High-molecular polymer dispersing agent as well as preparation method and application thereof

Abstract

The invention provides a high-molecular polymer dispersing agent as well as a preparation method and application thereof. The high-molecular polymer dispersing agent is prepared from the following raw materials: a first monomer, a second monomer, a third monomer, an initiator and a modifier, the first monomer is prepared from an enamine monomer and a phenyl aldehyde monomer through a condensation reaction; the second monomer comprises an anhydride compound; and the third monomer comprises allyl polyoxyethylene methyl terminated polyether. The preparation raw materials of the high-molecular polymer dispersant provided by the invention comprise specific types of monomers and modifiers, and the prepared high-molecular polymer dispersant can be used for dispersing commercially available conventional organic pigments and can be used for preparing water-based color paste with good storage stability, low viscosity and low particle size.

Description

Technical Field

[0001] The invention belongs to the technical field of dispersants and relates to a high molecular polymer dispersant and a preparation method and application thereof. Background Art

[0002] Organic pigments need to go through three dispersion processes: wetting, dispersion, and stabilization, to form a highly dispersed state before being added to the substrate to color it. They are widely used in the fields of inks, paints, and coatings.

[0003] The dispersion process of organic pigments is that the fine pigment particles formed by mechanical crushing form a uniform suspension with the paint. Under the adsorption effect of the dispersant, they are wrapped on the surface of the fine pigment particles to form an adsorption layer, which produces charge repulsion and air steric effect, preventing the dispersed pigment particles from forming harmful flocculation again and maintaining the system in a stable suspension state. Traditional organic pigments are usually dispersed with low molecular weight surface treatment agents, such as alkylphenol polyoxyethylene, fatty alcohol polyoxyethylene ether, etc., which are used in large quantities and have weak adsorption capacity. They are easy to detach from the surface of pigment particles, resulting in large particle size of the dispersed slurry and unstable dispersion effect. Therefore, traditional dispersants are not effective in applications that require high stability and durability, and their scope of application is relatively narrow.

[0004] High molecular weight polymer dispersants usually have a large molecular weight and a complex molecular structure. They are adsorbed on the surface of pigment particles through anchoring groups to form a stable adsorption layer that is difficult to desorb. This irreversible adsorption ability makes high molecular weight dispersants show stronger stability and durability in pigment dispersion. High molecular weight polymer dispersants have a long solvation chain and can form an effective steric hindrance around the pigment particles to prevent aggregation and flocculation between particles. This steric stabilization effect makes the dispersion system more uniform and stable.

[0005] However, there are still few types of existing high molecular weight polymer dispersants. Therefore, a new type of high molecular weight polymer dispersant is developed in the art. Summary of the invention

[0006] In view of the shortcomings of the prior art, the object of the present invention is to provide a polymer dispersant and a preparation method and application thereof. The polymer dispersant provided by the present invention can be used for dispersing conventional commercially available organic pigments, and can prepare water-based color pastes with good storage stability, low viscosity and low particle size, and has broad application prospects in the field of dispersing organic pigments.

[0007] To achieve this object, the present invention adopts the following technical solutions:

[0008] In a first aspect, the present invention provides a high molecular weight polymer dispersant, wherein the raw materials for preparing the high molecular weight polymer dispersant include a first monomer, a second monomer, a third monomer, an initiator and a modifier;

[0009] The first monomer is prepared by condensation reaction of an enamine monomer and a phenylaldehyde monomer;

[0010] The second monomer includes an anhydride compound;

[0011] The third monomer includes allyl polyoxyethylene methyl terminated polyether.

[0012] The raw materials for preparing the high molecular polymer dispersant provided by the present invention include specific types of monomers and modifiers. The prepared high molecular polymer dispersant can be used for dispersing commercially available conventional organic pigments and can prepare water-based color pastes with good storage stability, low viscosity and low particle size.

[0013] Preferably, the enamine monomer includes any one of 3-butene-1-amine, 2-methylallylamine, allylamine, 3-methyl-2-butene-1-amine, and pent-4-ene-1-amine, or a combination of at least two thereof.

[0014] Preferably, the phenyl aldehyde monomer includes any one of benzaldehyde, phenylacetaldehyde, p-methylbenzaldehyde, 2-methylbenzaldehyde, 3-methylbenzaldehyde, pentamethylbenzaldehyde, 2,3-dimethylbenzaldehyde, 2,4-dimethylbenzaldehyde, 2,5-dimethylbenzaldehyde, 2,6-dimethylbenzaldehyde, 3,4-dimethylbenzaldehyde, 3,5-dimethylbenzaldehyde, 2-phenylpropanaldehyde, and 2-methylphenylacetaldehyde, or a combination of at least two thereof.

[0015] Preferably, the molar ratio of the enamine monomer to the phenylaldehyde monomer is (4-10):1, for example, 4:1, 4.5:1, 5:1, 5.5:1, 6:1, 6.5:1, 7:1, 7.5:1, 8:1, 8.5:1, 9:1, 9.5:1, 10:1, etc.

[0016] Preferably, the first monomer is prepared by the following method:

[0017] The enamine monomer and the phenylaldehyde monomer are dissolved in a solvent, reacted at a temperature of 400 °C, and post-treated to obtain the first monomer.

[0018] Preferably, the solvent includes any one of methanol, ethanol, isopropanol, and n-propanol, or a combination of at least two of them.

[0019] Preferably, the amount of the solvent added is 2 to 10 times the sum of the mass of the enamine monomer and the phenylaldehyde monomer, for example, 2 times, 3 times, 4 times, 5 times, 6 times, 7 times, 8 times, 9 times, 10 times, etc.

[0020] Preferably, the temperature of the insulation reaction is 20-50°C, for example 20°C, 25°C, 30°C, 35°C, 40°C, 45°C, 50°C, etc., and the time of the insulation reaction is 0.2-5 hours, for example 0.2 hours, 0.5 hours, 1 hour, 1.5 hours, 2 hours, 2.5 hours, 3 hours, 3.5 hours, 4 hours, 4.5 hours, 5 hours, etc.

[0021] Preferably, the post-treatment comprises distillation under reduced pressure to remove the solvent and unreacted enamine monomers.

[0022] Preferably, the second monomer includes any one of maleic anhydride, itaconic anhydride, and citraconic anhydride, or a combination of at least two of them.

[0023] Preferably, the allyl polyoxyethylene methyl terminated polyether has the following general formula: CH2=CHCH2O(CH2CH2O) n CH3, wherein n is an integer from 5 to 20, for example, 5, 6, 8, 10, 12, 14, 16, 18, 20, etc.

[0024] Preferably, the weight average molecular weight (M w ) is 350-500 g / mol, such as 350 g / mol, 400 g / mol, 450 g / mol, 500 g / mol, etc. Preferably, the initiator comprises an azo initiator.

[0025] Preferably, the azo initiator includes any one of azobisisobutyronitrile, azobisisoheptanenitrile, azobisisovaleronitrile, and dimethyl azobisisobutyrate, or a combination of at least two thereof.

[0026] Preferably, the modifier includes any one of phenylhydrazine, benzylhydrazine, 1-methyl-1-phenylhydrazine, phenelzine, 1-ethyl-1-phenylhydrazine, (2,4,6-trimethylbenzyl)hydrazine, or a combination of at least two thereof.

[0027] Preferably, the molar ratio of the first monomer to the second monomer is (1-2):(2-3), for example, 1:1, 1:1.5, 1:2, 1:3, etc.

[0028] Preferably, the molar ratio of the second monomer to the third monomer is (2-3):(2-6), for example, 1:1, 1:2, 1:3, 1.5:1, etc.

[0029] Preferably, the amount of the initiator is 2% to 10% of the sum of the mass of the first monomer, the second monomer and the third monomer, for example, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, etc.

[0030] Preferably, the molar ratio of the modifier to the second monomer is (0.8-1.2):1, for example, 0.8:1, 0.9:1, 1:1, 1.1:1, 1.2:1, etc.

[0031] In a second aspect, the present invention provides a method for preparing the polymer dispersant as described in the first aspect, the preparation method comprising the following steps:

[0032] (1) mixing a first monomer, a second monomer and a portion of a third monomer, and then adding an organic solvent to obtain a first mixed solution;

[0033] (2) mixing an initiator and an organic solvent to obtain a second mixed solution;

[0034] (3) raising the temperature of the remaining third monomer, then adding the first mixed solution and the second mixed solution, and keeping the temperature to react to obtain an intermediate;

[0035] (4) heating the system of step (3), then adding a modifier, and keeping the temperature to react to obtain the high molecular weight polymer dispersant.

[0036] Preferably, the amount of the part of the third monomer in step (1) is 40wt.% to 60wt.% of the total amount of the third monomer, for example, 40wt.%, 42wt.%, 44wt.%, 46wt.%, 48wt.%, 50wt.%, 52wt.%, 54wt.%, 56wt.%, 58wt.%, 60wt.%, etc.

[0037] Preferably, the organic solvents in step (1) and step (2) each independently include any one of ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, or a combination of at least two of them.

[0038] Preferably, the amount of the organic solvent added in step (1) is 1 to 1.2 times the sum of the mass of the first monomer, the second monomer, and part of the third monomer, for example, 1 time, 1.1 times, 1.2 times, etc.

[0039] Preferably, the amount of the organic solvent added in step (2) is 5 to 10 times the mass of the initiator, for example, 5 times, 6 times, 7 times, 8 times, 9 times, 10 times, etc.

[0040] Preferably, the heating in step (3) is to 60-100°C, for example, 60°C, 65°C, 70°C, 75°C, 80°C, 85°C, 90°C, 95°C, 100°C, etc.

[0041] Preferably, in step (3), the first mixed liquid and the second mixed liquid are added under stirring.

[0042] Preferably, the adding of the first mixed solution and the second mixed solution in step (3) is specifically: controlling the first mixed solution and the second mixed solution to be added dropwise within 1 to 5 hours (eg, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours, etc.).

[0043] Preferably, the insulation reaction time of step (3) is 0.5 to 5 hours, for example, 0.5 hours, 1 hour, 1.5 hours, 2 hours, 2.5 hours, 3 hours, 3.5 hours, 4 hours, 4.5 hours, 5 hours, etc.

[0044] Preferably, the heating in step (4) is to 120-160°C, for example, 120°C, 125°C, 130°C, 135°C, 140°C, 145°C, 150°C, 155°C, 160°C, etc.

[0045] Preferably, the insulation reaction time in step (4) is 2 to 10 hours, for example, 2 hours, 3 hours, 4 hours, 5 hours, 6 hours, 7 hours, 8 hours, 9 hours, 10 hours, etc.

[0046] Preferably, the insulation reaction in step (4) is terminated when the acid value is less than 2 mgKOH / g.

[0047] Preferably, the weight average molecular weight of the high molecular weight polymer dispersant is 5000-100000 g / mol, for example 5000 g / mol, 6000 g / mol, 8000 g / mol, 10000 g / mol, 20000 g / mol, 30000 g / mol, 40000 g / mol, 50000 g / mol, 60000 g / mol, 70000 g / mol, 80000 g / mol, 90000 g / mol, 100000 g / mol, etc.

[0048] In the present invention, the weight average molecular weight of the high molecular weight polymer dispersant is measured by gel permeation chromatography (GPC) using polyethylene oxide as a calibration standard and a water / acetonitrile mixed solution as an eluent.

[0049] In a third aspect, the present invention provides a use of the high molecular weight polymer dispersant as described in the first aspect in dispersing an organic pigment.

[0050] Compared with the prior art, the present invention has at least the following beneficial effects:

[0051] The raw materials for preparing the high molecular polymer dispersant provided by the present invention include specific types of monomers and modifiers. The prepared high molecular polymer dispersant can be used for dispersing commercially available conventional organic pigments and can prepare water-based color pastes with good storage stability, low viscosity and low particle size. DETAILED DESCRIPTION

[0052] The technical solution of the present invention is further described below by specific implementation methods. It should be understood by those skilled in the art that the embodiments are only to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0053] Preparation Example 1

[0054] In this preparation example, a first monomer is provided, and the preparation method comprises the following steps:

[0055] Dissolving an enamine monomer and a phenyl aldehyde monomer in a molar ratio of 4:1 in a solvent, reacting at 30° C. for 2 hours, and distilling under reduced pressure to remove the solvent and unreacted enamine monomer to obtain the first monomer;

[0056] The enamine monomer is 3-butene-1-amine, the phenylaldehyde monomer is benzaldehyde, the solvent is ethanol, and the amount of the solvent added is 2.5 times the sum of the masses of the enamine monomer and the phenylaldehyde monomer.

[0057] Preparation Example 2

[0058] In this preparation example, a first monomer is provided, and the preparation method comprises the following steps:

[0059] Dissolving an enamine monomer and a phenyl aldehyde monomer in a molar ratio of 8:1 in a solvent, reacting at 20° C. for 4 hours, and distilling under reduced pressure to remove the solvent and unreacted enamine monomer to obtain the first monomer;

[0060] The enamine monomer is allylamine, the phenyl aldehyde monomer is p-methylbenzaldehyde, the solvent is isopropanol, and the added amount of the solvent is 7 times the sum of the masses of the enamine monomer and the phenyl aldehyde monomer.

[0061] Preparation Example 3

[0062] In this preparation example, a first monomer is provided, and the preparation method comprises the following steps:

[0063] Dissolving an enamine monomer and a phenyl aldehyde monomer in a molar ratio of 10:1 in a solvent, reacting at 50° C. for 0.8 hours, and distilling under reduced pressure to remove the solvent and unreacted enamine monomer to obtain the first monomer;

[0064] The enamine monomer is 2-methylallylamine, the phenylaldehyde monomer is phenylacetaldehyde, the solvent is methanol, and the amount of the solvent added is 10 times the sum of the masses of the enamine monomer and the phenylaldehyde monomer.

[0065] Example 1

[0066] In this embodiment, a high molecular weight polymer dispersant is provided, and the preparation method comprises the following steps:

[0067] (1) uniformly mixing the first monomer, the second monomer and 50% by weight of the third monomer, and then adding an organic solvent in an amount equal to the mass of the three monomers to obtain a first mixed solution;

[0068] (2) dissolving the initiator in an organic solvent in an amount of 6 times the mass of the initiator to obtain a second mixed solution;

[0069] (3) adding the remaining third monomer into a reaction flask with stirring, temperature control and condensation, heating to 70° C., and then dropping the first mixed solution and the second mixed solution into the flask simultaneously within 1 hour under stirring. After the dropping is completed, the temperature is kept at 0.5 hours to obtain an intermediate;

[0070] (4) heating the system of step (3) to 120° C., then adding a modifier for modification, and keeping the temperature for reaction for 2 hours. The reaction is judged to be complete when the acid value is less than 2 mgKOH / g, thereby obtaining the high molecular weight polymer dispersant (weight average molecular weight: 98543 g / mol);

[0071] The first monomer is provided by Preparation Example 1, the second monomer is maleic anhydride, and the third monomer is allyl polyoxyethylene methyl terminated polyether (M w =350g / mol), the initiator is azobisisobutyronitrile, the modifier is benzylhydrazine, the molar ratio of the first monomer, the second monomer, and the third monomer is 1:2:2, the amount of the initiator is 2% of the sum of the mass of the first monomer, the second monomer, and the third monomer, and the molar ratio of the modifier to the second monomer is 1:1;

[0072] The organic solvents in step (1) and step (2) are both diethylene glycol dimethyl ether.

[0073] Example 2

[0074] In this embodiment, a high molecular weight polymer dispersant is provided, and the preparation method comprises the following steps:

[0075] (1) uniformly mixing the first monomer, the second monomer and 50% by weight of the third monomer, and then adding an organic solvent in an amount equal to the mass of the three monomers to obtain a first mixed solution;

[0076] (2) dissolving the initiator in an organic solvent in an amount 5 times the mass of the initiator to obtain a second mixed solution;

[0077] (3) adding the remaining third monomer into a reaction flask with stirring, temperature control and condensation, heating to 60° C., and then dropping the first mixed solution and the second mixed solution into the flask simultaneously within 3 hours under stirring. After the dropping is completed, the temperature is kept for 1 hour to obtain an intermediate;

[0078] (4) heating the system of step (3) to 160° C., then adding a modifier for modification, and keeping the temperature for reaction for 6 hours. The reaction is judged to be complete when the acid value is less than 2 mgKOH / g, thereby obtaining the high molecular weight polymer dispersant (weight average molecular weight: 33583 g / mol);

[0079] The first monomer is provided by Preparation Example 2, the second monomer is itaconic anhydride, and the third monomer is allyl polyoxyethylene methyl terminated polyether (M w =500g / mol), the initiator is azobisisoheptanenitrile, the modifier is phenylhydrazine, the molar ratio of the first monomer, the second monomer, and the third monomer is 1:3:6, the amount of the initiator is 6% of the sum of the mass of the first monomer, the second monomer, and the third monomer, and the molar ratio of the modifier to the second monomer is 0.8:1;

[0080] The organic solvents in step (1) and step (2) are both diethylene glycol dimethyl ether.

[0081] Example 3

[0082] In this embodiment, a high molecular weight polymer dispersant is provided, and the preparation method comprises the following steps:

[0083] (1) uniformly mixing the first monomer, the second monomer and 50% by weight of the third monomer, and then adding an organic solvent in an amount equal to the mass of the three monomers to obtain a first mixed solution;

[0084] (2) dissolving the initiator in an organic solvent having an amount 10 times the mass of the initiator to obtain a second mixed solution;

[0085] (3) adding the remaining third monomer into a reaction flask with stirring, temperature control and condensation, heating to 95° C., and then dropping the first mixed solution and the second mixed solution into the flask simultaneously within 2 hours under stirring. After the dropping is completed, the temperature is kept for 3 hours to obtain an intermediate;

[0086] (4) heating the system of step (3) to 135° C., then adding a modifier for modification, and keeping the temperature for reaction for 5 hours. The reaction is judged to be complete when the acid value is less than 2 mgKOH / g, thereby obtaining the high molecular weight polymer dispersant (weight average molecular weight: 7693 g / mol);

[0087] The first monomer is provided by Preparation Example 3, the second monomer is citraconic anhydride, and the third monomer is allyl polyoxyethylene methyl terminated polyether (M w =500g / mol), the initiator is dimethyl azobisisobutyrate, the modifier is phenelhydrazine, the molar ratio of the first monomer, the second monomer, and the third monomer is 2:2:5, the amount of the initiator is 10% of the sum of the mass of the first monomer, the second monomer, and the third monomer, and the molar ratio of the modifier to the second monomer is 0.9:1;

[0088] The organic solvents in step (1) and step (2) are both triethylene glycol dimethyl ether.

[0089] Example 4

[0090] In this embodiment, a high molecular weight polymer dispersant is provided, and the preparation method comprises the following steps:

[0091] (1) uniformly mixing the first monomer, the second monomer and 50% by weight of the third monomer, and then adding an organic solvent in an amount equal to the mass of the three monomers to obtain a first mixed solution;

[0092] (2) dissolving the initiator in an organic solvent in an amount of 8 times the mass of the initiator to obtain a second mixed solution;

[0093] (3) adding the remaining third monomer into a reaction flask with stirring, temperature control and condensation, heating to 85° C., and then dropping the first mixed solution and the second mixed solution into the flask simultaneously within 4 hours under stirring. After the dropping is completed, the temperature is kept for 5 hours to obtain an intermediate;

[0094] (4) heating the system of step (3) to 145° C., then adding a modifier for modification, and keeping the temperature for reaction for 10 hours. The reaction is judged to be complete when the acid value is less than 2 mgKOH / g, thereby obtaining the high molecular weight polymer dispersant (weight average molecular weight: 42185 g / mol);

[0095] The first monomer is provided by Preparation Example 1, the second monomer is citraconic anhydride, and the third monomer is allyl polyoxyethylene methyl terminated polyether (M w =500g / mol), the initiator is azobisisoheptylnitrile, the modifier is 1-methyl-1-phenylhydrazine, the molar ratio of the first monomer, the second monomer, and the third monomer is 2:2.5:5, the amount of the initiator is 5% of the sum of the mass of the first monomer, the second monomer, and the third monomer, and the molar ratio of the modifier to the second monomer is 1.1:1;

[0096] The organic solvents in step (1) and step (2) are both ethylene glycol dimethyl ether.

[0097] Example 5

[0098] In this embodiment, a high molecular weight polymer dispersant is provided, and the preparation method comprises the following steps:

[0099] (1) uniformly mixing the first monomer, the second monomer and 50% by weight of the third monomer, and then adding an organic solvent in an amount equal to the mass of the three monomers to obtain a first mixed solution;

[0100] (2) dissolving the initiator in an organic solvent in an amount of 9 times the mass of the initiator to obtain a second mixed solution;

[0101] (3) adding the remaining third monomer into a reaction flask with stirring, temperature control and condensation, heating to 80° C., and then dropping the first mixed solution and the second mixed solution into the flask simultaneously within 5 hours under stirring. After the dropping is completed, the temperature is kept for 4 hours to obtain an intermediate;

[0102] (4) heating the system of step (3) to 155° C., then adding a modifier for modification, and keeping the temperature for reaction for 8 hours. The reaction is judged to be complete when the acid value is less than 2 mgKOH / g, thereby obtaining the high molecular weight polymer dispersant (the polymer weight average molecular weight is: 56352 g / mol);

[0103] The first monomer is provided by Preparation Example 2, the second monomer is maleic anhydride, and the third monomer is allyl polyoxyethylene methyl terminated polyether (M w =500g / mol), the initiator is azobisisovaleronitrile, the modifier is (2,4,6-trimethylbenzyl)hydrazine, the molar ratio of the first monomer, the second monomer, and the third monomer is 1:2.5:4.5, the amount of the initiator is 4% of the sum of the mass of the first monomer, the second monomer, and the third monomer, and the molar ratio of the modifier to the second monomer is 1.2:1;

[0104] The organic solvents in step (1) and step (2) are both ethylene glycol dimethyl ether.

[0105] Example 6

[0106] In this embodiment, a high molecular weight polymer dispersant is provided, and the preparation method comprises the following steps:

[0107] (1) uniformly mixing the first monomer, the second monomer and 50% by weight of the third monomer, and then adding an organic solvent in an amount equal to the mass of the three monomers to obtain a first mixed solution;

[0108] (2) dissolving the initiator in an organic solvent in an amount 7 times the mass of the initiator to obtain a second mixed solution;

[0109] (3) adding the remaining third monomer into a reaction flask that is stirred, temperature-controlled, and condensed, and heating to 100° C., and then dripping the first mixed solution and the second mixed solution into the flask simultaneously over 3.5 hours under stirring, and keeping the temperature for 2 hours after the dripping is completed, to obtain an intermediate;

[0110] (4) heating the system of step (3) to 150° C., then adding a modifier for modification, and keeping the temperature for reaction for 4 hours. The reaction is judged to be complete when the acid value is less than 2 mgKOH / g, thereby obtaining the high molecular weight polymer dispersant (the polymer weight average molecular weight is: 21394 g / mol);

[0111] The first monomer is provided by Preparation Example 3, the second monomer is itaconic anhydride, and the third monomer is allyl polyoxyethylene methyl terminated polyether (M w =350g / mol), the initiator is dimethyl azobisisobutyrate, the modifier is phenylhydrazine, the molar ratio of the first monomer, the second monomer, and the third monomer is 1.5:2:2, the amount of the initiator is 7% of the sum of the mass of the first monomer, the second monomer, and the third monomer, and the molar ratio of the modifier to the second monomer is 1:1;

[0112] The organic solvents in step (1) and step (2) are both triethylene glycol dimethyl ether.

[0113] Comparative Example 1

[0114] The only difference between this comparative example and Example 1 is that the second monomer maleic anhydride is not included in the preparation raw materials.

[0115] Comparative Example 2

[0116] The only difference between this comparative example and Example 1 is that the first monomer provided by Preparation Example 1 is not included in the preparation raw materials.

[0117] Comparative Example 3

[0118] The only difference between this comparative example and Example 1 is that the modifier benzylhydrazine is replaced by an equimolar amount of benzylamine.

[0119] Comparative Example 4

[0120] The only difference between this comparative example and Example 1 is that the third monomer allyl polyoxyethylene methyl terminated polyether (M w =350 g / mol).

[0121] Test Case

[0122] By laboratory sand grinding, according to the total amount of slurry formula of 100g, high molecular polymer dispersant, water, pH adjuster ammonia water, organic pigment (phthalocyanine blue 15:3) were added in sequence according to the proportion; after stirring evenly, 200g of zirconium beads with a particle size of 1.2-1.4mm were added and sealed in a glass jar, shaken for 8 hours, and filtered to obtain the color paste.

[0123] The specific formula of the color paste prepared by the present invention is shown in Table 1:

[0124] Table 1

[0125]

[0126] Performance Testing

[0127] (1) Viscosity: measured using NDJ-1B rotational viscometer, Shanghai Changji Geological Instrument Co., Ltd.; “-” indicates that the viscosity is too high to be measured;

[0128] (2) Particle size: tested using BT-90 laser particle size analyzer, Dandong Better Instrument Co., Ltd.; “\” represents precipitation or no fluidity and cannot be tested;

[0129] (3) Storage stability: Store at 55°C for 7 days, observe the color paste state, and re-measure the particle size and viscosity.

[0130] The specific test results are shown in Table 2:

[0131] Table 2

[0132]

[0133] It can be seen from Table 2 that the high molecular weight polymer dispersant provided in the embodiment of the present invention can be used for dispersing commercially available conventional organic pigments, and can prepare an aqueous color paste with good storage stability (stored at 55°C for 7 days, the viscosity and particle size of the color paste change little), low viscosity (initial viscosity: 115-175mpa·s), and small particle size (initial particle size: 215-287nm).

[0134] From the comparison between Comparative Test Examples 1-4 and Test Example 1, it can be seen that when the high molecular weight polymer dispersant provided in Comparative Examples 1-4 is used to disperse the organic pigment, the stability of the color paste is significantly deteriorated, and the viscosity and particle size of the color paste are both larger.

[0135] From the comparison between comparative test example 5 and test example 1, it can be seen that compared with the blank sample, the polymer dispersant provided in Example 1 has a good dispersing effect on the slurry viscosity and particle size, which proves that the polymer dispersant provided by the present invention has a good application effect on the color paste.

[0136] The applicant declares that the present invention illustrates the polymer dispersant and its preparation method and application through the above-mentioned embodiments, but the present invention is not limited to the above-mentioned embodiments, that is, it does not mean that the present invention must rely on the above-mentioned embodiments to be implemented. Those skilled in the art should understand that any improvement of the present invention, equivalent replacement of various raw materials of the product of the present invention, addition of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

Claims

1. A high molecular weight polymer dispersant, characterized in that: The raw materials for preparing the high molecular polymer dispersant include a first monomer, a second monomer, a third monomer, an initiator and a modifier; The first monomer is prepared by condensation reaction of an enamine monomer and a phenylaldehyde monomer; The second monomer includes an anhydride compound; The third monomer includes allyl polyoxyethylene methyl terminated polyether.

2. The high molecular weight polymer dispersant according to claim 1, characterized in that The enamine monomers include any one of 3-butene-1-amine, 2-methylallylamine, allylamine, 3-methyl-2-butene-1-amine, and pent-4-ene-1-amine, or a combination of at least two thereof; Preferably, the phenylaldehyde monomer includes any one of benzaldehyde, phenylacetaldehyde, p-methylbenzaldehyde, 2-methylbenzaldehyde, 3-methylbenzaldehyde, pentamethylbenzaldehyde, 2,3-dimethylbenzaldehyde, 2,4-dimethylbenzaldehyde, 2,5-dimethylbenzaldehyde, 2,6-dimethylbenzaldehyde, 3,4-dimethylbenzaldehyde, 3,5-dimethylbenzaldehyde, 2-phenylpropanaldehyde, and 2-methylphenylacetaldehyde, or a combination of at least two thereof; Preferably, the molar ratio of the enamine monomer to the phenylaldehyde monomer is (4-10):

1.

3. The high molecular weight polymer dispersant according to claim 1 or 2, characterized in that: The first monomer is prepared by the following method: dissolving an enamine monomer and a phenylaldehyde monomer in a solvent, reacting at a temperature of 100 °C, and performing post-treatment to obtain the first monomer; Preferably, the solvent includes any one of methanol, ethanol, isopropanol, and n-propanol, or a combination of at least two thereof; Preferably, the amount of the solvent added is 2 to 10 times the sum of the mass of the enamine monomer and the phenylaldehyde monomer; Preferably, the temperature of the insulation reaction is 20 to 50° C., and the insulation reaction time is 0.2 to 5 hours; Preferably, the post-treatment comprises distillation under reduced pressure.

4. The high molecular weight polymer dispersant according to any one of claims 1 to 3, characterized in that: The second monomer includes any one of maleic anhydride, itaconic anhydride, and citraconic anhydride, or a combination of at least two thereof; Preferably, the allyl polyoxyethylene methyl terminated polyether has the following general formula: CH2=CHCH2O(CH2CH2O) n CH3, wherein n is an integer from 5 to 20; Preferably, the weight average molecular weight of the allyl polyoxyethylene methyl terminated polyether is 350 to 500 g / mol; Preferably, the initiator comprises an azo initiator; Preferably, the azo initiator includes any one of azobisisobutyronitrile, azobisisoheptanenitrile, azobisisovaleronitrile, and dimethyl azobisisobutyrate, or a combination of at least two thereof; Preferably, the modifier includes any one of phenylhydrazine, benzylhydrazine, 1-methyl-1-phenylhydrazine, phenelzine, 1-ethyl-1-phenylhydrazine, (2,4,6-trimethylbenzyl)hydrazine, or a combination of at least two thereof.

5. The high molecular weight polymer dispersant according to any one of claims 1 to 4, characterized in that: The molar ratio of the first monomer to the second monomer is (1-2):(2-3); Preferably, the molar ratio of the second monomer to the third monomer is (2-3):(2-6); Preferably, the amount of the initiator is 2% to 10% of the sum of the mass of the first monomer, the second monomer, and the third monomer; Preferably, the molar ratio of the modifier to the second monomer is (0.8-1.2):

1.

6. A method for preparing a high molecular weight polymer dispersant as claimed in any one of claims 1 to 5, characterized in that: The preparation method comprises the following steps: (1) mixing a first monomer, a second monomer and a portion of a third monomer, and then adding an organic solvent to obtain a first mixed solution; (2) mixing an initiator and an organic solvent to obtain a second mixed solution; (3) raising the temperature of the remaining third monomer, then adding the first mixed solution and the second mixed solution, and keeping the temperature to react to obtain an intermediate; (4) heating the system of step (3), then adding a modifier, and reacting at the same temperature to obtain the high molecular weight polymer dispersant.

7. The preparation method according to claim 6, characterized in that: The amount of the third monomer in step (1) is 40 wt.% to 60 wt.% of the total amount of the third monomer; Preferably, the organic solvents in step (1) and step (2) each independently include any one of ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, and triethylene glycol dimethyl ether, or a combination of at least two thereof; Preferably, the amount of the organic solvent added in step (1) is 1 to 1.2 times the sum of the mass of the first monomer, the second monomer, and part of the third monomer; Preferably, the amount of the organic solvent added in step (2) is 5 to 10 times the mass of the initiator.

8. The preparation method according to claim 6 or 7, characterized in that: The heating in step (3) is to heat the temperature to 60-100° C. Preferably, in step (3), the first mixed solution and the second mixed solution are added under stirring; Preferably, the step (3) of adding the first mixed solution and the second mixed solution specifically comprises: controlling the first mixed solution and the second mixed solution to be added dropwise within 1 to 5 hours; Preferably, the insulation reaction time in step (3) is 0.5 to 5 hours.

9. The preparation method according to any one of claims 6 to 8, characterized in that: The heating in step (4) is to be raised to 120-160° C.; Preferably, the insulation reaction time in step (4) is 2 to 10 hours; Preferably, the weight average molecular weight of the high molecular weight polymer dispersant is 5000 to 100000 g / mol.

10. Use of the high molecular weight polymer dispersant according to any one of claims 1 to 5 in dispersing organic pigments.

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