An environmentally friendly coating based on EEP and preparation method thereof

Abstract

The present invention relates to an environmentally friendly coating based on EEP, wherein the environmentally friendly coating based on EEP comprises the following components by mass: 60-80 parts of organic resin, 10-20 parts of modified polyvinyl alcohol, 1-10 parts of modifier, 10-20 parts of filler, 1-10 parts of auxiliary agent, 30-50 parts of EEP, and water; wherein the modified polyvinyl alcohol is polyvinyl alcohol modified by a silane coupling agent; and the modifier is a silane polymer. The present invention adopts an organic resin as a base resin, and is compounded with components such as polyvinyl alcohol modified by a silane coupling agent, a silane polymer modifier, and a filler, and adopts a new environmentally friendly solvent EEP (ethyl 3-ethoxypropionate) to replace a traditional organic solvent, and the compatibility between multiple components is good, while ensuring the stability of the coating product, the mechanical strength and self-cleaning performance are effectively improved, and the shortcomings in the prior art are overcome.

Description

Technical Field

[0001] The present invention relates to the technical field of coatings, and in particular to an environmentally friendly coating based on EEP and a preparation method thereof. Background Art

[0002] In order to prevent rust and corrosion, metal devices are usually coated with paint on the surface, which forms a paint film after curing, thereby achieving a protective effect. It also has important decorative and beautifying functions.

[0003] However, paint products often contain highly polluting raw materials, such as toluene and xylene. These volatile organic solvents not only damage the atmospheric ecological environment, but are also carcinogens and may cause harm to human health, so they pose a greater risk.

[0004] With the continuous progress of society and the increasing demand for environmental protection in the market, the use of volatile toxic solvents and additives in coating products has been gradually reduced. However, due to the continuous improvement of protection requirements and the continuous increase of specific needs, the strength, adhesion and self-cleaning properties of conventional existing coatings can no longer meet the needs of the industry and have many defects.

[0005] In summary, it is urgent to develop a new technical solution to solve the problems existing in the prior art. Summary of the invention

[0006] Based on this, the present invention has developed an environmentally friendly coating based on EEP and a preparation method thereof. The present invention uses an organic resin as a base resin, compounded with silane coupling agent modified polyvinyl alcohol, silane polymer modifier, filler and other components, and uses a new environmentally friendly solvent EEP (ethyl 3-ethoxypropionate) to replace the traditional organic solvent. The compatibility between the various components is good, while ensuring the stability of the coating product, the mechanical strength and self-cleaning performance are effectively improved, and the shortcomings existing in the prior art are overcome.

[0007] One object of the present invention is to provide an environmentally friendly coating based on EEP, wherein the environmentally friendly coating based on EEP comprises the following components in parts by weight:

[0008]

[0009] water;

[0010] in,

[0011] The modified polyvinyl alcohol is polyvinyl alcohol modified by a silane coupling agent;

[0012] The modifier is a silane polymer.

[0013] Furthermore, the silane coupling agent is selected from one or more of aminosilane coupling agents and epoxysilane coupling agents.

[0014] Furthermore, the polymerization monomer of the silane polymer is alkyl silicate.

[0015] Furthermore, the auxiliary agent is selected from one or more of a wetting agent, a leveling agent, a defoaming agent, an emulsifier, a dispersant, a pH regulator, a photoinitiator, and a curing agent.

[0016] Furthermore, the organic resin includes water-based polyester resin and bisphenol epoxy acrylic resin.

[0017] Another object of the present invention is to provide a method for preparing the above-mentioned environmentally friendly coating based on EEP, comprising the following steps:

[0018] S1, adding alkyl silicate to a solvent, then adding a catalyst and water, stirring and heating to react, and purifying to obtain a modifier;

[0019] S2, adding a silane coupling agent to an aqueous solution of polyvinyl alcohol, heating the solution under alkaline conditions for reaction, and purifying the solution to obtain modified polyvinyl alcohol;

[0020] S3, blending the modifier, modified polyvinyl alcohol, organic resin, filler, additive, EEP and water, stirring evenly, discharging, and obtaining a product.

[0021] Furthermore, in step S1, the stirring and heating reaction is carried out at a temperature of 50-70°C and for a time of 2-5 hours.

[0022] Furthermore, in step S1, the catalyst is an acid catalyst.

[0023] Furthermore, in step S2, the heating reaction temperature is 50-80°C and the time is 2-5h.

[0024] Furthermore, in step S2, the pH of the alkaline condition is 9-11.

[0025] The present invention has the following beneficial effects:

[0026] 1. The environmentally friendly coating based on EEP provided by the present invention uses water-based polyester resin and bisphenol epoxy acrylic resin as base resins, and uses modified polyvinyl alcohol and modifiers as components. The modified polyvinyl alcohol is obtained by reacting the active groups (such as epoxy groups) in the silane coupling agent with the hydroxyl groups in the polyvinyl alcohol molecules. The branched structure and highly active silanol groups are introduced into the modified polyvinyl alcohol, which is beneficial to improving the compatibility between various components. At the same time, it has strong polarity and can enhance adhesion and stability. The modifier is obtained by polymerization of small molecular alkyl silicate, has a higher density and a higher content of siloxy groups, can promote crosslinking, enhance stability, and also has a hydrophilic effect. The present invention uses modified polyvinyl alcohol and a modifier as components, which can produce good synergistic effects. On the one hand, it has good compatibility with components such as a base resin, can form a stable three-dimensional network structure through cross-linking between active groups, and can also generate intermolecular forces with silica fillers with hydroxyl groups on the surface, thereby enhancing stability and mechanical strength; on the other hand, the large number of polar groups introduced significantly improve the hydrophilicity of the coating, can promote the coating to absorb external moisture to form a water film, thereby enhancing the anti-fouling and self-cleaning effects of the coating, and meeting the market demand for product performance.

[0027] 2. The present invention adopts EEP as a solvent. Compared with traditional organic solvents, EEP has groups such as propionyl, ester, and ether bonds. It not only has lower volatility, but also has stronger compatibility with other components, which is beneficial to improving product stability, and does not have the risk of environmental pollution. It is greener and more environmentally friendly. DETAILED DESCRIPTION

[0028] In order to more clearly illustrate the technical solution of the present invention, the following examples are listed. Unless otherwise stated, the raw materials, reactions and post-treatment methods shown in the examples are common raw materials on the market and technical methods well known to those skilled in the art.

[0029] The words "preferred", "preferably", "more preferably", etc. in the present invention refer to embodiments of the present invention that can provide certain beneficial effects in certain circumstances. However, other embodiments may also be preferred under the same circumstances or other circumstances. In addition, the description of one or more preferred embodiments does not imply that other embodiments are not applicable, nor is it intended to exclude other embodiments from the scope of the present invention.

[0030] It should be understood that, except in any operating examples, or where otherwise indicated, all numbers indicating, for example, the amounts of ingredients used in the specification and claims should be understood to be modified in all cases by the term "about". Therefore, unless indicated to the contrary, the numerical parameters set forth in the following specification and the appended claims are approximate values ​​that vary depending on the desired properties to be obtained by the present invention.

[0031] The organic resin in the embodiment of the present invention is a water-based polyester resin ( -4200-80) and bisphenol A epoxy acrylate resin (Sanmu 6105-80Y).

[0032] The polyvinyl alcohol in the embodiment of the present invention is Shanghai Yingjia PVA0588.

[0033] The filler in the embodiment of the present invention is nano silicon dioxide with a particle size of 10-20 nm.

[0034] The auxiliary agents in the embodiment of the present invention are hydroxypropyl cellulose, photoinitiator 2959, curing agent MHG-80B and emulsifier methacryloyloxyethyl dodecyl dimethyl ammonium bromide in a mass ratio of 1:1:1:1.

[0035] The "parts" in the embodiments of the present invention refer to parts by mass.

[0036] Example 1

[0037] An environmentally friendly coating based on EEP, comprising the following components in parts by weight:

[0038]

[0039] The preparation method of the EEP-containing composition comprises the following steps:

[0040] S1. Using ethanol as solvent, ethyl silicate was added, and then deionized water (ethyl silicate: deionized water = 1:1, n / n) was added under stirring, and the pH was adjusted to 4 with 15 wt % hydrochloric acid, and the reaction was stirred at 60° C. for 4 h. After removing the solvent by distillation under reduced pressure, a modifier was obtained;

[0041] S2, adding 10 g of polyvinyl alcohol to 90 mL of deionized water, stirring at 90° C. for 2 h to obtain an aqueous solution of polyvinyl alcohol;

[0042] 2 g of KH560 was added to the aqueous solution of polyvinyl alcohol, the pH was adjusted to 10 with 10 wt % sodium hydroxide solution, the reaction was carried out at 60° C. for 2 h, the pH was then adjusted to 12, and the modified polyvinyl alcohol was obtained by centrifugation, washing and drying;

[0043] S3. According to the above mass fractions, the modifier, modified polyvinyl alcohol, organic resin, filler, additive, EEP and water are mixed, stirred evenly, and discharged to obtain a product.

[0044] Example 2

[0045] An environmentally friendly coating based on EEP, comprising the following components in parts by weight:

[0046]

[0047] The preparation method of the EEP-containing composition comprises the following steps:

[0048] S1. Using ethanol as solvent, ethyl silicate was added, and then deionized water (ethyl silicate: deionized water = 1:1, n / n) was added under stirring, and the pH was adjusted to 4 with 15 wt % hydrochloric acid, and the reaction was stirred at 60° C. for 4 h. After removing the solvent by distillation under reduced pressure, a modifier was obtained;

[0049] S2, adding 10 g of polyvinyl alcohol to 90 mL of deionized water, stirring at 90° C. for 2 h to obtain an aqueous solution of polyvinyl alcohol;

[0050] 2 g of KH560 was added to the aqueous solution of polyvinyl alcohol, the pH was adjusted to 10 with 10 wt % sodium hydroxide solution, the reaction was carried out at 60° C. for 2 h, the pH was then adjusted to 12, and the modified polyvinyl alcohol was obtained by centrifugation, washing and drying;

[0051] S3. According to the above mass fractions, the modifier, modified polyvinyl alcohol, organic resin, filler, additive, EEP and water are mixed, stirred evenly, and discharged to obtain a product.

[0052] Example 3

[0053] An environmentally friendly coating based on EEP, comprising the following components in parts by weight:

[0054]

[0055]

[0056] The preparation method of the EEP-containing composition comprises the following steps:

[0057] S1. Using ethanol as solvent, ethyl silicate was added, and then deionized water (ethyl silicate: deionized water = 1:1, n / n) was added under stirring, and the pH was adjusted to 4 with 15 wt % hydrochloric acid, and the reaction was stirred at 60° C. for 4 h. After removing the solvent by distillation under reduced pressure, a modifier was obtained;

[0058] S2, adding 10 g of polyvinyl alcohol to 90 mL of deionized water, stirring at 90° C. for 2 h to obtain an aqueous solution of polyvinyl alcohol;

[0059] 2 g of KH560 was added to the aqueous solution of polyvinyl alcohol, the pH was adjusted to 10 with 10 wt % sodium hydroxide solution, the reaction was carried out at 60° C. for 2 h, the pH was then adjusted to 12, and the modified polyvinyl alcohol was obtained by centrifugation, washing and drying;

[0060] S3. According to the above mass fractions, the modifier, modified polyvinyl alcohol, organic resin, filler, additive, EEP and water are mixed, stirred evenly, and discharged to obtain a product.

[0061] Comparative Example 1

[0062] A coating, the difference between this comparative example and Example 1 is that the modified polyvinyl alcohol is replaced by unmodified polyvinyl alcohol in equal parts by mass, and the other ingredients and preparation method are the same as those in Example 1.

[0063] Comparative Example 2

[0064] A coating, the difference between this comparative example and Example 1 is that the modifier is replaced by ethyl silicate in equal parts by mass, and the other ingredients and preparation method are the same as those in Example 1.

[0065] Test Case

[0066] The coating samples prepared in Examples 1-3 and Comparative Examples 1-2 were subjected to performance tests.

[0067] The coating samples prepared in Examples 1-3 and Comparative Examples 1-2 were coated on the surface of a metal substrate of 100 mm×100 mm, and a coating layer of 5 μm thickness was obtained after curing.

[0068] Test method:

[0069] The performance test is carried out in accordance with HG / T 3830-2006, GB / T 9286, GB / T 9780 and other standards.

[0070] The test results are shown in Table 1.

[0071] Table 1 Performance test results

[0072]

[0073]

[0074] According to Table 1, it can be concluded that the environmentally friendly coating based on EEP prepared in the embodiment of the present invention has good adhesion, strong stability, excellent acid resistance and salt spray resistance, and has certain self-cleaning performance and good stain resistance. However, the comparative examples 1-2 in which the modified polyvinyl alcohol or the modifier is replaced cannot obtain the desired performance improvement, and many performances of the product are significantly reduced, and the appearance has blistering, cracking, rust spots, etc. In summary, the present invention overcomes the defects of existing products and has good application prospects.

[0075] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be considered exemplary and non-restrictive in all respects, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims be included in the present invention.

[0076] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. An environmentally friendly coating based on EEP, characterized in that: The EEP-based environmentally friendly coating comprises the following components in parts by weight: in, The modified polyvinyl alcohol is polyvinyl alcohol modified by a silane coupling agent; The modifier is a silane polymer; The filler is nano silicon dioxide with a particle size of 10-20nm; The silane coupling agent is selected from one or more of aminosilane coupling agents and epoxysilane coupling agents; The polymerization monomer of the silane polymer is alkyl silicate; The organic resin is a water-based polyester resin and a bisphenol A epoxy acrylic resin in a mass ratio of 3:

1.

2. The environmentally friendly coating based on EEP according to claim 1, characterized in that: The auxiliary agent is selected from one or more of a wetting agent, a leveling agent, a defoaming agent, an emulsifier, a dispersant, a pH regulator, a photoinitiator, and a curing agent.

3. The method for preparing the environmentally friendly coating based on EEP according to any one of claims 1 to 2, characterized in that: The steps include: S1, adding alkyl silicate to a solvent, then adding a catalyst and water, stirring and heating to react, and purifying to obtain a modifier; S2, adding a silane coupling agent to an aqueous solution of polyvinyl alcohol, heating the solution under alkaline conditions for reaction, and purifying the solution to obtain modified polyvinyl alcohol; S3, blending the modifier, modified polyvinyl alcohol, organic resin, filler, additive, EEP and water, stirring evenly, discharging, and obtaining a product.

4. The method for preparing the environmentally friendly coating based on EEP according to claim 3, characterized in that: In step S1, the stirring and heating reaction is carried out at a temperature of 50-70°C and for a time of 2-5 hours.

5. The method for preparing the environmentally friendly coating based on EEP according to claim 3, characterized in that: In step S1, the catalyst is an acid catalyst.

6. The method for preparing the environmentally friendly coating based on EEP according to claim 3, characterized in that: In step S2, the heating reaction temperature is 50-80°C and the time is 2-5h.

7. The method for preparing the environmentally friendly coating based on EEP according to claim 3, characterized in that: In step S2, the pH of the alkaline condition is 9-11.

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