A coating agent and its preparation method and application

Abstract

The present invention discloses a coating agent and a preparation method and application thereof. The coating agent is obtained by polymerization of a siloxane hydroxy perfluoropolyether monomer (HOCH2CF2-Rf-O-CF2CH2O-X-Si(OR)3(I)), a fluorine-free monomer, an epoxy group-containing monomer, an organic siloxane monomer, an isocyanate monomer and an auxiliary agent. The siloxane hydroxy perfluoropolyether monomer in the present invention can play the role of a fluorosilicone polymer interpenetrating network structure, and can improve the shortcomings of fluorosilicone materials such as poor adhesion, low hardness and general strength. The electronic protective coating agent prepared therefrom has better moisture resistance, water and oil repellency, salt spray resistance and acid and alkali resistance.

Description

Technical Field

[0001] The invention belongs to the field of chemical technology, and specifically relates to a polymer, a coating agent and a preparation method thereof, and application of the coating agent as a protective coating agent for electronic products. Background Art

[0002] Intelligent electronic and electrical equipment contains printed circuit boards with high-density semiconductor chips. They can be corroded by acids or salts produced in rain, moisture, fog, sweat and other environments, causing circuit short circuits and damage. Non-fluorine-based waterproof and moisture-proof coatings must be more than 100μm thick to achieve the desired effect; fluorinated acrylate homopolymers are favored for their thin film layers (less than 1μm) coated on the surface of the circuit substrate. However, existing fluorinated waterproof and moisture-proof coatings for electronic products have problems such as insufficient resistance to chemical corrosion (acids and salts) and low waterproof levels, which are prone to erroneous operations and poor contact.

[0003] Existing waterproof and moisture-proof coatings achieve waterproof and moisture-proof effects by coating various resin solutions on the circuit substrate and then drying and curing to form a film of a certain thickness. However, this process is time-consuming and results in low production efficiency. If the coating film is thick, it will also cause bubbles and produce defects such as uneven coating.

[0004] At present, the use of perfluoroalkyl polymers to coat the surface of circuit board substrates can achieve better coating effects, but this type of perfluoroalkyl compound is gradually restricted by countries around the world due to its shortcomings of poor degradation, bioaccumulation and carcinogenicity. Perfluoropolyether and its derivatives are an important alternative because they do not contain perfluoroalkyl components.

[0005] Fluoropolymer electronic coatings have poor moisture resistance and water and oil repellency, small water contact angles, and poor chemical corrosion resistance on circuit substrates. Perfluoroalkyl polymer electronic coatings cause great harm to the environment and human health. Therefore, it is necessary to develop new electronic product protective coatings with reduced toxicity, better moisture resistance, water and oil repellency, and higher contact angles. Summary of the invention

[0006] In order to solve the above technical problems, the present invention provides a polymer, and also provides a coating agent, a preparation method of the coating agent and the application of the coating agent as a protective coating agent for electronic products.

[0007] In a first aspect, the present invention provides a polymer, wherein the polymer is polymerized from the following monomer raw materials:

[0008] Siloxane hydroxy perfluoropolyether monomers and monomers containing epoxy groups.

[0009] The siloxane hydroxyl perfluoropolyether monomer is represented by formula (I):

[0010] HOCH2CF2-Rf-OCF2CH2O-X-Si(OR)3(I),

[0011] Wherein, Rf represents -(C4F8O) a -(C3F6O) b -(C2F4O) c -(CF2O) d -, wherein a, b, c and d are each independently an integer within the range of 0 to 200, and the sum of a, b, c and d is at least 1;

[0012] X is a straight chain or branched C3-C6 aliphatic group;

[0013] R is a linear or branched C1-C6 aliphatic group.

[0014] As a preferred embodiment of the present invention, in Rf in formula (I), a, b, c, d are each independently an integer within the range of 0 to 40, and the sum of a, b, c, d is at least 1; preferably, a, b, c, d are each independently an integer within the range of 0 to 20, and the sum of a, b, c, d is at least 1.

[0015] As a preferred embodiment of the present invention, non-limiting examples of the siloxane hydroxy perfluoropolyether monomer are as follows:

[0016] HOCH2CF2(OCF2) 10 OCF2CH2OCH2CH2CH2Si(OCH3)3;

[0017] HOCH2CF2(OCF2CF2) 10 OCF2CH2OCH2CH2CH2Si(OCH3)3;

[0018] HOCH2CF2(C3F6O) 10 OCF2CH2OCH2CH2CH2Si(OCH3)3;

[0019] HOCH2CF2(OCF2)2(OCF2CF2) 10 OCF2CH2OCH2CH2CH2Si(OCH3)3;

[0020] HOCH2CF2(OCF2)2(OCF2CF2) 10 (C2F4O)4OCF2CH2OCH2CH2CH2Si(OCH3)3;

[0021] HOCH2CF2(OCF2)2(OCF2CF2) 10(C3F6O)4OCF2CH2OCH2CH2CH2Si(OCH3)3;

[0022] HOCH2CF2(OCF2) 10 OCF2CH2OCH2CH2CH2CH2Si(OCH3)3;

[0023] HOCH2CF2(OCF2) 10 OCF2CH2OCH2CH2CH2CH2Si(OCH2CH3)3.

[0024] The epoxy group-containing monomer refers to a monomer containing an epoxy group and capable of being polymerized with acrylate; preferably, the epoxy group-containing monomer is selected from one or both of glycidyl methacrylate and allyl glycidyl ether.

[0025] The mass ratio of the silicone hydroxy perfluoropolyether monomer to the epoxy group-containing monomer is (10-40):(0.5-8); preferably, the mass ratio of the silicone hydroxy perfluoropolyether monomer to the epoxy group-containing monomer is (15-35):(1-4).

[0026] As a preferred embodiment of the present invention, the monomer raw material of the polymer further includes one or more of a fluorine-free monomer, an organic siloxane monomer and an isocyanate monomer.

[0027] Preferably, in the monomer raw material, the mass ratio of the siloxane hydroxy perfluoropolyether monomer, the fluorine-free monomer, the epoxy group-containing monomer, the organic siloxane monomer and the isocyanate monomer is (1-40):(2-20):(0.5-8):(0.5-5):(0.5-5).

[0028] More preferably, in the monomer raw material, the mass ratio of the siloxane hydroxy perfluoropolyether monomer, the fluorine-free monomer, the epoxy group-containing monomer, the organosiloxane monomer and the isocyanate monomer is (15-35):(6-10):(1-4):(0.5-3):(0.5-3).

[0029] The fluorine-free monomer is a compound having one carbon-carbon double bond, and preferred examples of the fluorine-free monomer include one or more of ethylene, vinyl acetate, vinyl halides such as vinyl chloride, vinylidene halides such as vinylidene chloride, acrylonitrile, styrene, methyl (meth)acrylate, n-butyl methacrylate, tert-butyl methacrylate, isobornyl (meth)acrylate, benzyl (meth)acrylate, polyethylene glycol (meth)acrylate, polypropylene glycol (meth)acrylate, methoxypolyethylene glycol (meth)acrylate, methoxypolypropylene glycol (meth)acrylate and vinyl alkyl ether.

[0030] More preferably, the fluorine-free monomer is methyl methacrylate or butyl methacrylate.

[0031] The organosiloxane monomer is an organosiloxane monomer containing an amino group, a mercapto group or a double bond and capable of undergoing polymerization reaction with acrylate. Preferably, the organosiloxane monomer is selected from one or more of vinyl trimethoxy silane, vinyl triethoxy silane, aminopropyl triethoxy silane, mercaptopropyl trimethoxy silane, methacryloxypropyl trimethyl silane, vinyl silicone oil and hydrogen silicone oil.

[0032] More preferably, the organosiloxane monomer is vinyltrimethoxysiloxane.

[0033] The isocyanate monomer is a vinyl-terminated isocyanate capable of undergoing polymerization reaction with acrylate. Preferably, the isocyanate monomer is selected from one or more of isocyanoethyl methacrylate, 2-chloroallyl isothiocyanate, methacryloyl isocyanate and isocyanocyclohexene.

[0034] More preferably, the isocyanate monomer is isocyanoethyl methacrylate or isocyanocyclohexene.

[0035] As a preferred embodiment of the present invention, the polymer raw material further includes an initiator and a solvent.

[0036] The initiator is selected from any one of an organic peroxide initiator or an azo initiator. The organic peroxide initiator is preferably benzoyl peroxide or tert-butyl peroxyvalerate; the azo initiator is preferably azobisisobutyronitrile or azobisisoheptanenitrile.

[0037] Furthermore, the initiator is preferably azobisisobutyronitrile.

[0038] Furthermore, the mass percentage of the initiator in the polymer raw material is 0.1-5%, preferably 0.1-3%.

[0039] The solvent is a fluorine-containing solvent, preferably one or a mixed solvent of two or more of nonafluorobutyl ether, hexafluoropropylene trimer, perfluorohexanone and hydrofluoroether.

[0040] Furthermore, the solvent is preferably nonafluorobutyl ethyl ether.

[0041] In the present invention, the monomer raw materials refer to monomers participating in the polymerization reaction, such as siloxane hydroxy perfluoropolyether monomers, fluorine-free monomers, monomers containing epoxy groups, organic siloxane monomers, isocyanate monomers; the polymer raw materials refer to all raw materials required for the polymerization reaction, including monomer raw materials, initiators, solvents, etc.

[0042] In the present invention, methyl (meth)acrylate refers to methyl methacrylate and / or methyl acrylate. It can be inferred that other groups containing methyl in brackets have the same meaning. For example, n-butyl (meth)acrylate refers to n-butyl methacrylate and / or n-butyl acrylate.

[0043] The present invention provides a method for preparing the siloxane hydroxy perfluoropolyether monomer, the method comprising the following steps:

[0044] 1. reacting the double-terminal hydroxyl perfluoropolyether with allyl bromide so that it reacts with the hydroxyl group at one end and retains the hydroxyl group at the other end to obtain allyl hydroxyl perfluoropolyether;

[0045] 2. Under the catalysis of Castell, it undergoes a hydrosilylation reaction with hydrogen-containing siloxane to obtain a siloxane hydroxy perfluoropolyether monomer.

[0046] In a second aspect, the present invention provides a method for preparing the polymer, comprising the following steps: in an inert gas atmosphere, the monomer raw material is mixed with an initiator and a solvent, heated to 60-90° C., preferably 70-75° C., and stirred for reaction for 6-10 hours.

[0047] In a third aspect, the present invention provides a protective coating agent, comprising the polymer or the polymer prepared by the method. The protective coating agent may also contain other acceptable components of coating agents on the basis of the polymer.

[0048] In a fourth aspect, the present invention provides use of the coating agent in preparing a protective coating agent for electronic products.

[0049] Preferably, the prepared electronic product protective coating agent has the properties of water and oil repellency, moisture resistance, salt spray resistance, and acid and alkali resistance.

[0050] Preferably, the electronic product is selected from a Bluetooth headset, an electronic watch, a mobile phone, an MP4 and / or an MP3.

[0051] The present invention utilizes siloxane hydroxy perfluoropolyether monomer and acrylate to undergo free radical polymerization under the action of an initiator to obtain a fluorine-containing polymer. The key point of the reaction of the present invention is mainly the use of siloxane hydroxy perfluoropolyether monomer and epoxy-containing monomer, and its further advantages include the following aspects:

[0052] 1. The siloxane hydroxyl perfluoropolyether monomer of the present invention is a modified perfluoropolyether monomer, one end of which is terminated with siloxane, which can play the role of the interpenetrating network structure of fluorosilicone polymer, improve the shortcomings of fluorosilicone materials such as poor adhesion, low hardness, general strength, and difficulty in curing at room temperature, and can make the product more moisture-proof, water-repellent and oil-repellent, and have a higher contact angle; the other end of the modified perfluoropolyether monomer is terminated with hydroxyl, which can be used as a reactive group to combine with acrylate through isocyanate cross-linking, thereby improving the acid and alkali resistance, weather resistance and film adhesion of the polymer.

[0053] 2. The modified perfluoropolyether monomer of the present invention is used as a fluorine monomer to carry out free radical polymerization with a small amount of acrylate monomer, so that a thin layer of electronic protective agent with excellent moisture-proof, water-repellent and oil-repellent properties can be formed on the surface of electronic components, and at the same time, it has strong chemical corrosion resistance without affecting its related properties.

[0054] 3. Since the modified perfluoropolyether monomer of the present invention does not contain a perfluoroalkyl component, it is not restricted for use in any country in the world and has a wide range of applications.

[0055] 4. When epoxy-containing monomers are added as a coating, the coating film can be made not only impermeable to water and air and have extremely strong adhesion, but also improve the acid, alkali and organic solvent resistance, water resistance, radiation resistance and other properties.

[0056] Beneficial Effects

[0057] According to the above technical scheme, the present invention has the following advantages compared with the prior art:

[0058] 1. The present invention uses siloxane hydroxyl perfluoropolyether monomer as fluorine monomer, which is less toxic than perfluoroalkyl monomer and will not cause irreparable damage to the environment.

[0059] 2. Siloxane hydroxyl perfluoropolyether monomer plays the role of fluorosilicone polymer interpenetrating network structure, which can improve the shortcomings of fluorosilicone materials such as poor adhesion, low hardness and general strength, and make the product more moisture-proof, water-repellent and oil-repellent, and have a higher contact angle.

[0060] 3. One end of the siloxane hydroxyl perfluoropolyether monomer is hydroxyl terminated, and the hydroxyl terminated can be used as a reactive group to combine with acrylate through isocyanate cross-linking to improve the acid and alkali resistance, weather resistance and film adhesion of the polymer. DETAILED DESCRIPTION

[0061] The following examples and comparative examples are used to illustrate the present invention in detail, but are not intended to limit the scope of the present invention.

[0062] The present invention provides a polymer for protecting electronic products, wherein the polymer comprises raw materials in the mass percentage content shown in Table 1.

[0063] Table 1: Polymer raw material composition

[0064]

[0065] Preferably, the present invention further provides a polymer for protecting electronic products, wherein the polymer comprises raw materials in the mass percentage content shown in Table 2.

[0066] Table 2: Polymer raw material composition

[0067]

[0068] The present invention provides a polymer for protecting electronic products, and the preparation method thereof comprises the following steps:

[0069] Weigh the siloxane hydroxy perfluoropolyether monomer, fluorine-free monomer, epoxy group-containing monomer, organosiloxane monomer, isocyanate monomer, initiator and solvent, heat to 60-90° C., preferably 70-75° C., in a nitrogen environment, and stir to react for 6-10 hours.

[0070] Example 1

[0071] (1) Synthesis of siloxane hydroxy perfluoropolyether

[0072] Under nitrogen protection, add HOCH2CF2(OCF2)2(OCF2CF2) into a three-necked flask. 10 50 g of OCF2CH2OH (Mw = 2500 g / mol) and 1.64 g of potassium tert-butoxide were added, tert-butanol (150 mL) was added as the reaction solvent, and the mixture was stirred at 40 °C for 30 min. Allyl bromide (2.66 mL) was then added dropwise. The molar ratio of perfluoropolyether methanol, potassium tert-butoxide and allyl bromide was 1:1.6:1.2. The mixture was reacted at 40 °C for 6 h. After the reaction was completed, the reaction mixture was placed in a separatory funnel and washed with water. The lower layer of the sample was extracted with 200 mL of trifluorotrichloroethane. After the lower layer of liquid was taken out and rotary evaporated, allyl hydroxy perfluoropolyether was obtained: HOCH2CF2(OCF2)2(OCF2CF2) 10 OCF2CH2OCH2CH=CH2.

[0073] 2.44 g of trimethoxysilane and 50 g of the allyl hydroxy perfluoropolyether obtained above were added to a three-necked flask, and then 80 μL of Custer catalyst (Pt content is about 950 ppm) was added, and the reaction was stirred at 80 ° C for 8 hours. After the reaction was completed, anhydrous ethanol and fluorine solvent were added to the product and stirred rapidly for 10 minutes. Finally, phase extraction and vacuum distillation were performed to obtain siloxane hydroxy perfluoropolyether monomer:

[0074] HOCH2CF2(OCF2)2(OCF2CF2) 10OCF2CH2OCH2CH2CH2Si(OCH3)3.

[0075] (2) Preparation of polymer

[0076] Weigh the above-mentioned siloxane hydroxy perfluoropolyether monomer HOCH2CF2(OCF2)2(OCF2CF2) 10 33g of OCF2CH2OCH2CH2CH2Si(OCH3)3, 15g of methyl methacrylate, 4g of glycidyl methacrylate, 2g of vinyl trimethoxysiloxane, 2g of isocyanoethyl methacrylate, 1g of azobisisobutyronitrile and 130g of nonafluorobutyl ether were placed in a four-necked bottle, reacted at 72°C for 8h in a nitrogen environment, and then the nitrogen was turned off to terminate the reaction to obtain a polymer solution.

[0077] The polymer solution obtained in this embodiment can be used as an electronic protective coating.

[0078] Example 2

[0079] (1) Synthesis of siloxane hydroxy perfluoropolyether

[0080] HOCH2CF2(OCF2) 10 OCF2CH2OH was used as a raw material to synthesize a siloxane hydroxy perfluoropolyether monomer according to step (1) of Example 1:

[0081] HOCH2CF2(OCF2) 10 OCF2CH2OCH2CH2CH2Si(OCH3)3.

[0082] (2) Preparation of polymer

[0083] Weigh the above synthesized siloxane hydroxy perfluoropolyether monomer

[0084] HOCH2CF2(OCF2) 10 33g of OCF2CH2OCH2CH2CH2Si(OCH3)3, 15g of methyl methacrylate, 4g of glycidyl methacrylate, 2g of vinyl trimethoxysiloxane, 2g of isocyanoethyl methacrylate, 1g of azobisisobutyronitrile and 130g of nonafluorobutyl ether were placed in a four-necked bottle, reacted at 72°C for 8h in a nitrogen environment, and then the nitrogen was turned off to terminate the reaction to obtain a polymer solution.

[0085] The polymer solution obtained in this embodiment can be used as an electronic protective coating.

[0086] Example 3

[0087] (1) Synthesis of siloxane hydroxy perfluoropolyether

[0088] HOCH2CF2(OCF2)2(OCF2CF2) 10 (C3F6O)4OCF2CH2OH was used as a raw material to synthesize a siloxane hydroxy perfluoropolyether monomer according to step (1) of Example 1:

[0089] HOCH2CF2(OCF2)2(OCF2CF2) 10 (C3F6O)4OCF2CH2OCH2CH2CH2Si(OCH3)3.

[0090] (2) Preparation of polymer

[0091] Weigh the above synthesized siloxane hydroxy perfluoropolyether monomer

[0092] HOCH2CF2(OCF2)2(OCF2CF2) 10 33 g of (C3F6O)4OCF2CH2OCH2CH2CH2Si(OC H3)3, 15 g of methyl methacrylate, 4 g of glycidyl methacrylate, 2 g of vinyl trimethoxysiloxane, 2 g of isocyanoethyl methacrylate, 1 g of azobisisobutyronitrile and 130 g of nonafluorobutyl ether were placed in a four-necked bottle, reacted at 72 °C in a nitrogen environment for 8 h, and then the nitrogen was turned off to terminate the reaction to obtain a polymer solution.

[0093] The polymer solution obtained in this embodiment can be used as an electronic protective coating.

[0094] Example 4

[0095] (1) Synthesis of siloxane hydroxy perfluoropolyether

[0096] HOCH2CF2(OCF2) 10 OCF2CH2OH was used as a raw material to synthesize a siloxane hydroxy perfluoropolyether monomer according to step (1) of Example 1:

[0097] HOCH2CF2(OCF2) 10 OCF2CH2OCH2CH2CH2Si(OCH3)3.

[0098] (2) Preparation of polymer

[0099] Weigh the above synthesized siloxane hydroxy perfluoropolyether monomer

[0100] HOCH2CF2(OCF2) 1033g of OCF2CH2OCH2CH2CH2Si(OCH3)3, 15g of butyl methacrylate, 4g of glycidyl methacrylate, 2g of vinyl trimethoxysiloxane, 2g of isocyanoethyl methacrylate, 1g of azobisisobutyronitrile and 130g of nonafluorobutyl ether were placed in a four-necked bottle, reacted at 72°C for 8h in a nitrogen environment, and then the nitrogen was turned off to terminate the reaction to obtain a polymer solution.

[0101] The polymer solution obtained in this embodiment can be used as an electronic protective coating.

[0102] Example 5

[0103] (1) Synthesis of siloxane hydroxy perfluoropolyether

[0104] HOCH2CF2(OCF2) 10 OCF2CH2OH was used as a raw material to synthesize a siloxane hydroxy perfluoropolyether monomer according to step (1) of Example 1:

[0105] HOCH2CF2(OCF2) 10 OCF2CH2OCH2CH2CH2Si(OCH3)3.

[0106] (2) Preparation of polymer

[0107] Weigh the above synthesized siloxane hydroxy perfluoropolyether monomer

[0108] HOCH2CF2(OCF2) 10 33g of OCF2CH2OCH2CH2CH2Si(OCH3)3, 15g of methyl methacrylate, 4g of allyl glycidyl ether, 2g of vinyl trimethoxysiloxane, 2g of isocyanoethyl methacrylate, 1g of azobisisobutyronitrile and 130g of nonafluorobutyl ether were placed in a four-necked bottle, reacted at 72°C in a nitrogen environment for 8h, and then the nitrogen was turned off to terminate the reaction to obtain a polymer solution.

[0109] The polymer solution obtained in this embodiment can be used as an electronic protective coating.

[0110] Example 6

[0111] (1) Synthesis of siloxane hydroxy perfluoropolyether

[0112] HOCH2CF2(OCF2) 10 OCF2CH2OH was used as a raw material to synthesize a siloxane hydroxy perfluoropolyether monomer according to step (1) of Example 1:

[0113] HOCH2CF2(OCF2) 10 OCF2CH2OCH2CH2CH2Si(OCH3)3.

[0114] (2) Preparation of polymer

[0115] Weigh the above synthesized siloxane hydroxy perfluoropolyether monomer

[0116] HOCH2CF2(OCF2) 10 33g of OCF2CH2OCH2CH2CH2Si(OCH3)3, 15g of methyl methacrylate, 4g of glycidyl methacrylate, 2g of vinyltrimethoxysiloxane, 2g of isocyanocyclohexene, 1g of azobisisobutyronitrile and 130g of nonafluorobutyl ether were placed in a four-necked bottle, reacted at 72°C for 8h in a nitrogen environment, and then the nitrogen was turned off to terminate the reaction to obtain a polymer solution.

[0117] The polymer solution obtained in this embodiment can be used as an electronic protective coating.

[0118] Comparative Example 1

[0119] Weigh 33 g of perfluoroalkyl methacrylate monomer CF3(CF2)5-CH2-CH2-O-(C=O)-CH=CH2, 15 g of methyl methacrylate, 4 g of glycidyl methacrylate, 2 g of vinyl trimethoxysiloxane, 2 g of isocyanoethyl methacrylate, 1 g of azobisisobutyronitrile and 130 g of nonafluorobutyl ether into a four-necked bottle, react at 72°C in a nitrogen environment for 8 h, then turn off the nitrogen to terminate the reaction, and the resulting polymer is used as an electronic protective coating.

[0120] Comparative Example 2

[0121] Weigh the siloxane hydroxy perfluoropolyether monomer HOCH2CF2 (OCF2) 10 33 g of OCF2CH2OCH2CH2CH2Si(OCH3)3, 1 g of azobisisobutyronitrile and 130 g of nonafluorobutyl ether were placed in a four-necked bottle and reacted at 72°C for 8 h in a nitrogen environment. The nitrogen was then turned off to terminate the reaction. The obtained polymer was used as an electronic protective coating agent.

[0122] Comparative Example 3

[0123] Weigh the siloxane hydroxy perfluoropolyether monomer HOCH2CF2 (OCF2) 10 33 g of OCF2CH2OCH2CH2CH2Si(OCH3)3, 15 g of methyl methacrylate, 2 g of vinyl trimethoxysiloxane, 2 g of isocyanoethyl methacrylate, 1 g of azobisisobutyronitrile and 130 g of nonafluorobutyl ether were placed in a four-necked bottle and reacted at 72°C for 8 h in a nitrogen environment. The nitrogen was then turned off to terminate the reaction. The resulting polymer was used as an electronic protective coating.

[0124] Experimental Example 1. Water and oil repellency

[0125] The water and oil repellency of the copper foil on the test piece was evaluated using a contact angle meter. The PCB board was ultrasonically cleaned in acetone for 30 minutes, then cleaned and dried with HFE 7100 solvent, and then immersed in the HFE7100 solution (2.0 weight %) of each polymer obtained in Examples 1 to 6 and Comparative Examples 1 to 3, and dried at room temperature for 30 minutes to obtain a sample. The JC2000D4 contact angle meter produced by Shanghai Zhongchen Digital Technology Co., Ltd. was used to measure the static contact angle of water with a droplet volume of 2μL and the static contact angle of hexadecane with a droplet volume of 2μL for each sample, and the results are listed in Table 3 below.

[0126] Table 3

[0127]

[0128] From the results in Table 3, it can be seen that the polymers prepared in Examples 1 to 6 exhibit large static contact angles to water, and it can be confirmed that they have excellent water- and oil-repellent properties.

[0129] Experimental Example 2. Evaluation method of moisture resistance

[0130] The moisture-proof test is carried out in accordance with GB-2423.3-81 "Stationary damp heat test method for electrical products":

[0131] The test temperature is 40±2℃, the relative humidity is (93±3)%RH, and the test period is 10 days;

[0132] The moisture-proof test uses KTHB-415TBS constant temperature and humidity test machine;

[0133] The contact resistance test was evaluated using the TH2512B intelligent DC low resistance tester;

[0134] The test piece was a PCB circuit board from a commercially available simple electronic stopwatch. The moisture-proof performance of the electronic coating agent was determined by the changes in the circuit board surface appearance and contact resistance before and after the experiment. The results are listed in Table 4 below.

[0135] Table 4

[0136] Example Appearance changes Contact resistance value / Ω Example 1 No change <![CDATA[2.3*10 13 ]]> Example 2 No change <![CDATA[4.5*10 15 ]]> Example 3 No change <![CDATA[7.8*10 13 ]]> Example 4 No change <![CDATA[3.5*10 13 ]]> Example 5 No change <![CDATA[2.6*10 14 ]]> Example 6 No change <![CDATA[4.0*10 14 ]]> Comparative Example 1 Mild corrosion <![CDATA[2.3*10 10 ]]> Comparative Example 2 Moderate corrosion <![CDATA[5.2*10 6 ]]> Comparative Example 3 Mild corrosion <![CDATA[3.5*10 9 ]]>

[0137] From the results in Table 4, it can be seen that after 10 days of constant temperature and humidity test, the coating agents prepared in Examples 1 to 6 have relatively excellent moisture-proof properties.

[0138] Experimental Example 3. Evaluation method of salt spray resistance

[0139] Chemical corrosion resistance is evaluated using the salt spray test (GB / T 2423.17-2008):

[0140] Angle of test piece: 20±5° relative to vertical axis. Concentration of salt water (NaCl): 5±1% (mass ratio), pH 6.5-7.2;

[0141] The saturated air temperature is 57±1℃, and the salt water test chamber temperature is 35±1℃;

[0142] The experimental equipment is TK-YW120PL salt spray test chamber;

[0143] A polished copper substrate with a size of 2.0×20×50 mm was used as the substrate, and was immersed in a 2% HFE7100 solution of each polymer once, and then taken out and dried at room temperature for 30 minutes. After the salt water spray, the appearance after 72 hours of continuous spraying test was evaluated in four processes of O (no change = no corrosion), + (slight corrosion), ++ (moderate corrosion), and +++ (severe), and the results are listed in Table 5.

[0144] Table 5

[0145] Example 24h Corrosion Degree 48h Corrosion Degree 72h Corrosion Degree Example 1 O O O Example 2 O O O Example 3 O O O Example 4 O O O Example 5 O O O Example 6 O O O Comparative Example 1 O + ++ Comparative Example 2 + ++ +++ Comparative Example 3 + ++ ++ Blank copper sheet +++ +++ +++

[0146] From the salt spray resistance test results in Table 5, it can be seen that the coating agents prepared in Examples 1 to 6 have relatively excellent salt spray resistance.

[0147] Experimental Example 4. Evaluation method of acid and alkali resistance

[0148] The acid and alkali resistance test method of this experiment adopts the B immersion method in the national standard GB / T 9274-1988, and the strong acid and strong alkali test solutions with pH values ​​of 2 and 12 are prepared, and sufficient amounts of strong acid and strong alkali test solutions are poured into appropriate transparent containers. A polished copper substrate with a size of 2.0×20×50mm is used as a substrate, immersed in a 2% HFE 7100 solution of each polymer once, taken out and dried at room temperature for 30 minutes. The treated copper sheet is placed in a container and completely immersed in the test solution, the lid is covered, the corrosion condition is observed, and the time when the corrosion starts is recorded. The results are listed in Table 6.

[0149] Table 6

[0150]

[0151]

[0152] From the results in Table 6, it can be seen that the coating agents of Examples 1-6 of the present invention have significantly higher resistance to strong acids and strong alkalis than the comparative examples.

[0153] The above are only specific embodiments of the present invention, but the technical features of the present invention are not limited thereto. Any simple changes, equivalent replacements or modifications made based on the present invention to achieve basically the same technical effects are all included in the protection scope of the present invention.

Claims

1. A polymer, characterized in that The polymer is polymerized from the following monomer raw materials: Siloxane hydroxy perfluoropolyether monomers, epoxy group-containing monomers, fluorine-free monomers, organosiloxane monomers and isocyanate monomers; The siloxane hydroxyl perfluoropolyether monomer is shown in formula (I): HOCH2CF2-Rf-O-CF2CH2O-X-Si(OR)3(I); Wherein, Rf represents -(C4F8O) a -(C3F6O) b -(C2F4O) c -(CF2O) d -, a, b, c and d are each independently an integer within the range of 0 to 200, and the sum of a, b, c, d is at least 1; X is a linear or branched C3-C6 aliphatic group; R is a linear or branched C1-C6 aliphatic group; The epoxy group-containing monomer refers to a monomer containing an epoxy group and capable of being polymerized with acrylate; In the monomer raw materials, the mass ratio of the siloxane hydroxy perfluoropolyether monomer, the fluorine-free monomer, the epoxy group-containing monomer, the organic siloxane monomer and the isocyanate monomer is (1-40):(2-20):(0.5-8):(0.5-5):(0.5-5).

2. The polymer according to claim 1, characterized in that In Rf in the formula (I), a, b, c, and d are each independently an integer within the range of 0 to 40, and the sum of a, b, c, and d is at least 1.

3. The polymer according to claim 2, characterized in that In Rf in the formula (I), a, b, c, and d are each independently an integer within the range of 0 to 20, and the sum of a, b, c, and d is at least 1.

4. The polymer according to claim 1, characterized in that The epoxy group-containing monomer is selected from one or both of glycidyl methacrylate and allyl glycidyl ether.

5. The polymer according to any one of claims 1 to 4, characterized in that The mass ratio of the silicone hydroxy perfluoropolyether monomer to the epoxy group-containing monomer is (15-35):(1-4).

6. The polymer according to claim 5, characterized in that In the monomer raw material, the mass ratio of the siloxane hydroxy perfluoropolyether monomer, the fluorine-free monomer, the epoxy group-containing monomer, the organic siloxane monomer and the isocyanate monomer is (15-35):(6-10):(1-4):(0.5-3):(0.5-3).

7. The polymer according to claim 6, characterized in that The fluorine-free monomer is a compound having one carbon-carbon double bond; And / or, the organosiloxane monomer is an organosiloxane containing an amino group, a mercapto group or a double bond and capable of undergoing polymerization reaction with acrylate; and / or, the isocyanate monomer is a vinyl-terminated isocyanate capable of undergoing polymerization reaction with acrylate.

8. The polymer according to claim 7, characterized in that The fluorine-free monomer is selected from one or more of ethylene, vinyl acetate, vinyl halide, vinylidene halide, acrylonitrile, styrene, methyl (meth)acrylate, n-butyl methacrylate, tert-butyl methacrylate, isobornyl (meth)acrylate, benzyl (meth)acrylate, polyethylene glycol (meth)acrylate, polypropylene glycol (meth)acrylate, methoxy polyethylene glycol (meth)acrylate, methoxy polypropylene glycol (meth)acrylate and vinyl alkyl ether.

9. The polymer according to claim 8, characterized in that The vinyl halide is vinyl chloride.

10. The polymer according to claim 8, characterized in that The vinylidene halide is vinylidene chloride.

11. The polymer according to claim 7, characterized in that The organosiloxane monomer is selected from one or more of vinyl trimethoxysilane, vinyl triethoxysilane, aminopropyl triethoxysilane, mercaptopropyl trimethoxysilane, methacryloxypropyl trimethylsilane, vinyl silicone oil and hydrogen-containing silicone oil.

12. The polymer according to claim 7, characterized in that The isocyanate is selected from one or more of isocyanoethyl methacrylate, 2-chloroallyl isothiocyanate, methacryloyl isocyanate and isocyanocyclohexene.

13. The method for preparing a polymer according to any one of claims 1 to 12, characterized in that: Under an inert gas atmosphere, the monomer raw material is stirred and reacted at 60-90° C. for 6-10 hours.

14. The method according to claim 13, characterized in that The monomer raw materials are stirred and reacted at 70-75°C.

15. The method according to claim 13, characterized in that The stirring reaction system also contains an initiator and a solvent.

16. A coating agent, characterized in that: A polymer comprising the polymer described in any one of claims 1 to 12 or a polymer prepared by the method described in any one of claims 13 to 15.

17. Use of the polymer according to any one of claims 1 to 12 or the coating agent according to claim 16 in the preparation of protective coating agents for electronic products.

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