Strongly adherent and highly weather-resistant water-based fluorocarbon paint for GRPU substrate and preparation method thereof

Abstract

The present application relates to the technical field of water-based coatings, and specifically discloses a water-based fluorocarbon paint with strong adhesion and high weather resistance for GRPU substrates and a preparation method thereof. A water-based fluorocarbon paint with strong adhesion and high weather resistance for GRPU substrates, comprising component A and component B; the component A comprises the following components in parts by weight: 55-60 parts of trifluoroether water-based fluorocarbon resin with a hydroxyl value of 60-70 mgK0H / g; 4-6 parts of solvent; 7.3 parts of water; 1.5-2 parts of dispersant; 22-27 parts of filler; the component B comprises the following components in parts by weight: 40-60 parts of organosilicon-modified isocyanate trimer curing agent; 6-9 parts of silane coupling agent; 31-54 parts of diluent. The water-based fluorocarbon paint of the present application can be used on the surface of GRPU substrates in a long-term water-immersion environment, and has the advantages of high adhesion and strong water resistance.

Description

Technical Field

[0001] The present application relates to the technical field of water-based coatings, and more specifically, to a water-based fluorocarbon paint with strong adhesion and high weather resistance for GRPU substrates and a preparation method thereof. Background Art

[0002] GRPU, glass fiber reinforced polyurethane, is a low-energy, environmentally friendly composite material, mainly used in building materials industries such as doors and windows. The paint used on the surface of GRPU substrates is divided into oil-based paint and water-based paint. Oil-based paint contains harmful substances such as benzene and formaldehyde, and has high VOC emissions, which poses environmental pollution problems. Therefore, the use of water-based paint is becoming more and more widespread.

[0003] The preparation of GRPU substrate is mainly based on pultrusion process. In order to maintain continuous pultrusion out of the mold after in-mold molding, a release agent will be added to it. Most of these release agents will adhere to the surface of the GRPU substrate, and the silicon component contained in the release agent makes the profile surface partially non-polar. At this time, the various interaction forces between the profile and the water-based paint film containing a large number of polar groups will decrease, making it difficult for the water-based paint to adhere to the GRPU substrate.

[0004] At present, there is a two-component polyurethane coating for glass fiber reinforced polyurethane substrate, which has low adhesion. At the same time, due to the use of sulfonate hydrophilic modified hexamethylene diisocyanate containing hydrophilic groups as a curing agent, the water resistance of the coating is poor. Once the substrate is immersed in water for a long time, the coating will often have problems such as bubbles and shedding, which makes it difficult to use GRPU substrates in outdoor and indoor bathroom environments where they are exposed to water for a long time. Summary of the invention

[0005] In order to improve the adhesion of water-based paint on the surface of GRPU substrate after long-term immersion in water, the present application provides a water-based fluorocarbon paint with strong adhesion and high weather resistance for GRPU substrate and a preparation method thereof.

[0006] In the first aspect, the present application provides a water-based fluorocarbon paint with strong adhesion and high weather resistance for GRPU substrate, which adopts the following technical solution:

[0007] A water-based fluorocarbon paint with strong adhesion and high weather resistance for GRPU substrate, comprising component A and component B;

[0008] The A component includes the following components in parts by weight:

[0009] 55-60 parts of trifluoroether water-based fluorocarbon resin having a hydroxyl value of 60-70 mgKOH / g;

[0010] 4-6 parts of solvent;

[0011] 7.3 parts of water;

[0012] Dispersant 1.5-2 parts;

[0013] 22-27 parts of filler;

[0014] The B component includes the following components in parts by weight:

[0015] 40-60 parts of silicone modified isocyanate trimer curing agent;

[0016] Silane coupling agent 6-9 parts;

[0017] Diluent 31-54 parts.

[0018] By adopting the above technical scheme: using trifluorochloroethylene and vinyl ether alternating copolymer as the main film-forming material, and the two-component room temperature curing coating composed of isocyanate. Wherein fluorocarbon resin is based on CC bond as the main chain, the electronegativity of the fluorine atom contained is extremely large, and the atomic radius is large, resulting in a large force between the unbonded atoms, so that the fluorine atom is in close contact and covers the CC bond into a complete cylinder, which plays a shielding type of protection for the CC bond. In addition, the FC bond energy (486KJ / mol) formed between the fluorine atom and the carbon atom is extremely large, which is much higher than the bond energy of CH bond (410KJ / mol), CO bond (360KJ / mol), CC bond (356KJ / mol and C-CI bond (326KJ / mol), etc., in summary, the fluorocarbon paint of the present application has excellent weather resistance.

[0019] At the same time, low-hydroxyl water-based fluorocarbon resin is selected, which has a low cross-linking density with the curing agent. The rigidity of the cured paint film decreases and it is easy to penetrate into the gaps on the surface of the substrate, thereby increasing the area of ​​the paint film anchoring the substrate, that is, the mechanical bonding adhesion of the paint film is enhanced; the inorganic end in the silane coupling agent is hydrolyzed into silicon hydroxyl groups, and the silicon hydroxyl groups condense with the hydroxyl groups on the surface of the inorganic matrix to form covalent bonds, while the organic end forms a coupling with the organic matrix, that is, a bond of organic film-forming resin-coupling agent-inorganic glass fiber is formed. In summary, the adhesion of the paint film to the GRPU substrate is improved.

[0020] The silicone modified isocyanate trimer curing agent contains a polysiloxane silicone segment on one of the main chains of the trimer, which has excellent hydrophobic properties and can reduce the hydrophilic properties of sulfonates. Therefore, the paint film cross-linked and cured with the water-based fluorocarbon FEVE secondary dispersion has excellent water resistance. It can solve the problem of poor long-term water resistance of water-based paint films used with GRPU in bathroom doors and windows.

[0021] Optionally, the trifluoroether water-based fluorocarbon resin has a fluorine content of ≥13%.

[0022] By adopting the above technical solution: controlling the fluorine content to ≥13%, the coating has a lower friction coefficient after film formation and improves wear resistance.

[0023] Optionally, the organosilicon-modified isocyanate trimer curing agent is Wanhua Aquolin 280 curing agent.

[0024] Optionally, the silane coupling agent is y-glycidyloxypropyltrimethoxysilane.

[0025] By adopting the above technical scheme: the inorganic end (-Si-OR3) in y-glycidyloxypropyltrimethoxysilane (YR-Si-OR3) is hydrolyzed into silanol (-Si-OH3), and the silanol and the hydroxyl groups on the surface of the inorganic matrix are condensed to form a covalent bond, while the organic end (-Y) forms a coupling with the organic matrix, that is, a bond of organic film-forming resin-YR-Si-O-inorganic glass fiber is formed, thereby improving the chemical bond adhesion between the paint film and the GRPU substrate.

[0026] Optionally, the dispersant is a mixture of a nonionic polymeric dispersant and 2-hydroxy-4-methoxyacetophenone.

[0027] By adopting the above technical solution: the non-ionic polymeric dispersant disperses the filler by anchoring steric hindrance, and no charge repulsion ionization occurs. During the drying process of the paint film, the hydrophilic chain segment of the non-ionic polymeric dispersant does not stretch, and has little effect on water resistance. The compounding of 2-hydroxy-4-methoxyacetophenone may increase the steric hindrance of the dispersant or improve the adsorption effect on the filler surface, thereby improving the dispersibility of the dispersant on the filler and making the coating more water resistant.

[0028] Optionally, the weight ratio of the nonionic polymeric dispersant to 2-hydroxy-4-methoxyacetophenone is 1:(0.3-0.5).

[0029] Optionally, the weight ratio of component A to component B is (5.8-6.2):1.

[0030] In the second aspect, the present application provides a method for preparing a water-based fluorocarbon paint with strong adhesion and high weather resistance for a GRPU substrate, using the following technical solution:

[0031] A method for preparing a water-based fluorocarbon paint with strong adhesion and high weather resistance for a GRPU substrate comprises the following steps:

[0032] S1. Mix a dispersant and water, add a filler and stir to obtain a dispersion slurry; mix a trifluoroether water-based fluorocarbon resin, a solvent and a dispersion slurry, stir to mix, and adjust the pH to 7.5-8.5 to obtain component A;

[0033] S2, blending the diluent and the silane coupling agent, adding the isocyanate curing agent and stirring and mixing to obtain component B;

[0034] S3, mix component A and component B to obtain.

[0035] By adopting the above technical solution: fewer process steps, a simple and efficient process, which is conducive to the large-scale preparation of fluorocarbon paint. The prepared fluorocarbon paint has an adhesion of up to level one on the surface of the GRPU substrate, a water resistance time of up to 380 hours, and excellent performance, and can be applied to the surface of the GRPU substrate in a long-term water immersion environment.

[0036] In summary, this application has the following beneficial effects:

[0037] 1. This application adopts trifluoroether water-based fluorocarbon resin with a specific hydroxyl value, compounded with silane coupling agent and organosilicon modified curing agent, so that the adhesion of the prepared paint film on the surface of the GRPU substrate reaches level one, and the water resistance reaches 320h, which can be applied to the surface of the GRPU substrate in a long-term water immersion environment;

[0038] 2. Specific silane coupling agents and dispersants are used in this application to ensure that the paint film has better adhesion and water resistance;

[0039] 3. The dispersant of the present application adopts a mixture of a nonionic polymeric dispersant and 2-hydroxy-4-methoxyacetophenone. 2-hydroxy-4-methoxyacetophenone enhances the dispersing effect of the nonionic dispersant on the filler, making the water resistance of the paint film better. DETAILED DESCRIPTION

[0040] The present application is further described in detail below in conjunction with the embodiments. The water-based fluorocarbon paint of the present application is a two-component paint. When stored, components A and B are stored separately, and when used, components A and B are blended and used.

[0041] The sources of the components are as follows. Except for the following special instructions, the components are commercially available:

[0042] Trifluoroether water-based fluorocarbon resin, sourced from Shandong Jiaying Chemical Technology Co., Ltd., model DF-03B, hydroxyl value 60-70 mgK0H / g, fluorine content 13%;

[0043] Titanium dioxide, sourced from Longbai Group Co., Ltd., model R-996;

[0044] Silicone-modified isocyanate trimer curing agent, purchased from Wanhua Chemical Group Co., Ltd., model Aquolin 280.

[0045] Example 1

[0046] A water-based fluorocarbon paint with strong adhesion and high weather resistance for GRPU substrate is prepared by the following steps:

[0047] S1. Add 1.6 kg of nonionic polymer dispersant (manufacturer: Allnex Resin, ADDITOL VXW6208 / 60), 0.2 kg of defoamer (BYK-024), and 0.6 kg of rheological agent (Guangdong Qirun New Materials Co., Ltd., QD06) to 7.3 kg of water, stir and mix, add 25 kg of filler (titanium dioxide) while stirring at a speed of 600 rpm, and stir at a speed of 1500 rpm until the fineness is 15 μm to obtain a dispersed slurry;

[0048] 58 kg of trifluoroether water-based fluorocarbon resin was put into a reactor, stirring was started, and 0.3 kg of wetting agent (Twin 4100 from Germany) , defoaming agent (0.5 kg of SURFYNOL 104E from Germany, 0.2 kg of AGITAN 158 from Germany), 0.5 kg of BYK-3720, solvent (2 kg of ethylene glycol monobutyl ether, 3 kg of dipropylene glycol butyl ether) and the above dispersion slurry were added in sequence at a speed of 500 rpm while stirring, and stirring was continued for 30 min, and then a pH adjuster (N, N-dimethylethanolamine) and 0.6 kg of rheological agent (Qirun New Materials Co., Ltd., Guangdong, QD06) were added, and the pH was adjusted to 8 to obtain component A;

[0049] S3, add 8kg of silane coupling agent (y-glycidyloxypropyltrimethoxysilane) to 42kg of diluent (dibasic acid ester), stir and mix, add 50kg of organosilicon-modified isocyanate trimer curing agent while stirring, stir and mix, and obtain component B;

[0050] S3. Mix component A and component B in a weight ratio of 6:1 to obtain.

[0051] Example 2

[0052] A water-based fluorocarbon paint with strong adhesion and high weather resistance for GRPU substrate, the components and their corresponding weights are shown in Table 1, and is prepared by the following steps:

[0053] S1. Add 1.5 kg of nonionic polymer dispersant (Zhanxin resin, ADDITOL VXW 6208 / 60), 0.2 kg of defoamer (BYK-024), and 0.4 kg of rheological agent (Guangdong Qirun New Materials Co., Ltd., QD06) to 7.3 kg of water, stir and mix, add 22 kg of filler (titanium dioxide) while stirring at a speed of 600 rpm, and stir at a speed of 1500 rpm until the fineness is 15 μm to obtain a dispersion slurry;

[0054] 55 kg of trifluoroether water-based fluorocarbon resin was put into a reaction kettle, stirring was started, and 0.2 kg of wetting agent (Twin 4100 from Germany) , defoaming agent (0.3 kg SURFYNOL 104E from Germany, 0.2 kg AGITAN 158 from Germany), 0.3 kg BYK-3720, solvent (2 kg ethylene glycol monobutyl ether, 2 kg dipropylene glycol butyl ether) and the above dispersion slurry were added in sequence at a speed of 500 rpm while stirring, and stirring was continued for 30 min, and then a pH adjuster (N, N-dimethylethanolamine) and 0.4 kg rheological agent (Qirun New Materials Co., Ltd., Guangdong, QD06) were added, and the pH was adjusted to 7.5 to obtain component A;

[0055] S3, add 6 kg of silane coupling agent (y-glycidyloxypropyltrimethoxysilane) to 54 kg of diluent (divalent acid ester), stir and mix, add 40 kg of organosilicon-modified isocyanate trimer curing agent while stirring, stir and mix, and obtain component B;

[0056] S3. Mix component A and component B in a weight ratio of 5.8:1 to obtain.

[0057] Example 3

[0058] A water-based fluorocarbon paint with strong adhesion and high weather resistance for GRPU substrate, the components and their corresponding weights are shown in Table 1, and is prepared by the following steps:

[0059] S1. Add 2 kg of nonionic polymer dispersant (Zhanxin resin, ADDITOL VXW 6208 / 60), 0.4 kg of defoamer (BYK-024), and 0.8 kg of rheological agent (Guangdong Qirun New Materials Co., Ltd., QD06) to 7.3 kg of water, stir and mix, add 27 kg of filler (titanium dioxide) while stirring at a speed of 600 rpm, and stir at a speed of 1500 rpm until the fineness is 15 μm to obtain a dispersion slurry;

[0060] 60 kg of trifluoroether water-based fluorocarbon resin was put into a reactor, stirring was started, and 0.4 kg of wetting agent (Twin 4100 from Germany) , defoaming agent (0.8 kg SURFYNOL 104E from Germany, 0.4 kg AGITAN 158 from Germany), 0.8 kg BYK-3720, solvent (3 kg ethylene glycol monobutyl ether, 3 kg dipropylene glycol butyl ether) and the above dispersion slurry were added in sequence at a speed of 500 rpm while stirring, and stirring was continued for 30 min, and then a pH adjuster (N, N-dimethylethanolamine) and 0.8 kg rheological agent (Qirun New Materials Co., Ltd., Guangdong, QD06) were added, and the pH was adjusted to 8.5 to obtain component A;

[0061] S3, add 9 kg of silane coupling agent (γ-glycidyloxypropyltrimethoxysilane) to 31 kg of diluent (divalent acid ester), stir and mix, add 60 kg of organosilicon-modified isocyanate trimer curing agent while stirring, stir and mix, and obtain component B;

[0062] S3, mix component A and component B in a weight ratio of 6.2:1 to obtain.

[0063] Embodiment 4-6

[0064] A water-based fluorocarbon paint with strong adhesion and high weather resistance for GRPU substrate, in which the use of dispersants is different, a mixture of a non-ionic polymeric dispersant (allnex resin, ADDITOL VXW 6208 / 60) and 2-hydroxy-4-methoxyacetophenone in the following weight ratio is used instead of ADDITOL VXW 6208 / 60, as follows:

[0065] Example 4: A mixture of ADDITOL VXW 6208 / 60 and 2-hydroxy-4-methoxyacetophenone in a weight ratio of 1:0.3.

[0066] Example 5: A mixture of ADDITOL VXW 6208 / 60 and 2-hydroxy-4-methoxyacetophenone in a weight ratio of 1:0.4.

[0067] Example 6: A mixture of ADDITOL VXW 6208 / 60 and 2-hydroxy-4-methoxyacetophenone in a weight ratio of 1:0.6.

[0068] Comparative Example 1

[0069] A water-based paint, which is different from Example 1 in that an equal amount of water-based acrylate dispersion resin is used instead of a trifluoroether water-based fluorocarbon resin, and an equal amount of Covestro Bayhydur 2655 curing agent is used instead of a silicone-modified isocyanate trimer curing agent.

[0070] Comparative Example 2

[0071] A water-based fluorocarbon paint, which is different from Example 1 in that the amount of water-based fluorocarbon resin used is different, and the amount used is 50 kg.

[0072] Comparative Example 3

[0073] A water-based fluorocarbon paint, which is different from Example 1 in that the amount of water-based fluorocarbon resin used is different, and the amount used is 50 kg.

[0074] Comparative Example 4

[0075] A water-based fluorocarbon paint, which is different from Example 1 in that the hydroxyl value of the water-based fluorocarbon resin is different. The water-based fluorocarbon resin of this comparative example is obtained from Shanghai Deyude Trading Co., Ltd., with a brand name of CX-802, a hydroxyl value of 20-30 mgK0H / g, and a fluorine content of 10%.

[0076] Comparative Example 5

[0077] A water-based fluorocarbon paint, which is different from Example 1 in that the hydroxyl value of the water-based fluorocarbon resin is different. The water-based fluorocarbon resin of this comparative example is obtained from Shandong Jiaying Chemical Technology Co., Ltd., model DF-M05, hydroxyl value 70-90 mgK0H / g, fluorine content> 18%.

[0078] Comparative Example 6

[0079] A water-based fluorocarbon paint is different from Example 1 in that the use of the isocyanate curing agent is different, and an equal amount of isophorone diisocyanate is used instead of the silicone-modified isocyanate trimer curing agent.

[0080] Performance Testing

[0081] The coatings prepared in the examples and comparative examples were subjected to the following performance tests, and the test results are recorded in Table 1.

[0082] Detection Methods

[0083] 1. Adhesion: The test was conducted according to GB / T 9286-1998 “Scratching test for paint and varnish films”. The test panel was made of glass fiber reinforced polyurethane substrate (GRPU substrate) with a thickness of 0.3 mm. The surface oil was not cleaned before use.

[0084] 2. Water resistance: Test according to GB / T 1733-1993 "Determination of water resistance of paint film" and record the time when the coating on the test plate begins to wrinkle. The longer the time, the better the water resistance.

[0085] Table 1 Performance test results

[0086]

[0087]

[0088] Referring to the data in Table 1, in Examples 1-3, due to the use of trifluoroether water-based fluorocarbon resins with specific hydroxyl values, compounded with silane coupling agents and organosilicon-modified curing agents, the prepared paint films have a first-level adhesion on the surface of the GRPU substrate and a water resistance of 320 hours; while the paint film of Comparative Example 1 has a lower adhesion on the surface of the GRPU substrate than the second level, and a water resistance of 240 hours. This shows that the adhesion and water resistance of the paint film of the present application are better than those of commercially available products.

[0089] The difference between Comparative Examples 2-6 and Example 1 is that the amount of resin or the hydroxyl value of the resin or the curing agent used is different, and the performance of the prepared paint film is reduced.

[0090] The difference between Example 4-6 and Example 1 is that the dispersant used is a mixture of a non-ionic polymeric dispersant and 2-hydroxy-4-methoxyacetophenone. Compared with a single dispersant, the water resistance of the paint film is significantly improved.

[0091] This specific embodiment is merely an explanation of the present application and is not a limitation of the present application. After reading this specification, those skilled in the art may make modifications to the present embodiment without any creative contribution as needed, but such modifications are protected by the patent law as long as they are within the scope of the claims of the present application.

Claims

1. A water-based fluorocarbon paint with strong adhesion and high weather resistance for GRPU substrate, characterized in that: It includes component A and component B; The A component includes the following components in parts by weight: 55-60 parts of trifluoroether water-based fluorocarbon resin having a hydroxyl value of 60-70 mgKOH / g; 4-6 parts of solvent; Water 7.3 parts; Dispersant 1.5-2 parts; 22-27 parts of filler; The B component includes the following components in parts by weight: 40-60 parts of silicone modified isocyanate trimer curing agent; Silane coupling agent 6-9 parts; 31-54 parts of diluent; The dispersant is a mixture of a nonionic polymeric dispersant and 2-hydroxy-4-methoxyacetophenone; The weight ratio of the nonionic polymer dispersant to 2-hydroxy-4-methoxyacetophenone is 1:(0.3-0.5).

2. The water-based fluorocarbon paint with strong adhesion and high weather resistance for GRPU substrate according to claim 1, characterized in that: The trifluoroether water-based fluorocarbon resin has a fluorine content of ≥13%.

3. The water-based fluorocarbon paint with strong adhesion and high weather resistance for GRPU substrate according to claim 1, characterized in that: The organosilicon-modified isocyanate trimer curing agent is the product Wanhua Aquolin 280 curing agent.

4. The water-based fluorocarbon paint with strong adhesion and high weather resistance for GRPU substrate according to claim 1, characterized in that: The silane coupling agent is y-glycidyloxypropyltrimethoxysilane.

5. The water-based fluorocarbon paint with strong adhesion and high weather resistance for GRPU substrate according to claim 1, characterized in that: The weight ratio of component A to component B is (5.8-6.2):

1.

6. A method for preparing a water-based fluorocarbon paint with strong adhesion and high weather resistance for GRPU substrate according to any one of claims 1 to 5, characterized in that: The following steps are involved: S1. Mix a dispersant and water, add a filler and stir to obtain a dispersion slurry; mix a trifluoroether water-based fluorocarbon resin, a solvent and a dispersion slurry, stir to mix, and adjust the pH to 7.5-8.5 to obtain component A; S2, blending the diluent and the silane coupling agent, adding the isocyanate curing agent and stirring and mixing to obtain component B; S3, mix component A and component B to obtain.

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