Yellowing-resistant coating for cement-based floor overlay and use method of yellowing-resistant coating

Abstract

The invention discloses a coating for an anti-yellowing cement base floor overlay and a use method thereof, the coating for the floor overlay comprises an isocyanate curing agent component and a resin component, the isocyanate curing agent component is composed of an adduct prepared by reaction of isophorone diisocyanate (IPDI) and 2, 2, 6, 6-tetrakis (hydroxymethyl) cyclohexanol, and an HDI polymer; and the resin component is hydroxyl resin. The coating disclosed by the invention is applied to the cement-based floor cover surface, has the characteristics of yellowing resistance, excellent mechanical property, quick construction and quick use, and solves the problems of poor adhesive force, easiness in falling and no yellowing resistance of the existing cement-based floor cover surface.

Description

Technical Field

[0001] The present invention relates to the technical field of polyurethane floorings, and particularly to a yellowing-resistant coating for cement-based floor surfacing and its application method. Background Art

[0002] Cement-based wear-resistant floor materials are dry-mixed materials composed of portland cement, wear-resistant aggregates, and appropriate additives. Compared with ordinary cement floors, cement-based wear-resistant floors have the characteristics of high strength and good wear resistance; due to the addition of cement curing agents and wear-resistant aggregates, the wear resistance is several times that of cement floors. Due to its excellent performance, it is increasingly used in places such as highways, airport runways, warehouses, docks, supermarkets, etc. However, cement-based wear-resistant materials also have disadvantages such as poor cleanliness, easy intrusion of stains into the interior, poor decoration, and dust generation, which hinder their popularization in scenarios such as food workshops and electronic clean workshops.

[0003] The traditional method is to use materials such as epoxy floor materials, but due to the very dense surface of cement-based wear-resistant floors, it will cause the floor to peel off and have a short lifespan. Moreover, under light, the color of the floor coating will turn yellow, resulting in a decrease in aesthetics. In addition, the wear resistance of epoxy resin materials is relatively poor, making them unable to be used in clean workshops. Patent CN107892870A synthesizes a polyurethane mask layer using a mixture of HDI biuret and HDI monomers. The product is a two-component product, with complicated construction steps and unable to meet the requirements for hardness in cement-based wear-resistant floors, average wear resistance, and relatively low product safety.

[0004] In order to solve the defects of current cement-based wear-resistant floor materials in terms of surface adhesion, decoration, durability, etc., it is necessary to develop a coating for cement-based wear-resistant floor surfacing with high decoration, high strength, and long lifespan. Summary of the Invention

[0005] The purpose of the present invention is to provide a yellowing-resistant coating for cement-based floor surfacing, which is used in the field of floor materials. The cement-based wear-resistant floor surfacing is different from the traditional aliphatic isocyanate and polyol systems. This surfacing has the characteristics of yellowing resistance, high hardness, and high adhesion, and solves the disadvantages of traditional materials such as easy peeling, short lifespan, and poor decoration.

[0006] Another purpose of the present invention is to provide an application method for this yellowing-resistant coating for cement-based floor surfacing.

[0007] To solve the above technical problems, the present invention provides the following technical solutions:

[0008] (1) An isocyanate curing agent component, including

[0009] a) An IPDI adduct, an IPDI adduct prepared by reacting isophorone diisocyanate (IPDI) with 2,2,6,6 - tetrakis(hydroxymethyl)cyclohexanol;

[0010] b) Optional HDI polymer;

[0011] (2) The resin component is a hydroxyl resin.

[0012] In some specific embodiments, the method for preparing the IPDI adduct includes the following steps:

[0013] Under nitrogen protection, at a temperature of 70 - 120 °C, such as temperature conditions of 70 °C, 80 °C, 90 °C, 100 °C, 110 °C, 120 °C, etc., slowly drop 2,2,6,6 - tetrakis(hydroxymethyl)cyclohexanol into IPDI, and then monitor the content of NCO. After the mass fraction of NCO reaches the theoretical value, the IPDI adduct is obtained. Among them, the dropping rate has no special limitation. For example, 10 g of 2,2,6,6 - tetrakis(hydroxymethyl)cyclohexanol is slowly added to 120 g of IPDI and added within 3 minutes. The mass fraction of NCO reaching 28% is the theoretical end point.

[0014] In some specific embodiments, the molar ratio of IPDI to 2,2,6,6 - tetrakis(hydroxymethyl)cyclohexanol is 5:1 - 25:1; such as 5:1, 6:1, 7:1, 8:1, 9:1, 10:1, 11:1, 12:1, 13:1, 14:1, 15:1, 16:1, 17:1, 18:1, 19:1, 20:1, 21:1, 22:1, 23:1, 24:1, 25:1, etc., and preferably 8:1 - 15:1.

[0015] In some specific embodiments, the HDI polymer includes at least any one of HDI dimer, HDI trimer, HDI pentamer, HDI heptamer, HDI nonamer, HDI polymer; for example, it contains HDI trimer and other polymers. Preferably, the mass content of the trimer in the HDI polymer is 10 - 80%, such as 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, etc., and preferably 10 - 50%; more preferably, the viscosity of the HDI polymer at 25 °C is 300 - 1200 mPa·s, such as 300 mPa·s, 400 mPa·s, 500 mPa·s, 600 mPa·s, 700 mPa·s, 800 mPa·s, 900 mPa·s, 1000 mPa·s, 1100 mPa·s, 1200 mPa·s, etc.

[0016] In some specific embodiments, the HDI polymer accounts for 0 to 50 wt% of the total mass of the isocyanate curing agent component, such as 0, 10 wt%, 15 wt%, 20 wt%, 25 wt%, 30 wt%, 35 wt%, 40 wt%, 45 wt%, 50 wt%, etc.; preferably 30 to 50 wt%.

[0017] In some specific embodiments, the resin component is selected from modified castor oil resins; preferably, it is selected from modified castor oil resins with a hydroxyl value of 200 to 400 mgKOH, such as 250 mgKOH, 300 mgKOH, 350 mgKOH, etc., and a viscosity at 25°C of 750 to 1500 mPa·s, such as 800 mPa·s, 850 mPa·s, 900 mPa·s, 950 mPa·s, 1000 mPa·s, 1100 mPa·s, 1200 mPa·s, 1300 mPa·s, 1400 mPa·s, 1500 mPa·s, etc., and a functionality of 2.5 to 4.0, such as modified castor oil resins with functionality 2.5, 3, 3.5, 4. The modified castor oil resins of the present invention are, for example, BASF 750 resin, 4105 resin of Shanghai Jingri New Materials Co., Ltd., etc., but are not limited thereto.

[0018] In some specific embodiments, a solvent is further included, and the addition amount of the solvent accounts for 0 to 40% of the total mass of the coating system, such as 1%, 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, etc., and is preferably 5 to 15%.

[0019] In some specific embodiments, the solvent is selected from at least any one of dimethyl mixed dibasic acid esters, propylene glycol methyl ether propionate, ethylene glycol diacetate, propylene glycol diacetate, butyl acetate, xylene, and ethyl acetate.

[0020] In some specific embodiments, the molar ratio of NCO in the isocyanate curing agent component to OH in the resin component is 1 to 2, such as 1, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2, etc., and preferably, the molar ratio of NCO to OH is 1.2 to 1.5.

[0021] In some specific embodiments, a wetting agent and a catalyst are further included; preferably, the catalyst is selected from at least any one of bismuth-based and tin-based catalysts. Among them, both bismuth-based and tin-based catalysts are common catalysts in the polyurethane field, such as dibutyltin dilaurate, etc. The addition amount of the catalyst accounts for 0 to 0.5% of the total mass of the coating system, such as 0, 0.01%, 0.02%, 0.05%, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, etc., and is preferably 0.02% to 0.1%.

[0022] The wetting agent is selected from one or more of wetting agents such as BYK333, BYK310, ZY-2702, etc. Preferably, the addition amount of the wetting agent is 0 to 0.5% of the total mass of the coating system, such as 0, 0.01%, 0.02%, 0.05%, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, etc., and preferably 0.2% to 0.5%.

[0023] In the present invention, the total mass of the coating system refers to the total mass of all components such as the aforementioned isocyanate curing agent component, resin component, and optionally solvent, optionally catalyst, optionally wetting agent, etc., which is well known to those skilled in the art.

[0024] On the other hand, the using method of the yellowing-resistant cement-based floor finish coating includes the steps of mixing the isocyanate curing agent component and the resin component evenly and performing brushing construction; preferably any one of scraping, roller coating, and spraying is used, and preferably roller coating and spraying.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] In the present invention, an adduct of 2,2,6,6-tetrakis(hydroxymethyl)cyclohexanol and IPDI is introduced into the system. The strong cyclic structure of IPDI itself reacts with the cyclic compound with 5 hydroxyl groups, and the prepared IPDI adduct has a high functionality. It reacts with a hydroxyl resin with the same high functionality (such as modified castor oil resin), and has short branches, significantly improving the film hardness, enhancing the wear resistance and service life of the film. At the same time, the high functionality brings more urethane groups reacting with the resin, greatly improving the adhesion between the film and the cement substrate. At the same time, it is unexpectedly found that the introduction of 2,2,6,6-tetrakis(hydroxymethyl)cyclohexanol compound greatly enhances the weather resistance, yellowing resistance, and organic acid resistance of the film.

[0027] The yellowing-resistant cement-based wear-resistant floor finish coating of the present invention overcomes the disadvantages of traditional floors such as easy peeling off, poor adhesion, and easy yellowing, improves the mechanical properties and weather resistance of the film, and makes it very suitable for use as a finish on cement-based wear-resistant floors. Detailed Embodiments

[0028] In order to more clearly describe the technical solutions and beneficial effects of the present invention, the following further explains the specific embodiments of the present invention, but the present invention is not limited to the embodiments described below.

[0029] The main raw materials used in the embodiments of the present invention are as follows

[0030] IPDI, Wanhua Chemical;

[0031] HDI polymer, grade HT-600, Wanhua Chemical;

[0032] IPDI trimer, grade IP-170B, Wanhua Chemical;

[0033] 2,2,6,6-Tetrakis(hydroxymethyl)cyclohexanol, Aladdin Reagent;

[0034] Catalyst, dibutyltin dilaurate, Aladdin Reagent;

[0035] Resin, 750, BASF;

[0036] Resin, 4105, Shanghai Jingri New Materials Co., Ltd.;

[0037] Mixed dibasic acid dimethyl ester, Aladdin Reagent.

[0038] Example 1

[0039] Isocyanate curing agent component, the molar ratio of isophorone diisocyanate (IPDI) to 2,2,6,6-tetrakis(hydroxymethyl)cyclohexanol is 10:1, the mass fraction of IPDI is 54.5 parts, 2,2,6,6-tetrakis(hydroxymethyl)cyclohexanol is 5.5 parts. After the reaction at 90 °C is completed, 40 parts of HT-600 are added.

[0040] A total of 20 parts of BASF 750 resin as the resin component, 25.3 parts of the isocyanate component, 7.4 parts of the mixed dibasic acid dimethyl ester, and 500 ppm of dibutyltin dilaurate as the catalyst are sprayed on the cement-based wear-resistant floor. Designated as A.

[0041] Example 2

[0042] Isocyanate curing agent component, the molar ratio of isophorone diisocyanate (IPDI) to 2,2,6,6-tetrakis(hydroxymethyl)cyclohexanol is 16:1, the mass fraction of IPDI is 47.1 parts, 2,2,6,6-tetrakis(hydroxymethyl)cyclohexanol is 2.9 parts. After the reaction at 80 °C is completed, 50 parts of HT-600 are added.

[0043] A total of 20 parts of BASF 750 resin as the resin component, 23.6 parts of the isocyanate component, 1.3 parts of the mixed dibasic acid dimethyl ester, and 500 ppm of dibutyltin dilaurate as the catalyst are sprayed on the cement-based wear-resistant floor. Designated as B.

[0044] Example 3

[0045] Isocyanate curing agent component, the molar ratio of isophorone diisocyanate (IPDI) to 2,2,6,6-tetrakis(hydroxymethyl)cyclohexanol is 8:1, the mass fraction of IPDI is 61.3 parts, 2,2,6,6-tetrakis(hydroxymethyl)cyclohexanol is 7.7 parts. After the reaction at 120 °C is completed, 31 parts of HT-600 are added.

[0046] Add 20 parts of the resin component BASF 750 resin, 27 parts of the isocyanate component, 7.7 parts of mixed dimethyl adipate, and add 500 ppm of dibutyltin dilaurate as the catalyst, then spray it on the cement-based wear-resistant floor. The number is C.

[0047] Example 4

[0048] For the isocyanate curing agent component, the molar ratio of isophorone diisocyanate (IPDI) to 2,2,6,6-tetrakis(hydroxymethyl)cyclohexanol is 23:1, the mass of IPDI is 80.5 parts, and the mass of 2,2,6,6-tetrakis(hydroxymethyl)cyclohexanol is 3.5 parts. After the reaction ends at 72 °C, add 16 parts of HT-600.

[0049] Add 20 parts of the resin component Shanghai Jingri 4105 resin, 20 parts of the isocyanate component, 17.1 parts of mixed dimethyl adipate, and add 500 ppm of dibutyltin dilaurate as the catalyst, then spray it on the cement-based wear-resistant floor. The number is D.

[0050] Example 5

[0051] For the isocyanate curing agent component, the molar ratio of isophorone diisocyanate (IPDI) to 2,2,6,6-tetrakis(hydroxymethyl)cyclohexanol is 7:1, the mass of IPDI is 87.5 parts, and the mass of 2,2,6,6-tetrakis(hydroxymethyl)cyclohexanol is 12.5 parts. After the reaction ends at 71 °C.

[0052] Add 20 parts of the resin component Shanghai Jingri 4105 resin, 29 parts of the isocyanate component, 18.1 parts of mixed dimethyl adipate, and add 500 ppm of dibutyltin dilaurate as the catalyst, then spray it on the cement-based wear-resistant floor. The number is D.

[0053] Comparative Example 1

[0054] Add 20 parts of the resin component BASF 750 resin, 27.9 parts of the HT-600 component, 7.8 parts of mixed dimethyl adipate, and add 500 ppm of dibutyltin dilaurate as the catalyst, then spray it on the cement-based wear-resistant floor.

[0055] Comparative Example 2

[0056] For the isocyanate curing agent component, use a blend of 60 parts of IT-170B and 40 parts of HT-600.

[0057] Add 20 parts of the resin component Shanghai Jingri 4105 resin, 38.3 parts of the isocyanate component, 9.5 parts of mixed dimethyl adipate, and add 500 ppm of dibutyltin dilaurate as the catalyst, then spray it on the cement-based wear-resistant floor.

[0058] Testing methods and results

[0059] Test the conventional and yellowing resistance indicators: According to the national standard "GB / T 22374-2018 Floor Coating Materials", test the pencil hardness, pot life, adhesion, abrasion resistance, water resistance (168 hours), alkali resistance (20% NaOH, 72h), acid resistance (10% sulfuric acid, 48h), oil resistance (120# solvent oil, 72h), color difference after QUV (600h) of artificial aging resistance, etc. of the key indicators before testing, and test the Shore D hardness through the samples without solvents in the above examples and comparative examples.

[0060] Table 1 Conventional Test Results of Floor

[0061]

[0062] It can be seen from Table 1 that the performances of Examples A to E are all good, especially excellent in terms of hardness and yellowing resistance. The solution of the present invention is very suitable for the surface coating material of cement-based floors, and can effectively ensure the durability and beauty of the material.

[0063] The above-mentioned embodiments are the preferred specific embodiments of the present invention, and the present invention includes but is not limited to the limitations of the above embodiments. Those of ordinary skill in the relevant art should understand that after reading the specification of this application, any changes, modifications, substitutions, combinations, and simplifications made without departing from the spirit and principle of the present invention should be equivalent replacement methods and are all included in the protection scope of the present invention.

Claims

1. A yellowing-resistant coating for cement-based floor surface, characterized in that, it comprises the following components: (1) Isocyanate curing agent component, including a) IPDI adduct, an IPDI adduct prepared by reacting isophorone diisocyanate (IPDI) with 2,2,6,6-tetrakis(hydroxymethyl)cyclohexanol; b) Optional HDI polymer; (2) Resin component, which is a hydroxyl resin type.

2. The yellowing-resistant coating for cement-based floor surface according to claim 1, characterized in that, the preparation method of the IPDI adduct comprises the following steps: Under the protection of nitrogen, at a temperature of 70 - 120°C, slowly drop 2,2,6,6-tetrakis(hydroxymethyl)cyclohexanol into IPDI, and then monitor the content of NCO. After the mass fraction of NCO reaches the theoretical value, the IPDI adduct is obtained.

3. The yellowing-resistant coating for cement-based floor surface according to claim 1 or 2, characterized in that, the molar ratio of IPDI to 2,2,6,6-tetrakis(hydroxymethyl)cyclohexanol is 5:1 - 25:1; preferably 8:1 - 15:

1.

4. The yellowing-resistant coating for cement-based floor surface according to claim 1, characterized in that, the HDI polymer includes at least any one of HDI dimer, HDI trimer, HDI pentamer, HDI heptamer, HDI nonamer, HDI polymer; preferably, the mass content of the trimer in the HDI polymer is 10 - 80%, preferably 10 - 50%; more preferably, the viscosity of the HDI polymer at 25°C is 300 - 1200 mPa·s; and / or the HDI polymer accounts for 0 - 50 wt% of the total mass of the isocyanate curing agent component; preferably 30 - 50 wt%.

5. The yellowing-resistant coating for cement-based floor surface according to claim 1, characterized in that, the resin component is selected from modified castor oil resin; preferably, it is selected from modified castor oil resin with a hydroxyl value of 200 - 400 mgKOH, a viscosity at 25°C of 750 - 1500 mPa·s, and a functionality of 2.5 - 4.

0.

6. The yellowing-resistant coating for cement-based floor surface according to claim 1, characterized in that, it further includes a solvent, and the addition amount of the solvent accounts for 0 - 40% of the total mass of the coating system, preferably 5 - 15%.

7. The yellowing-resistant coating for cement-based floor surface according to claim 6, characterized in that, the solvent is selected from at least any one of dimethyl mixed dibasic acid ester, propylene glycol methyl ether propionate, ethylene glycol diacetate, propylene glycol diacetate, butyl acetate, xylene, ethyl acetate.

8. The yellowing-resistant coating for cement-based floor surface according to claim 1, characterized in that, the molar ratio of NCO in the isocyanate curing agent component to OH in the resin component is 1 - 2, preferably, the molar ratio of NCO to OH is 1.2 - 1.

5.

9. The yellowing-resistant coating for cement-based floor surface according to claim 1 or 6, characterized in that, It also includes a wetting agent and a catalyst; preferably, the catalyst is selected from at least one of bismuth-based and tin-based, and the addition amount of the catalyst is 0 to 0.5% of the total mass of the coating system, preferably 0.02% to 0.1%; and / or The wetting agent is selected from one or more of BYK333, BYK310, and ZY-2702. Preferably, the addition amount of the wetting agent is 0 to 0.5% of the total mass of the coating system, preferably 0.2% to 0.5%.

10. The method of using the yellowing-resistant cement-based floor finish coating according to any one of claims 1 to 9, characterized in that it includes the steps of mixing the isocyanate curing agent component and the resin component evenly and performing brushing construction; preferably, any one of scraping, roller coating, and spraying is used.

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