CN114016299B - Preparation method of VAE coating for imitating artificial PU - Google Patents

Abstract

The invention relates to the technical field of coating compositions, and discloses a VAE coating for imitation PU and a preparation method thereof, wherein the coating comprises the following components in parts by weight: 30-60 parts of vinyl acetate-ethylene copolymer emulsion; 20-40 parts of titanium dioxide; 5-20 parts of quartz powder; 5-20 parts of plasticizer; 3-5 parts of wetting agent; 3-5 parts of defoamer. The coating disclosed by the invention has the advantages of strong binding power, good elasticity, good flexibility, soft hand feeling, anti-back adhesion, low cost, safety, environment friendliness, no toxicity, no smell, easiness in degradation, no pollution and no harm to human bodies.

Description

Preparation method of VAE coating for imitating artificial PU

Technical field

This case is a divisional application. The application number of the parent case is: 2021112174555. The invention and creation name of the parent case is: VAE coating for imitating artificial PU and its preparation method. The applicants of the parent case are: China Petroleum & Chemical Corporation, China Petrochemical Group Chongqing Chuanwei Chemical Co., Ltd. and Chongqing Chuanwei Technology Co., Ltd., the application date of the parent case is: October 19, 2021, and the application type of the parent case is: invention patent.

The invention relates to the technical field of coating compositions, and in particular to a VAE coating for imitating artificial PU and a preparation method thereof.

Background technique

PU is the abbreviation of Polyurethane. The Chinese name is polyurethane, which is abbreviated as polyurethane. Because it only needs to simply modify the formula, different physical properties such as density, elasticity, and rigidity can be obtained. Currently, it is widely used in interior and exterior wall insulation materials, refrigerators, etc. Insulation materials, home decoration, high-end sporting goods and synthetic PU leather and other fields.

However, due to the high cost of synthetic PU leather, it is difficult to promote it on a large scale in some soft bag fields. In existing artificial PU leather-like coatings, in order to increase the flexibility and feel of the coating film, the emulsion content as the base material in the coating will be increased. Adding too much emulsion will cause the coating to have a certain degree of stickiness. Tackiness refers to the phenomenon that the paint film adheres due to the influence of a certain temperature and humidity after it dries, and it appears sticky. Once the coating film sticks back, it is easy to stick to dust, which affects the decorative properties of the coating film. Moreover, the coating film's sticking back is accompanied by the softening of the coating film, which will reduce the hardness, wear resistance and corrosion resistance of the coating film. The sticky coating can only be scraped off and recoated. Therefore, the sticky coating is a coating defect. In order to solve the problem of coating film stickiness, the general approach is to reduce the emulsion content as the base material in the coating, thereby improving the coating film's resistance to stickiness. However, new problems arise at this time, because the emulsion as the base material in the coating The emulsion content of the material is reduced, and the paint will easily fall off after spraying.

Therefore, how to prepare a coating that has anti-stickiness and is not easy to fall off is a technical problem that needs to be solved urgently in the existing technology.

Contents of the invention

The present invention is intended to provide a VAE coating for imitating artificial PU and a preparation method thereof, so that the prepared coating has anti-stickiness and is not prone to powder falling off problems.

In order to achieve the above objects, the present invention adopts the following technical solutions:

A VAE coating for imitating artificial PU, including the following components by weight:

The principle and advantage of this solution are: the non-ionic wetting agent can evenly disperse the filler in the emulsion, thereby making the coating have excellent anti-sticking properties.

In practical applications, emulsions play a decisive role in the mechanical and thermal properties of coatings. During the film formation process, the emulsion particles come close to each other and agglomerate, and bind the pigments and fillers to form a continuous coating film. The addition of emulsion will improve the mechanical properties of the coating, such as adhesion, elongation at break and flexibility; but at the same time, the increase in emulsion content will reduce the anti-sticking properties of the coating film. Therefore, in order to avoid this problem in the prior art, the method usually adopted is to moderately reduce the content of the emulsion. However, this method has the disadvantage that the powder is easy to fall off after the coating forms a film. This application, by screening a variety of different pigments, fillers and related additives without reducing the content of the emulsion, unexpectedly found a synergistic effect between the wetting agent and quartz powder. Wetting agents have the function of reducing the surface tension of the coating, allowing the coating to better wet the substrate, and are generally used to improve the adhesion of the coating to the substrate. Quartz powder is a filler, consisting of silica. It is generally used to fill paints to reduce paint costs; it can also improve the wear resistance, heat resistance and chemical resistance of paints. In addition, during the research process, the inventor unexpectedly discovered that after quartz powder and wetting agent were added to the coating through compounding, it not only maintained the original effect, but also effectively improved the anti-stickiness of the coating film. , to overcome the problem of paint powder falling off. The mechanism is: the wetting agent is used to reduce the surface tension of the emulsion, so that the quartz powder is evenly dispersed in the system. After the film is dried, the adhesive force of the latex and the hardness of the quartz powder distributed on the surface of the latex are fully utilized.

In addition to the above properties, the coating of the present invention also has strong adhesion, high strength, good flexibility, soft hand feel, low cost, non-toxic, tasteless, easy to degrade, non-polluting, safe and environmentally friendly, and harmless to the human body. advantage.

Preferably, as an improvement, the ethylene content in the vinyl acetate-ethylene copolymer emulsion is ≥25%.

Beneficial effects: When the ethylene content is within this range, the coating has a lower minimum film-forming temperature and better elasticity and flexibility. If the ethylene content is lower than this range, the glass transition temperature of the coating will increase, causing the minimum film forming temperature to increase. If the minimum film-forming temperature is higher than normal temperature, the coating cannot form a film. In this case, the low-temperature moldability can only be ensured by adding additional film-forming additives. Excessive addition of film-forming additives will affect the coating film. With excellent water and alcohol resistance, the actual drying speed will also be extended. In addition, an increase in the glass transition temperature of the coating will also reduce the elasticity and flexibility of the coating.

Preferably, as an improvement, the particle size of titanium dioxide is 600-1250 mesh.

Beneficial effects: When the particle size of titanium dioxide is within this range, titanium dioxide has good dispersion, which can make titanium dioxide more evenly distributed in the emulsion, have better compatibility with the emulsion, and can enhance the strength and adhesion of the coating film. force. If the particle size of titanium dioxide is too large, the titanium dioxide will not be evenly distributed in the emulsion; if the particle size of titanium dioxide is too small, the strength and adhesion of the coating film will be reduced, and the life of the paint film will be shortened.

Preferably, as an improvement, the particle size of quartz powder is 600-1250 mesh.

Beneficial effects: The particle size of quartz powder is within this range, so that the quartz powder can be evenly dispersed throughout the entire paint coating when the paint film is formed, which can significantly improve the strength of the paint film. If the particle size of quartz powder is too large, the quartz powder will not be easily distributed evenly in the coating; if the particle size of quartz powder is too small, the strength of the coating will be reduced. The synergistic effect of quartz powder and wetting agents can improve the anti-sticking performance of the coating film.

Preferably, as an improvement, the plasticizer is one of MADE and TXIB.

Beneficial effects: MADE and TXIB are non-toxic and environmentally friendly plasticizers, which can significantly increase the strength and elasticity of the coating film, and improve flexibility and adhesion.

MADE (called DBE by DuPont) is a mixture of dibasic acid esters, also known as divalent acid esters. It is an environmentally friendly high boiling point solvent with low toxicity, low odor, and biodegradability. Omode MADE series products include dimethyl succinate, dimethyl glutarate, dimethyl adipate and their mixtures in different proportions. The concentrations of each component in the mixture are: dimethyl glutarate 25 -60%, dimethyl adipate 20-50%, dimethyl succinate 10-30%.

The chemical name of TXIB is 2,2,4-trimethyl 1,3-pentanediol diisobutyrate. It is a viscosity reducer with plasticizing effect and low volatility, which can give the coating good cold resistance. and water resistance.

Preferably, as an improvement, the wetting agent is a nonionic wetting agent.

Beneficial effects: Non-ionic wetting agents can better reduce the surface tension of the coating, have better hydrophilicity, quickly wet the base material, and improve the adhesion of the coating. Nonionic wetting agents work synergistically with fillers to improve the anti-sticking properties of coatings.

As a type of wetting agent, nonionic wetting agents include polyoxyethylene alkyl phenol ethers, polyoxyethylene fatty alcohol ethers, polyoxyethylene polyoxypropylene block copolymers, etc., which are well known to those skilled in the art.

Preferably, as an improvement, the defoaming agent is one or both of block polyether defoaming agents and organosiloxane defoaming agents.

Beneficial effects: Blocked polyether defoaming agents and organosiloxane defoaming agents have both good defoaming and foam suppressing effects, good stability, non-toxic, and environmentally friendly.

On the other hand, the present invention also provides a preparation method of VAE coating for artificial PU, which includes the following steps: combining vinyl acetate-ethylene copolymer emulsion, titanium dioxide, quartz powder, plasticizer, wetting agent and defoaming agent Mix, stir well and let sit.

Beneficial effects: Through mechanical stirring, the ingredients in the paint can be mixed evenly, so that the formed coating film is more uniform, smoother and fuller in color; and the preparation method is simple and conducive to industrial production.

Preferably, as an improvement, the stirring speed is 600-1800 rpm and the standing time is 60-90 minutes.

Beneficial effects: The coating is dispersed more evenly within this stirring speed range; if the stirring speed is too low, the components in the emulsion will be unevenly dispersed; if the stirring speed is too high, the emulsion will break. Letting it sit for a period of time can allow the bubbles in the paint to fully escape, and make the components in the paint dissolve better with each other and mix more evenly.

In yet another aspect, the present invention provides an application of a VAE coating for imitating artificial PU in preparing imitation artificial PU, artificial fibers and as a binder for cotton fabrics.

Beneficial effects: The coating of this application can be used to manufacture imitation artificial PU, artificial fibers and for bonding cotton fabrics.

Detailed ways

The following is further detailed through specific implementation methods:

VAE emulsion CW40-602 was purchased from Sinopec Group Chongqing Chuanwei Chemical Co., Ltd.; ST-83 was purchased from Solvay; MP200 was purchased from Momentive, and Omod MADE was purchased from Jiangsu Omod Paint Co., Ltd.

Example 1 Preparation of artificial VAE coating

The artificial artificial VAE coating consists of:

VAE emulsion: 300g VAE emulsion CW40-602 (ethylene content is 25%);

Titanium dioxide: 400g, particle size 800 mesh;

Quartz powder: 200g, particle size 800 mesh;

Plasticizer: 100g, the plasticizer in this example is MADE;

Wetting agent: 50g, the wetting agent in this example is ST-83;

Defoaming agent: 50g. The defoaming agent in this example is MP200.

The preparation method of the above artificial VAE coating is:

Mix the above vinyl acetate-ethylene copolymer emulsion, titanium dioxide, quartz powder, MADE, ST-83 and MP200 evenly; then stir and disperse evenly at 900 rpm and let stand for 90 minutes.

Example 2 Preparation of artificial VAE coating

The artificial artificial VAE coating consists of:

VAE emulsion: 300g VAE emulsion CW40-602 (ethylene content is 25%);

Titanium dioxide: 300g, particle size 800 mesh;

Quartz powder: 200g, particle size 800 mesh;

Plasticizer: 150g TXIB;

Wetting agent: 30g ST-83;

Defoaming agent: 30g MP200.

The preparation method of the coating is:

Mix the above vinyl acetate-ethylene copolymer emulsion, titanium dioxide, quartz powder, TXIB, ST-83 and MP200 evenly; then stir and disperse evenly at 600 rpm and let stand for 60 minutes.

Example 3 Preparation of artificial VAE coating

The artificial artificial VAE coating consists of:

VAE emulsion: 400g VAE emulsion CW40-602 (ethylene content is 30%);

Titanium dioxide: 400g particle size 800 mesh;

Quartz powder: 100g particle size 800 mesh;

Plasticizer: 200g MADE;

Wetting agent: 30g ST-83;

Defoaming agent: 20g MP200.

The preparation method of the coating is:

Mix the above vinyl acetate-ethylene copolymer emulsion, titanium dioxide, quartz powder, high boiling point plasticizer, wetting agent and defoaming agent evenly; then stir and disperse evenly at 1800 rpm and let stand for 90 minutes.

Example 4 Preparation of artificial VAE coating

The artificial artificial VAE coating consists of:

VAE emulsion: 500g VAE emulsion CW40-602 (ethylene content is 25%);

Titanium dioxide: 200g, particle size 800 mesh;

Quartz powder: 50g, particle size 800 mesh;

High boiling point plasticizer: 150g TXIB;

Wetting agent: 30g ST-83;

Defoaming agent: 20g MP200.

The preparation method of the coating is:

Mix the above vinyl acetate-ethylene copolymer emulsion, titanium dioxide, quartz powder, high boiling point plasticizer, wetting agent and defoaming agent evenly; then stir and disperse evenly at 1200 rpm and let stand for 80 minutes.

Example 5 Preparation of artificial VAE coating

The artificial artificial VAE coating consists of:

VAE emulsion: 600g VAE emulsion CW40-602 (ethylene content is 25%);

Titanium dioxide: 200g, particle size 800 mesh;

Quartz powder: 100g, particle size 800 mesh;

High boiling point plasticizer: 50g TXIB;

Wetting agent: 30g ST-83;

Defoaming agent: 20g MP200.

The coating preparation method is:

Mix the above vinyl acetate-ethylene copolymer emulsion, titanium dioxide, quartz powder, high boiling point plasticizer, wetting agent and defoaming agent evenly; then stir and disperse evenly at 1000 rpm and let stand for 75 minutes.

Comparative example 1

The difference between this comparative example and Example 1 is that no quartz powder is added.

Comparative example 2

The difference between this comparative example and Example 1 is that ST-83 was not added.

Comparative example 3

The difference between this comparative example and Example 1 is that quartz powder and ST-83 were not added.

Application performance testing

The coatings prepared in Examples 1-5 and Comparative Examples 1-12 were used to make imitation PU, and then dried at 110°C for 5 minutes, and then maintained at room temperature for 24 hours, and part of the material was taken out to make 2 cm wide* 10 cm long strip-shaped adhesive material, each example is set to 10 repetitions, and the C43 microcomputer-controlled universal testing machine produced by MTS in the United States is used to test the peeling tensile strength of the imitation PU material, and the average value is used as the test result. The above groups Except for the different coatings, other conditions are the same, and the results are shown in Table 1.

Table 1 Performance test results

Group Peel tensile strength/MPa Example 1 Broken material Example 2 Broken material Example 3 Broken material Example 4 Broken material Example 5 Broken material Comparative example 1 Easier to peel off Comparative example 2 Easier to peel off Comparative example 3 Easy to peel off

The results show: It can be seen from Table 1 that the coatings of Examples 1-5 are used to produce imitation PU and damage the base material. This proves that the adhesive of the present invention has strong bonding force. In addition, the coatings of Examples 1-5 have no pungent odor. This proves that the coating of the present invention is safe and environmentally friendly. Moreover, the coatings prepared in Examples 1-5 basically had no back-sticking problem, while Comparative Examples 1-3 showed varying degrees of back-sticking.

The above are only embodiments of the present invention, and common knowledge such as specific technical solutions and/or characteristics that are known in the scheme are not described in detail here. It should be pointed out that for those skilled in the art, several modifications and improvements can be made without departing from the technical solution of the present invention. These should also be regarded as the protection scope of the present invention and will not affect the implementation of the present invention. The effect and practicality of the patent. The scope of protection claimed in this application shall be based on the content of the claims, and the specific implementation modes and other records in the description may be used to interpret the content of the claims.

Claims (2)

1. A preparation method of a VAE coating for imitation PU is characterized by comprising the following steps: the method comprises the following steps: mixing vinyl acetate-ethylene copolymer emulsion, titanium dioxide, quartz powder, plasticizer, wetting agent and defoamer, stirring uniformly, and standing;

the VAE coating comprises the following components in parts by weight:

30-60 parts of vinyl acetate-ethylene copolymer emulsion;

20-40 parts of titanium dioxide;

5-20 parts of quartz powder;

5-20 parts of high boiling point solvent;

3-5 parts of wetting agent;

3-5 parts of a defoaming agent;

the particle size of the titanium dioxide is 600-1250 meshes, the plasticizer is one of European MADE and TXIB, and the wetting agent is a nonionic wetting agent; the ethylene content in the vinyl acetate-ethylene copolymer emulsion is more than or equal to 25 percent.

2. The method for preparing the VAE coating for the imitation PU according to claim 1, wherein the method comprises the following steps: the stirring speed is 600-1800 rpm, and the standing time is 60-90 minutes.