CN113088174B - A kind of water-based two-component polyurethane matte coating and its preparation method and application - Google Patents

Abstract

The present invention provides a water-based two-component polyurethane matte coating and a preparation method and application thereof. The water-based two-component polyurethane matte coating includes a component A and a component B, and the preparation raw materials of the component A include the following weights Parts of components: 60-90 parts of hydroxy acrylate emulsion; 5-20 parts of deionized water; 0-30 parts of powder; 0.5-2.5 parts of wetting and dispersing agent; 0.2-2 parts of thickener; defoamer 0.2-1 part; preservative 0.5-1.5 part; film-forming aid 0.2-2 part; the raw material of component B includes the following components by weight: 0.1-5 part of Covestro 307 water-based curing agent. The polyurethane matte coating of the invention can have a matte effect without adding a matting powder, can greatly improve the water resistance, permeability and stability of the coating, and is suitable for the coating field.

Description

A kind of water-based two-component polyurethane matte coating and its preparation method and application

technical field

The invention belongs to the technical field of coatings, and relates to a water-based two-component polyurethane matte coating and a preparation method and application thereof, in particular to a self-extinguishing water-based two-component polyurethane matte coating and its preparation method and application.

Background technique

With the strengthening of people's awareness of environmental protection, the national environmental protection laws and regulations have become more and more strict with the restrictions on the emission of volatile organic compounds (VOCs) in the coatings industry. Especially in the field of wood lacquer, various places have begun to implement the "oil-to-water" project. Waterborne two-component polyurethane coatings have bright application prospects as high-performance and green products. The water-based two-component polyurethane product (2K-WPU) is mainly composed of hydroxy acrylate resin and isocyanate curing agent, which can form a cross-linked network structure through chemical bonds. Therefore, its water resistance, adhesion, tensile strength and other properties will be significantly stronger than one-component products. At the same time, the main component of the coating does not contain organic solvents, which can truly achieve zero VOC emissions.

2K-WPU can be subdivided into high-gloss, semi-gloss, matte and other products in the field of coatings. Among them, water-based wood topcoats are mostly matte, usually three-point and five-point light. The more transparent, the better the product. Competitiveness. Water-based matte wood paint basically needs to add a matting agent, so the two most important factors affecting the transparency are the emulsion itself and the matting agent (matting powder, transparent powder).

At present, the mainstream matte products on the market are achieved by adding matting agents to the formula. The advantages of matting agents are high matting efficiency, stable effect, low price, and do not affect the feel. However, there are also shortcomings. Many matting powders have wax treatment on the surface, which is beneficial to improve the anti-settling property, but the transparency is poor. The addition of matting powder will greatly affect the water resistance of the coating, so in products with high water resistance requirements, the use of matting powder is greatly restricted.

Matting emulsion usually means that the emulsion is matte after forming a film, and no matting agent is added to the formula, or a small amount of matting agent can be added to achieve the desired gloss. Matting lotion can really solve the problems caused by matting powder, and it has little effect on the transparency of matte effect. It would be very good if you can find a suitable self-matting lotion, but there are not many related products on the market, mainly self-matting. The gloss stability of the emulsion is poor, and the requirements for the matching of raw materials in the formula are high.

CN103102792A discloses a water-based two-component polyurethane matte coating, which consists of a first component and a second component. Component one includes the following raw materials by mass percentage: hydroxy acrylic resin, dispersant, leveling agent, defoamer, anti-scratch assistant, surface additive, and matting powder; component two includes isocyanate curing agent. The coating contains urethane bonds and has properties such as chemical resistance, high hardness, abrasion resistance, weather resistance, and low gloss. However, the matting powder is added in this invention, which will affect the water resistance of the coating.

Therefore, in the art, it is expected to develop a self-extinguishing waterborne two-component polyurethane matte coating.

SUMMARY OF THE INVENTION

In view of the deficiencies of the prior art, the purpose of the present invention is to provide a water-based two-component polyurethane matte paint and its preparation method and application, especially a self-extinguishing water-based two-component polyurethane matte paint and its preparation method and application . The polyurethane matte coating of the present invention can have a matte effect without adding a matte powder, and can greatly improve the water resistance, permeability and stability of the coating.

For this purpose, the present invention adopts the following technical solutions:

On the one hand, the present invention provides a water-based two-component polyurethane matte coating, the water-based two-component polyurethane matte coating includes A component and B component, and the preparation raw materials of the A component include the following parts by weight: Components:

The raw material of the B component includes the following components in parts by weight:

Covestro 307 water-based curing agent 0.1 to 5 parts.

In the present invention, the hydroxy acrylate emulsion is used in combination with Covestro 307 water-based curing agent, and the difference in molecular structure between the hydroxy acrylate emulsion and the curing agent can be used to achieve the matte effect of the polyurethane coating. Hydroxy acrylate emulsions are not matte emulsions by themselves, but combined with other curing agents are normal gloss, increasing their range of use. Generally speaking, matte powder and treatment agent are mostly hydrophilic substances, which have a greater impact on the water resistance, adhesion and flexibility of the coating. Because the present invention does not add matte powder and treatment agent, the present invention The polyurethane coating has a great improvement in water resistance, adhesion and flexibility.

In the present invention, in the preparation raw materials of the A component, the dosage of the hydroxy acrylate emulsion can be 60 parts, 65 parts, 70 parts, 75 parts, 80 parts, 85 parts or 90 parts, etc.

In the present invention, among the raw materials for the preparation of the component A, the amount of deionized water may be 5 parts, 8 parts, 10 parts, 13 parts, 15 parts, 18 parts, or 20 parts, etc.

In the present invention, in the preparation raw materials of the A component, the amount of the powder can be 0, 5, 10, 15, 20, 25 or 30 parts, etc. When the amount of powder is 0 parts, that is, when no powder is used, the coating is a varnish product.

In the present invention, in the preparation raw materials of the A component, the amount of wetting and dispersing agent may be 0.5 parts, 1 part, 1.5 parts, 2 parts or 2.5 parts, etc.

In the present invention, in the preparation raw materials of the A component, the amount of the thickener can be 0.2 part, 0.4 part, 0.6 part, 0.8 part, 1 part, 1.2 part, 1.4 part, 1.8 part or 2 part, etc.

In the present invention, in the preparation raw materials of the A component, the amount of the defoaming agent can be 0.2 part, 0.4 part, 0.6 part, 0.8 part or 1 part, etc.

In the present invention, in the preparation raw materials of the component A, the amount of the preservative can be 0.5 part, 0.7 part, 0.9 part, 1 part, 1.3 part or 1.5 part, etc.

In the present invention, in the preparation raw materials of the A component, the amount of the film-forming aid can be 0.2 part, 0.4 part, 0.6 part, 0.8 part, 1 part, 1.2 part, 1.4 part, 1.8 part or 2 part, etc. .

In the present invention, among the raw materials of component B, the dosage of Covestro 307 water-based curing agent can be 0.1 part, 0.5 part, 0.8 part, 1 part, 1.5 part, 2 part, 2.5 part, 3 part, 3.5 part servings, 4 servings, 4.5 servings, or 5 servings, etc.

Preferably, the solid content of the hydroxy acrylate emulsion is 35%-55%, such as 35%, 40%, 45%, 50% or 55%, etc., and the hydroxyl content is 2%-4%, such as 2%, 2.5% %, 3%, 3.5% or 4% etc.

Preferably, the preparation raw materials of the hydroxy acrylate emulsion include the following components by weight:

Preferably, in the preparation raw materials of the hydroxy acrylate emulsion, the amount of deionized water may be 80 parts, 100 parts, 120 parts, 140 parts, 160 parts or 180 parts, etc.

Preferably, in the preparation raw materials of the hydroxyacrylate emulsion, the amount of the emulsifier can be 1 part, 3 parts, 5 parts, 8 parts or 10 parts, etc.

Preferably, in the preparation raw materials of the hydroxy acrylate emulsion, the amount of the structural monomer may be 65 parts, 70 parts, 75 parts, 80 parts or 85 parts, etc.

Preferably, in the preparation raw materials of the hydroxy acrylate emulsion, the amount of the acidic monomer may be 0.5 parts, 1 part, 2 parts, 3 parts, 4 parts or 5 parts, etc.

Preferably, in the raw materials for the preparation of the hydroxy acrylate emulsion, the amount of functional monomer used may be 15 parts, 20 parts, 25 parts or 30 parts, etc.

Preferably, in the preparation raw materials of the hydroxy acrylate emulsion, the amount of the buffer may be 0.2 part, 0.5 part, 1 part, 2 parts or 3 parts, etc.

Preferably, in the preparation raw materials of the hydroxyacrylate emulsion, the amount of the initiator may be 1 part, 2 parts or 3 parts, etc.

The preparation method of the hydroxyacrylate emulsion comprises the following steps:

(1) Preparation of pre-emulsion

Stir part of deionized water and part of emulsifier evenly, and then add structural monomer, acidic monomer and functional monomer to obtain a pre-emulsion;

(2) Preparation of seed emulsion

The remaining deionized water, the remaining emulsifier and the buffer are evenly stirred, part of the pre-emulsion prepared in step (1) is added, and then part of the initiator is added, and the reaction solution is kept under blue light to obtain a seed emulsion;

(3) Emulsion polymerization

Adding the remaining pre-emulsion and the remaining initiator to the seed emulsion in step (2), heating up, reacting, then cooling to room temperature, and filtering to obtain the hydroxy acrylate emulsion.

Preferably, the emulsifier comprises any one or a combination of at least two of ABEX VA-50, ABEX8028, DS-4, RS-610 or LA40-S.

Preferably, the structural monomer comprises methyl methacrylate, butyl methacrylate, isobutyl methacrylate, butyl acrylate, acrylonitrile, acrylamide, styrene or 2-isooctyl acrylate Any one or a combination of at least two.

Preferably, the acidic monomer includes any one or a combination of at least two of acrylic acid, methacrylic acid, crotonic acid, fumaric acid, itaconic acid, citraconic acid or maleic anhydride.

Preferably, the functional monomer includes hydroxypropyl methacrylate and/or hydroxyethyl methacrylate.

Preferably, the buffer includes any one or a combination of at least two of sodium carbonate, sodium bicarbonate, disodium hydrogen phosphate or sodium dihydrogen phosphate.

Preferably, the initiator includes ammonium persulfate and/or potassium persulfate.

Preferably, the part of deionized water in step (1) is 30 parts of deionized water.

Preferably, the part of the emulsifier in step (1) is 0.5 part of the emulsifier.

Preferably, the rotational speed of the stirring in step (1) is 100-500 rpm, such as 100 rpm, 200 rpm, 300 rpm, 400 rpm or 500 rpm, and the like.

Preferably, step (2) is carried out under the protection of protective gas.

Preferably, the protective gas is nitrogen.

Preferably, in step (2), adding part of the pre-emulsion prepared in step (1) is adding 1-30 parts (eg, 1 part, 10 parts, 20 parts or 30 parts, etc.) of the pre-emulsion.

Preferably, the adding part of the initiator in step (2) is adding 0.5 part of the initiator.

Preferably, the heat preservation in step (2) is for 10 to 30 minutes, such as 10 minutes, 20 minutes, or 30 minutes.

Preferably, the temperature increase in step (3) is to increase the temperature to 80°C.

Preferably, the reaction time of step (3) is 3 to 4 hours, such as 3 hours, 3.5 hours or 4 hours.

Preferably, the filtering in step (3) is filtering with a 200-mesh filter screen.

As a preferred technical solution of the present invention, the preparation raw materials of the A component include the following components in parts by weight:

The raw material of the B component includes the following components in parts by weight:

Covestro 307 water-based curing agent 0.1 to 5 parts.

Preferably, the powder includes rutile titanium dioxide.

Preferably, the particle size of the rutile titanium dioxide is 500-2000 mesh, such as 500 mesh, 800 mesh, 1000 mesh, 1300 mesh, 1500 mesh, 1800 mesh or 2000 mesh, etc.

Preferably, the wetting and dispersing agent includes any one or a combination of at least two of polyacrylate-based dispersants, polyurethane-based dispersants, polyamide-based dispersants or long-chain fatty acid-based dispersants.

Preferably, the thickener comprises polyacrylates and/or polyacrylates, preferably polyacrylates.

Preferably, the antifoaming agent comprises any one or a combination of at least two of nonionic polysiloxane, modified polysiloxane mixture, fatty acid antifoaming agent or fatty acid ester antifoaming agent, preferably nonionic Polysiloxane or modified polysiloxane mixture.

Preferably, the preservative includes any one or a combination of at least two of isothiazolinone preservatives, polyhexamethylene biguanide hydrochloride or imidazolidinyl urea, preferably isothiazolinone preservatives.

Preferably, the film-forming adjuvant comprises any one or a combination of at least two of propylene glycol methyl ether acetate, propylene glycol diacetate, dipropylene glycol butyl ether or dipropylene glycol methyl ether, preferably propylene glycol methyl ether acetate.

On the other hand, the present invention provides the preparation method of the above-mentioned water-based two-component polyurethane matte coating, the preparation method comprises the following steps:

(1) hydroxyacrylate emulsion, wetting and dispersing agent and defoamer are stirred to obtain the first mixture;

(2) adding powder and film-forming aid successively to the first mixture of step (1), and stirring to obtain a second mixture;

(3) adding thickener and preservative successively to the second mixture of step (2), stirring to obtain the third mixture;

(4) in the third mixture of step (3), add deionized water, filter, obtain A component;

(5) Mixing component A and component B uniformly to obtain the water-based two-component polyurethane matte coating.

Preferably, the rotational speed of the stirring in step (1) is 100-500 rpm, such as 100 rpm, 200 rpm, 300 rpm, 400 rpm or 500 rpm, and the like.

Preferably, the rotational speed of the stirring in step (2) is 400 rpm, and the stirring time is 20 min.

Preferably, the rotational speed of the stirring in step (3) is 400 rpm, and the stirring time is 20 min.

Preferably, gauze is used for the filtering in step (4), and the mesh number of the gauze is 200 meshes.

As a preferred technical solution of the present invention, adding deionized water in step (4) is to adjust the viscosity.

The B component in the present invention is a commercially available commercial product.

In another aspect, the present invention provides the application of the above-mentioned waterborne two-component polyurethane matte coating in coatings.

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

(1) The hydroxy acrylate emulsion in the present invention is used synergistically with Covestro 307 water-based curing agent, so that the prepared polyurethane coating has a matte effect (gloss: 13-35 degrees). The hydroxyl content can control the gloss of polyurethane coatings. The invention does not need to add matting powder, avoids powder sedimentation, and can reduce costs at the same time;

(2) The hydroxy acrylate emulsion of the present invention itself is not a matte emulsion, but combined with other curing agents, it is normal gloss, which increases its application range. Different from the special treatment of the matte emulsion, the emulsion itself is synthesized in a conventional way, so the stability of the emulsion is highly guaranteed, and there is no need to add additional special additives. The present invention uses the molecular structure of hydroxy acrylate emulsion and curing agent. The difference realizes the matte effect of polyurethane coating;

(3) Compared with the conventional polyurethane matte paint added with matte powder and treatment agent, the polyurethane matt paint of the present invention has higher water resistance (4.5-6h), adhesion (grade 0) and flexibility. improvement.

Detailed ways

The technical solutions of the present invention are further described below through specific embodiments. It should be understood by those skilled in the art that the embodiments are only for helping the understanding of the present invention, and should not be regarded as a specific limitation of the present invention. In the following examples, unless otherwise specified, the experimental methods used are conventional methods, and the materials and reagents used can be purchased from chemical companies.

Example 1

In this embodiment, a water-based two-component polyurethane matte coating is provided. The water-based two-component polyurethane matte coating includes a component A and a component B, and the preparation raw materials of the component A include the following parts by weight: Components:

The raw material of the B component includes the following components in parts by weight:

Covestro 307 water-based curing agent 0.1 part.

Among them, the solid content of the hydroxy acrylate emulsion is 35%, the hydroxyl content is 2%, and the particle size of the rutile type titanium dioxide is 500 meshes.

The preparation raw material of described hydroxy acrylate emulsion comprises the following components in parts by weight:

The preparation method of the hydroxyacrylate emulsion comprises the following steps:

(1) Preparation of pre-emulsion

Put 30 parts of deionized water and 0.5 part of emulsifier in a pre-emulsification bottle, stir evenly at 100 rpm, and then add structural monomers, acidic monomers and functional monomers to form a milky white pre-emulsion for later use;

(2) Preparation of seed emulsion

Under a nitrogen atmosphere, put the remaining deionized water, remaining emulsifier and buffer into a reaction flask with mechanical stirring, a thermometer and a reflux condenser, put it in an oil bath at a certain temperature, and add 1 step to the reaction flask. (1) the pre-emulsion prepared, then add 0.5 part of initiator, wait for the reaction solution to be in blue light and be incubated for 20min to obtain the seed emulsion;

(3) Emulsion polymerization

The remaining pre-emulsion and the remaining initiator are added dropwise to the seed emulsion in step (2). After dropping, the temperature is raised to 80° C. to react for 3 hours. Then, the liquid in the reaction flask is cooled to room temperature and filtered with a 200-mesh filter to obtain the obtained solution. Hydroxy acrylate emulsion.

The preparation method of the water-based two-component polyurethane matte coating comprises the following steps:

(1) stirring the hydroxy acrylate emulsion, the polyacrylate dispersant and the nonionic polysiloxane uniformly at a rotating speed of 100 rpm to obtain the first mixture;

(2) in the first mixture of step (1), add rutile type titanium dioxide, then add propylene glycol methyl ether acetate, stir 20min with the rotating speed of 400rpm, obtain the second mixture;

(3) adding polyacrylate and isothiazolinone antiseptics to the second mixture of step (2) successively, and stirring for 20min at a rotating speed of 400rpm to obtain the third mixture;

(4) in the third mixture of step (3), add deionized water, filter and discharge with 200 mesh gauze, obtain A component;

(5) Mixing component A and component B uniformly to obtain the water-based two-component polyurethane matte coating.

Example 2

In this embodiment, a water-based two-component polyurethane matte coating is provided. The water-based two-component polyurethane matte coating includes a component A and a component B, and the preparation raw materials of the component A include the following parts by weight: Components:

The raw material of the B component includes the following components in parts by weight:

Covestro 307 water-based curing agent 5 parts.

Among them, the solid content of the hydroxy acrylate emulsion is 55%, the hydroxyl content is 4%, and the particle size of the rutile type titanium dioxide is 1000 meshes.

The preparation raw material of described hydroxy acrylate emulsion comprises the following components in parts by weight:

The preparation method of the hydroxyacrylate emulsion comprises the following steps:

(1) Preparation of pre-emulsion

Put 30 parts of deionized water and 0.5 part of emulsifier in a pre-emulsification bottle, stir evenly at a speed of 200 rpm, and then add structural monomers, acidic monomers and functional monomers to form a milky white pre-emulsion for use;

(2) Preparation of seed emulsion

Under a nitrogen atmosphere, put the remaining deionized water, remaining emulsifier and buffer into a reaction flask with mechanical stirring, a thermometer and a reflux condenser, place it in an oil bath at a certain temperature, and add 5 steps to the reaction flask (1) the pre-emulsion prepared, then add 0.5 part of initiator, wait for the reaction solution to be in blue light and be incubated for 20min to obtain the seed emulsion;

(3) Emulsion polymerization

The remaining pre-emulsion and the remaining initiator are added dropwise to the seed emulsion in step (2), after dropping, the temperature is raised to 80° C., and the reaction is carried out for 3 h, and then the liquid in the reaction flask is cooled to room temperature, and filtered with a 200-mesh filter to obtain the obtained solution. Described hydroxy acrylate emulsion.

The preparation method of the water-based two-component polyurethane matte coating comprises the following steps:

(1) the hydroxy acrylate emulsion, the polyurethane-based dispersant and the modified polysiloxane mixture are uniformly stirred at a rotating speed of 200 rpm to obtain the first mixture;

(2) in the first mixture of step (1), add rutile type titanium dioxide, then add propylene glycol diacetate, stir 20min with the rotating speed of 400rpm, obtain the second mixture;

(3) adding polyacrylate and polyhexamethylene biguanide hydrochloride successively to the second mixture of step (2), and stirring for 20min at a rotating speed of 400rpm to obtain the third mixture;

(4) in the third mixture of step (3), add deionized water, filter and discharge with 200 mesh gauze, obtain A component;

(5) Mixing component A and component B uniformly to obtain the water-based two-component polyurethane matte coating.

Example 3

In this embodiment, a water-based two-component polyurethane matte coating is provided. The water-based two-component polyurethane matte coating includes a component A and a component B, and the preparation raw materials of the component A include the following parts by weight: Components:

The raw material of the B component includes the following components in parts by weight:

Covestro 307 water-based curing agent 0.5 parts.

Among them, the solid content of the hydroxy acrylate emulsion is 55%, and the hydroxyl content is 3%.

The preparation raw material of described hydroxy acrylate emulsion comprises the following components in parts by weight:

The preparation method of the hydroxyacrylate emulsion comprises the following steps:

(1) Preparation of pre-emulsion

Put 30 parts of deionized water and 0.5 part of emulsifier in a pre-emulsification bottle, stir evenly at a speed of 300 rpm, and then add structural monomers, acidic monomers and functional monomers to form a milky white pre-emulsion for use;

(2) Preparation of seed emulsion

Under a nitrogen atmosphere, put the remaining deionized water, remaining emulsifier and buffer into a reaction flask with mechanical stirring, a thermometer and a reflux condenser, place it in an oil bath at a certain temperature, and add 10 steps to the reaction flask (1) the prepared pre-emulsion, then add 0.5 part of initiator, wait for the reaction solution to be in blue light and keep warm for 10min to obtain seed emulsion;

(3) Emulsion polymerization

The remaining pre-emulsion and the remaining initiator are added dropwise to the seed emulsion in step (2). After dropping, the temperature is raised to 80° C., and the reaction is carried out for 3.5 hours. The hydroxyacrylate emulsion.

The preparation method of the water-based two-component polyurethane matte coating comprises the following steps:

(1) the hydroxy acrylate emulsion, polyamide-based dispersant and fatty acid defoamer are uniformly stirred at a rotating speed of 300 rpm to obtain the first mixture;

(2) in the first mixture of step (1), add dipropylene glycol butyl ether, stir 20min with the rotating speed of 400rpm, obtain the second mixture;

(3) adding polyacrylate and imidazolidinyl urea successively to the second mixture of step (2), and stirring for 20min at a rotating speed of 400rpm to obtain the third mixture;

(4) in the third mixture of step (3), add deionized water, filter and discharge with 200 mesh gauze, obtain A component;

(5) Mixing component A and component B uniformly to obtain the water-based two-component polyurethane matte coating.

Example 4

In this embodiment, a water-based two-component polyurethane matte coating is provided. The water-based two-component polyurethane matte coating includes a component A and a component B, and the preparation raw materials of the component A include the following parts by weight: Components:

The raw material of the B component includes the following components in parts by weight:

1 part of Covestro 307 water-based curing agent.

The solid content of the hydroxy acrylate emulsion is 40%, the hydroxyl content is 3.5%, and the particle size of the rutile type titanium dioxide is 2000 meshes.

The preparation raw material of described hydroxy acrylate emulsion comprises the following components in parts by weight:

The preparation method of the hydroxyacrylate emulsion comprises the following steps:

(1) Preparation of pre-emulsion

Put 30 parts of deionized water and 0.5 part of emulsifier in a pre-emulsification bottle, stir evenly at a speed of 400 rpm, and then add structural monomers, acidic monomers and functional monomers to form a milky white pre-emulsion for use;

(2) Preparation of seed emulsion

Under a nitrogen atmosphere, put the remaining deionized water, remaining emulsifier and buffer into a reaction flask with mechanical stirring, a thermometer and a reflux condenser, place it in an oil bath at a certain temperature, and add 30 steps to the reaction flask (1) the prepared pre-emulsion, then add 0.5 part of initiator, wait for the reaction solution to be in blue light and keep warm for 10min to obtain seed emulsion;

(3) Emulsion polymerization

The remaining pre-emulsion and the remaining initiator are added dropwise to the seed emulsion in step (2). After dropping, the temperature is raised to 80° C., and the reaction is carried out for 3.5 hours. The hydroxyacrylate emulsion.

The preparation method of the water-based two-component polyurethane matte coating comprises the following steps:

(1) stirring hydroxy acrylate emulsion, long-chain fatty acid dispersant and fatty acid ester defoamer at a rotating speed of 400rpm to obtain the first mixture;

(2) in the first mixture of step (1), add rutile type titanium dioxide, then add dipropylene glycol methyl ether, stir 20min with the rotating speed of 400rpm, obtain the second mixture;

(3) adding polyacrylate and isothiazolinone antiseptics to the second mixture of step (2) successively, and stirring for 20min at a rotating speed of 400rpm to obtain the third mixture;

(4) in the third mixture of step (3), add deionized water, filter and discharge with 200 mesh gauze, obtain A component;

(5) Mixing component A and component B uniformly to obtain the water-based two-component polyurethane matte coating.

Example 5

In this embodiment, a water-based two-component polyurethane matte coating is provided. The water-based two-component polyurethane matte coating includes a component A and a component B, and the preparation raw materials of the component A include the following parts by weight: Components:

The raw material of the B component includes the following components in parts by weight:

Covestro 307 water-based curing agent 3 parts.

Wherein, the solid content of the hydroxy acrylate emulsion is 50%, the hydroxyl content is 4%, and the particle size of the rutile type titanium dioxide is 800 meshes.

The preparation raw material of described hydroxy acrylate emulsion comprises the following components in parts by weight:

The preparation method of the hydroxyacrylate emulsion comprises the following steps:

(1) Preparation of pre-emulsion

Put 30 parts of deionized water and 0.5 part of emulsifier in a pre-emulsification bottle, stir evenly at a speed of 500 rpm, and then add structural monomers, acidic monomers and functional monomers to form a milky white pre-emulsion for use;

(2) Preparation of seed emulsion

Under a nitrogen atmosphere, put the remaining deionized water, remaining emulsifier and buffer into a reaction flask with mechanical stirring, a thermometer and a reflux condenser, place it in an oil bath at a certain temperature, and add 20 steps to the reaction flask (1) the prepared pre-emulsion, then add 0.5 part of initiator, and keep the temperature for 30min after the reaction solution is blue light to obtain the seed emulsion;

(3) Emulsion polymerization

The remaining pre-emulsion and the remaining initiator were added dropwise to the seed emulsion in step (2). After dropping, the temperature was raised to 80° C. and reacted for 4 hours. Then, the liquid in the reaction flask was cooled to room temperature and filtered through a 200-mesh filter to obtain Described hydroxy acrylate emulsion.

The preparation method of the water-based two-component polyurethane matte coating comprises the following steps:

(1) stirring the hydroxy acrylate emulsion, the polyacrylate dispersant and the modified polysiloxane mixture uniformly at a rotating speed of 500 rpm to obtain the first mixture;

(2) in the first mixture of step (1), add rutile type titanium dioxide, then add dipropylene glycol butyl ether, stir 20min with the rotating speed of 400rpm, obtain the second mixture;

(3) adding polyacrylate and polyhexamethylene biguanide hydrochloride successively to the second mixture of step (2), and stirring for 20min at a rotating speed of 400rpm to obtain the third mixture;

(4) in the third mixture of step (3), add deionized water, filter and discharge with 200 mesh gauze, obtain A component;

(5) Mixing component A and component B uniformly to obtain the water-based two-component polyurethane matte coating.

Example 6

In this embodiment, a water-based two-component polyurethane matte coating is provided. The water-based two-component polyurethane matte coating includes a component A and a component B, and the preparation raw materials of the component A include the following parts by weight: Components:

The raw material of the B component includes the following components in parts by weight:

Covestro 307 water-based curing agent 4 parts.

Among them, the solid content of the hydroxy acrylate emulsion is 45%, the hydroxyl content is 3.5%, and the particle size of the rutile type titanium dioxide is 1200 meshes.

The preparation raw material of described hydroxy acrylate emulsion comprises the following components in parts by weight:

The preparation method of the hydroxyacrylate emulsion comprises the following steps:

(1) Preparation of pre-emulsion

Put 30 parts of deionized water and 0.5 part of emulsifier in a pre-emulsification bottle, stir evenly at a speed of 300 rpm, and then add structural monomers, acidic monomers and functional monomers to form a milky white pre-emulsion for use;

(2) Preparation of seed emulsion

Under a nitrogen atmosphere, put the remaining deionized water, remaining emulsifier and buffer into a reaction flask with mechanical stirring, a thermometer and a reflux condenser, place it in an oil bath at a certain temperature, and add 25 steps to the reaction flask (1) the prepared pre-emulsion, then add 0.5 part of initiator, and keep the temperature for 30min after the reaction solution is blue light to obtain the seed emulsion;

(3) Emulsion polymerization

The remaining pre-emulsion and the remaining initiator were added dropwise to the seed emulsion in step (2). After dropping, the temperature was raised to 80° C. and reacted for 4 hours. Then, the liquid in the reaction flask was cooled to room temperature and filtered through a 200-mesh filter to obtain Described hydroxy acrylate emulsion.

The preparation method of the water-based two-component polyurethane matte coating comprises the following steps:

(1) the hydroxy acrylate emulsion, the polyurethane-based dispersant and the nonionic polysiloxane are uniformly stirred at a rotating speed of 300 rpm to obtain the first mixture;

(2) in the first mixture of step (1), add rutile type titanium dioxide, then add dipropylene glycol methyl ether, stir 20min with the rotating speed of 400rpm, obtain the second mixture;

(3) adding polyacrylate and imidazolidinyl urea successively to the second mixture of step (2), and stirring for 20min at a rotating speed of 400rpm to obtain the third mixture;

(4) in the third mixture of step (3), add deionized water, filter and discharge with 200 mesh gauze, obtain A component;

(5) Mixing component A and component B uniformly to obtain the water-based two-component polyurethane matte coating.

Example 7

The only difference between this example and Example 1 is that the hydroxyl content of the hydroxy acrylate emulsion in the raw material for the preparation of component A is 1%.

Comparative Example 1

The only difference between this comparative example and Example 1 is that the hydroxy acrylate emulsion in the preparation raw material of component A is replaced with the same amount of PA4816.

Comparative Example 2

The only difference between this comparative example and Example 1 is that the raw material Covestro 307 water-based curing agent in the B component is replaced with the same amount of Covestro 2655 curing agent.

The performance test is carried out to the water-based two-component polyurethane matte coatings of Examples 1-7 and Comparative Examples 1-2, and the test method is as follows:

(1) Adhesion test: test according to the method of GB/T 9286-1998;

(2) Gloss test: test according to the method of GB/T 9754-2007;

(3) Water resistance test: pour boiling water onto the surface of the paint film formed by the water-based two-component polyurethane matte paint, turn the disposable plastic cup upside down to keep the water, and observe the whitening time of the paint film;

(4) Hardness test: test according to the method of GB/T 6739-2006.

The performance test results are shown in Table 1.

Table 1

Adhesion (grade) Gloss (degree) Water resistance (h) hardness Example 1 0 35 4.5 H Example 2 0 13 6 3H Example 3 0 26 4.6 2H Example 4 0 twenty four 5 2H Example 5 0 15 6 3H Example 6 0 28 5 H Example 7 2 40 3 HB Comparative Example 1 0 80 4.5 2H Comparative Example 2 0 77 5 2H

As can be seen from Table 1, the water-based two-component polyurethane matte coatings prepared in Examples 1-6 have good adhesion (grade 0), have a matte effect (gloss: 13-35 degrees), and have relatively Good water resistance (4.5-6h) and hardness (H-3H).

Compared with Example 1, the adhesion, water resistance and hardness of the water-based two-component polyurethane matte coating prepared in Example 7 are all deteriorated, and the matte effect is deteriorated.

Compared with Example 1, the matte effect of the water-based two-component polyurethane matte coatings prepared in Comparative Example 1 and Comparative Example 2 disappeared and showed normal gloss.

The applicant declares that the present invention illustrates the water-based two-component polyurethane matte coating of the present invention and its preparation method and application through the above-mentioned examples, but the present invention is not limited to the above-mentioned examples, that is, it does not mean that the present invention must rely on the above-mentioned examples. Examples can be implemented. Those skilled in the art should understand that any improvement of the present invention, the equivalent replacement of each raw material of the product of the present invention, the addition of auxiliary components, the selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

Claims (35)

1. a water-based two-component polyurethane matte paint, is characterized in that, described water-based two-component polyurethane matte paint is made up of A component and B component, and the preparation raw material of described A component is made up of following parts by weight The composition of the components: 60-90 parts of hydroxy acrylate emulsion; 5-20 parts of deionized water; Powder 0～30 parts; Wetting and dispersing agent 0.5～2.5 parts; Thickener 0.2 to 2 parts; Defoamer 0.2 to 1 part; Preservatives: 0.5 to 1.5 parts; 0.2 to 2 parts of film-forming aids; The raw material of the B component is made up of the following components by weight: Covestro 307 water-based curing agent 0.1 to 5 parts; The solid content of the hydroxyl acrylate emulsion is 35%-55%, and the hydroxyl content is 2%-4%; The preparation raw material of described hydroxy acrylate emulsion is made up of the following components by weight: 80-180 parts of deionized water; 1 to 10 parts of emulsifier; 65-85 parts of structural monomers; Acid monomer 0.5 to 5 parts; 15 to 30 functional monomers; Buffer 0.2 to 3 copies; 1 to 3 parts of initiator; The structural monomer includes any one of methyl methacrylate, butyl methacrylate, isobutyl methacrylate, butyl acrylate, acrylonitrile, acrylamide, styrene or 2-isooctyl acrylate or a combination of at least two; The acidic monomer includes any one or a combination of at least two of acrylic acid, methacrylic acid, crotonic acid, fumaric acid, itaconic acid, citraconic acid or maleic anhydride; The functional monomer includes hydroxypropyl methacrylate and/or hydroxyethyl methacrylate. 2. water-based two-component polyurethane matte paint according to claim 1, is characterized in that, the preparation method of described hydroxy acrylate emulsion comprises the following steps: (1) Preparation of pre-emulsion Stir part of deionized water and part of emulsifier evenly, and then add structural monomer, acidic monomer and functional monomer to obtain a pre-emulsion; (2) Preparation of seed emulsion Stir the remaining deionized water, the remaining emulsifier and the buffer evenly, add part of the pre-emulsion prepared in step (1), and then add part of the initiator, and keep the reaction solution in blue light to obtain a seed emulsion; (3) Emulsion polymerization The remaining pre-emulsion and the remaining initiator are added to the seed emulsion in step (2), the temperature is raised, reacted, and then cooled to room temperature and filtered to obtain the hydroxy acrylate emulsion. 3. water-based two-component polyurethane matte paint according to claim 1, is characterized in that, described emulsifier comprises any one in ABEX VA-50, ABEX8028, DS-4, RS-610 or LA40-S or a combination of at least two. 4. water-based two-component polyurethane matte paint according to claim 1, is characterized in that, described buffer comprises any one in sodium carbonate, sodium bicarbonate, disodium hydrogen phosphate or sodium dihydrogen phosphate or at least combination of the two. 5. The water-based two-component polyurethane matte coating according to claim 1, wherein the initiator comprises ammonium persulfate and/or potassium persulfate. 6 . The water-based two-component polyurethane matte coating according to claim 2 , wherein the part of deionized water in step (1) is 30 parts of deionized water. 7 . 7 . The water-based two-component polyurethane matte coating according to claim 2 , wherein the part of the emulsifier in step (1) is 0.5 part of the emulsifier. 8 . 8 . The water-based two-component polyurethane matte coating according to claim 2 , wherein the stirring speed in step (1) is 100-500 rpm. 9 . 9 . The water-based two-component polyurethane matte coating according to claim 2 , wherein step (2) is carried out under the protection of protective gas. 10 . 10 . The water-based two-component polyurethane matte coating according to claim 9 , wherein the protective gas is nitrogen. 11 . 11 . The water-based two-component polyurethane matte coating according to claim 2 , wherein the pre-emulsion prepared by adding part of step (1) in step (2) is adding 1-30 parts of pre-emulsion. 12 . 12 . The water-based two-component polyurethane matte coating according to claim 2 , wherein the adding part of the initiator in step (2) is adding 0.5 part of the initiator. 13 . 13 . The water-based two-component polyurethane matte coating according to claim 2 , wherein the heat preservation in step (2) is for 10-30 min. 14 . 14 . The water-based two-component polyurethane matte coating according to claim 2 , wherein the temperature in step (3) is increased to 80° C. 15 . 15 . The water-based two-component polyurethane matte coating according to claim 2 , wherein the reaction time of step (3) is 3-4 h. 16 . 16 . The water-based two-component polyurethane matte coating according to claim 2 , wherein the filtering in step (3) is filtering with a 200-mesh filter screen. 17 . 17. water-based two-component polyurethane matte paint according to claim 1, is characterized in that, the preparation raw material of described A component is made up of the following components by weight: 60-90 parts of hydroxy acrylate emulsion; 5-20 parts of deionized water; 18-25 parts of powder; Wetting and dispersing agent 1.5 to 2 parts; Thickener 0.5 to 1.5 parts; Defoamer 0.5 to 1 part; Preservatives: 0.8 to 1.2 servings; 0.5 to 1 part of film-forming aid; The raw material of the B component is made up of the following components by weight: Covestro 307 water-based curing agent 0.1 to 5 parts. 18. The water-based two-component polyurethane matte coating according to claim 1, wherein the powder comprises rutile titanium dioxide. 19. The water-based two-component polyurethane matte coating according to claim 18, wherein the particle size of the rutile titanium dioxide is 500-2000 mesh. 20. The water-based two-component polyurethane matte coating according to claim 1, wherein the wetting and dispersing agent comprises a polyacrylate-based dispersant, a polyurethane-based dispersant, a polyamide-based dispersant or a long-chain fatty acid Any one or a combination of at least two of the dispersants. 21. The water-based two-component polyurethane matte coating according to claim 20, wherein the wetting and dispersing agent is a polyacrylate dispersing agent. 22. The water-based two-component polyurethane matte coating according to claim 1, wherein the thickener comprises polyacrylate and/or polyacrylate. 23. The water-based two-component polyurethane matte coating according to claim 22, wherein the thickener is polyacrylate. 24. The water-based two-component polyurethane matte coating according to claim 1, wherein the defoamer comprises nonionic polysiloxane, modified polysiloxane mixture, fatty acid defoamer or fatty acid Any one or a combination of at least two of the ester defoamers. 25. The water-based two-component polyurethane matte coating according to claim 24, wherein the defoamer is a nonionic polysiloxane or a modified polysiloxane mixture. 26. The water-based two-component polyurethane matte coating according to claim 1, wherein the preservative comprises any of isothiazolinone preservatives, polyhexamethylene biguanide hydrochloride or imidazolidinyl urea one or a combination of at least two. 27. The water-based two-component polyurethane matte coating according to claim 26, wherein the preservative is an isothiazolinone preservative. 28. The water-based two-component polyurethane matte coating according to claim 1, wherein the film-forming aid comprises propylene glycol methyl ether acetate, propylene glycol diacetate, dipropylene glycol butyl ether or dipropylene glycol methyl ether. any one or a combination of at least two. 29. The water-based two-component polyurethane matte coating according to claim 28, wherein the film-forming aid is propylene glycol methyl ether acetate. 30. The preparation method of the water-based two-component polyurethane matte coating according to any one of claims 1-29, wherein the preparation method comprises the following steps: (1) stirring the hydroxy acrylate emulsion, the wetting and dispersing agent and the defoaming agent to obtain the first mixture; (2) adding powder and film-forming aid to the first mixture in step (1) in turn, and stirring to obtain a second mixture; (3) adding thickener and preservative to the second mixture in step (2) in turn, and stirring to obtain a third mixture; (4) adding deionized water to the third mixture of step (3), filtering to obtain component A; (5) Mixing components A and B evenly to obtain the water-based two-component polyurethane matte coating. 31 . The preparation method according to claim 30 , wherein the stirring speed in step (1) is 100-500 rpm. 32 . 32 . The preparation method according to claim 30 , wherein the stirring speed in step (2) is 400 rpm, and the stirring time is 20 min. 33 . 33. The preparation method according to claim 30, wherein the stirring speed of the step (3) is 400 rpm, and the stirring time is 20 min. 34 . The preparation method according to claim 30 , wherein in step (4), gauze is used for the filtration, and the mesh number of the gauze is 200 meshes. 35 . 35. The application of the water-based two-component polyurethane matte coating according to any one of claims 1-29 in coatings.