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WO1992015535A1 - Acide polyaspartique et ses sels pour la dispersion de solides en suspension - Google Patents

Acide polyaspartique et ses sels pour la dispersion de solides en suspension Download PDF

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Publication number
WO1992015535A1
WO1992015535A1 PCT/US1992/001704 US9201704W WO9215535A1 WO 1992015535 A1 WO1992015535 A1 WO 1992015535A1 US 9201704 W US9201704 W US 9201704W WO 9215535 A1 WO9215535 A1 WO 9215535A1
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WO
WIPO (PCT)
Prior art keywords
finely divided
divided solid
aqueous suspension
solid particles
temperature
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/US1992/001704
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English (en)
Inventor
Larry Paul Koskan
Kim C. Low
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Donlar Corp
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Donlar Corp
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Filing date
Publication date
Application filed by Donlar Corp filed Critical Donlar Corp
Publication of WO1992015535A1 publication Critical patent/WO1992015535A1/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

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Classifications

    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J3/00—Processes of treating or compounding macromolecular substances
    • C08J3/02—Making solutions, dispersions, lattices or gels by other methods than by solution, emulsion or suspension polymerisation techniques
    • C08J3/03—Making solutions, dispersions, lattices or gels by other methods than by solution, emulsion or suspension polymerisation techniques in aqueous media
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
    • C09D17/00—Pigment pastes, e.g. for mixing in paints
    • C09D17/004—Pigment pastes, e.g. for mixing in paints containing an inorganic pigment
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
    • C09K23/00—Use of substances as emulsifying, wetting, dispersing, or foam-producing agents
    • C09K23/16—Amines or polyamines
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
    • C09K23/00—Use of substances as emulsifying, wetting, dispersing, or foam-producing agents
    • C09K23/28—Aminocarboxylic acids
    • C—CHEMISTRY; METALLURGY
    • C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
    • C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
    • C11D17/00—Detergent materials or soaps characterised by their shape or physical properties
    • C11D17/0008—Detergent materials or soaps characterised by their shape or physical properties aqueous liquid non soap compositions
    • C11D17/0013—Liquid compositions with insoluble particles in suspension
    • C—CHEMISTRY; METALLURGY
    • C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
    • C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
    • C11D3/00—Other compounding ingredients of detergent compositions covered in group C11D1/00
    • C11D3/16—Organic compounds
    • C11D3/37—Polymers
    • C11D3/3703—Macromolecular compounds obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
    • C11D3/3719—Polyamides or polyimides

Definitions

  • Examples of the different types of scale and particulates dispersed would include CaC0 3 , CaS0 4 , BaSO Region, Fe 2 0 3 , clays such as Kaolin, Ti0 2 , Zn(0H) 2 , Ca 3 (P0) 4 , Mg(0H) 2 , Mn 2 0 3 and many others.
  • dispersants used today are of a synthetic variety, usually a water soluble polymer made from acrylic acid, acrylamide, their derivates, maleic acid, vinyl esters, and the like. These polymers are non-biodegradable and potentially toxic to the environment.
  • Starch and lignin based dispersants although biodegradable, tend to be poorer performers compared to their polyacrylate counterparts.
  • Water soluble salts of polyaspartic acid are excellent agents for suspending in water a variety of inorganic and organic particles. Due to the biodegradability of polyaspartic acid it is acceptable for use in a variety of industrial products and processes.
  • FIGURE 1 depicts a temperature versus time reaction curve.
  • Series 1 is the oil temperature.
  • Series 2 is the reaction mixture temperature.
  • FIGURE 2 depicts a temperature versus time reaction curve.
  • Series 1 is the oil temperature.
  • Series 2 is the reaction mixture temperature.
  • FIGURE 3 depicts a temperature versus time reaction curve.
  • Series 1 is the oil temperature.
  • Series 2 is the reaction temperature.
  • FIGURE 4 depicts a temperature versus time reaction curve.
  • Series 1 is the oil temperature.
  • Series 2 is the reaction temperature.
  • FIGURE 5 depicts a temperature versus time reaction curve.
  • Series 1 is the oil temperature.
  • Series 2 is the reaction mixture temperature.
  • the starting polysuccinimides from which the polyaspartic acids are synthesized are produced by the thermal condensation of powdered L-aspartic acid to produce polysuccinimide in high yields.
  • yield means theoretical yield based on the starting molecular weight of the aspartic acid. These yields optimally occur above the initiation temperature of about 370 °F and preferably occurs above 420 °F, and most preferably occurs above 440 °F.
  • a reactant temperature less than 370 °F may produce polysuccinimide over a period of many hours.
  • Theoretical yields will be low; the conversion of the L-aspartic acid to polysuccinimide will be less than 70% and will require a period of many days.
  • the thermal condensation of L-aspartic acid to polysuccinimide using the above reaction conditions produces a characteristically shaped "temperature vs. time" reaction curve.
  • the curve is characterized by an initial, rapid rise in reactant temperature, followed by an endotherm signally the beginning of the reaction. Immediately following the onset of the endotherm there is evaporative cooling, followed first by a temperature rise, and then by a second endotherm, which is followed by an evaporative cooling plateau. The temperature then rises to a plateau. That plateau is at a constant temperature. The reaction has gone to at least 95% conversion at the temperature midway between the final plateau and the time the temperature begins to rise to that plateau.
  • the color of each product sample was noted.
  • the color of L-aspartic acid is white.
  • Polysuccinimides vary in color according to the temperature of the sample taken during the course of the reaction. From low temperature to high, the colors vary as follows: light pink, to pink, to tannish pink, to tan, to light yellow, to yellow. These colors generally correspond to the percent conversion of the L- aspartic acid, in the same order with light pink indicating the lowest percent conversion and yellow indicating the highest percent conversion. The pink colors had less than 70 % conversion.
  • the literature has never reported any other color but pink.
  • the polysuccinimides used in the practice of this invention should be free of pure pink color.
  • the polysuccinimides used to prepare the polyaspartic acid dispersants of this invention have a water content less than 1%, and they usually are substantially water-free.
  • the conversion of L-aspartic acid to polysuccinimide was determined as follows: A specific amount of the reaction mixture or product was dissolved in an aliquot of dimethylformamide (DMF). The dissolution was allowed to proceed for 4 to 5 hours until all of the polysuccinimide dissolved in the DMF leaving unreacted L-aspartic acid which was filtered out.
  • DMF dimethylformamide
  • the amount of unreacted L-aspartic acid was determined by using the following formula:
  • the percent conversion of the L-aspartic acid to the polysuccinimide in the reaction can be increased in reduced time periods by increasing the temperatures used.
  • thermal fluid is used to heat the L-aspartic acid and as its temperature is brought to a maintenance temperature of at least 550 ⁇ F in a reasonable time period, at least 90% conversion can be effected within 4 hours.
  • thermal fluid used to heat the L-aspartic acid is brought to a maintenance temperature of at least 550 °F within a reasonable time period, at least 90% conversion can be effected within 2 hours.
  • Continuous and batch processes can be used. Some process examples include fluidized bed, stirred reactor, and indirectly heated rotary driers.
  • temperatures between 420-520 °F produces polysuccinimide at yields greater than 80%.
  • temperatures between 420-450 °F 90% conversions will be obtained.
  • 500 °F will produce a 90% conversion in 4 hours and 510 °F will produce a 90% conversion in 1 1/2-2 hours.
  • the reaction began when the first endotherm was reached.
  • the first endotherm of the reaction mixture peaked at 395 °F at an oil temperature of 439 °F.
  • the color of the reaction mixture is provided. Color was observed to vary with product temperature.
  • the reaction began when the first endotherm was reached.
  • the first endotherm of the reaction mixture peaked at 405 °F at an oil temperature of 465 °F.
  • Table 2 below provides data developed during this experiment. Samples were taken at the times indicated and analyzed for percent conversion to polysuccinimide.
  • the color of the reaction mixture is provided. Color was observed to vary with product temperature.
  • the reaction began when the first endotherm was reached.
  • the first endotherm of the reaction mixture peaked at 410 °F at an oil temperature of 470 °F.
  • the color of the reaction mixture is provided. Color was observed to vary with product temperature.
  • a DVT-130 drier, mixer manufactured by the Littleford Brothers, Inc., of Florence, Kentucky was used.
  • the jacketed drier utilizes a thermal fluid (hereinafter called "oil"), a plough blade impeller, a stack open to the atmosphere; and has a heat transfer area of 10 ft 2 .
  • the reactor's oil reservoir was preheated to 550 °F.
  • the reactor was charged with 110.4 lb of powdered, L-aspartic acid. Hot oil began to flow through the jacket, and the impeller speed was set at 155 rpm. Both the product and oil temperatures rose steadily. At a product temperature of 390 °F, there was a sudden, endothermic reaction which caused the product temperature to drop (see Fig. 4). Water loss was evidenced by the evolution of steam. A sample taken revealed that the powder had changed from white to pink. Three percent of the material was converted to polysuccinimide.
  • Table 4 below provides data developed during this experiment. Samples were taken at the times indicated and analyzed for percent conversion to polysuccinimide.
  • Polysuccinimides may be produced using the steps of a) . heating powdered L-aspartic acid to at least 370 ⁇ F to initiate the condensation reaction, then b). raising the reaction mixture temperature to at least 420 °F, and c) . maintaining at least the 420 °F temperature until at least 80% conversion has occurred.
  • reaction mixture temperature is raised to at least 430 °F for a sufficient period of time a 90 % conversion can be achieved.
  • reaction mixture temperature is raised to at least 440 °F for a sufficient period of time a 95% conversion can be achieved.
  • Polyaspartic acid is produced from polysuccinimide using the following hydrolysis procedure: A slurry is made from a measured amount of polysuccinimide and distilled water. Sodium hydroxide is added dropwise to hydrolyze polysuccinimide to polyaspartic acid. The completion of the hydrolysis is attained at pH 9.5.
  • Bases other than sodium hydroxide can be used. Suitable bases include ammonium hydroxide, potassium hydroxide, and other alkaline and alkaline earth hydroxides.
  • base should be added to the slurry until the pH has been raised to 9.5, and a clear solution has been formed.
  • the pH may be adjusted to higher levels. Between pHs ranging between 11 and 12, the polaspartic acid solutions have a bright yellow color. These higher pH solutions are useful when compatibility with higher pH slurries is required.
  • Polyaspartic acids are made up of alpha and beta peptide bonds.
  • the polyaspartic acids used as dispersants to practice this invention contain between 50% to about 75% of beta peptide groups.
  • the preferred dispersants usually contain 60% to 75% of beta peptide bonds.
  • polyaspartic acid used herein and in the claims means the salts of polyaspartic acid.
  • Counterions for polyaspartate include, but are not limited to, the alkaline and alkaline earth cations, some examples of which are Na + , K + , Mg + , and Li + , Ca ++ , Zn ++ , Ba ++ , Co ++ , Fe ++ , Fe +++ , and NH4 + .
  • the free acid is very water soluble therefore making it of extended applicability as a dispersant.
  • MOLECULAR WEIGHT DETERMINATION The polyaspartic acid dispersant of this invention has a weight average molecular weight of 1000 to 5000.
  • the suspended solids capable of being effectively suspended b y the polyaspartic acid salts include a wide variety of both inorganic and organic particles. 1. THE INORGANIC PARTICLES
  • alumino-silicates which encompass a wide number of clays.
  • the alumino-silicates also include a large number of inorganic ion exchange materials illustrated by the base exchange clays and the synthetic zeolites illustrated by the molecular seives. It is obvious to those skilled in the art that certain of the alumino-silicates described above contain elements other than aluminum, silicon, and oxygen. When such additional elements are present for instance, magnesium, the solids are considered to be alumino-silicates.
  • a particlularly broad class of inorganic particles capable of being suspended by the polyaspartic acid salts may be generically described as pigments.
  • Illustrative of such materials are the finely divided particles calcium carbonate, titania, and silica. These materials find use in the form of aqueous suspension in the manufacture of paints, paper, ceramic slurries and many other well known commercial products.
  • the invention is particularly useful in its ability to produce stabilized iron oxide suspensions.
  • These particles include a wide variety of organic materials illustrated by such materials as dirt, which includes silt.
  • Other such organic materials are carbon particles and a variety of finely divided water insoluble polymers which are often found in coating compositions in the form of latexes.
  • Illustrative of such latexes would be polystyrene, polyvinylchloride, polyacrylonitrile, synthetic rubbers, e.g., polybutadienes and the like.
  • a particlularly useful application for the suspending agents of the invention is their use in the suspension polymerization of a variety of water insoluble polymers.
  • the suspended solids that may be suspended using the polyaspartic acid salts described herein will vary between as little as 0.01 micron upto particles as large as about 1 centimeter. Typical particle sizes of this suspended solids will be in the range of 50-500 microns. In describing particle sizes it is understood that they are described with respect to the average particle size of the particular particles present in a given suspension.
  • DOSAGE The amount of water soluble salt of the poly aspartic acid used to suspend a variety of solids in water may range between 0.5-200 ppm. A typical dosage to suspend clays, iron oxides, dirt and the like is within the range of 1-50 ppm. The optimum dosage will depend upon the particular polyaspartic acid salt used, The ph of aqueous suspension and the nature of the particles with respect to their composition and size.
  • Kaolin Dispersion 1 g/L of kaolin was mixed with CaCl-,.2H 2 0. The pH of the slurry was adjusted and poured into 100 ml graduated cylinders. Known concentrations of dispersants were then added to the cylinders and thoroughly mixed.
  • the samples were also scanned with UV/VIS from 900 nm to 200 nm and the absorbance recorded at 450 nm.
  • Kaolin Dispersion with Fe 3+ This assay follows the same procedures as the kaolin dispersion test except 2.5 ppm ferric chloride are added to each graduated cylinder. The following data compares polyaspartic acid with polyacrylic acid. The results are as follows :
  • Control Polyaspartic Acid Polyacrylic Acid ppm 0 10 50 100 10 50 100 NTU (2 hours) 36 150 120 150 150 140 140 ABS (2 hours) O.ll 0.89 0.38 0.92 0.66 0.48 0.47
  • Ferric Oxide Dispersion 700 ppm Fe as Fe 2 0 3 were mixed with 200 ppm Ca 2 * as CaC0 3 .
  • the pH of the slurry was adjusted to a fixed value.
  • the solution was thoroughly mixed.
  • the slurry was transferred to 100 ml graduated cylinders and known concentrations of dispersants were added.
  • Titanium Dioxide Dispersion lg/L of titanium dioxide was mixed with 200 ppm Ca 2+ as CaC0 3 and adjusted to a fixed pH. The solution was thoroughly stirred and poured into 100 ml graduated cylinders. Known concentrations of inhibitor were added.
  • Control Polyaspartic Acid Polyacrylic Acid ppm 0. 1 10 100 1 10 100 NTU(2 hours) 282 320 412 459 331 480 594 NTU(24 hours) 21 22 36 49 23 41 44
  • Zinc Hydroxide Dispersion 250 ppm of Ca 2+ as CaC0 3 and 125 ppm Mg 2+ as CaC0 3 were made into a solution. An inhibitor was added at this time prior to the addition of O.Olg/L of zinc chloride. Equal amount of sodium hydroxide was added for each test. White precipitate of zinc hydroxide was evident. The ability of the dispersant was tested using nephelometric turbidity. The higher the NTU, the better the dispersant. Here were the results of each testing.
  • the polyaspartic acid used in all the above examples corresponds to the polyaspartic acid produced in the pilot plant test run.

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Materials Engineering (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Wood Science & Technology (AREA)
  • Health & Medical Sciences (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Molecular Biology (AREA)
  • Inorganic Chemistry (AREA)
  • Dispersion Chemistry (AREA)
  • Medicinal Chemistry (AREA)
  • Polymers & Plastics (AREA)
  • Macromolecular Compounds Obtained By Forming Nitrogen-Containing Linkages In General (AREA)

Abstract

L'invention se rapporte à des sels d'acide polyaspartique d'un poids moléculaire compris entre 1 000 et 5 000, qui constituent d'excellents agents dispersants.
PCT/US1992/001704 1991-03-06 1992-03-05 Acide polyaspartique et ses sels pour la dispersion de solides en suspension Ceased WO1992015535A1 (fr)

Applications Claiming Priority (2)

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US65510191A 1991-03-06 1991-03-06
US655,101 1991-03-06

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WO1992015535A1 true WO1992015535A1 (fr) 1992-09-17

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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5538671A (en) * 1992-10-27 1996-07-23 The Procter & Gamble Company Detergent compositions with builder system comprising aluminosilicates and polyaspartate
EP0736596A1 (fr) * 1995-04-03 1996-10-09 The Procter & Gamble Company Compositions pour trempage
FR2759611A1 (fr) * 1997-02-14 1998-08-21 Coatex Sa Nouvelle utilisation de sels d'acides polyaspartiques comme agent d'aide au broyage
US5804639A (en) * 1995-10-31 1998-09-08 Bayer Ag Pigment preparations having a high solids content
WO2000000579A1 (fr) * 1998-06-26 2000-01-06 Aware Chemicals L.L.C. Procede pour nettoyer des pieces d'une installation de laquage, servant a alimenter en peinture, notamment des conduites de peinture

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3846380A (en) * 1972-10-31 1974-11-05 M Teranishi Polyamino acid derivatives and compositions containing same
US4534881A (en) * 1983-12-19 1985-08-13 University Of South Alabama Inhibition of inorganic or biological CaCO3 deposition by poly amino acid derivatives
US4640943A (en) * 1983-09-22 1987-02-03 Ajinomoto Co., Inc. Surface modifier for inorganic substances
US4732693A (en) * 1985-07-29 1988-03-22 Lever Brothers Company Soap-nonionic detergent compositions containing a cellulose ether anti-redeposition agent
US4839461A (en) * 1986-08-07 1989-06-13 Bayer Aktiengesellschaft Polyaspartic acid from maleic acid and ammonia

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3846380A (en) * 1972-10-31 1974-11-05 M Teranishi Polyamino acid derivatives and compositions containing same
US4640943A (en) * 1983-09-22 1987-02-03 Ajinomoto Co., Inc. Surface modifier for inorganic substances
US4534881A (en) * 1983-12-19 1985-08-13 University Of South Alabama Inhibition of inorganic or biological CaCO3 deposition by poly amino acid derivatives
US4732693A (en) * 1985-07-29 1988-03-22 Lever Brothers Company Soap-nonionic detergent compositions containing a cellulose ether anti-redeposition agent
US4839461A (en) * 1986-08-07 1989-06-13 Bayer Aktiengesellschaft Polyaspartic acid from maleic acid and ammonia

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
Use of Polymers to Control Scale in Industrial Cooling Water Systems in: Chemical Aspects of Regulation of Mineralization, published 1988 (UNIVERITY OF SOUTH ALABAMA PUBLICATION SERVICES), C.S. SIKES et al., Editors. *

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5538671A (en) * 1992-10-27 1996-07-23 The Procter & Gamble Company Detergent compositions with builder system comprising aluminosilicates and polyaspartate
EP0736596A1 (fr) * 1995-04-03 1996-10-09 The Procter & Gamble Company Compositions pour trempage
US5804639A (en) * 1995-10-31 1998-09-08 Bayer Ag Pigment preparations having a high solids content
DE19540557B4 (de) * 1995-10-31 2007-03-29 Lanxess Deutschland Gmbh Pigmentpräparationen mit hohem Feststoffgehalt
FR2759611A1 (fr) * 1997-02-14 1998-08-21 Coatex Sa Nouvelle utilisation de sels d'acides polyaspartiques comme agent d'aide au broyage
EP0860477A1 (fr) * 1997-02-14 1998-08-26 Coatex S.A. Utilisation de sels d'acides polyaspartiques comme agent d'aide au broyage
US5998526A (en) * 1997-02-14 1999-12-07 Coatex S.A. Use of salts of polyaspartic acids as milling agents
WO2000000579A1 (fr) * 1998-06-26 2000-01-06 Aware Chemicals L.L.C. Procede pour nettoyer des pieces d'une installation de laquage, servant a alimenter en peinture, notamment des conduites de peinture
US6475295B1 (en) 1998-06-26 2002-11-05 Aware Chemicals L.L.C. Method for cleaning the paint feeding parts of a painting installation, especially the paint lines

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