A modified polyurea coating and its preparation method

Abstract

A modified polyurea coating and its preparation method, which relates to the technical field of coatings, includes component A and component B; Component A includes the following raw material components: functional polyurea, meso-tetramethyl-meso-tetra(p-aminophenyl)calix[4]pyrrole, initiator, auxiliary agent, catalyst A, solvent; Component B includes the following raw material components: isocyanatoethyl methacrylate, cage-like octasilsesquioxane containing epoxy groups and vinyl groups, 2,4,6-trivinylcyclotriboroxane, N-vinyl oxazolidinone; The functional polyurea includes the structural units introduced by the following monomers: diisocyanate polyethylene glycol, 2,2-bis[4-(4-aminophenoxy)phenyl]-1,1,1,3,3,3-hexafluoropropane, 3,3'-diamino-4,4'-difluorodiphenyl sulfone, 1,4-diamino-2,3-dicyanoanthraquinone. This coating has good bonding performance, sufficient mechanical and thermal properties, and excellent weather resistance.

Description

Technical Field

[0001] The invention relates to the technical field of coatings, and in particular to a modified polyurea coating and a preparation method thereof. Background Art

[0002] Polyurea coating is a pollution-free, high-performance, environmentally friendly material. It is a new type of material developed in recent years following environmentally friendly coatings such as high-solid coatings, water-based coatings, light-curing coatings and powder coatings. Due to its good wear resistance, impact resistance, green pollution-free and chemical corrosion resistance, it has been widely used in waterproofing and heavy-duty corrosion protection of entertainment facilities, high-speed railways, bridges, and marine engineering equipment.

[0003] Although polyurea coatings have good performance, they still have some defects and are difficult to meet certain overly demanding usage requirements. For example, most of the existing polyurea coatings have poor adhesion, poor waterproof performance and stain resistance, and insufficient weather resistance and temperature resistance. It is under this situation that modified polyurea coatings came into being, and its appearance has attracted widespread attention in the industry. However, the modified polyurea coatings on the market have more or less technical problems such as high cost, easy agglomeration of modifiers, poor performance stability, insufficient mechanical properties and temperature resistance, and weather resistance needs to be further improved.

[0004] In order to solve the above technical problems, a Chinese invention patent with the authorization announcement number CN109943207B discloses a modified polyurea coating, including component A and component B; the component A is spherical nanoparticles modified by silane with terminal amino groups; the component B is a diisocyanate compound. Compared with the prior art, the invention uses spherical nanoparticles modified by silane with terminal amino groups as component A, and can realize the liquefaction of nanoparticles by controlling the length and grafting surface density of the silane grafted chain with terminal amino groups, thereby ensuring the single uniform dispersion of nanoparticles when the components A and B are mixed, and also making the coating formed after the modified polyurea coating is cured have super high strength, hardness and wear resistance. However, its temperature resistance and weather resistance still need to be further improved.

[0005] It can be seen that the art still needs a modified polyurea coating with good bonding properties, sufficient mechanical properties and temperature resistance, and good weather resistance, and a preparation method thereof. Summary of the invention

[0006] In view of this, the technical problem to be solved by the present invention is to provide a modified polyurea coating with good bonding performance, sufficient mechanical properties and temperature resistance, and good weather resistance, and a preparation method thereof.

[0007] The present invention provides a modified polyurea coating, which comprises component A and component B; the mass ratio of component A to component B is 1:1; component A comprises the following raw materials by weight: 60-70 parts of functional polyurea, 3-5 parts of meso-tetramethyl-meso-tetra-p-aminophenylcalix[4]pyrrole, 0.8-1.2 parts of initiator, 0.5-3 parts of auxiliary agent, 1-2 parts of catalyst A, and 30-40 parts of solvent; component B comprises the following raw materials by weight: 4-6 parts of isocyanatoethyl methacrylate, 3-5 parts of cage-like octasilsesquioxane containing epoxy group and vinyl group, 2-4 parts of 2,4,6-trivinylcyclotriboroxane, and 1-3 parts of N-vinyl oxazolidinone; the structural units introduced by the following monomers are included in the functional polyurea: diisocyanate polyethylene glycol, 2,2-bis[4-(4-aminophenoxy)phenyl]-1,1,1,3,3,3-hexafluoropropane, 3,3'-diamino-4,4'-difluorodiphenyl sulfone, 1,4-diamino-2,3-dicyanoanthraquinone.

[0008] Preferably, the preparation method of the functional polyurea comprises the following steps: adding diisocyanate polyethylene glycol, 2,2-bis[4-(4-aminophenoxy)phenyl]-1,1,1,3,3,3-hexafluoropropane, 3,3'-diamino-4,4'-difluorodiphenyl sulfone, 1,4-diamino-2,3-dicyanoanthraquinone, and catalyst B into a high-boiling solvent, stirring and reacting at 75-90 °C for 2-4 hours under an inert gas atmosphere, then raising the temperature to 93-98 °C and continuing to stir and react for 8-15 hours, then precipitating in water, washing the precipitated polymer with ethanol 3-6 times, and then rotary evaporating to remove the residual solvent to obtain the functional polyurea.

[0009] Preferably, the diisocyanate polyethylene glycol is diisocyanate polyethylene glycol NCO-PEO-NCO, with a weight-average molecular weight of 400, provided by Guangdong Wengjiang Chemical Reagent Co., Ltd.

[0010] Preferably, the molar ratio of diisocyanate polyethylene glycol, 2,2-bis[4-(4-aminophenoxy)phenyl]-1,1,1,3,3,3-hexafluoropropane, 3,3'-diamino-4,4'-difluorodiphenyl sulfone, 1,4-diamino-2,3-dicyanoanthraquinone, catalyst B, and high-boiling solvent is 1:0.5:0.3:0.2:(0.8-1.2):(6-10).

[0011] Preferably, the high-boiling solvent is dimethyl sulfoxide; the catalyst B is at least one of dibutyltin dilaurate and stannous octoate; the inert gas is any one of nitrogen, helium, neon, and argon.

[0012] Preferably, the preparation method of the meso-tetramethyl-meso-tetraaminophenylcalix[4]pyrrole is described in: Guo Yong, Shao Shijun, He Lijun, et al. Synthesis and Characterization of Meso-tetramethyl-meso-tetraaminophenylcalix[4]pyrrole [J]. Chemical Reagents, 2002(6):344-345.

[0013] Preferably, the initiator is azobisisobutyronitrile.

[0014] Preferably, the auxiliary agent is a mixture of a dispersant, a leveling agent and a defoamer in a mass ratio of (1-2):1:(1-3).

[0015] Preferably, the dispersant is at least one of polycarboxylate dispersant 5040 and sodium hexametaphosphate; the defoamer is one or more of tributyl phosphate, defoamer Deqian 3100, and defoamer BYK088; the leveling agent is at least one of German BYK leveling agent BYK-333 and silicone leveling agent HY-5030.

[0016] Preferably, the catalyst A is at least one of dibutyltin dilaurate and stannous octoate.

[0017] Preferably, the solvent is any one of acetone, ethyl acetate, toluene and propylene glycol methyl ether.

[0018] Preferably, there is no special requirement for the source of the epoxy- and vinyl-containing cage-type silsesquioxane. In one embodiment of the present invention, the epoxy- and vinyl-containing cage-type silsesquioxane is prepared according to the preparation method of tetraepoxy cage-type silsesquioxane in Example 1 of the authorization publication number CN101508698B.

[0019] Another object of the present invention is to provide a method for preparing a modified polyurea coating, comprising the following steps:

[0020] Step S1, preparation of the component A: uniformly mixing the constituent raw materials of the component A to obtain the component A;

[0021] Step S2, preparation of the component B: uniformly mixing the raw materials of the component B to obtain the component B;

[0022] Step S3, mixing the component A and the component B in a mass ratio of 1:1, stirring evenly, to obtain a modified polyurea coating.

[0023] Due to the application of the above technical solution, the present invention has the following beneficial effects:

[0024] (1) The preparation method of the modified polyurea coating disclosed by the present invention only requires mixing each raw material evenly, without the need for special equipment, with less capital investment, low energy consumption, simple and easy-to-operate process, high preparation efficiency and high qualified product rate, being suitable for continuous large-scale production, and having high popularization and application value.

[0025] (2) The modified polyurea coating disclosed by the present invention includes component A and component B; the mass ratio of component A to component B is 1:1; component A includes the following raw materials by weight: 60 - 70 parts of functional polyurea, 3 - 5 parts of meso-tetramethyl-meso-tetra(p-aminophenyl)calix[4]pyrrole, 0.8 - 1.2 parts of initiator, 0.5 - 3 parts of auxiliary agent, 1 - 2 parts of catalyst A, and 30 - 40 parts of solvent; component B includes the following raw materials by weight: 4 - 6 parts of isocyanatoethyl methacrylate, 3 - 5 parts of cage-like octasilsesquioxane containing epoxy groups and vinyl groups, 2 - 4 parts of 2,4,6-trivinylcyclotriboroxane, and 1 - 3 parts of N-vinyl oxazolidinone; the functional polyurea includes the structural units introduced by the following monomers: diisocyanate polyethylene glycol, 2,2-bis[4-(4-aminophenoxy)phenyl]-1,1,1,3,3,3-hexafluoropropane, 3,3'-diamino-4,4'-difluorodiphenyl sulfone, 1,4-diamino-2,3-dicyanoanthraquinone. Through the mutual cooperation and joint action of each component and the constituent raw materials, the modified polyurea coating product can be endowed with advantages such as good bonding performance, sufficient mechanical and thermal properties, and excellent weather resistance.

[0026] (3) For the modified polyurea coating disclosed by the present invention, the functional polyurea includes the structural units introduced by the following monomers: diisocyanate polyethylene glycol, 2,2-bis[4-(4-aminophenoxy)phenyl]-1,1,1,3,3,3-hexafluoropropane, 3,3'-diamino-4,4'-difluorodiphenyl sulfone, 1,4-diamino-2,3-dicyanoanthraquinone. Fluorinated phenyl ether, fluorinated diphenyl sulfone, dicyanoanthraquinone, and polyethylene glycol structures are simultaneously introduced into the main chain of the polyurea molecule to modify the polyurea, and ring boroxane and oxazolidinone structures are introduced into the molecular structure through other raw materials; under the multiple effects of electronic effect, steric effect, and conjugation effect, etc., the prepared modified polyurea coating has better bonding performance, more sufficient mechanical and thermal properties, and better weather resistance.

[0027] (4)The modified polyurea coating disclosed by the present invention is such that the isocyanate group on isocyanatoethyl methacrylate can react with raw materials containing amino groups; meanwhile, the unsaturated double bond thereon can also undergo copolymerization curing reaction with other raw materials containing unsaturated double bonds; the epoxy group on the cage-like silsesquioxane containing epoxy groups and vinyl groups can also undergo epoxy ring-opening reaction with raw materials containing amino groups, so that multiple interpenetrating network structures coexist in the formed coating film. The existence of these interpenetrating network structures can effectively improve the adhesion performance, mechanical properties, temperature resistance and weather resistance. Detailed implementation manners

[0028] The following description is used to disclose the present invention so that those skilled in the art can implement the present invention. The preferred embodiments in the following description are only examples, and other obvious variations can be conceived by those skilled in the art. Example 1

[0029] A modified polyurea coating, comprising component A and component B; the mass ratio of component A to component B is 1:1; component A comprises the following raw materials by weight: 60 parts of functional polyurea, 3 parts of meso-tetramethyl-meso-tetra-p-aminophenylcalix[4]pyrrole, 0.8 part of initiator, 0.5 part of auxiliary agent, 1 part of catalyst A, 30 parts of solvent; component B comprises the following raw materials by weight: 4 parts of isocyanatoethyl methacrylate, 3 parts of cage-like silsesquioxane containing epoxy groups and vinyl groups, 2 parts of 2,4,6-trivinylcyclotriboroxane, 1 part of N-vinyl oxazolidinone; the functional polyurea comprises the structural units introduced by the following monomers: diisocyanate polyethylene glycol, 2,2-bis[4-(4-aminophenoxy)phenyl]-1,1,1,3,3,3-hexafluoropropane, 3,3'-diamino-4,4'-difluorodiphenyl sulfone, 1,4-diamino-2,3-dicyanoanthraquinone.

[0030] The preparation method of the functional polyurea comprises the following steps: adding diisocyanate polyethylene glycol, 2,2-bis[4-(4-aminophenoxy)phenyl]-1,1,1,3,3,3-hexafluoropropane, 3,3'-diamino-4,4'-difluorodiphenyl sulfone, 1,4-diamino-2,3-dicyanoanthraquinone, and catalyst B into a high-boiling solvent, stirring and reacting at 75 °C for 2 hours under an inert gas atmosphere, then heating to 93 °C and continuing to stir and react for 8 hours, then precipitating in water, washing the precipitated polymer with ethanol 3 times, and then rotary evaporating to remove the residual solvent to obtain the functional polyurea; the diisocyanate polyethylene glycol is diisocyanate polyethylene glycol NCO-PEO-NCO with a weight-average molecular weight of 400, provided by Guangdong Wengjiang Chemical Reagent Co., Ltd.; the molar ratio of the diisocyanate polyethylene glycol, 2,2-bis[4-(4-aminophenoxy)phenyl]-1,1,1,3,3,3-hexafluoropropane, 3,3'-diamino-4,4'-difluorodiphenyl sulfone, 1,4-diamino-2,3-dicyanoanthraquinone, catalyst B, and high-boiling solvent is 1:0.5:0.3:0.2:0.8:6; the high-boiling solvent is dimethyl sulfoxide; the catalyst B is dibutyltin dilaurate; the inert gas is nitrogen. Through GPC testing, the M n of this functional polyurea was measured to be 14720 g / mol, and M W / M n = 1.361; through elemental analysis and weight change calculation, the molar ratio of the structural units introduced by the diisocyanate polyethylene glycol, 2,2-bis[4-(4-aminophenoxy)phenyl]-1,1,1,3,3,3-hexafluoropropane, 3,3'-diamino-4,4'-difluorodiphenyl sulfone, and 1,4-diamino-2,3-dicyanoanthraquinone in this functional polyurea is the same as the theoretical value.

[0031] For the preparation method of the Meso-tetramethyl-meso-tetra-p-aminophenylcalix[4]pyrrole, see: Guo Yong, Shao Shijun, He Lijun, et al. Synthesis and Characterization of Meso-tetramethyl-meso-tetra-p-aminophenylcalix[4]pyrrole [J]. Chemical Reagents, 2002(6):344-345; the initiator is azobisisobutyronitrile; the auxiliary agent is composed of a dispersant, a leveling agent, and an antifoaming agent mixed in a mass ratio of 1:1:1; the dispersant is polycarboxylate dispersant 5040; the antifoaming agent is tributyl phosphate; the leveling agent is BYK leveling agent BYK-333 from BYK of Germany; the catalyst A is dibutyltin dilaurate; the solvent is acetone; the epoxy group- and vinyl-containing cage-like sesquisiloxane is prepared according to the preparation method of tetra-epoxy cage-like sesquisiloxane in Example 1 of the authorized announcement number CN101508698B.

[0032] A preparation method of a modified polyurea coating comprises the following steps:

[0033] Step S1, preparation of the component A: After uniformly mixing the raw materials of the component A, the component A is obtained;

[0034] Step S2, preparation of the component B: After uniformly mixing the raw materials of the component B, the component B is obtained;

[0035] Step S3, mixing the component A and the component B according to a mass ratio of 1:1, and stirring evenly to obtain a modified polyurea coating. Example 2

[0036] A modified polyurea coating, comprising a component A and a component B; the mass ratio of the component A to the component B is 1:1; the component A comprises the following raw materials by weight: 63 parts of functional polyurea, 3.5 parts of meso-tetramethyl-meso-tetra-p-aminophenylcalix[4]pyrrole, 0.9 part of initiator, 1 part of auxiliary agent, 1.2 parts of catalyst A, 33 parts of solvent; the component B comprises the following raw materials by weight: 4.5 parts of isocyanatoethyl methacrylate, 3.5 parts of cage-like octasilsesquioxane containing epoxy groups and vinyl groups, 2.5 parts of 2,4,6-trivinylcyclotriboroxane, 1.5 parts of N-vinyl oxazolidinone; the functional polyurea comprises the structural units introduced by the following monomers: diisocyanate polyethylene glycol, 2,2-bis[4-(4-aminophenoxy)phenyl]-1,1,1,3,3,3-hexafluoropropane, 3,3'-diamino-4,4'-difluorodiphenyl sulfone, 1,4-diamino-2,3-dicyanoanthraquinone.

[0037] The preparation method of the functional polyurea comprises the following steps: adding diisocyanate polyethylene glycol, 2,2-bis[4-(4-aminophenoxy)phenyl]-1,1,1,3,3,3-hexafluoropropane, 3,3'-diamino-4,4'-difluorodiphenyl sulfone, 1,4-diamino-2,3-dicyanoanthraquinone, and catalyst B into a high-boiling solvent, stirring and reacting at 80 °C for 2.5 hours in an inert gas atmosphere, then raising the temperature to 95 °C and continuing to stir and react for 10 hours, then precipitating in water, washing the precipitated polymer with ethanol 4 times, and then rotary evaporating to remove the residual solvent to obtain the functional polyurea; the diisocyanate polyethylene glycol is diisocyanate polyethylene glycol NCO-PEO-NCO, with a weight-average molecular weight of 400, provided by Guangdong Wengjiang Chemical Reagent Co., Ltd.; the molar ratio of diisocyanate polyethylene glycol, 2,2-bis[4-(4-aminophenoxy)phenyl]-1,1,1,3,3,3-hexafluoropropane, 3,3'-diamino-4,4'-difluorodiphenyl sulfone, 1,4-diamino-2,3-dicyanoanthraquinone, catalyst B, and high-boiling solvent is 1:0.5:0.3:0.2:0.9:7; the high-boiling solvent is dimethyl sulfoxide; the catalyst B is stannous octoate; the inert gas is helium.

[0038] The preparation method of the meso-tetramethyl-meso-tetraaminophenyl cup [4] pyrrole is described in: Guo Yong, Shao Shijun, He Lijun, et al. Synthesis and Characterization of Meso-tetramethyl-meso-tetraaminophenyl cup [4] pyrrole [J]. Chemical Reagents, 2002 (6): 344-345; the initiator is azobisisobutyronitrile; the auxiliary agent is a dispersant, a leveling agent, and a defoaming agent mixed in a mass ratio of 1.2:1:1.5; the dispersant is sodium hexametaphosphate; the defoaming agent is defoaming agent Deqian 3100; the leveling agent is an organic silicone leveling agent HY-5030; the catalyst A is stannous octoate; the solvent is ethyl acetate; the epoxy- and vinyl-containing cage-type silsesquioxane is prepared according to the preparation method of tetraepoxy cage-type silsesquioxane in Example 1 of the authorization announcement number CN101508698B.

[0039] A method for preparing a modified polyurea coating comprises the following steps:

[0040] Step S1, preparation of the component A: uniformly mixing the constituent raw materials of the component A to obtain the component A;

[0041] Step S2, preparation of the component B: uniformly mixing the raw materials of the component B to obtain the component B;

[0042] Step S3, mixing the component A and the component B in a mass ratio of 1:1, stirring evenly, to obtain a modified polyurea coating. Example 3

[0043] A modified polyurea coating, comprising a component A and a component B; the mass ratio of the component A to the component B is 1:1; the component A comprises the following raw materials in parts by weight: 65 parts of functional polyurea, 4 parts of meso-tetramethyl-meso-tetra-p-aminophenyl cup [4] pyrrole, 1 part of initiator, 2 parts of auxiliary agent, and catalyst A 1.5 parts, and 35 parts of solvent; the component B includes the following raw materials in parts by weight: 5 parts of isocyanoethyl methacrylate, 4 parts of cage-type silsesquioxane containing epoxy and vinyl groups, 3 parts of 2,4,6-trivinyl cycloboroxine, and 2 parts of N-vinyl oxazolidinone; the functional polyurea includes structural units introduced by the following monomers: diisocyanate polyethylene glycol, 2,2-bis[4-(4-aminophenoxy)phenyl]-1,1,1,3,3,3-hexafluoropropane, 3,3'-diamino-4,4'-difluorodiphenyl sulfone, and 1,4-diamino-2,3-dicyanoanthraquinone.

[0044] The preparation method of the functional polyurea comprises the following steps: adding diisocyanate polyethylene glycol, 2,2-bis[4-(4-aminophenoxy)phenyl]-1,1,1,3,3,3-hexafluoropropane, 3,3'-diamino-4,4'-difluorodiphenyl sulfone, 1,4-diamino-2,3-dicyanoanthraquinone, and catalyst B into a high-boiling solvent, stirring and reacting at 83 °C for 3 hours under an inert gas atmosphere, then raising the temperature to 96 °C and continuing to stir and react for 12 hours, then precipitating in water, washing the precipitated polymer with ethanol 5 times, and then rotary evaporating to remove the residual solvent to obtain the functional polyurea; the diisocyanate polyethylene glycol is diisocyanate polyethylene glycol NCO-PEO-NCO with a weight-average molecular weight of 400, provided by Guangdong Wengjiang Chemical Reagent Co., Ltd.; the molar ratio of the diisocyanate polyethylene glycol, 2,2-bis[4-(4-aminophenoxy)phenyl]-1,1,1,3,3,3-hexafluoropropane, 3,3'-diamino-4,4'-difluorodiphenyl sulfone, 1,4-diamino-2,3-dicyanoanthraquinone, catalyst B, and high-boiling solvent is 1:0.5:0.3:0.2:1:8; the high-boiling solvent is dimethyl sulfoxide; the catalyst B is dibutyltin dilaurate; the inert gas is neon.

[0045] For the preparation method of the Meso-tetramethyl-meso-tetra-p-aminophenylcalix[4]pyrrole, see: Guo Yong, Shao Shijun, He Lijun, et al. Synthesis and Characterization of Meso-tetramethyl-meso-tetra-p-aminophenylcalix[4]pyrrole [J]. Chemical Reagents, 2002(6):344-345; the initiator is azobisisobutyronitrile; the auxiliary agent is composed of a dispersant, a leveling agent, and an antifoaming agent mixed in a mass ratio of 1.5:1:2; the dispersant is polycarboxylate dispersant 5040; the antifoaming agent is antifoaming agent BYK088; the leveling agent is BYK leveling agent BYK-333 from BYK of Germany; the catalyst A is dibutyltin dilaurate; the solvent is toluene; the epoxy group- and vinyl-containing cage-like silsesquioxane is prepared according to the preparation method of tetra-epoxy cage-like silsesquioxane in Example 1 of the authorized announcement number CN101508698B.

[0046] A preparation method of a modified polyurea coating comprises the following steps:

[0047] Step S1, preparation of the component A: After mixing the raw materials of the component A evenly, the component A is obtained;

[0048] Step S2, preparation of the component B: After mixing the raw materials of the component B evenly, the component B is obtained;

[0049] Step S3, mixing the component A and the component B according to a mass ratio of 1:1, stirring evenly, to obtain the modified polyurea coating. Example 4

[0050] A modified polyurea coating, comprising component A and component B; the mass ratio of component A to component B is 1:1; component A comprises the following raw materials by weight: 68 parts of functional polyurea, 4.5 parts of meso-tetramethyl-meso-tetra(p-aminophenyl)calix[4]pyrrole, 1.1 parts of initiator, 2.5 parts of auxiliary agent, 1.8 parts of catalyst A, and 38 parts of solvent; component B comprises the following raw materials by weight: 5.5 parts of isocyanatoethyl methacrylate, 4.5 parts of cage-like octasilsesquioxane containing epoxy groups and vinyl groups, 3.5 parts of 2,4,6-trivinylcyclotriboroxane, and 2.5 parts of N-vinyl oxazolidinone; the structural units introduced by the following monomers are included in the functional polyurea: diisocyanate polyethylene glycol, 2,2-bis[4-(4-aminophenoxy)phenyl]-1,1,1,3,3,3-hexafluoropropane, 3,3'-diamino-4,4'-difluorodiphenyl sulfone, 1,4-diamino-2,3-dicyanoanthraquinone.

[0051] The preparation method of the functional polyurea comprises the following steps: adding diisocyanate polyethylene glycol, 2,2-bis[4-(4-aminophenoxy)phenyl]-1,1,1,3,3,3-hexafluoropropane, 3,3'-diamino-4,4'-difluorodiphenyl sulfone, 1,4-diamino-2,3-dicyanoanthraquinone, and catalyst B into a high-boiling solvent, stirring and reacting at 87°C for 3.5 hours under an inert gas atmosphere, then raising the temperature to 97°C and continuing to stir and react for 14 hours, then precipitating in water, washing the precipitated polymer with ethanol 6 times, and then rotary evaporating to remove the residual solvent to obtain the functional polyurea; the diisocyanate polyethylene glycol is diisocyanate polyethylene glycol NCO-PEO-NCO, with a weight average molecular weight of 400, provided by Guangdong Wengjiang Chemical Reagent Co., Ltd.; the molar ratio of diisocyanate polyethylene glycol, 2,2-bis[4-(4-aminophenoxy)phenyl]-1,1,1,3,3,3-hexafluoropropane, 3,3'-diamino-4,4'-difluorodiphenyl sulfone, 1,4-diamino-2,3-dicyanoanthraquinone, catalyst B, and high-boiling solvent is 1:0.5:0.3:0.2:1.1:9.5; the high-boiling solvent is dimethyl sulfoxide; the catalyst B is a mixture of dibutyltin dilaurate and stannous octoate in a mass ratio of 3:5; the inert gas is argon.

[0052] The preparation method of Meso-tetramethyl-meso-tetraaminophenyl cup [4] pyrrole, see: Guo Yong, Shao Shijun, He Lijun, et al. Synthesis and Characterization of Meso-tetramethyl-meso-tetraaminophenyl cup [4] pyrrole [J]. Chemical Reagents, 2002 (6): 344-345; the initiator is azobisisobutyronitrile; the auxiliary agent is a mixture of a dispersant, a leveling agent, and a defoamer in a mass ratio of 1.8:1:2.5; the dispersant is a mixture of a polycarboxylate dispersant 5040 and sodium hexametaphosphate in a mass ratio of 1:2; the defoamer is tributyl phosphate, a defoamer Deqian 3100, a defoamer The foaming agent BYK088 is mixed in a mass ratio of 1:2:3; the leveling agent is a German BYK leveling agent BYK-333 and a silicone leveling agent HY-5030 mixed in a mass ratio of 2:1; the catalyst A is dibutyltin dilaurate; the solvent is propylene glycol methyl ether; the epoxy- and vinyl-containing cage-type silsesquioxane is prepared according to the preparation method of tetraepoxy cage-type silsesquioxane in Example 1 of the authorization announcement number CN101508698B.

[0053] A method for preparing a modified polyurea coating comprises the following steps:

[0054] Step S1, preparation of the component A: uniformly mixing the constituent raw materials of the component A to obtain the component A;

[0055] Step S2, preparation of the component B: uniformly mixing the raw materials of the component B to obtain the component B;

[0056] Step S3, mixing the component A and the component B in a mass ratio of 1:1, stirring evenly, to obtain a modified polyurea coating. Example 5

[0057] A modified polyurea coating, comprising a component A and a component B; the mass ratio of the component A to the component B is 1:1; the component A comprises the following raw materials in parts by weight: 70 parts of functional polyurea, 5 parts of meso-tetramethyl-meso-tetra-p-aminophenyl cup [4] pyrrole, 1.2 parts of initiator, 3 parts of auxiliary agent, and catalyst A 2 parts, 40 parts of solvent; the component B includes the following raw materials in parts by weight: 6 parts of isocyanoethyl methacrylate, 5 parts of cage-type silsesquioxane containing epoxy and vinyl groups, 4 parts of 2,4,6-trivinyl cycloboroxine, and 3 parts of N-vinyl oxazolidinone; the functional polyurea includes structural units introduced by the following monomers: diisocyanate polyethylene glycol, 2,2-bis[4-(4-aminophenoxy)phenyl]-1,1,1,3,3,3-hexafluoropropane, 3,3'-diamino-4,4'-difluorodiphenyl sulfone, and 1,4-diamino-2,3-dicyanoanthraquinone.

[0058] The preparation method of the functional polyurea comprises the following steps: adding diisocyanate polyethylene glycol, 2,2-bis[4-(4-aminophenoxy)phenyl]-1,1,1,3,3,3-hexafluoropropane, 3,3'-diamino-4,4'-difluorodiphenyl sulfone, 1,4-diamino-2,3-dicyanoanthraquinone and catalyst B into a high boiling point solvent, stirring and reacting for 4 hours at 90° C. in an inert gas atmosphere, then heating to 98° C. and continuing stirring and reacting for 15 hours, then precipitating in water, washing the precipitated polymer with ethanol for 6 times, and then rotary evaporating to remove the residual solvent to obtain the functional polyurea; the diisocyanate polyethylene glycol is diisocyanate polyethylene glycol; Isocyanate polyethylene glycol NCO-PEO-NCO has a weight average molecular weight of 400 and is provided by Guangdong Wengjiang Chemical Reagent Co., Ltd.; the molar ratio of the diisocyanate polyethylene glycol, 2,2-bis[4-(4-aminophenoxy)phenyl]-1,1,1,3,3,3-hexafluoropropane, 3,3'-diamino-4,4'-difluorodiphenyl sulfone, 1,4-diamino-2,3-dicyanoanthraquinone, catalyst B, and high boiling point solvent is 1:0.5:0.3:0.2:1.2:10; the high boiling point solvent is dimethyl sulfoxide; the catalyst B is dibutyltin dilaurate; and the inert gas is nitrogen.

[0059] The preparation method of the meso-tetramethyl-meso-tetraaminophenyl cup [4] pyrrole is as follows: Guo Yong, Shao Shijun, He Lijun, et al. Synthesis and Characterization of Meso-tetramethyl-meso-tetraaminophenyl cup [4] pyrrole [J]. Chemical Reagents, 2002 (6): 344-345; the initiator is azobisisobutyronitrile; the auxiliary agent is a mixture of a dispersant, a leveling agent and a defoaming agent in a mass ratio of 2:1:3; the dispersant is a polycarboxylate dispersant 5040; the defoaming agent is a defoaming agent Deqian 3100; the leveling agent is an organosilicon leveling agent HY-5030; the catalyst A is dibutyltin dilaurate; the solvent is acetone; the epoxy- and vinyl-containing cage-type silsesquioxane is prepared according to the preparation method of tetraepoxy cage-type silsesquioxane in Example 1 of the authorization announcement number CN101508698B.

[0060] A method for preparing a modified polyurea coating comprises the following steps:

[0061] Step S1, preparation of the component A: uniformly mixing the constituent raw materials of the component A to obtain the component A;

[0062] Step S2, preparation of the component B: uniformly mixing the raw materials of the component B to obtain the component B;

[0063] Step S3, mixing the component A and the component B in a mass ratio of 1:1, stirring evenly, to obtain a modified polyurea coating.

[0064] Comparative Example 1

[0065] A modified polyurea coating and its preparation method are basically the same as those in Example 1, except that meso-tetramethyl-meso-tetra(4-aminophenyl)calix[4]pyrrole and 2,4,6-trivinylcyclotriboroxane are not added.

[0066] Comparative Example 2

[0067] A modified polyurea coating and its preparation method are basically the same as those in Example 1, except that 3,3'-diamino-4,4'-difluorodiphenylsulfone is used instead of 1,4-diamino-2,3-dicyanoanthraquinone; and N-vinyl oxazolidinone is not added.

[0068] In order to further illustrate the beneficial technical effects of the modified polyurea coatings involved in the embodiments of the present invention, the modified polyurea coatings involved in Examples 1-5 and Comparative Examples 1-2 were subjected to relevant performance tests. The test results are shown in Table 1. The curing conditions were curing at 70 °C for 1 h and then drying to constant weight at 100 °C. The test methods are as follows:

[0069] (1) Adhesion grade: Tested with reference to GB / T 9286-1998;

[0070] (2) Tensile strength: Tested with reference to GB / T 23446-2009;

[0071] (3) High temperature resistance: Place the test samples of each example in an aging oven at 150 °C for 2 h, cool to room temperature, and then test the tensile strength according to the method in (2), and calculate the retention rate of the tensile strength. The larger the value, the better the high temperature resistance.

[0072] (4) Weather resistance: Place the test samples of each example in an environment with a temperature of 90 °C and a relative humidity of 90% for 600 h, cool to room temperature, and observe the change of the coating. If the coating has no blistering, softening, no micropores, and no change in viscosity, the weather resistance passes, otherwise it fails.

[0073] Table 1

[0074]

[0075] As can be seen from Table 1, the modified polyurea coatings disclosed in the embodiments of the present invention have more excellent bonding properties, mechanical properties, high temperature resistance and weather resistance than the products of the comparative examples; the combined use of meso-tetramethyl-meso-tetra(4-aminophenyl)calix[4]pyrrole, 2,4,6-trivinylcyclotriboroxane, 1,4-diamino-2,3-dicyanoanthraquinone and N-vinyl oxazolidinone is beneficial to improving the above properties.

[0076] The basic principles, main features and advantages of the present invention have been shown and described above. Those skilled in the art should understand that the present invention is not limited by the above embodiments, and what is described in the above embodiments and the specification is only the principle of the present invention. Without departing from the spirit and scope of the present invention, various changes and improvements will occur to the present invention, and these changes and improvements all fall within the scope of the present invention claimed. The scope of protection required by the present invention is defined by the appended claims and their equivalents.

Claims

1. A modified polyurea coating, characterized in that: The invention comprises a component A and a component B; the mass ratio of the component A to the component B is 1:1; the component A comprises the following raw materials in parts by weight: 60-70 parts of functional polyurea, 3-5 parts of meso-tetramethyl-meso-tetra-p-aminophenyl cup [4] pyrrole, 0.8-1.2 parts of initiator, 0.5-3 parts of auxiliary agent, and catalyst A. 1-2 parts, 30-40 parts of solvent; the component B comprises the following raw materials in parts by weight: 4-6 parts of isocyanoethyl methacrylate, 3-5 parts of cage-type silsesquioxane containing epoxy and vinyl groups, 2-4 parts of 2,4,6-trivinyl cycloboroxane, and 1-3 parts of N-vinyl oxazolidinone; the functional polyurea comprises structural units introduced by the following monomers: diisocyanate polyethylene glycol, 2,2-bis[4-(4-aminophenoxy)phenyl]-1,1,1,3,3,3-hexafluoropropane, 3,3'-diamino-4,4'-difluorodiphenyl sulfone, and 1,4-diamino-2,3-dicyanoanthraquinone; The preparation method of the functional polyurea comprises the following steps: adding diisocyanate polyethylene glycol, 2,2-bis[4-(4-aminophenoxy)phenyl]-1,1,1,3,3,3-hexafluoropropane, 3,3'-diamino-4,4'-difluorodiphenyl sulfone, 1,4-diamino-2,3-dicyanoanthraquinone and catalyst B into a high boiling point solvent, stirring and reacting at 75-90° C. for 2-4 hours in an inert gas atmosphere, then heating to 93-98° C. and continuing stirring and reacting for 8-15 hours, and then evaporating in water. The precipitated polymer is washed with ethanol for 3-6 times, and then the residual solvent is removed by rotary evaporation to obtain a functional polyurea; the molar ratio of the diisocyanate polyethylene glycol, 2,2-bis[4-(4-aminophenoxy)phenyl]-1,1,1,3,3,3-hexafluoropropane, 3,3'-diamino-4,4'-difluorodiphenyl sulfone, 1,4-diamino-2,3-dicyanoanthraquinone, catalyst B, and high boiling point solvent is 1:0.5:0.3:0.2:(0.8-1.2):(6-10).

2. The modified polyurea coating according to claim 1, characterized in that: The diisocyanate polyethylene glycol is diisocyanate polyethylene glycol NCO-PEO-NCO, and has a weight average molecular weight of 400.

3. The modified polyurea coating according to claim 1, characterized in that: The high boiling point solvent is dimethyl sulfoxide; the catalyst B is at least one of dibutyltin dilaurate and stannous octoate; and the inert gas is any one of helium, neon and argon.

4. The modified polyurea coating according to claim 1, characterized in that: The initiator is azobisisobutyronitrile.

5. The modified polyurea coating according to claim 1, characterized in that: The auxiliary agent is prepared by mixing a dispersant, a leveling agent and a defoamer in a mass ratio of (1-2):1:(1-3).

6. The modified polyurea coating according to claim 5, characterized in that: The dispersant is at least one of polycarboxylate dispersant 5040 and sodium hexametaphosphate; the defoamer is one or more of tributyl phosphate, defoamer Deqian 3100 and defoamer BYK088; the leveling agent is at least one of German BYK leveling agent BYK-333 and silicone leveling agent HY-5030.

7. The modified polyurea coating according to claim 1, characterized in that: The catalyst A is at least one of dibutyltin dilaurate and stannous octoate; the solvent is any one of acetone, ethyl acetate, toluene and propylene glycol methyl ether.

8. A method for preparing the modified polyurea coating according to any one of claims 1 to 7, characterized in that: The steps include: Step S1, preparation of the component A: uniformly mixing the constituent raw materials of the component A to obtain the component A; Step S2, preparation of the component B: uniformly mixing the raw materials of the component B to obtain the component B; Step S3, mixing the component A and the component B in a mass ratio of 1:1, stirring evenly, to obtain a modified polyurea coating.

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