High-adhesion weather-resistant chlorinated fluorocarbon-vinyl chloride coating for polyethylene material and preparation method of high-adhesion weather-resistant chlorinated fluorocarbon-vinyl chloride coating

Abstract

The invention discloses a high-adhesion weather-resistant chlorinated fluorocarbon-vinyl chloride coating for a polyethylene material and a preparation method thereof, and relates to the technical field of high polymer materials and coatings. The coating is composed of a component A and a component B, the component A is prepared from an organic solvent, chlorinated fluorocarbon-vinyl chloride polymer resin, an adhesion promoter, a functional aid, polydimethylsiloxane resin and the like; the component B is composed of an isocyanate curing agent; the adhesion promoter is silane coupling agent modified polyamide; the high-adhesion weather-resistant chlorinated fluorocarbon-vinyl chloride coating disclosed by the invention has high adhesion to a polyethylene material, is not easy to fall off from the polyethylene material, can effectively resist ultraviolet irradiation, keeps color and luster for a long time, has superstrong adhesion and good toughness, and ensures that the coating is not damaged after collision; the coating has excellent corrosion resistance, wear resistance, weather resistance and the like, so that the obtained coating can be sprayed on polyethylene substrates in various shapes.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of high polymer materials and coating technology, in particular to a high-adhesion weather-resistant chlorinated fluorocarbon-vinyl chloride coating for polyethylene materials and a preparation method thereof. BACKGROUND

[0002] Polyethylene materials are widely used in the fields of construction and engineering, industry and transportation, and medical treatment due to their outstanding chemical corrosion resistance, light weight, high strength, excellent electrical insulation, and good processing performance, such as water supply pipes, gas pipes, waterproof rolls, irrigation pipes, automobile fuel tanks, mechanical lining plates, ship parts, high-performance protective equipment, artificial joints, and infusion bags. However, when polyethylene is exposed to ultraviolet light, high temperature, and chemical media for a long time, the polyethylene molecular chain will break, leading to material surface powdering and strength reduction, and problems such as aging, embrittlement, and permeation, which affect the service life of polyethylene. Therefore, a layer of coating needs to be sprayed on the surface of polyethylene to protect the polyethylene and prolong its service life.

[0003] However, due to the high crystallinity of polyethylene materials, the crystal structure is closely arranged, and the surface energy is low, making it difficult for the coating to form good wetting and adsorption on the surface of the material, and the coating molecules are not easy to penetrate into the material. In addition, the surface of polyethylene is non-polar, while most coatings are polar. According to the principle of "like dissolves like", the difference in polarity leads to a small affinity between the coating and polyethylene, making it difficult to form a strong chemical bond. Secondly, polyethylene itself is chemically stable and is not easy to react with the components in the coating. This makes it difficult for the coating to form a chemical bond with polyethylene during the curing process, and only relies on physical adsorption force, which is relatively weak. Moreover, the surface of polyethylene is usually smooth with low roughness. The smooth surface reduces the contact area and mechanical interlocking effect between the coating and the material, which is not conducive to the adhesion of the coating. Even if the coating is initially attached to the material surface, it can easily peel off from the smooth surface under external force (such as friction, impact, etc.), which can easily lead to the peeling of the coating.

[0004] Therefore, there is an urgent need for a high-adhesion weather-resistant coating for polyethylene materials to overcome the problem of poor adhesion of ordinary coatings to polyethylene plastics. In addition, it should also be able to effectively resist ultraviolet radiation, maintain color and gloss for a long time, and have strong adhesion and good toughness to ensure that the coating does not break after being knocked. SUMMARY

[0005] To solve the problem of poor adhesion or poor adhesion of general coatings to the smooth surface of polyethylene materials, the purpose of the present application is to provide a high-adhesion weather-resistant chlorinated fluorocarbon-vinyl chloride coating for polyethylene materials and a preparation method thereof.

[0006] To achieve the above objectives, the present invention employs the following technical solution:

[0007] A high-adhesion, weather-resistant chlorofluorocarbon-vinyl chloride coating for polyethylene materials, comprising, by weight, component A and component B; component A comprises the following components: 5-15 parts organic solvent, 30-40 parts chlorofluorocarbon-vinyl chloride polymer resin, 2-5 parts adhesion promoter, 1-3 parts functional additive, 5-25 parts polydimethylsiloxane resin, 0.05-0.1 parts nano-silica, and 15-30 parts filler; component B comprises 1-3 parts isocyanate curing agent.

[0008] The adhesion promoter is a silane coupling agent modified polyamide;

[0009] The chlorofluorocarbon-vinyl chloride polymer resin is prepared according to the following steps:

[0010] ① In a high-pressure reactor, evacuate the atmosphere and purge with argon gas to maintain an anhydrous and oxygen-free environment. When the argon pressure is 0.6–1.5 MPa, add vinyl acetate, acrylic acid, vinyl chloride, initiator AIBN, and a mixed solvent of xylene-butyl acetate to the reactor. Then, introduce trifluorochloroethylene gas into the reactor, heat to 60–70°C, and stir for 8–12 hours. Allow to cool naturally, reduce the pressure, and remove unreacted trifluorochloroethylene gas. Add ethanol to the reactor, stir to mix, and filter. Extract and dry the filtrate to obtain a fluorocarbon-vinyl chloride polymer resin. The extraction temperature is 75–80°C.

[0011] The mass ratio of vinyl acetate, acrylic acid, vinyl chloride, initiator AIBN, xylene-butyl acetate mixed solvent and trifluorochloroethylene gas is 80-100:100:28-32:4-5:140-150:180-220;

[0012] ② Add dispersant, emulsifier, initiator and the fluorocarbon-vinyl chloride polymer resin obtained in step ① to hydrochloric acid aqueous solution, stir and disperse evenly to obtain a reaction solution, heat to 80-90℃, introduce chlorine gas into the reaction solution, control the temperature not to exceed 90℃, control the pressure at 0.3-0.4MPa, terminate the reaction after 30-40 minutes, add n-butyl acetate and stir evenly to obtain chlorofluorocarbon-vinyl chloride polymer resin;

[0013] The mass ratio of hydrochloric acid aqueous solution, dispersant, emulsifier, fluorocarbon-vinyl chloride polymer resin obtained in step ①, initiator and n-butyl acetate is 280-320: 0.2-0.4: 0.1-0.2: 100: 0.1-0.3: 90-110;

[0014] The initiator is tert-butyl hydroperoxide or di-tert-butyl peroxide;

[0015] The dispersant is hydrophobic silica or hydrophobic calcium carbonate powder;

[0016] The emulsifier is a copolymer of ethylene oxide and propylene oxide or a fatty alcohol polyoxyethylene ether.

[0017] Preferably, the silane coupling agent modified polyamide is prepared according to the following steps:

[0018] Add polyamide resin, methanol, and xylene to a reaction vessel, start stirring until the polyamide resin is completely dissolved, then heat to 50-60°C, and add silane coupling agent KH-560 in several portions while stirring. After the addition is complete, heat to 70-80°C and react for 4-5 hours to obtain silane coupling agent modified polyamide.

[0019] The mass ratio of polyamide resin, methanol, xylene, and silane coupling agent KH-560 is 4:3~5:6~10:2~4.

[0020] More preferably, the silane coupling agent KH-560 is added dropwise, and the addition time should be controlled within 1 hour.

[0021] Preferably, the organic solvent is one or two of butyl acetate, ethyl acetate, dichloromethane, and xylene.

[0022] Preferably, the functional additive is one or more of wetting and dispersing agents, defoamers, and leveling agents.

[0023] Preferably, the filler is a mixture of two or more of the following: heavy calcium carbonate, talc, precipitated barium sulfate, sericite powder, and carbon black.

[0024] Preferably, the isocyanate curing agent is an aliphatic isocyanate or / and an aromatic isocyanate.

[0025] Preferably, the wetting and dispersing agent is AFCONA-4010 or / and AFCONA-5051; the defoamer is AFCONA-2020; and the leveling agent is AFCONA-2050.

[0026] Preferably, the mass concentration of the hydrochloric acid aqueous solution is 18-22%.

[0027] Preferably, the xylene-butyl acetate mixed solvent is obtained by mixing xylene and butyl acetate in a mass ratio of 1:1 to 3.

[0028] This invention also includes a method for preparing a high-adhesion, weather-resistant chlorinated fluorocarbon-vinyl chloride coating for polyethylene materials, comprising the following steps:

[0029] (1) Mix 5-15 parts of organic solvent, 15-30 parts of filler and 1-3 parts of functional additive evenly and grind to below 40μm. After filtration, add 30-40 parts of chlorofluorocarbon-vinyl chloride polymer resin, 2-5 parts of adhesion promoter, 5-25 parts of polydimethylsiloxane resin and 0.05-0.1 parts of nano silica to obtain component A;

[0030] (2) Prepare 1 to 3 parts of isocyanate curing agent as component B;

[0031] (3) When using, mix component A and component B evenly to obtain a high adhesion weather-resistant chlorinated fluorocarbon-vinyl chloride coating for polyethylene materials.

[0032] The present invention has the following advantages over the prior art:

[0033] The high-adhesion, weather-resistant chlorofluorocarbon-vinyl chloride coating for polyethylene materials of the present invention has high adhesion to polyethylene materials, the coating is not easy to peel off on polyethylene materials, and can effectively resist ultraviolet radiation, maintain color and gloss for a long time. The super strong adhesion combined with good toughness ensures that the coating will not be damaged after being bumped.

[0034] This invention involves polymerizing trifluorochloroethylene, vinyl acetate, acrylic acid, and vinyl chloride monomers to form a fluorocarbon-vinyl chloride block polymer, followed by chlorination with chlorine gas to obtain a chlorofluorocarbon-vinyl chloride block polymer, which serves as the coating resin matrix. A polyamide adhesion promoter modified with a silane coupling agent is added, along with polydimethylsiloxane. By adding fillers and other additives, a high-adhesion, weather-resistant coating for sprayable polyethylene materials is formed.

[0035] First, the fluorine element introduced into the chlorofluorocarbon-vinyl chloride polymer resin of this invention has high electronegativity and strong carbon-fluorine bond energy, resulting in exceptionally superior properties, good weather resistance, and unique non-stick and low-friction characteristics. Second, the introduction of silane coupling agent-modified polyamide adhesion promoter and polydimethylsiloxane resin, along with the surface energy of silicon itself, gives the coating excellent corrosion resistance, wear resistance, and weather resistance. Therefore, the resulting coating can be sprayed onto polyethylene substrates of various shapes. Detailed Implementation

[0036] The purpose of this invention is to provide a high-adhesion, weather-resistant chlorinated fluorocarbon-vinyl chloride coating for polyethylene materials and its preparation method.

[0037] The synthesis equation for the fluorocarbon-vinyl chloride polymer resin of this invention is as follows:

[0038]

[0039] The synthesis equation for chlorofluorocarbon-vinyl chloride polymer resin is as follows:

[0040] The synthesis equation for the silane coupling agent modified polyamide adhesion promoter is as follows:

[0041]

[0042] All monomers of this invention, such as vinyl acetate, acrylic acid and vinyl chloride monomers, need to be purified by vacuum distillation to remove polymerization inhibitors.

[0043] Hydrophobic silica is Evonik's E 972, hydrophobic calcium carbonate powder, is provided by Shanghai Yuanjiang Chemical Co., Ltd., model number 303.

[0044] In the embodiments of this invention, vinyl acetate was provided by Tianjin Damao Chemical Reagent Factory, acrylic acid was provided by Jiangyin Zhenfa Chemical Co., Ltd., vinyl chloride monomer was provided by Xinpu Chemical (Taixing) Co., Ltd., trifluorochloroethylene was provided by Dalian Date Gas Co., Ltd., polyamide resin was provided by Shandong Jiaying Chemical Technology Co., Ltd., and polydimethylsiloxane resin was provided by Zhongshan Dixing Chemical Co., Ltd.

[0045] The ethylene oxide-propylene oxide copolymer was provided by Angxing New Carbon Materials Changzhou Co., Ltd.

[0046] The fatty alcohol polyoxyethylene ether is supplied by BASF AG.

[0047] The aliphatic isocyanate curing agent used in this invention is Desmodur N75, and the aromatic isocyanate curing agent is Desmodur L75.

[0048] The present invention will be further described below with reference to specific embodiments.

[0049] Example 1

[0050] A high-adhesion, weather-resistant chlorofluorocarbon-vinyl chloride coating for polyethylene materials is composed of component A and component B. Component A consists of the following components: 5 kg of butyl acetate, 30 kg of chlorofluorocarbon-vinyl chloride polymer resin, 2 kg of adhesion promoter, 1 kg of wetting and dispersing agent AFCONA-4010, 5 kg of polydimethylsiloxane resin, 0.05 kg of nano-silica, 10 kg of heavy calcium carbonate, and 5 kg of talc. Component B consists of 1 kg of aliphatic isocyanate.

[0051] The adhesion promoter is a silane coupling agent modified polyamide;

[0052] The silane coupling agent modified polyamide was prepared according to the following steps:

[0053] Add 2 kg of polyamide resin, 1.5 kg of methanol, and 3 kg of xylene to a reaction vessel. Start stirring until the polyamide resin is completely dissolved. Then, heat the mixture to 50°C and add 1 kg of silane coupling agent KH-560 in 5 portions while stirring. After the addition is complete, heat the mixture to 70°C and react for 5 hours to obtain silane coupling agent modified polyamide.

[0054] The chlorofluorocarbon-vinyl chloride polymer resin is prepared according to the following steps:

[0055] ① Evacuate the high-pressure reactor and purge with argon gas to maintain an anhydrous and oxygen-free environment. When the argon gas pressure is 0.6 MPa, add 20 kg of vinyl acetate, 25 kg of acrylic acid, 7 kg of vinyl chloride, 1 kg of initiator AIBN, and 35 kg of xylene-butyl acetate mixed solvent to the high-pressure reactor. Then, purge 45 kg of trifluorochloroethylene gas into the high-pressure reactor, heat to 60°C and stir for 8 hours. Allow to cool naturally, reduce the pressure and remove unreacted trifluorochloroethylene gas. Add ethanol to the reactor, stir and mix well, then filter. Extract the filtrate (extraction temperature is 75-80°C), dry and obtain fluorocarbon-vinyl chloride polymer resin.

[0056] ② Add 0.1 kg of dispersant, 0.05 kg of emulsifier, 0.05 kg of initiator and 50 kg of the fluorocarbon-vinyl chloride polymer resin obtained in step ① to 140 kg of hydrochloric acid aqueous solution with a mass concentration of 18%. Stir and disperse evenly to obtain a reaction solution. Heat to 80℃, introduce chlorine gas into the reaction solution, control the temperature not to exceed 90℃, control the pressure at 0.3 MPa, terminate the reaction after 30 minutes, add 45 kg of n-butyl acetate and stir evenly to obtain chlorofluorocarbon-vinyl chloride polymer resin.

[0057] The initiator is tert-butyl hydroperoxide;

[0058] The dispersant is hydrophobic silica;

[0059] The emulsifier is a copolymer of ethylene oxide and propylene oxide.

[0060] Example 2

[0061] A high-adhesion, weather-resistant chlorofluorocarbon-vinyl chloride coating for polyethylene materials is composed of component A and component B. Component A consists of the following components: 15 kg of dichloromethane, 40 kg of chlorofluorocarbon-vinyl chloride polymer resin, 5 kg of adhesion promoter, 3 kg of defoamer AFCONA-2020, 25 kg of polydimethylsiloxane resin, 0.1 kg of nano-silica, 15 kg of precipitated barium sulfate, and 15 kg of sericite powder. Component B consists of 2 kg of aliphatic isocyanate and 1 kg of aromatic isocyanate.

[0062] The adhesion promoter is a silane coupling agent modified polyamide;

[0063] The silane coupling agent modified polyamide was prepared according to the following steps:

[0064] Add 2 kg of polyamide resin, 2.5 kg of methanol, and 5 kg of xylene to a reaction vessel. Start stirring until the polyamide resin is completely dissolved. Then, raise the temperature to 60°C and add 2 kg of silane coupling agent KH-560 in 5 portions while stirring. After the addition is complete, raise the temperature to 80°C and react for 4 hours to obtain silane coupling agent modified polyamide.

[0065] The chlorofluorocarbon-vinyl chloride polymer resin is prepared according to the following steps:

[0066] ① Evacuate the high-pressure reactor and purge with argon gas to maintain an anhydrous and oxygen-free environment. When the argon gas pressure is 1.5 MPa, add 25 kg of vinyl acetate, 25 kg of acrylic acid, 8 kg of vinyl chloride, 1.25 kg of initiator AIBN, and 37.5 kg of xylene-butyl acetate mixed solvent to the high-pressure reactor. Then, purge 55 kg of trifluorochloroethylene gas into the high-pressure reactor, heat to 70°C and stir for 12 hours. Allow to cool naturally, reduce the pressure and remove unreacted trifluorochloroethylene gas. Add ethanol to the reactor, stir and mix well, then filter. Extract the filtrate (extraction temperature is 75-80°C), dry it, and obtain fluorocarbon-vinyl chloride polymer resin.

[0067] ② Add dispersant, emulsifier, initiator and the fluorocarbon-vinyl chloride polymer resin obtained in step ① to a 22% hydrochloric acid aqueous solution and stir to disperse evenly to obtain a reaction solution. Heat to 90℃, introduce chlorine gas into the reaction solution, control the temperature not to exceed 90℃, control the pressure at 0.4MPa, terminate the reaction after 40 minutes, add n-butyl acetate and stir evenly to obtain chlorofluorocarbon-vinyl chloride polymer resin;

[0068] The initiator is di-tert-butyl peroxide;

[0069] The dispersant is hydrophobic calcium carbonate powder;

[0070] The emulsifier is fatty alcohol polyoxyethylene ether.

[0071] Example 3

[0072] A high-adhesion, weather-resistant chlorofluorocarbon-vinyl chloride coating for polyethylene materials is composed of component A and component B. Component A consists of the following components: 3 kg butyl acetate, 3 kg ethyl acetate, 32 kg chlorofluorocarbon-vinyl chloride polymer resin, 3 kg adhesion promoter, 0.8 kg wetting and dispersing agent AFCONA-5051, 0.4 kg leveling agent AFCONA-2050, 8 kg polydimethylsiloxane resin, 0.06 kg nano-silica, 9 kg sericite powder, and 9 kg carbon black. Component B consists of 1.0 kg aliphatic isocyanate curing agent and 0.5 kg aromatic isocyanate curing agent.

[0073] The adhesion promoter is a silane coupling agent modified polyamide;

[0074] Add 2 kg of polyamide resin, 2 kg of methanol, and 4 kg of xylene to a reaction vessel. Start stirring until the polyamide resin is completely dissolved. Then, raise the temperature to 52°C and add 1.5 kg of silane coupling agent KH-560 in 5 portions while stirring. After the addition is complete, raise the temperature to 72°C and react for 4.5 hours to obtain silane coupling agent modified polyamide.

[0075] The chlorofluorocarbon-vinyl chloride polymer resin is prepared according to the following steps:

[0076] ① Evacuate the high-pressure reactor and purge with argon gas to maintain an anhydrous and oxygen-free environment. When the argon gas pressure is 1.5 MPa, add 24 kg of vinyl acetate, 25 kg of acrylic acid, 7.5 kg of vinyl chloride, 1.1 kg of initiator AIBN, and 36 kg of xylene-butyl acetate mixed solvent to the high-pressure reactor. Then, purge 47.5 kg of trifluorochloroethylene gas into the high-pressure reactor, heat to 70°C and stir for 12 hours. Allow to cool naturally, reduce the pressure and release the unreacted trifluorochloroethylene gas. Add ethanol to the reactor, stir and mix well, then filter. Extract the filtrate (extraction temperature is 75-80°C), dry it, and obtain the fluorocarbon-vinyl chloride polymer resin.

[0077] ② Add 0.16 kg of dispersant, 0.07 kg of emulsifier, 0.12 kg of initiator and 50 kg of the fluorocarbon-vinyl chloride polymer resin obtained in step ① to 156 kg of hydrochloric acid aqueous solution with a mass concentration of 20%. Stir and disperse evenly to obtain a reaction solution. Heat to 90℃, introduce chlorine gas into the reaction solution, control the temperature not to exceed 90℃, control the pressure at 0.4 MPa, terminate the reaction after 40 minutes, add 52 kg of n-butyl acetate and stir evenly to obtain chlorofluorocarbon-vinyl chloride polymer resin.

[0078] The initiator is tert-butyl hydroperoxide;

[0079] The dispersant is hydrophobic calcium carbonate powder;

[0080] The emulsifier is a copolymer of ethylene oxide and propylene oxide.

[0081] Example 4

[0082] A high-adhesion, weather-resistant chlorofluorocarbon-vinyl chloride coating for polyethylene materials is composed of component A and component B. Component A consists of the following components: 8 kg ethyl acetate, 4 kg dichloromethane, 38 kg chlorofluorocarbon-vinyl chloride polymer resin, 4 kg adhesion promoter, 1 kg defoamer AFCONA-2020, 0.5 kg leveling agent AFCONA-2050, 22 kg polydimethylsiloxane resin, 0.08 kg nano-silica, 10 kg talc, 10 kg precipitated barium sulfate, and 5 kg sericite powder. Component B consists of 2.5 kg aromatic isocyanate.

[0083] The adhesion promoter is a silane coupling agent modified polyamide;

[0084] Add 2 kg of polyamide resin, 1.75 kg of methanol, and 3.5 kg of xylene to a reaction vessel. Start stirring until the polyamide resin is completely dissolved. Then, raise the temperature to 58°C and add 1.75 kg of silane coupling agent KH-560 in 6 portions while stirring. After the addition is complete, raise the temperature to 74°C and react for 4.5 hours to obtain silane coupling agent modified polyamide.

[0085] The chlorofluorocarbon-vinyl chloride polymer resin is prepared according to the following steps:

[0086] ① Evacuate the high-pressure reactor and purge with argon gas to maintain an anhydrous and oxygen-free environment. When the argon gas pressure is 1.2 MPa, add 23 kg of vinyl acetate, 25 kg of acrylic acid, 7.5 kg of vinyl chloride, 1.2 kg of initiator AIBN, and 37 kg of xylene-butyl acetate mixed solvent to the high-pressure reactor. Then, purge 52.5 kg of trifluorochloroethylene gas into the high-pressure reactor, heat to 68°C and stir for 10 hours. Allow to cool naturally, reduce the pressure and remove unreacted trifluorochloroethylene gas. Add ethanol to the reactor, stir and mix well, then filter. Extract the filtrate (extraction temperature is 75-80°C), dry it, and obtain fluorocarbon-vinyl chloride polymer resin.

[0087] ② Add 0.15 kg of dispersant, 0.09 kg of emulsifier, 0.125 kg of initiator, and 50 kg of the fluorocarbon-vinyl chloride polymer resin obtained in step ① to 155 kg of hydrochloric acid aqueous solution with a mass concentration of 20%. Stir and disperse the mixture to obtain a reaction solution. Heat the solution to 88°C and introduce chlorine gas into it. Control the temperature to not exceed 90°C and the pressure to 0.35 MPa. Terminate the reaction after 38 minutes. Add 52.5 kg of n-butyl acetate and stir until homogeneous to obtain chlorofluorocarbon-vinyl chloride polymer resin.

[0088] The initiator is di-tert-butyl peroxide;

[0089] The dispersant is hydrophobic calcium carbonate powder;

[0090] The emulsifier is fatty alcohol polyoxyethylene ether.

[0091] Example 5

[0092] A high-adhesion, weather-resistant chlorofluorocarbon-vinyl chloride coating for polyethylene materials is composed of component A and component B. Component A consists of the following components: 5 kg of dichloromethane, 5 kg of xylene, 35 kg of chlorofluorocarbon-vinyl chloride polymer resin, 3 kg of adhesion promoter, 10.6 kg of wetting and dispersing agent AFCONA-505, 1.5 kg of defoamer AFCONA-2020, 15 kg of polydimethylsiloxane resin, 0.08 kg of nano-silica, 5 kg of heavy calcium carbonate, 10 kg of precipitated barium sulfate, and 5 kg of carbon black. Component B consists of 2 kg of aliphatic isocyanate.

[0093] The adhesion promoter is a silane coupling agent modified polyamide;

[0094] Add 1 kg of polyamide resin, 1 kg of methanol, and 2 kg of xylene to a reaction vessel. Start stirring until the polyamide resin is completely dissolved. Then, heat the mixture to 55°C and add 1 kg of silane coupling agent KH-560 in 6 portions while stirring. After the addition is complete, heat the mixture to 75°C and react for 4.5 hours to obtain silane coupling agent modified polyamide.

[0095] The chlorofluorocarbon-vinyl chloride polymer resin is prepared according to the following steps:

[0096] ① Evacuate the high-pressure reactor and purge it with argon gas to maintain an anhydrous and oxygen-free environment. When the argon gas pressure is 1.0 MPa, add 22.5 kg of vinyl acetate, 25 kg of acrylic acid, 7.5 kg of vinyl chloride, 1.1 kg of initiator AIBN, and 36 kg of xylene-butyl acetate mixed solvent to the high-pressure reactor. Then, purge 50 kg of trifluorochloroethylene gas into the high-pressure reactor, heat it to 65°C and stir for 10 hours. Allow it to cool naturally, reduce the pressure and remove the unreacted trifluorochloroethylene gas. Add ethanol to the reactor, stir and mix well, and then filter. Extract and dry the filtrate to obtain fluorocarbon-vinyl chloride polymer resin.

[0097] ② Add 0.15 kg of dispersant, 0.08 kg of emulsifier, 0.1 kg of initiator and 50 kg of the fluorocarbon-vinyl chloride polymer resin obtained in step ① to 150 kg of hydrochloric acid aqueous solution with a mass concentration of 20%. Stir and disperse evenly to obtain a reaction solution. Heat to 85℃, introduce chlorine gas into the reaction solution, control the temperature not to exceed 90℃, control the pressure at 0.35 MPa, terminate the reaction after 35 minutes, add 50 kg of n-butyl acetate and stir evenly to obtain chlorofluorocarbon-vinyl chloride polymer resin.

[0098] The initiator is di-tert-butyl peroxide;

[0099] The dispersant is hydrophobic silica;

[0100] The emulsifier is fatty alcohol polyoxyethylene ether.

[0101] Example 6

[0102] Example 1 describes a method for preparing a high-adhesion, weather-resistant chlorinated fluorocarbon-vinyl chloride coating for polyethylene materials, comprising the following steps:

[0103] (1) Mix 5 kg of butyl acetate, 1 kg of wetting and dispersing agent AFCONA-4010, 10 kg of heavy calcium carbonate and 5 kg of talc powder evenly and grind to below 40 μm. After filtration, add 30 kg of chlorofluorocarbon-vinyl chloride polymer resin, 2 kg of adhesion promoter, 5 kg of polydimethylsiloxane resin and 0.05 kg of nano silica to obtain component A.

[0104] (2) Prepare 1 kg of aliphatic isocyanate as component B;

[0105] (3) When using, mix component A and component B evenly to obtain a high adhesion weather-resistant chlorinated fluorocarbon-vinyl chloride coating for polyethylene materials.

[0106] Example 7

[0107] Example 2 describes a method for preparing a high-adhesion, weather-resistant chlorinated fluorocarbon-vinyl chloride coating for polyethylene materials, comprising the following steps:

[0108] (1) Mix 15 kg of dichloromethane, 3 kg of defoamer AFCONA-2020, 15 kg of precipitated barium sulfate and 15 kg of sericite powder evenly and grind to below 40 μm. After filtration, add 40 kg of chlorofluorocarbon-vinyl chloride polymer resin, 5 kg of adhesion promoter, 25 kg of polydimethylsiloxane resin and 0.1 kg of nano silica to obtain component A.

[0109] (2) Prepare 2 kg of aliphatic isocyanate and 1 kg of aromatic isocyanate as component B;

[0110] (3) When using, mix component A and component B evenly to obtain a high adhesion weather-resistant chlorinated fluorocarbon-vinyl chloride coating for polyethylene materials.

[0111] Example 8

[0112] Example 3 describes a method for preparing a high-adhesion, weather-resistant chlorinated fluorocarbon-vinyl chloride coating for polyethylene materials, comprising the following steps:

[0113] (1) Mix 3 kg of butyl acetate, 3 kg of ethyl acetate, 0.8 kg of wetting and dispersing agent AFCONA-5051, 0.4 kg of leveling agent AFCONA-2050, 9 kg of sericite powder and 9 kg of carbon black evenly and grind to below 40 μm. After filtration, add 32 kg of chlorofluorocarbon-vinyl chloride polymer resin, 3 kg of adhesion promoter, 8 kg of polydimethylsiloxane resin and 0.06 kg of nano silica to obtain component A;

[0114] (2) Prepare 1.0 kg of aliphatic isocyanate curing agent and 0.5 kg of aromatic isocyanate curing agent as component B;

[0115] (3) When using, mix component A and component B evenly to obtain a high adhesion weather-resistant chlorinated fluorocarbon-vinyl chloride coating for polyethylene materials.

[0116] Example 9

[0117] Example 4 describes a method for preparing a high-adhesion, weather-resistant chlorinated fluorocarbon-vinyl chloride coating for polyethylene materials, comprising the following steps:

[0118] (1) Mix 8 kg of ethyl acetate, 4 kg of dichloromethane, 1 kg of defoamer AFCONA-2020, 0.5 kg of leveling agent AFCONA-2050, 10 kg of talc, 10 kg of precipitated barium sulfate and 5 kg of sericite powder evenly and grind to below 40 μm. After filtration, add 38 kg of chlorofluorocarbon-vinyl chloride polymer resin, 4 kg of adhesion promoter, 22 kg of polydimethylsiloxane resin and 0.08 kg of nano silica to obtain component A;

[0119] (2) Prepare 2.5 kg of aromatic isocyanate as component B;

[0120] (3) When using, mix component A and component B evenly to obtain a high adhesion weather-resistant chlorinated fluorocarbon-vinyl chloride coating for polyethylene materials.

[0121] Example 10

[0122] Example 5 describes a method for preparing a high-adhesion, weather-resistant chlorinated fluorocarbon-vinyl chloride coating for polyethylene materials, comprising the following steps:

[0123] (1) Mix 5 kg of dichloromethane, 5 kg of xylene, 0.6 kg of wetting and dispersing agent AFCONA-5051, 1.5 kg of defoamer AFCONA-2020, 5 kg of heavy calcium carbonate, 10 kg of precipitated barium sulfate and 5 kg of carbon black evenly and grind to below 40 μm. After filtration, add 35 kg of chlorofluorocarbon-vinyl chloride polymer resin, 3 kg of adhesion promoter, 15 kg of polydimethylsiloxane resin and 0.08 kg of nano silica to obtain component A;

[0124] (2) Prepare 2 kg of aliphatic isocyanate as component B;

[0125] (3) When using, mix component A and component B evenly to obtain a high adhesion weather-resistant chlorinated fluorocarbon-vinyl chloride coating for polyethylene materials.

[0126] After the polyethylene material of the present invention is sprayed with a high-adhesion, weather-resistant chlorofluorocarbon-vinyl chloride coating, it can be cured at room temperature for about 7 days, or placed in an oven and cured at 115-125°C for 2-3 hours.

[0127] The performance of the high-adhesion, weather-resistant chlorofluorocarbon-vinyl chloride coatings used for the polyethylene materials obtained in Examples 6-10 was tested. The adhesion of the coating on the polyethylene material was tested according to GB / T 9286-2012, the surface contact angle was tested by image analysis (static contact angle), and the gloss loss rate after 1200 hours of fluorescent UV aging was tested according to GB / T 23987-2009. The results are shown in Table 1.

[0128] Table 1 Performance Test Data

[0129] adhesion (grade) surface contact angle (°) light loss rate (%) Example 6 0 grade 105 4 Example 7 0 grade 106 4 Example 8 0 grade 107 3 Example 9 0 grade 107 3 Example 10 0 grade 108 3

[0130] As can be seen from the results in Table 1, the high adhesion and weather-resistant chlorofluorocarbon-vinyl chloride coating of the present invention can achieve an adhesion level of 0 on polyethylene materials, indicating excellent adhesion to polyethylene materials. Combined with good toughness, this ensures that the coating will not be damaged after impact. The surface contact angle is as high as 105°, indicating good hydrophobicity and strong anti-fouling ability. The gloss loss rate is ≤4%, indicating that the coating of the present invention has stable gloss and good weather resistance.

Claims

1. A high-adhesion, weather-resistant chlorinated fluorocarbon-vinyl chloride coating for polyethylene materials, characterized in that: The product, by weight, comprises component A and component B; component A consists of the following components: 5-15 parts organic solvent, 30-40 parts chlorofluorocarbon-vinyl chloride polymer resin, 2-5 parts adhesion promoter, 1-3 parts functional additive, 5-25 parts polydimethylsiloxane resin, 0.05-0.1 parts nano silica, and 15-30 parts filler; component B consists of 1-3 parts isocyanate curing agent. The adhesion promoter is a silane coupling agent modified polyamide; The chlorofluorocarbon-vinyl chloride polymer resin is prepared according to the following steps: ① In a high-pressure reactor, evacuate the atmosphere and purge with argon gas to maintain an anhydrous and oxygen-free environment. When the argon pressure is 0.6–1.5 MPa, add vinyl acetate, acrylic acid, vinyl chloride, initiator AIBN, and a mixed solvent of xylene-butyl acetate to the reactor. Then, introduce trifluorochloroethylene gas into the reactor, heat to 60–70°C, and stir for 8–12 hours. Allow to cool naturally, reduce the pressure, and remove unreacted trifluorochloroethylene gas. Add ethanol to the reactor, stir to mix, and filter. Extract and dry the filtrate to obtain a fluorocarbon-vinyl chloride polymer resin. The extraction temperature is 75–80°C. The mass ratio of vinyl acetate, acrylic acid, vinyl chloride, initiator AIBN, xylene-butyl acetate mixed solvent and trifluorochloroethylene gas is 80-100:100:28-32:4-5:140-150:180-220; ② Add dispersant, emulsifier, initiator and the fluorocarbon-vinyl chloride polymer resin obtained in step ① to hydrochloric acid aqueous solution, stir and disperse evenly to obtain a reaction solution, heat to 80-90℃, introduce chlorine gas into the reaction solution, control the temperature not to exceed 90℃, control the pressure at 0.3-0.4MPa, terminate the reaction after 30-40 minutes, add n-butyl acetate and stir evenly to obtain chlorofluorocarbon-vinyl chloride polymer resin; The mass ratio of hydrochloric acid aqueous solution, dispersant, emulsifier, fluorocarbon-vinyl chloride polymer resin obtained in step ①, initiator and n-butyl acetate is 280-320: 0.2-0.4: 0.1-0.2: 100: 0.1-0.3: 90-110; The initiator is tert-butyl hydroperoxide or di-tert-butyl peroxide; The dispersant is hydrophobic silica or hydrophobic calcium carbonate powder; The emulsifier is a copolymer of ethylene oxide and propylene oxide or a fatty alcohol polyoxyethylene ether.

2. The high-adhesion, weather-resistant chlorinated fluorocarbon-vinyl chloride coating for polyethylene materials according to claim 1, characterized in that: The silane coupling agent modified polyamide was prepared according to the following steps: Add polyamide resin, methanol, and xylene to a reaction vessel, start stirring until the polyamide resin is completely dissolved, then heat to 50-60°C, and add silane coupling agent KH-560 in several portions while stirring. After the addition is complete, heat to 70-80°C and react for 4-5 hours to obtain silane coupling agent modified polyamide. The mass ratio of polyamide resin, methanol, xylene, and silane coupling agent KH-560 is 4:3~5:6~10:2~4.

3. The high-adhesion, weather-resistant chlorinated fluorocarbon-vinyl chloride coating for polyethylene materials according to claim 1, characterized in that: The organic solvent is one or two of butyl acetate, ethyl acetate, dichloromethane, and xylene.

4. The high-adhesion, weather-resistant chlorinated fluorocarbon-vinyl chloride coating for polyethylene materials according to claim 1, characterized in that: The functional additive is one or more of wetting and dispersing agents, defoamers, and leveling agents.

5. The high-adhesion, weather-resistant chlorinated fluorocarbon-vinyl chloride coating for polyethylene materials according to claim 1, characterized in that: The filler is a mixture of two or more of the following: heavy calcium carbonate, talc, precipitated barium sulfate, sericite powder, and carbon black.

6. The high-adhesion, weather-resistant chlorinated fluorocarbon-vinyl chloride coating for polyethylene materials according to claim 1, characterized in that: The isocyanate curing agent is an aliphatic isocyanate or / and an aromatic isocyanate.

7. The high-adhesion, weather-resistant chlorinated fluorocarbon-vinyl chloride coating for polyethylene materials according to claim 1, characterized in that: The wetting and dispersing agent is AFCONA-4010 or / and AFCONA-5051; the defoamer is AFCONA-2020; and the leveling agent is AFCONA-2050.

8. The high-adhesion, weather-resistant chlorinated fluorocarbon-vinyl chloride coating for polyethylene materials according to claim 1, characterized in that: The hydrochloric acid aqueous solution has a mass concentration of 18-22%.

9. The high-adhesion, weather-resistant chlorinated fluorocarbon-vinyl chloride coating for polyethylene materials according to claim 1, characterized in that: The xylene-butyl acetate mixed solvent is obtained by mixing xylene and butyl acetate in a mass ratio of 1:1 to 3.

10. The method for preparing a high-adhesion, weather-resistant chlorinated fluorocarbon-vinyl chloride coating for polyethylene materials according to claim 1, characterized in that: Includes the following steps: (1) Mix 5-15 parts of organic solvent, 15-30 parts of filler and 1-3 parts of functional additive evenly and grind to below 40μm. After filtration, add 30-40 parts of chlorofluorocarbon-vinyl chloride polymer resin, 2-5 parts of adhesion promoter, 5-25 parts of polydimethylsiloxane resin and 0.05-0.1 parts of nano silica to obtain component A; (2) Prepare 1 to 3 parts of isocyanate curing agent as component B; (3) When using, mix component A and component B evenly to obtain a high adhesion weather-resistant chlorinated fluorocarbon-vinyl chloride coating for polyethylene materials.

Images