EP0283511A1 - Pigment dispersant resin with p-containing acid - Google Patents

Pigment dispersant resin with p-containing acid

Info

Publication number
EP0283511A1
EP0283511A1 EP87906869A EP87906869A EP0283511A1 EP 0283511 A1 EP0283511 A1 EP 0283511A1 EP 87906869 A EP87906869 A EP 87906869A EP 87906869 A EP87906869 A EP 87906869A EP 0283511 A1 EP0283511 A1 EP 0283511A1
Authority
EP
European Patent Office
Prior art keywords
resin
pigment
acid
carbon atoms
esters
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.)
Withdrawn
Application number
EP87906869A
Other languages
German (de)
French (fr)
Other versions
EP0283511A4 (en
Inventor
Jozef Theresia Huybrechts
Guido Richard Louis Van Den Bosch
Rudolf Felix Landriette Verhaegen
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.)
EIDP Inc
Original Assignee
EI Du Pont de Nemours and Co
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by EI Du Pont de Nemours and Co filed Critical EI Du Pont de Nemours and Co
Publication of EP0283511A1 publication Critical patent/EP0283511A1/en
Publication of EP0283511A4 publication Critical patent/EP0283511A4/en
Withdrawn legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
    • C08F230/00—Copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and containing phosphorus, selenium, tellurium or a metal
    • C08F230/02—Copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and containing phosphorus, selenium, tellurium or a metal containing phosphorus
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
    • C08F246/00—Copolymers in which the nature of only the monomers in minority is defined
    • 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

Definitions

  • the present invention comprises a pigment dispersant. More particularly, it comprises such a dispersant having an acrylic resin containing organic acid and strong-acid phosphorus-containing monomers.
  • Sulfur-and phosphorus-containing monomers including 2-acrylamide-2-methylpropane sulfonic acid (AMPS)
  • AMPS 2-acrylamide-2-methylpropane sulfonic acid
  • acrylics and other monomers in various proportions for a variety of purposes, including for use in dispersing sediments in water.
  • an optimum dispersant resin for use in water-based coating compositions has remained an elusive desideratum.
  • U.S. Patent 4,450,013 - Hirsch et al. (1984) teaches a pigment grinding or dispersing resin of, for instance, 40-90% by weight acrylic acid, 10-60% AMPS, and 0-10% acrylonitrile, or equivalent monomers. (Parts, percentages and proportions herein are by weight except where indicated otherwise).
  • U.S. Patent 3,898,037 - Lange et al. (1975) teaches acrylamido-sulfonic acid polymers such as AMPS which may be copolymerized with other acrylics, and their use in corrosion inhibition.
  • U.S. Patent 4,177,178 - Das et al. (1979) teaches the use of A MPS copolymerized with other acrylics including long chain acrylics such as stearyl methacrylate, with a molecular weight of 15,000 to 100,000. These are said to be used to make thermosetting automotive topcoat paints.
  • European Patent Publication 129 , 329 - Farrar et al. (1984) teaches pigment dispersions using copolymers of acrylic acid with 1-50% AMPS having molecular weights in the range of 1,000 to 5,000, or up to 5700, with a low polydispersxty.
  • European Patent Publication 58,865-Perrey et al. (1982) teaches pigment dispersants with 1-10% pigment, using various acrylic sulfonic acid polymers.
  • European Patent Publication 170,474 - Backhouse (1986). teaches the use of phosphorus-containing compounds in water-based polymers to reducing gasing from metal pigments.
  • the present invention provides a pigment dispersant resin comprising copolymerized units of the following monomers in weight percent based on the polymer solids:
  • R is H or CH 3
  • R 1 is an ester, amido, alkyl, or ether linkage having 1-4 carbon atoms
  • the phosphorus-containing monomer is methacxyloxyethylphosphate (MOP).
  • the invention also includes water-based dispersions of the esin of the invention (including more or less of the resin in solution), with 50-150% of the amount of tertiary amine needed for neutralization. Pigment dispersions are also needed.
  • the preferred phosphorus-containing monomer for the invention is
  • Water based coating composition technology is based on a higher molecular weight or crosslinked latex giving rheology control with a water dispersible or soluble crosslinker such as a methylated melamine resin.
  • the amount: of inorganic acid in the dispersing resin is important for the stability of and the compatibility with the latex. With larger amounts than in this invention, one could expect real problems in film properties and compatibility, at least with certain resins. It is also k nown that reactive melamine resins are sensitive to self condensation and hydrolysis in presence of strong acids giving unstable products in the can. Too high acid values in general do give cured films which are sensitive to humidity.
  • the rest of the copolymer composition can be based on any unsaturated monomer such as acrylate, methacrylate, styrene, vinyl maleate, acrylamides or methacrylamides, or acrylonitrile or methacrylonitrile.
  • Certain preferred compositions contain MMA (methylmethacrylate) and BA (butylacrylate).
  • the copolymers should also have preferably hydroxy functionality to become an integral part of the cured polymer network.
  • HEMA hydroxyethyl methacrylate
  • HEA hydroxyethylacrylate
  • HPMA hydroxy-propylacrylate
  • HEMA hydroxypropylmethacrylate
  • HPMA hydroxybutyl acrylate
  • the copolymers are made by radical polymerization using solvents as diluents which are preferably water soluble.
  • Isopropanol (IP) is in this technology a good candidate since it forms a low boiling azeotrope with water.
  • Chain transfer agents e.g. mercaptans
  • Triganox 25C75 20.5 t-butylperoxy- pivalate from AKZO Add monomer + initiator blend over 3 hour period Triganox 25C75 : 10 IP : 40
  • Example 2 In variations on example 1, the following resin solutions were prepared.
  • Example 5 Pigment Dispersion (B) Ti-pure 902 titanium dioxide from Du Pont The same tests were run as above with following constraints:

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Health & Medical Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Medicinal Chemistry (AREA)
  • Polymers & Plastics (AREA)
  • Inorganic Chemistry (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Wood Science & Technology (AREA)
  • Paints Or Removers (AREA)
  • Pigments, Carbon Blacks, Or Wood Stains (AREA)
  • Addition Polymer Or Copolymer, Post-Treatments, Or Chemical Modifications (AREA)

Abstract

Des polymères acryliques, avec un acide carboxylique et de petites quantités d'acides forts contenant du phosphore constituent de bons agents de dispersion de pigments, à utiliser dans des compositions de revêtement aqueuses.Acrylic polymers, with a carboxylic acid and small amounts of strong phosphorus-containing acids are good pigment dispersing agents for use in aqueous coating compositions.

Description

TITLE Pigment Dispersant Resin with P-Containing Acid
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a continuation-in-part application of Serial No. 913,402 filed September 30, 1986.
Background The present invention comprises a pigment dispersant. More particularly, it comprises such a dispersant having an acrylic resin containing organic acid and strong-acid phosphorus-containing monomers.
Sulfur-and phosphorus-containing monomers, including 2-acrylamide-2-methylpropane sulfonic acid (AMPS), have been polymerized with acrylics and other monomers in various proportions for a variety of purposes, including for use in dispersing sediments in water. However, an optimum dispersant resin for use in water-based coating compositions has remained an elusive desideratum.
U.S. Patent 4,450,013 - Hirsch et al. (1984) teaches a pigment grinding or dispersing resin of, for instance, 40-90% by weight acrylic acid, 10-60% AMPS, and 0-10% acrylonitrile, or equivalent monomers. (Parts, percentages and proportions herein are by weight except where indicated otherwise).
U.S. Patent 3,711,449 - Brendley (1973) teaches interpolymers of 0.2-1.0% AMPS with other acrylates or methacrylates.
U.S. Patent 3,898,037 - Lange et al. (1975) teaches acrylamido-sulfonic acid polymers such as AMPS which may be copolymerized with other acrylics, and their use in corrosion inhibition. U.S. Patent 4,177,178 - Das et al. (1979)teaches the use of A MPS copolymerized with other acrylics including long chain acrylics such as stearyl methacrylate, with a molecular weight of 15,000 to 100,000. These are said to be used to make thermosetting automotive topcoat paints.
U.S. Patent 4,001,150 - June et al. (1977) teaches the use of phosphoric or sulfonic esters, including AMPS, copolymerized with acrylics such as methacrylic acid, for use as an electroconductive resin.
U.S. 2,914,499 - Sheetz (1959) teaches the use of various acrylic esters of sulfonic acid in emulsion polymerization.
U.S. Patent 4,008,293 - Maska et al. (1977) teaches the preparation of crosslinkable coating compositions containing, for instance, AMPS, as an internal crosslinking catalyst.
European Patent Publication 129 , 329 - Farrar et al. (1984) teaches pigment dispersions using copolymers of acrylic acid with 1-50% AMPS having molecular weights in the range of 1,000 to 5,000, or up to 5700, with a low polydispersxty.
European Patent Publication 58,865-Perrey et al. (1982) teaches pigment dispersants with 1-10% pigment, using various acrylic sulfonic acid polymers.
European Patent Publication 170,474 - Backhouse (1986). teaches the use of phosphorus-containing compounds in water-based polymers to reducing gasing from metal pigments.
Summary of the Invention
The present invention provides a pigment dispersant resin comprising copolymerized units of the following monomers in weight percent based on the polymer solids:
(a) 1.5-4% of at least one unsaturated strong-acid functional acrylic monomer having the structure
wherein R is H or CH3
R1 is an ester, amido, alkyl, or ether linkage having 1-4 carbon atoms,
(b) 1-10% of at least one organic-acid- functional acrylic monomer selected from acrylic acid, methacrylic acid, and maleic fumaric and itaconic acids and esters,
(c) 86-96% of at least one ethylenically unsaturated monomer selected from the group consisting of acrylate and methacrylate esters of alcohols having 1-12 carbon atoms, styrene, acrylonitrile, methacrylonitrile, acrylamide, methacrylamide vinyl acetate, vinyl chloride, dialkyl esters with 1-12 carbon atoms of maleic, fumaric and itaconic acids, and hydroxy-functional acrylates and meth-acrylates from alcohols or esters having 1-4 carbon atoms, said resin having a weight average molecular weight in the range of about 5,500-30,000 and an acid number in the range of about 30-120. Preferably, the phosphorus-containing monomer is methacxyloxyethylphosphate (MOP).
The invention also includes water-based dispersions of the esin of the invention (including more or less of the resin in solution), with 50-150% of the amount of tertiary amine needed for neutralization. Pigment dispersions are also needed.
Detailed Description
Evidently 1% MOP is too little in polymers of the invention to obtain desirable dispersant effects, and 5% is too much in that it causes major viscosity increases and instability in paints. Molecular weight of the polymer is important. Measured as the weight average, 4,000 is too small to obtain the advantages of the invention, 5,500 or 6,000-15,000 seems preferred, although 15,000-30,000 or 40,000 is acceptable.
The preferred phosphorus-containing monomer for the invention is
MOP (Methacryloxyethylphosphate)
Water based coating composition technology is based on a higher molecular weight or crosslinked latex giving rheology control with a water dispersible or soluble crosslinker such as a methylated melamine resin. The amount: of inorganic acid in the dispersing resin is important for the stability of and the compatibility with the latex. With larger amounts than in this invention, one could expect real problems in film properties and compatibility, at least with certain resins. It is also k nown that reactive melamine resins are sensitive to self condensation and hydrolysis in presence of strong acids giving unstable products in the can. Too high acid values in general do give cured films which are sensitive to humidity. The rest of the copolymer composition can be based on any unsaturated monomer such as acrylate, methacrylate, styrene, vinyl maleate, acrylamides or methacrylamides, or acrylonitrile or methacrylonitrile. Certain preferred compositions contain MMA (methylmethacrylate) and BA (butylacrylate). The copolymers should also have preferably hydroxy functionality to become an integral part of the cured polymer network. HEMA (hydroxyethyl methacrylate) is preferred but one could also use HEA (hydroxyethylacrylate) or less reactive HPA (hydroxy-propylacrylate) or HPMA
(hydroxypropylmethacrylate). HEMA is preferred over HEA because of its better hydrolysis resistance and over HPA, HPMA, HBA (hydroxybutyl acrylate) because it renders the copolymer more water soluble. Too low a molecular weight will not give a polymeric dispersant, resulting in poor film properties, and too high molecular weight can give compatibility problems with the other film constituents and too high viscosities with the dispersions.
The copolymers are made by radical polymerization using solvents as diluents which are preferably water soluble. Isopropanol (IP) is in this technology a good candidate since it forms a low boiling azeotrope with water. Chain transfer agents (e.g. mercaptans) can be used to control the molecular weight. Example 1 - Resin Preparation IP 1534
Heat up to reflux at 80ºC in a 4 Li flask
MMA : 751.6
BA : 1004.7
HEMA : 102.3 AA : 102.3
MOP : 41.3
IP : 302.6
Triganox 25C75 : 20.5 t-butylperoxy- pivalate from AKZO Add monomer + initiator blend over 3 hour period Triganox 25C75 : 10 IP : 40
Add and hold for 2 hours for complete conversion Test results: Solids : 51
Visc. : U (Gardner Holdt) Acid Value : 50.4
Example 2 In variations on example 1, the following resin solutions were prepared.
MMA BA HEMA AA MOP
Example 1 37.5 50.4 5.1 5.1 2.1
Example 2 40 37 16 5 2
Test results:
Solids-% MN MW D AN VISC
1 51 3600 9500 2.7 50. 4 U
2 57.3 3200 7560 2.4 48. 3 YAll resin solutions were neutralized with AMP (aminomethylpropanol) to pH 8.4 - 8.7 and diluted to 50% solids with deionized water (where relevant). Example 4 -Pigment Dispersion (A) Sicotrans L 2817 transparent iron oxide red from BASF
Following blends made with a Cowless mixer blade and afterwards ground in suitable equipment such as Dynomill, ball mill, etc.
Constraints:
10% < Sicotrans L 2817 < 30% 15% A Neutralized resin solution <80% 50% solids 10% < Deionized water/Propyleneglycol < 75% blend All dispersions were tested for gloss, transparency, rheology. Example 2 gave the best results. Example 5 - Pigment Dispersion (B) Ti-pure 902 titanium dioxide from Du Pont The same tests were run as above with following constraints:
40 < TiO2 < 85%
10 < Neutralized resin solution < 55% 5 < Deionized water < 50% Resin examples 1 and 2 gave excellent results,

Claims

Claims
1. A pigment-dispersant resin comprising copolymerized units of the following monomers in weight percent based on the polymer solids:
(a) 1.5-4% of at least one unsaturated strong-acid functional acrylic monomer having the structure
wherein R is H or CH3
R1 is an ester, amido, alkyl, or ether linkage having 1-4 carbon atoms,
(b) 1-10% of at least one organic-acid- functional acrylic monomer selected from acrylic acid, methacrylic acid, and maleic, fumaric and itaconic acids and esters,
(c) 86-9.6% of at least one ethylenically unsaturated monomer selected from the group consisting of acrylate and methacrylate esters of alcohols having 1-12 carbon atoms, stryene, acrylonitrile, methacrylonitrile, acrylamide, methacrylamide, vinyl- aoetate, vinyl chloride, dialkyl esters with 1-12 carbon atoms of maleic, fumaric and itaconic acids, and hydroxy-functional acrylates and methacrylates from alcohols or esters having 1-4 carbon atoms, said resin having a weight average molecular weight in the range of about 5,500-30,000 and an acid number in the range of about 30-120.
2. The resin of claim 1 wherein
(a) is methacryloxyethyl phosphate.
3. The resin of claim 1 wherein
(b) is acrylic acid.
4. The resin of claim 1 wherein (b) is methacrylic acid.
5. The resin of claim 1 wherein
(c) is hydroxyethyl methacrylate
6. The resin of cliam 1 wherein
(b) is methyl methacrylate and butyl acrylate and
(c) is hydroxyethyl methacrylate
7. The resin of claim 8 having a weight average molecular weight in the range of 6,000-15,000.
8. An aqueous dispersion of the resin of claim 7 containing tertiary amine in an amount from 50% to 150% of the amount needed for stoichiometric neutralization of said resin.
9. A pigment dispersion comprising the dispersion of claim 8 and a pigment.
10. The pigment dispersion of claim 9 wherein the pigment comprises TiO2.
11. The pigment dispersion of claim 9 wherein the pigment comprises aluminum flake.
12. The pigment dispersion of claim 9 wherein the pigment comprises iron oxide.
EP19870906869 1986-09-30 1987-09-25 Pigment dispersant resin with p-containing acid. Withdrawn EP0283511A4 (en)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
US91340286A 1986-09-30 1986-09-30
US913402 1986-09-30
US93425486A 1986-11-24 1986-11-24
US934254 1986-11-24

Publications (2)

Publication Number Publication Date
EP0283511A1 true EP0283511A1 (en) 1988-09-28
EP0283511A4 EP0283511A4 (en) 1989-01-26

Family

ID=27129623

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19870906869 Withdrawn EP0283511A4 (en) 1986-09-30 1987-09-25 Pigment dispersant resin with p-containing acid.

Country Status (2)

Country Link
EP (1) EP0283511A4 (en)
WO (1) WO1988002382A1 (en)

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB8811850D0 (en) * 1988-05-19 1988-06-22 Int Paint Plc Marine paint
FR2637511B1 (en) * 1988-10-10 1994-02-11 Coatex Sa COMPATIBILITY AGENT FOR POLYPIGMENTAL AQUEOUS SUSPENSIONS, ONE OF THE PIGMENTS OF WHICH IS HYDRATED CALCIUM SULPHATE
GB8909733D0 (en) * 1989-04-27 1989-06-14 Ici Plc Dispersions
FR2650594B1 (en) * 1989-08-04 1992-04-03 Coatex Sa APPLICATION TO AQUEOUS PIGMENTARY SUSPENSIONS OF CALCIUM CARBONATE OF A POLYCARBOXYLIC AGENT WITH PHOSPHATE OR PHOSPHONE FUNCTION INHIBITING THE EFFECT OF SHOCK CAUSED BY THE INTRODUCTION OF AN ELECTROLYTE IN CONCENTRATED FORM
GB9418985D0 (en) * 1994-09-21 1994-11-09 Albright & Wilson Dispersion of solid particles in water
JP2001240791A (en) 2000-02-25 2001-09-04 Nippon Paint Co Ltd Method for forming composite coating film
FR2867478B1 (en) * 2004-03-10 2006-04-28 Cray Valley Sa AQUEOUS POLYMER DISPERSION FOR BARRIER COATING

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3524197A1 (en) * 1984-07-06 1986-01-16 Toyo Soda Manufacturing Co., Ltd., Shinnanyo, Yamaguchi COLORED POLYMER EMULSION AND METHOD FOR THEIR PRODUCTION

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4001150A (en) * 1970-11-25 1977-01-04 Kansai Paint Company, Ltd. Composition for preparing electroconductive resin comprising an unsaturated polyester and phosphoric or sulfonic unsaturated ester
US4539382A (en) * 1981-07-29 1985-09-03 Kuraray Co., Ltd. Adhesive composition
PL143722B1 (en) * 1984-01-17 1988-03-31 Ici Plc Milk weighing balance

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3524197A1 (en) * 1984-07-06 1986-01-16 Toyo Soda Manufacturing Co., Ltd., Shinnanyo, Yamaguchi COLORED POLYMER EMULSION AND METHOD FOR THEIR PRODUCTION

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See also references of WO8802382A1 *

Also Published As

Publication number Publication date
EP0283511A4 (en) 1989-01-26
WO1988002382A1 (en) 1988-04-07

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