CN1624009A - Hydroxyl acrylic acid emulsion with microgel nuclear structure and preparation process and application thereof - Google Patents

Abstract

The invention relates to a preparation method of a hydroxyacrylic acid emulsion with a microgel core structure. The vinyl silane coupling agent is used as a crosslinking agent, and the vinyl silane coupling agent and acrylate monomers are firstly copolymerized to obtain A core with a microgel structure, and then carry out copolymerization of hydroxyl-containing vinyl monomers and acrylate monomers on the surface of the core to form a shell rich in hydroxyl, and obtain a hydroxyl acrylic emulsion with a microgel core structure; the emulsion has Core-shell structure, the core part is hydrophobic siloxane, the shell part contains hydroxyl group with strong hydrophilicity, and the shell layer can shield the siloxane condensation reaction between particles; Hydroxy acrylic acid emulsion with glue core structure is used to prepare two-component water-based polyurethane; the obtained two-component water-based polyurethane not only has high crosslinking density, but also has low production cost; Sag, film thickness and appearance, improve coating curing speed.

Description

Hydroxy acrylic emulsion with microgel core structure and its preparation method and application

Technical field

The invention relates to a preparation method of a hydroxyacrylic acid emulsion with a microgel core structure.

The invention also relates to the hydroxyacrylic acid emulsion with microgel core structure prepared by the method.

The present invention also relates to a method for preparing a two-component water-based polyurethane with high cross-linking density, which is especially suitable for coatings, leather finishing agents, fabric treatment, adhesives, and the like, using the hydroxyacrylic acid emulsion with a microgel core structure.

Background technique

Microgels are intramolecularly cross-linked polymer microspheres whose molecular structure is between branched macromolecules and macroscopic network polymers. A microgel particle is a macromolecule, and the macromolecular chain is limited to a certain area for intramolecular cross-linking to form a network structure. The microgel is added to the paint, which can effectively improve the rheology of the paint compound, make the paint have good pseudoplasticity and thixotropy, and thus make the paint have excellent anti-sagging when spraying. Therefore, the coating can conform to the trend of environmental protection and develop towards the direction of high solid content and low solvent volatilization. In addition, it can also improve the appearance of the coating and the dispersion of pigments in the coating. The prepared coating has excellent processability, mechanical properties and excellent durability, and is mainly used in preparing high-grade coatings or modifying coatings.

As early as 1934, Staudinger et al. synthesized this intramolecular cross-linked product. In 1948, Schulze and Crouch found that the viscosity of the soluble part of styrene/butadiene copolymer dropped sharply after gelation. The methods for preparing microgels include emulsion polymerization, dispersion polymerization, solution polymerization and precipitation polymerization. Since each latex particle is isolated from each other in emulsion polymerization, it is beneficial to carry out polymerization reaction and form a cross-linked structure in each reaction micro-region, that is, the latex particle. This cross-linked structure is limited within the range of a single latex particle, and finally a The latex particles become a polymer microgel particle, so emulsion polymerization is currently the most commonly used and most effective polymerization method for synthesizing microgels.

The preparation of microgels has been reported in many patents, such as US3,880,796, US4,025,474, US4,055,607, US4,075,141 and so on. At present, acrylic microgels are prepared by free-radical polymerization of multifunctional monomers or free-radical copolymerization of multifunctional monomers and difunctional monomers in an appropriate system. The more commonly used multifunctional monomers are divinylbenzene, ethylene glycol dimethacrylate, butylene glycol dimethacrylate, trimethylolpropane triacrylate, diallyl terephthalate , Isocyanuric acid triacrylate, etc. During the preparation of this type of microgel, as the reaction continues, due to factors such as cross-linking network and steric barriers, some double bonds that do not participate in intramolecular cross-linking increase the residual active points on the surface of latex particles, and the latex particles Collision between them leads to cross-linking and aggregation. At the same time, due to the increase of the degree of crosslinking, the structure of the latex particles becomes more compact, and the binding force between the emulsifier molecules and the latex particles decreases, so that the emulsifier on the surface of the latex particles is easy to fall off under the action of thermal movement or mechanical force, so that When the latex particles collide with each other, due to the instant desorption of the emulsifier, the latex particles are more likely to coalesce. Both of these reasons lead to a decrease in stability during the synthesis process and a low solid content of the product.

Silane coupling agents were first developed as treatment agents for glass fibers in glass fiber reinforced plastics. The general formula of the silane coupling agent is: Y(CH ₂ )nSiX ₃ [n=0-3, X is a hydrolyzable group; Y is an organic functional group]. According to the different organic functional groups, silane coupling agents can be divided into amines, vinyls, epoxies, acrylates, mercaptos, ureas, etc. The general formula of vinyl silane coupling agent is: CH ₂ =CH(CH ₂ ) _n SiX ₃ ; X is usually chloro, methoxy, ethoxy, methoxyethoxy, acetoxy, etc., these When the group is hydrolyzed, silanol [Si(OH) ₃ ] is generated, and the silanol can be self-condensed into Si-O-Si bonds, and can be combined with the hydroxyl group on the substrate or pigment (M) to form a stable Si-O-Si bond. OM bond, and vinyl can be copolymerized with acrylate monomers.

Vinyl silane coupling agent contains three hydrolyzable siloxane groups, and the local concentration of siloxane functional groups in the latex particles is relatively high during the polymerization reaction, and it is easy to carry out intramolecular crosslinking. The hydrolysis and condensation reaction rate of siloxane is affected by the type of vinyl silane coupling agent monomer, pH value, temperature and other factors. In the preparation stage of the hydroxyacrylic acid emulsion, the cross-linking density of the microgel particles can be effectively controlled by selecting the appropriate polymerization process and the type of vinyl silane coupling agent. At the same time, the low surface energy organosiloxane formed by the condensation of vinyl silane coupling agent tends to be distributed in the interior of the latex particles. By rationally selecting the emulsifier, it is possible to obtain a particle size less than 80nm and a solid content of more than 40%. Hydroxy acrylic with glue core structure.

Contents of Invention

The object of the present invention is to aim at the problems existing in the prior art, provide a kind of with vinyl silane coupling agent as crosslinking agent, have the preparation method of the hydroxyl acrylic acid emulsion of microgel nucleus structure, first vinyl silane coupling agent Copolymerize with acrylate monomers to obtain a core with a microgel structure, and then carry out copolymerization of hydroxyl-containing vinyl monomers and acrylate monomers on the surface of the core to form a hydroxyl-rich shell to obtain a microgel Hydroxy acrylic emulsion with core structure.

The purpose of the present invention is to provide the hydroxyacrylic acid emulsion with microgel core structure prepared by the method. The hydroxyacrylic acid emulsion with the microgel core structure undergoes intramolecular cross-linking due to hydrolysis and condensation of the vinyl silane coupling agent with a high number of functional groups, and the obtained latex particle has a high cross-linking density inside. The shell part of the latex has many reactive hydroxyl groups, and these groups can be combined with a multifunctional curing agent to obtain a network polymer with a heterogeneous structure. After curing to form a film, the core with microgel structure is embedded in the coating film, just like the concrete mixed with pebbles, endowing the coating film with excellent tensile strength, impact strength, water resistance, heat resistance, Weather resistance and light resistance and other properties.

The object of the present invention is also to provide the said hydroxy acrylic acid emulsion with microgel core structure to be used for preparing a kind of high cross-linking density two-component waterborne polyurethane that is especially suitable for the fields such as coating, leather finishing agent, fabric treatment, adhesive agent Methods.

The present invention adopts thermal initiation system, first prepares seed emulsion, and then adopts semi-continuous polymerization process to prepare respectively the core layer containing microgel structure and the shell layer containing hydroxyl group, and then the hydroxyl group with microgel core structure of the present invention can be obtained. Acrylic emulsion.

The preparation method of the hydroxyacrylic acid emulsion with microgel core structure of the present invention comprises the steps:

(1) Preparation of seeds

Add water and emulsifier into the reaction kettle, add alkyl (meth)acrylate, alkenyl carboxylic acid, vinyl aromatic compound and vinyl silane coupling agent under strong stirring, raise the temperature to 60-90°C, add Initiator solution, react for 20-40 minutes, and the emulsion shows obvious blue light to obtain the seed emulsion;

The mass parts of each component are as follows:

Water 60～130 parts

Emulsifier 3～8 parts

Alkyl (meth)acrylate 1-10 parts

Alkenyl carboxylic acid 0～5 parts

Vinyl aromatic compound 1～10 parts

Vinyl silane coupling agent 0.5~5 parts

Initiator solution (concentration is 1% by mass) 2 to 6 parts;

(2) Preparation of nucleus

The mixture of alkyl (meth)acrylate, vinyl aromatic compound, vinyl silane coupling agent, alkenyl carboxylic acid, divinyl unsaturated monomer, water, emulsifier, and initiator solution in 1 Dropping them into the seed emulsion obtained in (1) at the same time within 3 hours, and keeping the reaction temperature at 60-90°C for an hour;

The mass parts of each component are as follows:

Water 0～60 parts

Emulsifier 0～3 parts

Alkyl (meth)acrylate 20-80 parts

Alkenyl carboxylic acid 0～5 parts

Vinyl aromatic compound 1～10 parts

Vinyl silane coupling agent 0.5~5 parts

Divinyl unsaturated monomer 0.1-2 parts

Initiator solution (concentration is 1% mass 0～40 parts;

(3) Preparation of the shell

Mix the mixture of alkyl (meth)acrylate, hydroxyalkyl (meth)acrylate, vinyl aromatic compound, alkenyl carboxylic acid, water, emulsifier, and initiator solution within 2 to 5 hours Drop them into the reaction kettle at the same time, keep the reaction temperature at 60-90°C, and keep warm for 1-2 hours after the reaction, to obtain a hydroxyacrylic acid emulsion with a microgel core structure with a solid content of 30-50%; each of the groups The parts by mass are as follows:

Water 0～60 parts

Emulsifier 0～3 parts

Alkyl (meth)acrylate 20-80 parts

(Meth) hydroxyalkyl acrylate 10-30 parts

Alkenyl carboxylic acid 0.5~5 parts

Vinyl aromatic compound 1～10 parts

Initiator solution (concentration is 1% mass) 0～40 parts;

The alkyl (meth)acrylate, the number of alkyl carbon atoms is C1-C15, can be methyl methacrylate, ethyl methacrylate, butyl methacrylate, pentyl methacrylate, methacrylic acid One of hexyl, n-octyl methacrylate, isooctyl methacrylate, methyl acrylate, ethyl acrylate, butyl acrylate, amyl acrylate, hexyl acrylate, n-octyl acrylate, isooctyl acrylate or more than one mixture;

The hydroxyalkyl (meth)acrylate, the number of alkyl carbon atoms is C1～C15, can be 2-hydroxyethyl acrylate, 3-hydroxypropyl acrylate, 2-hydroxybutyl acrylate, acrylate- One or a mixture of two or more of 5-hydroxypentyl ester, 6-hydroxyhexyl acrylate, 2-hydroxyethyl methacrylate, and 2-hydroxypropyl methacrylate;

The alkenyl carboxylic acid, the number of alkyl carbon atoms is C1-C15, can be one or a mixture of two or more of acrylic acid, methacrylic acid, and itaconic acid;

The vinyl aromatic compound is one or more of styrene, α-methylstyrene, 2-chlorostyrene, 3-tert-butylstyrene, and 3,4-dimethylstyrene mixture.

The vinyl silane coupling agent is vinyl trimethoxy silane, vinyl methoxy diethoxy silane, vinyl triethoxy silane, vinyl ethoxy diisopropoxy silane, vinyl One or more mixtures of triisopropoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropyltriisopropoxysilane;

The divinyl unsaturated monomers are divinylbenzene, ethylene glycol dimethacrylate, triethylene glycol dimethacrylate, trimethylolpropane methacrylate, dimethacrylic acid One or more mixtures of tetraethylene glycol esters;

The initiator is a persulfate such as potassium persulfate or ammonium persulfate, an azo such as azobisisobutyronitrile and the like.

Described emulsifying agent is the mixture of anionic emulsifying agent and nonionic emulsifying agent, and wherein anionic emulsifying agent has longer hydrophobic alkyl chain, and hydrophilic part can be carboxylate, sulfonate, sulfate, phosphate, Mixtures of these with polyethoxy groups are also possible. Among them, the anionic emulsifiers are: sodium lauryl sulfate, sodium dodecylbenzenesulfonate, disodium alkyl diphenyl ether sulfonate, disodium ethoxysulfosuccinate, sodium vinylsulfonate, ethyl One or a mixture of sodium oxyphenol ether sulfate, sodium alkylamido vinyl sulfonate, sodium allyl ether hydroxysulfonate, and phenol ether phosphate. Nonionic emulsifiers include fatty alcohol polyoxyethylene ether, nonylphenol polyoxyethylene ether, octylphenol polyoxyethylene ether, ethoxylated propoxylated fatty alcohol, and sorbitan ester. a mixture of the above.

The invention uses vinyl silane coupling agent as crosslinking agent to prepare hydroxyacrylic acid emulsion with microgel core structure. When the emulsion is used together with polyisocyanate, it only needs shallow cross-linking and curing, and the coating film dries quickly to obtain a two-component water-based polyurethane with high cross-linking density. The film not only has excellent mechanical properties, adhesion, weather resistance, Stain resistance, abrasion resistance and air permeability, and the required amount of polyisocyanate curing agent is small, and the production cost of the product is low.

The present invention has the method that the hydroxyl acrylic acid emulsion of microgel core structure is used for preparing two-component waterborne polyurethane comprises the steps:

(1) The above-mentioned hydroxyacrylic acid emulsion is added to a stirring tank, and under the stirring condition of 200-1000rpm, the film-forming aid, defoamer and thickener are slowly added to the hydroxyacrylic acid emulsion, and stirred for 10-30min.

(2) Slowly add the hydrophilic modified polyisocyanate curing agent into the hydroxyacrylic acid emulsion, stir for 5 to 15 minutes, and then add a certain amount of water to a suitable construction viscosity.

The mass parts of each component are as follows:

Hydroxy Acrylic Emulsion 100 parts

Curing agent 10-40 parts

Coalescing agent 0～5 parts

Defoamer 0.05～0.5 parts

Thickener 0.1～1 parts

The above-mentioned curing agent can be nonionic polyether and or anionic hydrophilic modified polyisocyanate, such as VPLS2150BA, VPLS2306, VPLS2319, VPLS2336 of Bayer Company, WT-2102 of Rhodia Company, AQ210 of NPU Company, etc.

The above-mentioned film-forming aids can be alcohol ether solvents, such as ethylene glycol ethyl ether, ethylene glycol monobutyl ether, diethylene glycol butyl ether, propylene glycol methyl ether, propylene glycol monobutyl ether, dipropylene glycol methyl ether one or one above mixture.

The above-mentioned defoamer can be TEGO-800, TEGO-805, TEGO-810, TEGO-815, TEGO-825 of TEGO company, or one or more mixtures of BYK company BYK-019, BYK-020, etc. .

The above-mentioned thickener can be one or more mixtures of cellulose type such as hydroxyethyl cellulose, alkali-swellable acrylate type such as RM-2020 and polyurethane associative thickener such as SN-612.

The hydroxyacrylic acid emulsion with microgel core structure of the present invention and the obtained two-component water-based polyurethane have the following advantages compared with the prior art:

1. The preparation method of the present invention uses vinyl silane coupling agent as crosslinking agent, which has high crosslinking density and high solid content;

2. The emulsion obtained by the preparation method of the present invention has a core-shell structure, the core part is hydrophobic siloxane, the shell part contains hydroxyl groups with strong hydrophilicity, and the shell layer can shield the siloxane condensation reaction between particles;

3. The emulsion obtained by the present invention has a core-shell structure, the core part is a microgel structure, and the shell part is used for film formation and curing. The obtained two-component water-based polyurethane not only has a high crosslinking density, but also has low production costs;

4. The microgel structure that the emulsion obtained by the present invention has can prevent the anti-sag property, the thickness and the appearance of the coating film when the high solid content coating is applied on the vertical surface, and improve the curing speed of the coating;

5. The present invention adds alkenyl carboxylic acid monomers to obtain carboxylate-containing macromolecule segments, which can improve the stable dispersion of latex particles in water, reduce the amount of emulsifier, and improve the water resistance of the coating film.

6. The present invention introduces a divinyl unsaturated monomer as a crosslinking agent during polymerization, which overcomes the phase separation problem caused by the difference in polarity between the core and the shell.

7. In the stage of preparing the emulsion particle shell, the present invention adopts the starvation drop method, which is beneficial to the polymerization of the shell monomer on the surface of the core.

8. The emulsion polymerization obtained by the present invention has good stability and can be stored stably for more than one year.

9. The preparation method of the present invention introduces vinyl organosiloxane monomer into the core part, which undergoes hydrolysis and condensation reaction during the polymerization process to form a soft microgel structure, and the remaining unhydrolyzed and condensed siloxane is formed into a film During the process, further hydrolysis and condensation reactions occur, which not only helps to reduce the film forming temperature, but also helps to improve the adhesion between the coating film and the substrate.

10. The emulsion prepared by the present invention replaces the organic solvent with water, and the prepared emulsion is non-toxic, non-flammable and beneficial to environmental protection. The two-component water-based polyurethane prepared by using it has excellent performance and can completely replace the two-component solvent-based polyurethane coating .

11. Compared with the same kind of hydroxyl acrylic emulsion, the obtained emulsion obtained by the invention has superior water resistance, solvent resistance, abrasion resistance, heat resistance, adhesion, impact resistance and tensile properties of the obtained two-component polyurethane coating film It is widely used in water-based wood paints, exterior wall paints, water-based adhesives, fabric treatment agents, leather finishing agents, etc.

Detailed ways

Example 1-2

The monomer composition is methyl methacrylate, butyl acrylate, methacrylic acid, hydroxyethyl methacrylate, vinyl organosiloxane, triethylene glycol dimethacrylate, and its component formula is shown in Table 1:

Table 1 Composition of hydroxyacrylic emulsion with microgel core structure

Composition Example 1 Example 2

I Bottom

Deionized water 50g 124g

CO436 2.05g 5.83g

NP-9 0.40g 1.13g

II monomer mixture

Methyl methacrylate 2.8g 2.8g

Butyl acrylate 3.2g 3.2g

γ-methacryloyloxy

Propyltrimethoxysilane 1.2g 1.2g

III Initiator Solution

Potassium persulfate 0.04g 0.14g

Deionized water 5g 5g

IV drop mixture

Deionized water 36g -

CO43 0.77g -

NP-9 0.14g -

Methyl methacrylate 15g 15g

Butyl acrylate 11.7g 11.7g

Methacrylic acid 1.8g 1.8g

γ-methacryloyloxy

Propyltrimethoxysilane 0.8g 0.8g

Triethylene glycol dimethacrylate 0.3g 0.3g

V drops the mixture

Deionized water 38g -

CO436 3.01g -

NP-9 0.5gg 0.5gg -

Methyl methacrylate 35g 35g

Butyl acrylate 27.1g 27.1g

Hydroxyethyl methacrylate 12.2g 12.2g

Mercaptoethanol 0.35g 0.35g

VI initiator solution

Potassium persulfate 0.32g 0.22g

Deionized water 20g 20g

VII initiator solution

Potassium persulfate 0.04g 0.04g

Deionized water 10g 10g

NP-9 - 0.5g

VIII ammonia solution

Ammonia (28%) 8g 8g

Deionized water 5g 5g

In a 500ml four-necked bottle equipped with a thermometer, a stirring device and a condenser, add component I and raise the temperature. When the temperature in the bottle rises to 70°C, add components II and III to prepare seeds, and wait until the temperature of the system rises to 75± When the temperature is stable at 1°C, add component IV dropwise within 2 hours, then start to add component V dropwise, finish dropwise within 4 hours, and finish dropwise component VI within 6 hours. After the dropwise addition of the mixed monomers, add component VII, continue to keep warm for 1 hour and then lower the temperature. Add component VIII, adjust the pH value to 7.5-8.5, cool and filter the material, and obtain a hydroxyacrylic acid emulsion with a microgel core structure.

Example 3

The monomer composition is methyl methacrylate, butyl acrylate, methacrylic acid, hydroxyethyl methacrylate, vinyl silane coupling agent, triethylene glycol dimethacrylate, and its component formula is shown in Table 2:

Table 2 Composition of hydroxyacrylic emulsion with microgel core structure

Composition Example 3

I Bottom

Deionized water 124g

CO436 5.83g

NP-9 1.13g

II monomer mixture

Methyl methacrylate 2.8g

Butyl acrylate 2.2g

γ-methacryloxypropyl

Trimethoxysilane 1.2g

III Initiator solution

Potassium persulfate 0.04g

Deionized water 5g

IV drop the mixture

Methyl methacrylate 15g

Butyl acrylate 11.7g

Methacrylic acid 1.8g

γ-methacryloxypropyl

Trimethoxysilane 0.8g

Triethylene glycol dimethacrylate 0.3g

AIBN 0.1g

V drop the mixture

Methyl methacrylate 35g

Butyl acrylate 27.1g

Hydroxyethyl methacrylate 12.2g

Mercaptoethanol 0.35g

AIBN 0.22g

VI ammonia solution

Ammonia (28%) 8g

Deionized water 5g

In a 500ml four-necked bottle equipped with a thermometer, a stirring device and a condenser, add component I and raise the temperature. When the temperature in the bottle rises to 70°C, add components II and III to prepare seeds, and wait until the temperature of the system rises to 75± When the temperature is stable at 1°C, after adding component IV dropwise within 2 hours, start adding component V dropwise and finish dropping within 4 hours. After monomer mixing and dropwise addition, continue to keep warm for 1 hour and then cool down. Add component VI, adjust the pH value to 7.5-8.5, cool and filter the material to obtain a hydroxyacrylic acid emulsion with a microgel core structure.

Example 4

The monomer composition is methyl methacrylate, styrene, isooctyl acrylate, methacrylic acid, hydroxyethyl methacrylate, vinyl silane coupling agent, triethylene glycol dimethacrylate, and its component formula As in Table 3:

Table 3 Composition of hydroxyacrylic emulsion with microgel core structure

Composition Example 4

I Bottom

Deionized water 124g

A-102 3.42g

TX-100 2.34g

II monomer mixture

Styrene 3.7g

Isooctyl acrylate 1.3g

Vinyltriethoxysilane 1.5g

III Initiator solution

Potassium persulfate 0.04g

Deionized water 5g

IV drop the mixture

Methyl methacrylate 13g

Styrene 5g

Isooctyl acrylate 3.7g

Methacrylic acid 1.5g

Vinyltriethoxysilane 2.5g

Divinylbenzene 0.55g

AIBN 0.1g

V drop the mixture

Methyl methacrylate 25g

Styrene 19g

Isooctyl acrylate 18.1g

Hydroxyethyl acrylate 16.3g

AIBN 0.22g

VI ammonia solution

Ammonia (28%) 8g

Deionized water 5g

In a 500ml four-necked bottle equipped with a thermometer, a stirring device and a condenser, add component I and raise the temperature. When the temperature in the bottle rises to 70°C, add components II and III to prepare seeds, and wait until the temperature of the system rises to 75± When the temperature is stable at 1°C, after adding component IV dropwise within 2 hours, start adding component V dropwise and finish dropping within 4 hours. After monomer mixing and dropwise addition, continue to keep warm for 1 hour and then cool down. Add component VI, adjust the pH value to 7.5-8.5, cool and filter the material to obtain a hydroxyacrylic acid emulsion with a microgel core structure.

Example 5

Add thickener (Acrysol RM8), film-forming aid (dipropylene glycol butyl ether) and defoamer (Byk023) to the hydroxyacrylic acid emulsion in Example 1, stir at 300rpm for 15min, then add Example 2 The curing agent was stirred for 5 minutes, and an appropriate amount of water was added to adjust to the required viscosity to obtain a two-component water-based polyurethane emulsion formula composition as shown in Table 4. The pot life of the product is 3~6h, the wet film thickness is 200um, the dry film thickness is 50um, the surface dry time is 1~2h, and the dry time is 2~3h. The rheology is good.

Table 4 Two-component waterborne polyurethane formulation

Composition Mass parts

100 parts of hydroxyacrylic acid emulsion in example 1

Acrysol RM8 0.42 servings

Byk023 0.13 copies

Dipropylene glycol butyl ether 2.0 parts

Wt-2102 23 copies

Appropriate amount of water

Example 6

Add thickener (SN-612), film-forming aid (propylene glycol butyl ether) and defoamer (TEGO-805) to the hydroxyacrylic acid emulsion in Example 3, stir at 300rpm for 15min, then add solidification (VPLS2319) was stirred for 5 minutes, and an appropriate amount of water was added to adjust to the required viscosity to obtain a two-component water-based polyurethane emulsion. The formula composition is shown in Table 3. The pot life of the product is 3-6 hours, the wet film thickness is 150-200um, the dry film thickness is 40-70um, the surface dry time is 1-2h, and the dry time is 2-3h. The rheology is good.

Table 5 Two-component waterborne polyurethane formulation

Composition Mass parts

100 parts of hydroxyacrylic acid emulsion in example 3

SN-612 0.25 parts

TEGO-805 0.2 parts

Propylene glycol butyl ether 2.0 parts

VPLS2319 29 copies

Appropriate amount of water

Example 7

Add thickener (Acrysol RM8) and defoamer (Byk023) to the hydroxyacrylic acid emulsion in Example 4, stir at 300rpm for 15min, then stir with curing agent (AQ210) for 5min, add appropriate amount of water to adjust Obtain the two-component water-based polyurethane emulsion after the viscosity, and formula composition is as shown in table 6. The pot life of the product is 3-6 hours, the wet film thickness is 150-200um, the dry film thickness is 40-70um, the surface dry time is 1-2h, and the dry time is 2-3h. The rheology is good.

Table 6 two-component water-based polyurethane formula

Composition Mass parts

100 parts of hydroxyacrylic acid emulsion in example 4

Acrysol RM8 0.42 servings

Byk023 0.13 copies

AQ210 27 copies

Appropriate amount of water

Claims (7)

1, a kind of preparation method with hydroxyl acrylic emulsion of microgel nuclear structure is characterized in that comprising the steps:

(1) preparation of seed

Water, emulsifying agent are added in the reactor, add (methyl) alkyl acrylate, thiazolinyl carboxylic acid, vinyl aromatic compounds and vinyl silicane coupling agent when stirring, be warming up to 60～90 ℃, add initiator solution, reaction 20～40min, emulsion is obvious blue light and promptly gets seed emulsion;

Described each constituent mass umber is as follows:

60～130 parts in water

3～8 parts of emulsifying agents

1～10 part of (methyl) alkyl acrylate

0～5 part of thiazolinyl carboxylic acid

1～10 part of vinyl aromatic compounds

0.5～5 part of vinyl silicane coupling agent

2～6 parts of initiator solutions (concentration is 1% quality);

(2) He preparation

Mixture with (methyl) alkyl acrylate, vinyl aromatic compounds, vinyl silicane coupling agent, thiazolinyl carboxylic acid, diethyl ethylenically unsaturated monomers, water, emulsifying agent, and initiator solution, splash into simultaneously respectively in 1～3h in the seed emulsion that (1) obtain, temperature of reaction maintains 60～90 ℃ hours;

Described each constituent mass umber is as follows:

0～60 part in water

0～3 part of emulsifying agent

20～80 parts of (methyl) alkyl acrylates

0～5 part of thiazolinyl carboxylic acid

1～10 part of vinyl aromatic compounds

0.5～5 part of vinyl silicane coupling agent

0.1～2 part of divinyl base class unsaturated monomer

0～40 part of initiator solution (concentration is 1% quality);

(3) preparation of shell

Mixture with (methyl) alkyl acrylate, (methyl) acrylic acid hydroxy alkyl ester, vinyl aromatic compounds, thiazolinyl carboxylic acid, water, emulsifying agent, and initiator solution, in 2～5 hours, splash in the reactor simultaneously respectively, temperature of reaction maintains 60～90 ℃, reaction finishes insulation 1～2 hour, promptly gets solid content and be 30～50% the hydroxyl acrylic emulsion with microgel nuclear structure; Described each constituent mass umber is as follows:

0～60 part in water

0～3 part of emulsifying agent

20～80 parts of (methyl) alkyl acrylates

10～30 parts of (methyl) acrylic acid hydroxy alkyl esters

0.5～5 part of thiazolinyl carboxylic acid

1～10 part of vinyl aromatic compounds

0～40 part of initiator solution (concentration is 1% quality);

The alkyl carbon atoms number of described (methyl) alkyl acrylate is C1～C15; The alkyl carbon atoms number of described (methyl) acrylic acid hydroxy alkyl ester is C1～C15; The alkyl carbon atoms number of described thiazolinyl carboxylic acid is C1～C15; Described vinyl aromatic compounds is vinylbenzene, alpha-methyl styrene, 2-chlorostyrene, 3-t-butyl styrene, 3, one or more mixtures in the 4-dimethyl styrene; Described vinyl silicane coupling agent is one or more mixtures in vinyltrimethoxy silane, vinyl methoxyl group diethoxy silane, vinyltriethoxysilane, vinyl oxyethyl group diisopropoxy silane, vinyl silane triisopropoxide, γ-methacryloxypropyl trimethoxy silane, the γ-methacryloxypropyl three isopropoxy silane; Described divinyl base class unsaturated monomer is one or more mixtures in Vinylstyrene, Ethylene glycol dimethacrylate, dimethacrylate triglycol ester, TriMethylolPropane(TMP) methacrylic ester, the dimethacrylate TEG ester; Described initiator is Potassium Persulphate or ammonium persulphate; Described emulsifying agent is the mixture of anionic emulsifier and nonionic emulsifying agent.

2, the preparation method with hydroxyl acrylic emulsion of microgel nuclear structure according to claim 1 is characterized in that described (methyl) alkyl acrylate is one or more mixtures in methyl methacrylate, Jia Jibingxisuanyizhi, butyl methacrylate, methacrylic acid pentyl ester, N-Hexyl methacrylate, n octyl methacrylate, Isooctyl methacrylate, methyl acrylate, ethyl propenoate, butyl acrylate, vinylformic acid pentyl ester, Ethyl acrylate, vinylformic acid n-octyl, the Isooctyl acrylate monomer.

3, the preparation method with hydroxyl acrylic emulsion of microgel nuclear structure according to claim 1 is characterized in that described (methyl) acrylic acid hydroxy alkyl ester is one or more mixtures in vinylformic acid-2-hydroxyl ethyl ester, vinylformic acid-3-hydroxypropyl acrylate, vinylformic acid-2-hydroxy butyl ester, vinylformic acid-5-hydroxy pentane ester, the vinylformic acid-own ester of 6-hydroxyl, 2-hydroxyethyl methacrylate, the methacrylic acid-2-hydroxypropyl acrylate.

4, the preparation method with hydroxyl acrylic emulsion of microgel nuclear structure according to claim 1 is characterized in that described thiazolinyl carboxylic acid is one or more mixtures in vinylformic acid, methacrylic acid, the methylene-succinic acid.

5, the preparation method with hydroxyl acrylic emulsion of microgel nuclear structure according to claim 1 is characterized in that described anionic emulsifier is one or more mixtures in sodium lauryl sulphate, Sodium dodecylbenzene sulfonate, alkyl diphenyl ether disodium sulfonate salt, oxyethyl group disodium sulfosuccinate, sodium vinyl sulfonate, oxyethyl group phenolic ether sodium sulfate, alkyl amido sodium vinyl sulfonate, allyl ethers hydroxyl sulfoacid sodium, the phenolic ether phosphoric acid ester; Nonionic emulsifying agent is one or more mixtures in the poly-ethoxy Vinyl Ether of fatty alcohol-polyoxyethylene ether, nonyl phenol, polyoxyethylene octylphenol ether, oxyethyl group propoxy-edge section Fatty Alcohol(C12-C14 and C12-C18), the Isosorbide Dinitrate.

6, the hydroxyl acrylic emulsion with microgel nuclear structure of the described method preparation of claim 1.

7, the described hydroxyl acrylic emulsion with microgel nuclear structure of claim 6 is used to prepare the method for dual-component aqueous polyurethane, it is characterized in that comprising the steps:

(1) above-mentioned hydroxyl acrylic emulsion is joined stirring tank, under 200～1000rpm agitation condition, film coalescence aid, defoamer and thickening material are slowly joined in the hydroxyl acrylic emulsion, stir 10～30min;

(2) the hydrophilically modified polyisocyanates solidifying agent is slowly joined in the hydroxyl acrylic emulsion, add entry behind stirring 5～15min and reach working viscosity;

Described each constituent mass umber is as follows:

100 parts of hydroxyl acrylic emulsions with microgel nuclear structure

10～40 parts in solidifying agent

0～5 part of film coalescence aid

0.05～0.5 part of defoamer

0.1～1 part of thickening material

Described solidifying agent is the polyisocyanates of nonionic polyethers and/or anionic hydrophilic modification; One or more mixtures in described film coalescence aid ethylene glycol ethyl ether, ethylene glycol monobutyl ether, Diethylene Glycol butyl ether, propylene glycol monomethyl ether, propylene glycol monobutyl ether, the dipropylene glycol methyl ether; Described thickening material is one or more the mixture among Natvosol, RM-2020, the SN-612.