A solvent-free epoxy coating and preparation method thereof

Abstract

The invention relates to the field of coatings, and in particular to a solvent-free epoxy coating and a preparation method thereof, wherein the coating comprises an A component and a B component; the A component comprises: 40-60 parts of epoxy resin, 5-20 parts of active diluent, 1-2 parts of dispersant, 0.5-2 parts of thixotropic agent, 0.5-2 parts of defoaming agent, 30-40 parts of pigment and filler, 1-2 parts of silane coupling agent, and 0.5-2 parts of leveling agent; the epoxy resin comprises bisphenol A type epoxy resin and bisphenol F type epoxy resin; the active diluent comprises alkyl glycidyl ether and aliphatic polyether polyol; the mass ratio of alkyl glycidyl ether and aliphatic polyether polyol is 1:1; the B component comprises: modified alicyclic amine and 4-(aminomethyl) octane-1,8-diamine, and the mass ratio of the modified alicyclic amine to the 4-(aminomethyl) octane-1,8-diamine is (5.5-10):1. The coating has excellent mechanical and corrosion resistance.

Description

Technical Field

[0001] The invention relates to the field of coatings, and in particular to a solvent-free epoxy coating and a preparation method thereof. Background Art

[0002] Solvent-free epoxy coatings have attracted much attention in the coatings field due to their excellent environmental performance, high film thickness after single spraying, and wide range of applications. However, there are still some problems in the application process. For example, due to the high viscosity of solvent-free epoxy coatings, high requirements are placed on construction equipment and processes. Special equipment, such as thermal spraying or double-mouth spray gun spraying, is required during construction. There are also high requirements for the operating skills and experience of construction personnel. Because it is difficult to reduce the viscosity of solvent-free epoxy coatings during construction, they are often suitable for thick coatings. The coatings generally have high brittleness, poor impact resistance and cracking resistance, and poor corrosion resistance and durability due to poor adhesion.

[0003] The prior art has improved some properties of solvent-free epoxy coatings by improving the composition of the coating. For example, by adding phenyl glycidyl ether (PGE) and benzyl glycidyl ether, the system viscosity of the solvent-free epoxy coating is reduced and the coating adhesion is increased, but the corrosion resistance and durability of the coating are not effectively improved. Adding alicyclic amine modified curing agent JH-0315 increases the chemical corrosion resistance and durability of the coating, but does not significantly improve the mechanical properties of the coating. Therefore, although the prior art improves the performance of solvent-free epoxy coatings by regulating the composition of the coating, there is still a problem that solvent-free epoxy coatings cannot meet both high mechanical strength and durability. Summary of the invention

[0004] Therefore, the technical problem to be solved by the present invention is to overcome the defects of the solvent-free epoxy coating in the prior art, such as poor viscosity, poor mechanical properties, corrosion resistance and durability, and inconvenient construction, thereby providing a solvent-free epoxy coating with low viscosity, high adhesion, quick drying, high toughness, impact resistance, acid and alkali resistance, salt spray resistance, and convenient construction, and a preparation method thereof.

[0005] To solve the above problems:

[0006] The present invention provides a solvent-free epoxy coating, comprising component A and component B;

[0007] The component A comprises the following raw materials in parts by weight: 40-60 parts of epoxy resin, 5-20 parts of active diluent, 1-2 parts of dispersant, 0.5-2 parts of thixotropic agent, 0.5-2 parts of defoaming agent, 30-40 parts of pigment and filler, 1-2 parts of silane coupling agent, and 0.5-2 parts of leveling agent;

[0008] The epoxy resin includes bisphenol A epoxy resin and bisphenol F epoxy resin;

[0009] The active diluent comprises alkyl glycidyl ether and aliphatic polyether polyol; the mass ratio of the alkyl glycidyl ether to the aliphatic polyether polyol is 1:1;

[0010] The B component includes: modified alicyclic amine and 4-(aminomethyl)octane-1,8-diamine, and the mass ratio of the modified alicyclic amine to 4-(aminomethyl)octane-1,8-diamine is (5.5-10):1.

[0011] Preferably, the mass ratio of component A to component B is (4-8):1;

[0012] The A component comprises the following raw materials in parts by weight:

[0013] Epoxy resin 50-60 parts, active diluent 10-20 parts, dispersant 1-1.5 parts, thixotropic agent 1.5-2 parts, defoamer 1.5-2 parts, pigment and filler 30-40 parts, silane coupling agent 1.5-2 parts, leveling agent 0.5-1 parts;

[0014] The B component includes: modified alicyclic amine and 4-(aminomethyl)octane-1,8-diamine, and the mass ratio of the modified alicyclic amine to 4-(aminomethyl)octane-1,8-diamine is (8-10):1.

[0015] Preferably, the alkyl glycidyl ether includes one or more of 1,6-hexanediol diglycidyl ether, 1,4-butanediol diglycidyl ether and ethylene glycol diglycidyl ether; and the aliphatic polyether polyol includes one or more of WANOL S3007, WANOL C2004 and WANOL C2010D.

[0016] When there are two types of alkyl glycidyl ethers, the mass ratio of the two is 1: 1. For example, when the alkyl glycidyl ethers are 1,4-butanediol diglycidyl ether and ethylene glycol diglycidyl ether, the mass ratio of 1,4-butanediol diglycidyl ether and ethylene glycol diglycidyl ether is 1:1.

[0017] In an optional embodiment, the viscosity of the aliphatic polyether polyol is less than 500 mPa·s. The viscosity of the aliphatic polyether polyol affects the fluidity, curing speed and curing effect of the coating.

[0018] In an optional embodiment, the hydroxyl content of the aliphatic polyether polyol is 3%-9%. The hydroxyl content of the aliphatic polyether polyol affects the adhesion of the coating. When the hydroxyl content is 3%-9%, the aliphatic polyether polyol can improve the fluidity, wettability and adhesion of the solvent-free epoxy coating, thereby improving the construction performance and film-forming quality of the coating. The present invention uses an aliphatic polyether polyol with a hydroxyl content of 3%-9%, and the adhesion of the solvent-free epoxy coating can reach 16.3-17MPa.

[0019] Preferably, the modified alicyclic amine includes one or more of WSG-228, BS-1445, WZH-155K and MFA-50.

[0020] In an optional embodiment, the amine value of the modified alicyclic amine can be selected to be 360-550 mgKOH / g. The higher the amine value of the modified alicyclic amine, the stronger the reactivity of the modified alicyclic amine with the epoxy resin, the faster the curing speed, and the higher the production efficiency. However, too high an amine value may cause the curing speed to be too fast, which is difficult to control and may even cause coating defects such as sagging and bubbles; the lower the amine value of the modified alicyclic amine, the slower the reaction rate with the epoxy resin, which is conducive to forming a more complete cross-linked network structure. However, too slow a curing rate prolongs the production cycle and reduces production efficiency.

[0021] Preferably, the mass ratio of the bisphenol A epoxy resin to the bisphenol F epoxy resin is (1-2):1; the bisphenol A epoxy resin includes one or more of E-51, Epon Resin 828 and DER 331; the bisphenol F epoxy resin includes one or more of NPEF-170, EPON-862, ARALDITE GY 285 and DER 354.

[0022] When there are two types of bisphenol A type epoxy resins, the mass ratio of the two is 1:2. For example, when the bisphenol A type epoxy resins are Epon Resin 828 and E-51, the mass ratio of Epon Resin 828 to E-51 is 1:2.

[0023] The epoxy equivalent of the bisphenol A epoxy resin described in the present invention can be selected as 160-200g / mol, and the epoxy equivalent of the bisphenol F epoxy resin can be selected as 160-200g / mol. The higher the epoxy equivalent of the epoxy resin, the longer the curing time and the lower the cross-linking density. Although the coating has certain flexibility and fluidity, due to the relatively low cross-linking density, the cross-linking structure is not tight enough, thereby reducing the heat resistance, mechanical strength, chemical corrosion resistance, etc. of the coating; the lower the epoxy equivalent of the epoxy resin, the higher the epoxy value, the more epoxy groups contained in the molecule, the faster the reaction rate with the curing agent, and the higher cross-linking density improves the heat resistance, mechanical strength and corrosion resistance of the coating. However, it will also increase the brittleness of the coating and reduce the impact resistance. The present invention has been found through research that when the epoxy equivalent of the epoxy resin is in the range of 160-200g / mol, it has a lower viscosity and a suitable epoxy value. The cured coating has a large cross-linking density, good corrosion resistance, strong heat resistance, and good mechanical strength and flexibility.

[0024] Preferably, the dispersant is a polyether active amine dispersant; the thixotropic agent includes one or more of polyamide wax, polyethylene wax, organic bentonite and hydrogenated castor oil; the defoamer is an organosilicon defoamer; and the leveling agent is an organically modified polyalkyl polysiloxane leveling agent.

[0025] When there are two types of thixotropic agents, the mass ratio of the two is 1: 1. For example, when the thixotropic agents are polyethylene wax and organic bentonite, the mass ratio of the polyethylene wax and the organic bentonite is 1:1.

[0026] Preferably, the polyether active amine dispersant includes D-156; the organosilicon defoamer includes one or more of EFKA SI2038, EFKA SI 2722, EFKA SI 2022, TEGO 900 and BYK-085; and the organically modified polyalkyl polysiloxane leveling agent includes AFCONA-3238.

[0027] When there are two types of silicone defoamers, the mass ratio of the two is 1: 1. For example, when the defoamers are EFKA SI 2722 and BYK-085, the mass ratio of EFKA SI 2722 and BYK-085 is 1:1.

[0028] Preferably, the color filler includes a pigment and a filler, and the mass ratio of the pigment to the filler is 1: (2-4); the pigment includes one or more of titanium dioxide, organic color pigments, carbon black, red iron oxide and yellow iron oxide, and the filler includes one or more of barium sulfate, talc, kaolin, mica powder and silica powder; the silane coupling agent includes one or more of KH-550, KH-560, KH-570 and KH-580.

[0029] In an optional embodiment, the organic color pigment includes one or more of phthalocyanine blue, organic orange, organic red and organic yellow.

[0030] The present invention also provides a method for preparing the solvent-free epoxy coating, comprising the following steps:

[0031] (1) mixing and stirring an epoxy resin, an alkyl glycidyl ether, a thixotropic agent, a dispersant and a defoaming agent to obtain a first mixture;

[0032] (2) adding pigments and fillers to the first mixed material, mixing and stirring, to obtain a second mixed material;

[0033] (3) adding a leveling agent and a silane coupling agent to the second mixture, mixing and stirring to obtain a third mixture, adding aliphatic polyether polyol, modified alicyclic amine and 4-(aminomethyl)octane-1,8-diamine to the third mixture, mixing evenly, and obtaining the solvent-free epoxy coating.

[0034] The specific steps in step (1) are: mixing and stirring the epoxy resin, alkyl glycidyl ether and thixotropic agent, stirring evenly, keeping the rotation speed unchanged, adding the dispersant, stirring evenly, adding the defoaming agent, stirring evenly, and obtaining a first mixture.

[0035] Preferably, the mixing and stirring speed in step (1) is 1000-2000 r / min; the mixing and stirring speed in step (2) is 2500-3000 r / min; the fineness of the second mixture in step (2) is less than 80 μm; the mixing and stirring speed in step (3) is 1000-2000 r / min.

[0036] The technical solution of the present invention has the following advantages:

[0037] 1. The present invention provides a solvent-free epoxy coating, comprising component A and component B, wherein component A comprises the following raw materials in parts by weight: 40-60 parts of epoxy resin, 5-20 parts of reactive diluent, 1-2 parts of dispersant, 0.5-2 parts of thixotropic agent, 0.5-2 parts of defoaming agent, 30-40 parts of pigments and fillers, 1-2 parts of silane coupling agent, and 0.5-2 parts of leveling agent;

[0038] The epoxy resin includes bisphenol A epoxy resin and bisphenol F epoxy resin; the active diluent includes alkyl glycidyl ether and aliphatic polyether polyol; the mass ratio of the alkyl glycidyl ether and the aliphatic polyether polyol is 1:1; the B component includes: modified alicyclic amine and 4-(aminomethyl)octane-1,8-diamine, and the mass ratio of the modified alicyclic amine to 4-(aminomethyl)octane-1,8-diamine is (5.5-10):1.

[0039] In the present invention, 4-(aminomethyl)octane-1,8-diamine and modified alicyclic amine are compounded into a curing agent, which can not only promote the rapid curing of epoxy resin after cross-linking reaction with epoxy resin, but also the cured coating has a large cross-linking density, good corrosion resistance, strong heat resistance, and good mechanical strength and flexibility. The addition of 4-(aminomethyl)octane-1,8-diamine also increases the adhesion to the metal substrate, making it easier to apply the coating evenly during the construction process, reducing bubbles, pinholes, and shedding, and improving the impact strength and corrosion resistance of the coating. In addition, the compounding of 4-(aminomethyl)octane-1,8-diamine and modified alicyclic amine can reduce the brittleness of the coating, reduce the internal stress of the coating to prevent cracking, and help extend the service life of the coating.

[0040] The epoxy groups in the epoxy resin react with the amine groups in the modified alicyclic amines by a ring-opening addition reaction. During the reaction, the epoxy groups open and combine with the amine groups to form new chemical bonds. As the reaction proceeds, a three-dimensional network structure gradually forms between the epoxy resin molecular chains. When there are more epoxy groups remaining in the epoxy resin, the epoxy groups are easy to react with water, acid or alkali in the environment, reducing the corrosion resistance and mechanical properties of the coating. When the modified alicyclic amine increases, the brittleness of the coating increases, the flexibility decreases, and the coating is prone to cracking. The cross-linking reaction between 4-(aminomethyl)octane-1,8-diamine with high amine value and epoxy resin is beneficial to increase the cross-linking density. Studies have found that the compounding of 4-(aminomethyl)octane-1,8-diamine and modified alicyclic amines can make up for the shortcomings of the modified alicyclic amines used alone, reduce the viscosity of the cured epoxy resin system, and facilitate construction and coating. Not only that, the compounding of the two can also enhance the curing effect and performance of the coating. The cross-linking reaction between epoxy resin and modified alicyclic amine and 4-(aminomethyl)octane-1,8-diamine molecules not only promotes the rapid curing of epoxy resin and improves construction efficiency, but also forms a more compact interpenetrating grid structure between molecular chains through cross-linking reaction, thereby improving the heat resistance and corrosion resistance of the coating. The synergistic effect of modified alicyclic amine and 4-(aminomethyl)octane-1,8-diamine enables the coating to have a higher elongation at break and impact strength while maintaining a certain tensile strength, further improving the fluidity and uniformity of the coating, helping to reduce defects and stress concentration inside the coating, improving the adhesion of the coating, and reducing the occurrence of bubbles, pinholes, and shedding in the coating. The cured coating has higher strength and toughness, reduces the brittleness of the coating, and reduces the aging and failure of the coating caused by environmental factors.

[0041] The active diluent of the present invention is a compound of alkyl glycidyl ether and aliphatic polyether polyol. Alkyl glycidyl ether can control the viscosity of the system, and aliphatic polyether polyol has low viscosity, good compatibility and good reactivity, and can improve the flexibility of the coating. The present invention has been found through research that the compounding of alkyl glycidyl ether and aliphatic polyether polyol has a synergistic effect. Not only can the compatibility of the epoxy resin matrix be improved, the viscosity of the system can be better reduced, and it has good workability, but also the flexibility and impact resistance of the cured product can be improved by introducing a flexible segment, the adhesion of the coating is significantly improved, the brittleness of the coating is reduced, and the durability and service life of the coating are improved. In addition, the high-activity epoxy group of the alkyl glycidyl ether and the hydroxyl group of the aliphatic polyether polyol effectively improve the adhesion of the coating, thereby improving the mechanical strength, heat resistance and chemical corrosion resistance of the cured product.

[0042] At the same time, the mass ratio of alkyl glycidyl ether to aliphatic polyether polyol is limited to 1: 1. Although both alkyl glycidyl ether and aliphatic polyether polyol can improve the workability of the coating, the amount of the two after compounding has a great influence on the performance of the coating, and changes in the amount of any component will affect the performance of the coating.

[0043] In the solvent-free epoxy coating provided by the present invention, the epoxy resin is a compound of bisphenol A epoxy resin and bisphenol F epoxy resin. The heat resistance of bisphenol F epoxy resin is lower than that of bisphenol A epoxy resin, but bisphenol F epoxy resin is superior to bisphenol A epoxy resin in terms of corrosion resistance. After the two are compounded, the heat resistance and corrosion resistance of the coating are not only improved through synergistic effect, but the compounded epoxy resin also has better adhesion and hardness. The improvement of mechanical properties makes it suitable for coating of various substrates.

[0044] 2. The present invention further limits the mass ratio of bisphenol A epoxy resin to bisphenol F epoxy resin to (1-2): 1. The present invention can reduce the cost of raw materials, shorten the curing time, and improve production efficiency and product economy by regulating the mass ratio of bisphenol A epoxy resin to bisphenol F epoxy resin while ensuring performance.

[0045] 3. The present invention further defines the dispersant as a polyether active amine dispersant. The polyether active amine dispersant has a relatively low viscosity. The coexistence of the polyether chain and the amino functional group can not only effectively reduce the interfacial tension between the pigment and the resin, but also make the pigment uniformly dispersed in the coating system, prevent the aggregation and precipitation of the pigment particles, and ensure the stability and uniformity of the coating, but also enable the coating to form a dense coating film structure, effectively block the erosion of chemical substances, and improve the chemical corrosion resistance of the coating.

[0046] The present invention further defines the leveling agent as an organically modified polyalkyl polysiloxane leveling agent. The organically modified polyalkyl polysiloxane leveling agent has good compatibility with epoxy resin, can be stably present in the coating system, reduce the surface tension of the coating, help the coating to form a more uniform and smooth coating film on the substrate, eliminate defects such as orange peel and shrinkage cavities on the coating surface, improve the appearance quality of the coating, enhance the adhesion of the coating film, and ensure that the coating film can be firmly attached to the substrate.

[0047] 4. The present invention also provides a method for preparing the solvent-free epoxy coating, comprising the following steps: (1) mixing epoxy resin, alkyl glycidyl ether, thixotropic agent, dispersant and defoaming agent to obtain a first mixture; (2) adding pigments and fillers to the first mixture, mixing and stirring to obtain a second mixture; (3) adding leveling agent and silane coupling agent to the second mixture, mixing and stirring to obtain a third mixture, adding aliphatic polyether polyol, modified alicyclic amine and 4-(aminomethyl)octane-1,8-diamine to the third mixture, mixing evenly, to obtain the solvent-free epoxy coating.

[0048] In the present invention, the aliphatic polyether polyol is added during the curing agent addition stage (component B), which can improve the efficiency and effect of the curing reaction and enhance the adhesion between the coating and the substrate. DETAILED DESCRIPTION

[0049] The following examples are provided for a better understanding of the present invention, but are not intended to limit the best mode of implementation, nor to limit the content and protection scope of the present invention. Any product identical or similar to the present invention obtained by anyone under the inspiration of the present invention or by combining the features of the present invention with other prior arts shall fall within the protection scope of the present invention.

[0050] If no specific experimental steps or conditions are specified in the examples, the conventional experimental steps or conditions described in the literature in the field can be used. If no manufacturer is specified for the reagents or instruments used, they are all conventional reagent products that can be obtained commercially.

[0051] Example 1

[0052] This embodiment provides a solvent-free epoxy coating, including component A and component B:

[0053] Raw materials of component A: 20kg bisphenol A epoxy resin E-51, 20kg bisphenol F epoxy resin DER 354, 2.5kg 1,6-hexanediol diglycidyl ether, 1.5kg thixotropic agent hydrogenated castor oil, 1kg polyether active amine dispersant D-156, 0.5kg silicone defoamer EFKA SI 2038, 10kg pigment titanium dioxide, 20kg filler barium sulfate, 0.5kg organic modified polyalkyl polysiloxane leveling agent AFCONA-3238, 1kg silane coupling agent KH-550, 2.5kg aliphatic polyether polyol WANOLC2004.

[0054] Raw materials for component B: 9 kg modified alicyclic amine BS-1445, 1 kg 4-(aminomethyl)octane-1,8-diamine.

[0055] The preparation method of the above-mentioned solvent-free epoxy coating comprises the following steps:

[0056] (1) Add 20 kg of E-51, 20 kg of DER 354, 2.5 kg of 1,6-hexanediol diglycidyl ether and 1.5 kg of hydrogenated castor oil into a dispersion tank, control the speed to 1000 r / min, mix and stir, and after stirring evenly, keep the speed unchanged, add 1 kg of D-156, stir evenly, add 0.5 kg of EFKA SI 2038, stir evenly, and obtain a first mixed material;

[0057] (2) Add 10 kg of titanium dioxide and 20 kg of barium sulfate to the first mixture, adjust the rotation speed to 2500 r / min, mix and stir to obtain a second mixture, and control the fineness of the second mixture to be less than 80 μm;

[0058] (3) Add 0.5 kg AFCONA-3238 and 1 kg KH-550 to the second mixture, control the rotation speed to 1000 r / min, mix and stir to obtain a third mixture, add 2.5 kg WANOL C2004, 9 kg BS-1445 and 1 kg 4-(aminomethyl)octane-1,8-diamine to the third mixture, mix well, and obtain the solvent-free epoxy coating.

[0059] Example 2

[0060] This embodiment provides a solvent-free epoxy coating, including component A and component B:

[0061] Raw materials of component A: 10kg bisphenol A epoxy resin Epon Resin 828, 20kg bisphenol A epoxy resin E-51, 20kg bisphenol F epoxy resin NPEF-170, 5kg 1,6-hexanediol diglycidyl ether, 0.5kg thixotropic agent polyamide wax, 1.5kg polyether active amine dispersant D-156, 1.5kg silicone defoamer EFKA SI 2022, 8kg pigment carbon black, 32kg filler talc, 1kg organic modified polyalkyl polysiloxane leveling agent AFCONA-3238, 1.5kg silane coupling agent KH-560, 5kg aliphatic polyether polyol WANOL S3007.

[0062] Raw materials for component B: 15 kg modified alicyclic amine WSG-228 and 1.5 kg 4-(aminomethyl)octane-1,8-diamine.

[0063] The preparation method of the above-mentioned solvent-free epoxy coating comprises the following steps:

[0064] (1) Add 10 kg of Epon Resin 828, 20 kg of E-51, 20 kg of NPEF-170, 5 kg of 1,6-hexanediol diglycidyl ether and 0.5 kg of polyamide wax into a dispersion tank, control the speed to 2000 r / min, mix and stir, and after stirring evenly, keep the speed unchanged, add 1.5 kg of D-156, stir evenly, add 1.5 kg of EFKA SI 2022, stir evenly, and obtain a first mixture;

[0065] (2) Add 8 kg of carbon black and 32 kg of talcum powder to the first mixture, adjust the speed to 3000 r / min, mix and stir to obtain a second mixture, and control the fineness of the second mixture to be less than 80 μm;

[0066] (3) Add 1 kg AFCONA-3238 and 1.5 kg KH-560 to the second mixture, control the rotation speed to 2000 r / min, mix and stir to obtain a third mixture, add 5 kg WANOL S3007, 15 kg WSG-228 and 1.5 kg 4-(aminomethyl)octane-1,8-diamine to the third mixture, mix well, and obtain the solvent-free epoxy coating.

[0067] Example 3

[0068] This embodiment provides a solvent-free epoxy coating, including component A and component B:

[0069] Raw materials of component A: 40kg bisphenol A epoxy resin Epon Resin 828, 10kg bisphenol F epoxy resin DER354, 10kg bisphenol F epoxy resin EPON-862, 5kg 1,4-butanediol diglycidyl ether, 0.5kg thixotropic agent polyethylene wax, 0.5kg thixotropic agent organic bentonite, 2kg polyether active amine dispersant D-156, 0.5kg silicone defoamer EFKASI 2722, 0.5kg silicone defoamer BYK-085, 10kg pigment iron oxide red, 30kg filler kaolin, 2kg organic modified polyalkyl polysiloxane leveling agent AFCONA-3238, 2kg silane coupling agent KH-570, 5kg aliphatic polyether polyol WANOL C2010D.

[0070] Raw materials for component B: 25 kg modified alicyclic amine WZH-155K and 4.5 kg 4-(aminomethyl)octane-1,8-diamine.

[0071] The preparation method of the above-mentioned solvent-free epoxy coating comprises the following steps:

[0072] (1) Add 40 kg of Epon Resin 828, 10 kg of DER 354, 10 kg of EPON-862, 5 kg of 1,4-butanediol diglycidyl ether, 0.5 kg of polyethylene wax, and 0.5 kg of organic bentonite into a dispersion tank, control the speed to 1500 r / min, mix and stir, and after stirring evenly, keep the speed unchanged, add 2 kg of D-156, stir evenly, add 0.5 kg of EFKA SI 2722 and 0.5 kg of BYK-085, stir evenly, and obtain a first mixture;

[0073] (2) Add 10 kg of red iron oxide and 30 kg of kaolin to the first mixture, adjust the rotation speed to 2800 r / min, mix and stir to obtain a second mixture, and control the fineness of the second mixture to be less than 80 μm;

[0074] (3) Add 2 kg of AFCONA-3238 and 2 kg of KH-570 to the second mixture, control the rotation speed to 1500 r / min, mix and stir to obtain a third mixture, add 5 kg of WANOL C2010D, 25 kg of WZH-155K and 4.5 kg of 4-(aminomethyl)octane-1,8-diamine to the third mixture, mix well, and obtain the solvent-free epoxy coating.

[0075] Example 4

[0076] This embodiment provides a solvent-free epoxy coating, including component A and component B:

[0077] Raw materials of component A: 30kg bisphenol A epoxy resin DER 331, 30kg bisphenol F epoxy resin ARALDITE GY285, 5kg 1,4-butanediol diglycidyl ether, 5kg ethylene glycol diglycidyl ether, 2kg thixotropic agent polyethylene wax, 1kg polyether active amine dispersant D-156, 2kg silicone defoamer TEGO 900, 10kg pigment phthalocyanine blue, 20kg filler mica powder, 1kg organic modified polyalkyl polysiloxane leveling agent AFCONA-3238, 2kg silane coupling agent KH-580, 5kg aliphatic polyether polyol WANOL S3007, 5kg aliphatic polyether polyol WANOL C2010D.

[0078] Raw materials of component B: 12 ​​kg modified alicyclic amine MFA-50, 12 kg modified alicyclic amine WZH-155K and 3 kg 4-(aminomethyl)octane-1,8-diamine.

[0079] The preparation method of the above-mentioned solvent-free epoxy coating comprises the following steps:

[0080] (1) Add 30 kg DER 331, 30 kg ARALDITE GY 285, 5 kg 1,4-butanediol diglycidyl ether, 5 kg ethylene glycol diglycidyl ether and 2 kg polyethylene wax into a dispersion tank, control the speed to 1800 r / min, mix and stir, and after stirring evenly, keep the speed unchanged, add 1 kg D-156, stir evenly, add 2 kg TEGO 900, stir evenly, and obtain a first mixture;

[0081] (2) Add 10 kg of phthalocyanine blue and 20 kg of mica powder to the first mixture, adjust the rotation speed to 2600 r / min, mix and stir to obtain a second mixture, and control the fineness of the second mixture to be less than 80 μm;

[0082] (3) Add 1 kg AFCONA-3238 and 2 kg KH-580 to the second mixture, control the rotation speed to 1800 r / min, mix and stir to obtain a third mixture, add 5 kg WANOL S3007, 5 kg WANOL C2010D, 12 kg MFA-50, 12 kg WZH-155K and 3 kg 4-(aminomethyl)octane-1,8-diamine to the third mixture, mix well, and obtain the solvent-free epoxy coating.

[0083] Comparative Example 1

[0084] This comparative example provides a solvent-free epoxy coating, including component A and component B:

[0085] Raw materials of component A: 50kg bisphenol A epoxy resin E-51, 10kg 1,6-hexanediol diglycidyl ether, 0.5kg thixotropic agent polyamide wax, 1.5kg polyether active amine dispersant D-156, 1.5kg silicone defoamer EFKA SI 2022, 8kg pigment carbon black, 32kg filler talc, 1kg organic modified polyalkyl polysiloxane leveling agent AFCONA-3238, 1.5kg silane coupling agent KH-560.

[0086] Raw materials for component B: 16.5 kg modified alicyclic amine WSG-228.

[0087] The preparation method of the above-mentioned solvent-free epoxy coating comprises the following steps:

[0088] (1) Add 50 kg of E-51, 10 kg of 1,6-hexanediol diglycidyl ether and 0.5 kg of polyamide wax into a dispersion tank, control the speed to 2000 r / min, mix and stir, and after stirring evenly, keep the speed unchanged, add 1.5 kg of D-156, stir evenly, add 1.5 kg of EFKA SI 2022, stir evenly, and obtain a first mixture;

[0089] (2) Add 8 kg of carbon black and 32 kg of talcum powder to the first mixture, adjust the speed to 3000 r / min, mix and stir to obtain a second mixture, and control the fineness of the second mixture to be less than 80 μm;

[0090] (3) Add 1 kg of AFCONA-3238 and 1.5 kg of KH-560 to the second mixture, control the rotation speed to 2000 r / min, mix and stir to obtain a third mixture, add 16.5 kg of modified alicyclic amine WSG-228 to the third mixture, mix evenly, and obtain the solvent-free epoxy coating.

[0091] Comparative Example 2

[0092] This comparative example provides a solvent-free epoxy coating, which differs from Example 2 in that aliphatic polyether polyol WANOL S3007 is not added, and the amount of 1,6-hexanediol diglycidyl ether used is 10 kg.

[0093] Comparative Example 3

[0094] This comparative example provides a solvent-free epoxy coating, which is different from Example 2 in that the amount of 1,6-hexanediol diglycidyl ether used is 1 kg, and the amount of aliphatic polyether polyol WANOL S3007 used is 9 kg.

[0095] Comparative Example 4

[0096] This comparative example provides a solvent-free epoxy coating, which differs from Example 2 in that bisphenol A epoxy resins Epon Resin 828 and E-51 are not added, and the amount of bisphenol F epoxy resin NPEF-170 used is 50 kg.

[0097] Comparative Example 5

[0098] This comparative example provides a solvent-free epoxy coating, which differs from Example 2 in that 4-(aminomethyl)octane-1,8-diamine and modified alicyclic amine WSG-228 are not added, and 16.5 kg of modified alicyclic amine JH-0315 is added.

[0099] Comparative Example 6

[0100] This comparative example provides a solvent-free epoxy coating, which differs from Example 2 in that 4-(aminomethyl)octane-1,8-diamine is replaced by an equal mass of 1,2,3-propylenetriamine.

[0101] Test Case

[0102] The solvent-free epoxy coatings obtained in the above examples and comparative examples were subjected to performance tests, wherein the performance test methods and indicators are shown in Table 1:

[0103] Table 1 Test methods and indicators for performance of solvent-free epoxy coatings

[0104]

[0105] According to the standards in Table 1, the solvent-free epoxy coatings prepared in Examples 1-4 and Comparative Examples 1-6 were tested, and the test results are shown in Table 2:

[0106] Table 2 Performance test results of Examples 1-4 and Comparative Examples 1-6

[0107]

[0108] It can be seen from Table 2 that the various properties of the solvent-free epoxy coating provided by the present invention meet the national standards.

[0109] In Example 2, compared with Comparative Example 1, bisphenol F epoxy resin is compounded with bisphenol A epoxy resin, and 4-(aminomethyl)octane-1,8-diamine is compounded with modified alicyclic amine WSG-228, which improves the adhesion of the solvent-free epoxy coating and enhances the flexibility, impact resistance, heat resistance, water resistance, corrosion resistance and other properties of the coating.

[0110] Compared with Comparative Example 2, the active diluent in Example 2 is compounded by aliphatic polyether polyol and alkyl glycidyl ether to improve the viscosity of the epoxy resin, enhance the flexibility of the coating, increase the impact resistance of the coating, effectively improve the adhesion of the coating, and improve the corrosion resistance of the coating.

[0111] Compared with Comparative Example 3, Example 2 affects the surface drying time, impact resistance, adhesion, flexibility, heat resistance, chemical corrosion resistance and other properties after changing the mass ratio of alkyl glycidyl ether to aliphatic polyether polyol.

[0112] In Example 2, compared with Comparative Example 4, the compounding of bisphenol F epoxy resin and bisphenol A epoxy resin not only further improves the heat resistance and corrosion resistance of the coating through synergistic effect, but also further improves the adhesion and hardness of the coating, thereby increasing the applicability of the coating.

[0113] Compared with Comparative Examples 5 and 6, Example 2 shows that the modified alicyclic amine is compounded with 4-(aminomethyl)octane-1,8-diamine, which can effectively improve the surface drying rate, adhesion, impact resistance, flexibility, heat resistance, water resistance and corrosion resistance of the solvent-free epoxy coating.

[0114] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention.

Claims

1. A solvent-free epoxy coating, characterized in that: It includes component A and component B; The component A comprises the following raw materials in parts by weight: 40-60 parts of epoxy resin, 5-20 parts of active diluent, 1-2 parts of dispersant, 0.5-2 parts of thixotropic agent, 0.5-2 parts of defoaming agent, 30-40 parts of pigment and filler, 1-2 parts of silane coupling agent, and 0.5-2 parts of leveling agent; The epoxy resin includes bisphenol A epoxy resin and bisphenol F epoxy resin; The reactive diluent includes alkyl glycidyl ether and aliphatic polyether polyol; The mass ratio of the alkyl glycidyl ether to the aliphatic polyether polyol is 1:1; The B component includes: modified alicyclic amine and 4-(aminomethyl)octane-1,8-diamine, and the mass ratio of the modified alicyclic amine to 4-(aminomethyl)octane-1,8-diamine is (5.5-10):

1.

2. The solvent-free epoxy coating according to claim 1, characterized in that: The mass ratio of component A to component B is (4-8):1; The component A comprises the following raw materials in parts by weight: 50-60 parts of epoxy resin, 10-20 parts of active diluent, 1-1.5 parts of dispersant, 1.5-2 parts of thixotropic agent, 1.5-2 parts of defoaming agent, 30-40 parts of pigment and filler, 1.5-2 parts of silane coupling agent, and 0.5-1 parts of leveling agent; The B component includes: modified alicyclic amine and 4-(aminomethyl)octane-1,8-diamine, and the mass ratio of the modified alicyclic amine to 4-(aminomethyl)octane-1,8-diamine is (8-10):

1.

3. The solvent-free epoxy coating according to claim 1, characterized in that: The alkyl glycidyl ether includes one or more of 1,6-hexanediol diglycidyl ether, 1,4-butanediol diglycidyl ether and ethylene glycol diglycidyl ether; The aliphatic polyether polyol includes one or more of WANOL S3007, WANOL C2004 and WANOL C2010D.

4. The solvent-free epoxy coating according to claim 1, characterized in that: The modified alicyclic amine includes one or more of WSG-228, BS-1445, WZH-155K and MFA-50.

5. The solvent-free epoxy coating according to claim 1 or 2, characterized in that: The mass ratio of the bisphenol A epoxy resin to the bisphenol F epoxy resin is (1-2): 1; The bisphenol A type epoxy resin includes one or more of E-51, Epon Resin 828 and DER 331; The bisphenol F type epoxy resin includes one or more of NPEF-170, EPON-862, ARALDITE GY 285 and DER 354.

6. The solvent-free epoxy coating according to claim 1, characterized in that: The dispersant is a polyether active amine dispersant; The thixotropic agent includes one or more of polyamide wax, polyethylene wax, organic bentonite and hydrogenated castor oil; The defoamer is a silicone defoamer; The leveling agent is an organically modified polyalkyl polysiloxane leveling agent.

7. The solvent-free epoxy coating according to claim 6, characterized in that: The polyether active amine dispersant includes D-156; The organosilicon defoamer includes one or more of EFKA SI 2038, EFKA SI 2722, EFKA SI 2022, TEGO 900 and BYK-085; The organically modified polyalkyl polysiloxane leveling agent includes AFCONA-3238.

8. The solvent-free epoxy coating according to claim 1, characterized in that: The color filler comprises a pigment and a filler, and the mass ratio of the pigment to the filler is 1:(2-4); The pigment includes one or more of titanium dioxide, organic color pigment, carbon black, red iron oxide and yellow iron oxide, and the filler includes one or more of barium sulfate, talc, kaolin, mica powder and silica powder; The silane coupling agent includes one or more of KH-550, KH-560, KH-570 and KH-580.

9. The method for preparing the solvent-free epoxy coating according to any one of claims 1 to 8, characterized in that: It includes the following steps: (1) mixing and stirring an epoxy resin, an alkyl glycidyl ether, a thixotropic agent, a dispersant and a defoaming agent to obtain a first mixed material; (2) adding pigments and fillers to the first mixed material, mixing and stirring, to obtain a second mixed material; (3) adding a leveling agent and a silane coupling agent to the second mixture, mixing and stirring to obtain a third mixture, adding aliphatic polyether polyol, modified alicyclic amine and 4-(aminomethyl)octane-1,8-diamine to the third mixture, mixing evenly, and obtaining the solvent-free epoxy coating.

10. The method for preparing a solvent-free epoxy coating according to claim 9, characterized in that: The mixing and stirring speed in step (1) is 1000-2000 r / min; The mixing and stirring speed in step (2) is 2500-3000 r / min; The fineness of the second mixed material in step (2) is less than 80 μm; The rotation speed of the mixing and stirring in step (3) is 1000-2000 r / min.

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