阅读说明：本技术 一种用于水性uv塑胶漆的纳米色浆及其制备方法 (Nano color paste for water-based UV plastic paint and preparation method thereof ) 是由 匡民明 陆明 陆子菲 尚强强 于 2021-08-23 设计创作，主要内容包括：本发明公开了一种用于水性UV塑胶漆的纳米色浆及其制备方法,属于色浆技术领域,所述的用于水性UV塑胶漆的纳米色浆,按重量份计,包括：35～45份色粉、8～15份分散剂、1.2～2.5份稳定剂、1～3份润湿剂、0.2～0.5份消泡剂、0.1～0.4份防沉剂、0.1～0.3份含氨基的硅烷偶联剂、28～40份溶剂。所述的用于水性UV塑胶漆的纳米色浆具有良好的耐高温稳定性,能够有效的耐水煮,本发明通过加入所述的改性聚氨酯分散剂和稳定剂用于提高色粉的高稳定性、分散性能。(The invention discloses a nano color paste for an aqueous UV plastic paint and a preparation method thereof, belonging to the technical field of color paste, wherein the nano color paste for the aqueous UV plastic paint comprises the following components in parts by weight: 35-45 parts of toner, 8-15 parts of dispersing agent, 1.2-2.5 parts of stabilizing agent, 1-3 parts of wetting agent, 0.2-0.5 part of defoaming agent, 0.1-0.4 part of anti-settling agent, 0.1-0.3 part of amino-containing silane coupling agent and 28-40 parts of solvent. The nano color paste for the water-based UV plastic paint has good high-temperature stability and can effectively resist boiling, and the high stability and the dispersing performance of the toner are improved by adding the modified polyurethane dispersant and the stabilizer.)

1. The nanometer color paste for the water-based UV plastic paint is characterized by comprising the following components in parts by weight: 35-45 parts of toner, 8-15 parts of dispersing agent, 1.2-2.5 parts of stabilizing agent, 1-3 parts of wetting agent, 0.2-0.5 part of defoaming agent, 0.1-0.4 part of anti-settling agent, 0.1-0.3 part of amino-containing silane coupling agent and 28-40 parts of solvent.

2. The nano color paste for the water-based UV plastic paint as claimed in claim 1, which comprises the following components in parts by weight: 40-45 parts of toner, 10-15 parts of dispersing agent, 1.5-2.5 parts of stabilizing agent, 1.5-3 parts of wetting agent, 0.2-0.4 part of defoaming agent, 0.1-0.3 part of anti-settling agent, 0.1-0.25 part of amino-containing silane coupling agent and 30-40 parts of solvent.

3. The nano color paste for the water-based UV plastic paint as claimed in claim 1, which comprises the following components in parts by weight: 42 parts of toner, 14 parts of dispersing agent, 2 parts of stabilizing agent, 2 parts of wetting agent, 0.3 part of defoaming agent, 0.2 part of anti-settling agent, 0.2 part of amino-containing silane coupling agent and 39.5 parts of solvent.

4. The nano color paste for the water-based UV plastic paint as claimed in claim 1, wherein the toner is one of carbon black, titanium white, phthalocyanine blue, phthalocyanine green, azo, ultramarine, iron oxide, heterocyclic and condensed ring ketone pigments.

5. The nano color paste for the water-based UV plastic paint as claimed in claim 1, wherein the dispersant is a modified polyurethane dispersant, and the preparation method of the modified polyurethane dispersant comprises the following steps:

s01, adding 15-25 parts by weight of diisocyanate, 35-50 parts by weight of hydroxyl-terminated polybutadiene and 0.08-0.2 part by weight of first catalyst into a reaction kettle, and reacting at 80-95 ℃ for 1-3 h;

s02, adding 0.5-2 parts by weight of dimethylolbutyric acid into a reaction kettle, reacting at 70-85 ℃ for 1-3 h, adding 0.5-1.5 parts by weight of 3, 5-diethyl-2, 4-diaminotoluene into the reaction kettle, and reacting at 30-40 ℃ for 1-3 h to obtain a polyurethane dispersant;

s03, adding 20-30 parts by weight of polyethylene glycol monomethyl ether 550, 5-8 parts by weight of isatoic anhydride and 0.08-0.2 part by weight of a second catalyst into a three-neck flask, introducing nitrogen, and reacting at 90-110 ℃ for 1-4 hours to obtain a modifier;

s04, adding the modifier into the polyurethane dispersant, reacting for 2-5 h at 70-90 ℃, adding 1.5-3 parts by weight of propylene oxide, and reacting for 1-3 h at 35-50 ℃ to obtain the modified polyurethane dispersant.

6. The nano color paste for the water-based UV plastic paint as claimed in claim 5, wherein the diisocyanate is one of isophorone diisocyanate, 4' -dicyclohexylmethane diisocyanate and toluene diisocyanate; the first catalyst is tetrabutyltin, and the second catalyst is 4-dimethylaminopyridine.

7. The nano color paste for the water-based UV plastic paint as claimed in claim 1, wherein the stabilizer comprises a metal oxide and a rare earth oxide, the metal oxide is one of magnesium oxide, aluminum oxide and calcium oxide, and the rare earth oxide is cerium oxide.

8. The nano color paste for the water-based UV plastic paint as claimed in claim 1, wherein the amino-containing silane coupling agent is 3-aminopropyltrimethoxysilane.

9. The nano color paste for the water-based UV plastic paint as claimed in claim 1, wherein the wetting agent is glycerol or triethylene glycol monobutyl ether;

the anti-settling agent is one or more of bentonite, modified bentonite, fumed silica and hydroxyethyl cellulose;

the defoaming agent is one of C7-C9 higher alcohol, polyalkylsiloxane organic silicon, polyether modified organic silicon and polysiloxane;

the solvent is deionized water.

10. A preparation method of the nano color paste for the water-based UV plastic paint is characterized by comprising the following steps of:

s1, adding the silane coupling agent containing amino and the wetting agent into the solvent, and mixing uniformly to prepare a mixed solution;

and S2, adding the stabilizer into the mixed solution, stirring uniformly, adding the dispersant and the toner, stirring uniformly, adding the defoamer and the anti-settling agent, stirring uniformly, transferring to a nano sand mill, and grinding until the D95 is less than 0.2 mu m to obtain the nano color paste for the water-based UV plastic paint.

Technical Field

The invention relates to the technical field of color paste, in particular to nano color paste for water-based UV plastic paint and a preparation method thereof.

Background

The plastic paint, also called plastic paint, is a standard type plastic paint prepared by using thermoplastic acrylic resin as a matrix and adding high-grade applicable auxiliary agents and pigments. The paint has the characteristics of high hardness, high gloss, high degree of fullness, good interlayer adhesion, easy construction and the like, and is widely applied to the coating of products of plastic substrates. Such as plastic toys, plastic daily necessities, electrical products, plastic artware and the like.

The plastic paint is required to have good boiling resistance, and the color paste is required to have good high-temperature resistance, while the existing color paste generally does not have good high-temperature resistance.

Disclosure of Invention

The invention provides a nano color paste for an aqueous UV plastic paint and a preparation method thereof.

The invention adopts the following technical scheme for solving the technical problems:

a nanometer color paste for water-based UV plastic paint comprises the following components in parts by weight: 35-45 parts of toner, 8-15 parts of dispersing agent, 1.2-2.5 parts of stabilizing agent, 1-3 parts of wetting agent, 0.2-0.5 part of defoaming agent, 0.1-0.4 part of anti-settling agent, 0.1-0.3 part of amino-containing silane coupling agent and 28-40 parts of solvent.

As a preferred scheme, the nano color paste for the water-based UV plastic paint comprises the following components in parts by weight: 40-45 parts of toner, 10-15 parts of dispersing agent, 1.5-2.5 parts of stabilizing agent, 1.5-3 parts of wetting agent, 0.2-0.4 part of defoaming agent, 0.1-0.3 part of anti-settling agent, 0.1-0.25 part of amino-containing silane coupling agent and 30-40 parts of solvent.

As a preferred scheme, the nano color paste for the water-based UV plastic paint comprises the following components in parts by weight: 42 parts of toner, 14 parts of dispersing agent, 2 parts of stabilizing agent, 2 parts of wetting agent, 0.3 part of defoaming agent, 0.2 part of anti-settling agent, 0.2 part of amino-containing silane coupling agent and 39.5 parts of solvent.

Preferably, the toner is one of carbon black, titanium white, phthalocyanine blue, phthalocyanine green, azo, ultramarine, iron oxide, heterocyclic and condensed ring ketone pigments.

As a preferable scheme, the dispersant is a modified polyurethane dispersant, and the preparation method of the modified polyurethane dispersant comprises the following steps:

s01, adding 15-25 parts by weight of diisocyanate, 35-50 parts by weight of hydroxyl-terminated polybutadiene and 0.08-0.2 part by weight of first catalyst into a reaction kettle, and reacting at 80-95 ℃ for 1-3 h;

s02, adding 0.5-2 parts by weight of dimethylolbutyric acid into a reaction kettle, reacting at 70-85 ℃ for 1-3 h, adding 0.5-1.5 parts by weight of 3, 5-diethyl-2, 4-diaminotoluene into the reaction kettle, and reacting at 30-40 ℃ for 1-3 h to obtain a polyurethane dispersant;

s03, adding 20-30 parts by weight of polyethylene glycol monomethyl ether 550, 5-8 parts by weight of isatoic anhydride and 0.08-0.2 part by weight of a second catalyst into a three-neck flask, introducing nitrogen, and reacting at 90-110 ℃ for 1-4 hours to obtain a modifier;

s04, adding the modifier into the polyurethane dispersant, reacting for 2-5 h at 70-90 ℃, adding 1.5-3 parts by weight of propylene oxide, and reacting for 1-3 h at 35-50 ℃ to obtain the modified polyurethane dispersant.

The inventor of the invention finds that a prepolymer is generated by reacting diisocyanate and hydroxyl-terminated polybutadiene, a polyurethane dispersant is obtained by reacting a chain extender, and the polyurethane dispersant is modified to obtain a modified polyurethane dispersant which can obviously improve the stability and the dispersing ability of toner.

The reactive targeting group with an amino group is synthesized by the reaction of polyethylene glycol monomethyl ether 550 and isatoic anhydride, and the polyurethane is modified to improve the interaction force between the polyurethane and the surface of the toner, so that the polyurethane is not easy to fall off from the surface of the toner, the steric hindrance effect is improved, the dispersion stability of the toner is obviously improved, and the high temperature resistance and the boiling resistance of the toner are improved.

Preferably, the diisocyanate is one of isophorone diisocyanate, 4' -dicyclohexylmethane diisocyanate and toluene diisocyanate; the first catalyst is tetrabutyltin, and the second catalyst is 4-dimethylaminopyridine.

Preferably, the stabilizer comprises a metal oxide and a rare earth oxide, wherein the metal oxide is one of magnesium oxide, aluminum oxide and calcium oxide, and the rare earth oxide is cerium oxide.

The stabilizer provided by the invention can further improve the dispersing ability, high-temperature stability and boiling resistance of the toner.

As a preferable mode, the silane coupling agent containing amino is 3-aminopropyltrimethoxysilane.

Preferably, the humectant is glycerin or triethylene glycol monobutyl ether.

Preferably, the anti-settling agent is one or more of bentonite, modified bentonite, fumed silica and hydroxyethyl cellulose.

Preferably, the defoaming agent is one of C7-C9 higher alcohol, polyalkylsiloxane organic silicon, polyether modified organic silicon and polysiloxane.

As a preferred embodiment, the solvent is deionized water.

The invention also provides a preparation method of the nano color paste for the water-based UV plastic paint, which comprises the following steps:

s1, adding the silane coupling agent containing amino and the wetting agent into the solvent, and mixing uniformly to prepare a mixed solution;

and S2, adding the stabilizer into the mixed solution, stirring uniformly, adding the dispersant and the toner, stirring uniformly, adding the defoamer and the anti-settling agent, stirring uniformly, transferring to a nano sand mill, and grinding until the D95 is less than 0.2 mu m to obtain the nano color paste for the water-based UV plastic paint.

The inventors have found that the dispersibility and high temperature resistance and boiling resistance of the toner can be further improved by treating the stabilizer with an amino silane coupling agent.

The formula system is particularly suitable for carbon black toner, and the carbon black has the optimal dispersing performance and high temperature resistance.

The invention has the beneficial effects that: the nano color paste for the water-based UV plastic paint has good high-temperature stability and can effectively resist boiling, and the modified polyurethane dispersant and the stabilizer are added to improve the high stability and the dispersing performance of the toner.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below, and it is obvious that the described embodiments are a part of the embodiments of the present invention, but not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the present invention, the parts are all parts by weight unless otherwise specified.

Example 1

A nanometer color paste for water-based UV plastic paint comprises the following components in parts by weight: 42 parts of carbon black, 14 parts of modified polyurethane dispersant, 2 parts of stabilizer, 2 parts of glycerol, 0.3 part of defoaming agent DF-58, 0.2 part of fumed silica, 0.2 part of amino-containing silane coupling agent and 39.5 parts of deionized water.

The preparation method of the modified polyurethane dispersant comprises the following steps:

s01, adding 20 parts by weight of isophorone diisocyanate, 42 parts by weight of hydroxyl-terminated polybutadiene and 0.1 part by weight of tetrabutyltin into a reaction kettle, and reacting at 85 ℃ for 1.5 hours;

s02, adding 1.2 parts by weight of dimethylolbutyric acid into a reaction kettle, reacting at 80 ℃ for 1.2h, adding 1 part by weight of 3, 5-diethyl-2, 4-diaminotoluene into the reaction kettle, and reacting at 35 ℃ for 2h to obtain a polyurethane dispersant;

s03, adding 24 parts by weight of polyethylene glycol monomethyl ether 550, 6 parts by weight of isatoic anhydride and 0.1 part by weight of 4-dimethylaminopyridine into a three-neck flask, introducing nitrogen, and reacting at 95 ℃ for 2 hours to obtain a modifier;

s04, adding 10 parts by weight of modifier into 100 parts by weight of polyurethane dispersant, reacting for 3 hours at 80 ℃, adding 2 parts by weight of propylene oxide, and reacting for 2 hours at 40 ℃ to obtain the modified polyurethane dispersant.

The stabilizer comprises 1.5 parts by weight of aluminum oxide and 0.5 part by weight of cerium oxide.

The amino-containing silane coupling agent is 3-aminopropyltrimethoxysilane.

The nano color paste for the water-based UV plastic paint comprises the following steps:

s1, adding 3-aminopropyl trimethoxy silane and glycerol into deionized water, and uniformly mixing to prepare a mixed solution;

and S2, adding aluminum oxide and cerium oxide into the mixed solution, stirring at 800rpm for 60min, adding the modified polyurethane dispersant and carbon black, stirring at 1000rpm for 80min, adding the defoaming agent DF-58 and the fumed silica, stirring at 500rpm for 40min, transferring to a nano sand mill, and grinding until the D95 is less than 0.2 mu m to obtain the nano color paste for the water-based UV plastic paint.

Example 2

A nanometer color paste for water-based UV plastic paint comprises the following components in parts by weight: 35 parts of titanium dioxide, 10 parts of modified polyurethane dispersant, 1.2 parts of stabilizer, 3 parts of glycerol, 0.2 part of defoaming agent DF-58, 0.4 part of fumed silica, 0.1 part of amino-containing silane coupling agent and 28 parts of deionized water.

The preparation method of the modified polyurethane dispersant comprises the following steps:

s01, adding 20 parts by weight of toluene diisocyanate, 45 parts by weight of hydroxyl-terminated polybutadiene and 0.12 part by weight of tetrabutyltin into a reaction kettle, and reacting at 85 ℃ for 1.5 hours;

s02, adding 1.4 parts by weight of dimethylolbutyric acid into a reaction kettle, reacting at 80 ℃ for 1.2h, adding 0.9 part by weight of 3, 5-diethyl-2, 4-diaminotoluene into the reaction kettle, and reacting at 35 ℃ for 2h to obtain a polyurethane dispersant;

s03, adding 25 parts by weight of polyethylene glycol monomethyl ether 550, 8 parts by weight of isatoic anhydride and 0.1 part by weight of 4-dimethylaminopyridine into a three-neck flask, introducing nitrogen, and reacting at 95 ℃ for 2 hours to obtain a modifier;

s04, adding 10 parts by weight of modifier into 100 parts by weight of polyurethane dispersant, reacting for 3 hours at 80 ℃, adding 2 parts by weight of propylene oxide, and reacting for 2 hours at 40 ℃ to obtain the modified polyurethane dispersant.

The stabilizer comprises 0.8 weight part of aluminum oxide and 0.4 weight part of cerium oxide.

The amino-containing silane coupling agent is 3-aminopropyltrimethoxysilane.

The nano color paste for the water-based UV plastic paint comprises the following steps:

s1, adding 3-aminopropyl trimethoxy silane and glycerol into deionized water, and uniformly mixing to prepare a mixed solution;

and S2, adding aluminum oxide and cerium oxide into the mixed solution, stirring at 800rpm for 60min, adding the modified polyurethane dispersant and titanium dioxide, stirring at 1000rpm for 80min, adding the defoaming agent DF-58 and the fumed silica, stirring at 500rpm for 40min, transferring to a nano sand mill, and grinding until the D95 is less than 0.2 mu m to obtain the nano color paste for the water-based UV plastic paint.

Example 3

A nanometer color paste for water-based UV plastic paint comprises the following components in parts by weight: 45 parts of phthalocyanine blue, 13 parts of modified polyurethane dispersant, 2 parts of stabilizer, 1 part of glycerol, 0.5 part of defoaming agent DF-58, 0.1 part of fumed silica, 0.3 part of amino-containing silane coupling agent and 40 parts of deionized water.

The dispersant is a modified polyurethane dispersant, and the preparation method of the modified polyurethane dispersant comprises the following steps:

s01, adding 20 parts by weight of 4, 4' -dicyclohexylmethane diisocyanate, 38 parts by weight of hydroxyl-terminated polybutadiene and 0.1 part by weight of tetrabutyltin into a reaction kettle, and reacting at 85 ℃ for 1.5 hours;

s02, adding 1.5 parts by weight of dimethylolbutyric acid into a reaction kettle, reacting at 80 ℃ for 1.2h, adding 1.2 parts by weight of 3, 5-diethyl-2, 4-diaminotoluene into the reaction kettle, and reacting at 35 ℃ for 2h to obtain a polyurethane dispersant;

s03, adding 25 parts by weight of polyethylene glycol monomethyl ether 550, 7 parts by weight of isatoic anhydride and 0.1 part by weight of 4-dimethylaminopyridine into a three-neck flask, introducing nitrogen, and reacting at 95 ℃ for 2 hours to obtain a modifier;

s04, adding 10 parts by weight of modifier into 100 parts by weight of polyurethane dispersant, reacting for 3 hours at 80 ℃, adding 2 parts by weight of propylene oxide, and reacting for 2 hours at 40 ℃ to obtain the modified polyurethane dispersant.

The stabilizer comprises 1.2 parts by weight of alumina and 0.8 part by weight of cerium oxide.

The amino-containing silane coupling agent is 3-aminopropyltrimethoxysilane.

The nano color paste for the water-based UV plastic paint comprises the following steps:

s1, adding 3-aminopropyl trimethoxy silane and glycerol into deionized water, and uniformly mixing to prepare a mixed solution;

and S2, adding aluminum oxide and cerium oxide into the mixed solution, stirring at 800rpm for 60min, adding the modified polyurethane dispersant and phthalocyanine blue, stirring at 1000rpm for 80min, adding the defoamer DF-58 and the fumed silica, stirring at 500rpm for 40min, transferring to a nano sand mill, and grinding until the D95 is less than 0.2 mu m to obtain the nano color paste for the water-based UV plastic paint.

Comparative example 1

Comparative example 1 is different from example 1 in that the polyurethane dispersant described in comparative example 1 is used instead of the modified polyurethane dispersant, and the rest is the same.

The preparation method of the polyurethane dispersant comprises the following steps:

s01, adding 20 parts by weight of isophorone diisocyanate, 42 parts by weight of hydroxyl-terminated polybutadiene and 0.1 part by weight of tetrabutyltin into a reaction kettle, and reacting at 85 ℃ for 1.5 hours;

s02, adding 1.2 parts by weight of dimethylolbutyric acid into a reaction kettle, reacting at 80 ℃ for 1.2h, adding 1 part by weight of 3, 5-diethyl-2, 4-diaminotoluene into the reaction kettle, and reacting at 35 ℃ for 2h to obtain the polyurethane dispersant.

Comparative example 2

Comparative example 2 is different from example 1 in that the modified polyurethane dispersant is prepared by a method different from example 1, and a single polyethylene glycol monomethyl ether 550 modified polyurethane dispersant is used in this comparative example, but the other steps are the same.

The preparation method of the modified polyurethane dispersant comprises the following steps:

s01, adding 20 parts by weight of isophorone diisocyanate, 42 parts by weight of hydroxyl-terminated polybutadiene and 0.1 part by weight of tetrabutyltin into a reaction kettle, and reacting at 85 ℃ for 1.5 hours;

s02, adding 1.2 parts by weight of dimethylolbutyric acid into a reaction kettle, reacting at 80 ℃ for 1.2h, adding 1 part by weight of 3, 5-diethyl-2, 4-diaminotoluene into the reaction kettle, and reacting at 35 ℃ for 2h to obtain a polyurethane dispersant;

s03, adding 10 parts by weight of polyethylene glycol monomethyl ether 550 into 100 parts by weight of polyurethane dispersant, reacting at 80 ℃ for 3 hours, adding 2 parts by weight of propylene oxide, and reacting at 40 ℃ for 2 hours to obtain the modified polyurethane dispersant.

Comparative example 3

Comparative example 3 is different from example 1 in that the modification method of the modified polyurethane dispersant described in comparative example 3 is different from example 1, and in this comparative example, 1- (3-aminopropyl) imidazole modification is used, and the others are the same.

The preparation method of the modified polyurethane dispersant comprises the following steps:

s01, adding 20 parts by weight of isophorone diisocyanate, 42 parts by weight of hydroxyl-terminated polybutadiene and 0.1 part by weight of tetrabutyltin into a reaction kettle, and reacting at 85 ℃ for 1.5 hours;

s02, adding 1.2 parts by weight of dimethylolbutyric acid into a reaction kettle, reacting at 80 ℃ for 1.2h, adding 1 part by weight of 3, 5-diethyl-2, 4-diaminotoluene into the reaction kettle, and reacting at 35 ℃ for 2h to obtain a polyurethane dispersant;

s03, adding 10 parts by weight of 1- (3-aminopropyl) imidazole into 100 parts by weight of polyurethane dispersant, reacting for 3 hours at 80 ℃, adding 2 parts by weight of propylene oxide, and reacting for 2 hours at 40 ℃ to obtain the modified polyurethane dispersant.

Comparative example 4

Comparative example 4 differs from example 1 in that the stabilizer described in comparative example 4 differs from example 1, all else being equal.

The stabilizer comprises 1 part by weight of calcium oxide and 0.5 part by weight of cerium oxide.

Comparative example 5

Comparative example 5 differs from example 1 in that the stabilizer described in comparative example 5 differs from example 1, all else being equal.

The stabilizer is single calcium oxide, and the rest are the same.

Comparative example 6

Comparative example 6 is different from example 1 in that comparative example 6 does not contain the amino group-containing silane coupling agent, and the others are the same.

To further demonstrate the effect of the present invention, the following test methods were provided:

1. the nano color pastes of the examples 1 to 3 and the comparative examples 1 to 6 are respectively placed at 80 ℃ for 1 month, the average particle size before and after the placement is detected, and the test results are shown in Table 1.

2. According to the formula: 46 parts of water-based acrylic emulsion, 1.5 parts of water-based wetting agent, 0.8 part of defoaming agent, 3 parts of nano color paste and 47 parts of deionized water to prepare the plastic paint, wherein the nano color paste is the nano color paste described in examples 1-3 and comparative examples 1-6, the nano color paste is sprayed on a PVC plate for testing, the PVC plates corresponding to the examples 1-3 and comparative examples 1-6 are placed in the deionized water at 95 ℃ to be boiled for 120min, after the water boiling is completed, the PVC plates are taken out and placed for 120min at normal temperature, the change of a paint film is observed, and the test results are shown in table 1.

TABLE 1 test results

As can be seen from Table 1, the nano color paste for the water-based UV plastic paint has good high-temperature stability and boiling resistance.

Compared with the examples 1-3, the nano color paste with the optimized formula can improve the high-temperature stability.

Compared with the comparative examples 1 and 1-3, the modified polyurethane dispersant disclosed by the invention can obviously improve the high-temperature stability, the high-temperature stability is further improved after the polyurethane dispersant is modified, and in the preparation method of the modified polyurethane dispersant, the high-temperature stability and the boiling resistance are obviously reduced by singly modifying the polyurethane with the polyethylene glycol monomethyl ether 550 or other modifiers.

Comparing example 1 with comparative examples 4 and 5, it can be seen that the stabilizer including 1.5 parts by weight of alumina (metal oxide) and 0.5 parts by weight of cerium oxide (rare earth oxide) can improve the stability and boiling resistance more remarkably.

It is understood from comparative example 1 and comparative example 6 that the high temperature stability can be further improved by treating the stabilizer (metal oxide, rare earth oxide) with the amino group-containing silane coupling agent.

In light of the foregoing description of preferred embodiments according to the invention, it is clear that many changes and modifications can be made by the person skilled in the art without departing from the scope of the invention. The technical scope of the present invention is not limited to the contents of the specification, and must be determined according to the scope of the claims.