the two reactions are performed simultaneously.

14. The method in accordance with the claim 13, characterized in that the two reactions are carried out in the presence of a catalyst.

15. An organic composition, characterized in that it comprises: in addition to an organic solvent; i) A copolymer of the general formula (A-COO) 2-B, wherein A has a molecular weight of at least 500 and is a residue of an oil-soluble complex monocarboxylic acid having the general structural formula: wherein R is hydrogen or a monovalent hydrocarbon or substituted hydrocarbon group; R- ^ is hydrogen or a monovalent hydrocarbon group R2 is a divalent hydrocarbon group of C- ^ a -24 p is an integer from 1 to 200; and wherein each polymer component B has a molecular weight less than 500, and is the divalent residue of an alkyl glycol or polyalkylene glycol having the structure of the following general formula: wherein R3 may be the same or different, and is selected from the group consisting of hydrogen, methyl, ethyl and propyl; q is an integer from 1 to 11 s is an integer from 1 to 17; and ii) inorganic pigments, lacquers and / or black resinous pigments.