UV-moisture dual-curing three-proofing adhesive as well as preparation method and application thereof

Abstract

The invention provides a UV-moisture dual-curing three-proofing adhesive as well as a preparation method and application thereof. The UV-moisture dual-curing three-proofing adhesive comprises the following components in parts by weight: 40-60 parts of fluorine-containing polyurethane acrylate resin; 30-50 parts of a reactive diluent, 2-8 parts of a photoinitiator and 0.1-0.5 part of a polymerization inhibitor; and 1-3 parts of a dehydrating agent. The three-proofing adhesive provided by the invention has excellent wettability and corrosion resistance, has good adhesive force and flexibility, can realize UV and moisture dual curing, and can be used for bonding electronic circuit boards.

Description

Technical Field

[0001] The invention belongs to the technical field of adhesives, and in particular relates to a UV-moisture dual-curing three-proof adhesive and a preparation method and application thereof. Background Art

[0002] With the rapid development of modern electronic technology, the service environment of electronic equipment and its components is becoming increasingly complex. For example, electronic equipment serving in the fields of spacecraft, aviation and ships often needs to face special corrosive environments such as high temperature, high humidity and high salt spray. Printed circuit boards are key components of modern electronic equipment, so the three-proof protection of their surface is particularly important. During the manufacturing and use of printed circuit boards (PCBs), they are subject to chemical corrosion, dust adhesion, water vapor penetration, and mechanical damage, which will cause corrosion, softening, deformation, and then short circuit and breakdown, affecting their service life and even causing significant losses. Electronic protective coating is a transparent coating agent formed on the surface of electronic components to protect electronic components from damage in humid, corrosive environments, as well as various chemicals, dust, high and low temperature and other harsh environmental impacts. This coating was originally used in high-end aerospace and military integrated circuit industries, but with the rapid development of 5G communications, its application in civilian applications such as mobile phones, tablets, car central control, and various external display screens has shown an increasing trend year by year.

[0003] Therefore, developing a polyurethane three-proof adhesive with excellent high temperature resistance, corrosion resistance and wetting properties, good adhesion and flexibility, and capable of dual curing by UV and moisture, which can be used for bonding electronic circuit boards, is of great significance to the development of three-proof adhesive. Summary of the invention

[0004] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a UV-moisture dual-curing three-proof adhesive and its preparation method and application. The three-proof adhesive of the present invention has excellent wetting performance and corrosion resistance, and has good adhesion and flexibility, can achieve UV and moisture dual curing, and can be used for electronic circuit board bonding.

[0005] To achieve this object, the present invention adopts the following technical solutions:

[0006] In one aspect, the present invention provides a UV-moisture dual-curing conformal adhesive, wherein the UV-moisture dual-curing conformal adhesive comprises the following components in parts by weight:

[0007]

[0008] The fluorine-containing polyurethane acrylate resin has the following structure:

[0009]

[0010] Wherein, R1, R2, R3, and R4 are independently selected from -N=C=O, R5 is selected from F-substituted alkyl, R6 is selected from the residue of hydroxy acrylate; and at least one of R1, R2, R3 and R4 is selected from At least one selected from n is an integer of 8-20 (e.g., 8, 9, 10, 11, 12, 13, 15, 16, 18 or 20).

[0011] In the present invention, the fluorine-containing polyurethane acrylate resin contains NCO groups and double bond groups, which can realize moisture and UV dual curing, solving the problem that the shadow part cannot be cured during UV curing; and the fluorine-containing alkyl chain segment in the resin can reduce the surface energy, so that the prepared three-proof adhesive has a lower surface tension, and the wettability of the three-proof adhesive is improved; at the same time, during the curing process, the fluorine-containing chain segment will migrate to the surface of the material, reduce the surface energy of the material, so that the surface of the cured three-proof adhesive has good hydrophobic properties, thereby obtaining excellent waterproof, mildew-proof, and corrosion-resistant properties, which can effectively prevent the erosion of water vapor, mildew, solvents, etc. on the circuit board and increase the service life of the circuit board.

[0012] Preferably, the F-substituted alkyl group is selected from

[0013] Preferably, the residue of the hydroxyacrylate is selected from

[0014] Preferably, the fluorine-containing polyurethane acrylate resin is obtained by reacting hexamethylene diisocyanate-based polyisocyanate, polyethylene glycol, hydroxy acrylate, and monohydroxy fluorine-containing monomer.

[0015] Preferably, the hexamethylene diisocyanate-based polyisocyanate is a hexamethylene diisocyanate trimer.

[0016] Preferably, the hexamethylene diisocyanate-based polyisocyanate is selected from one of HT-90, HT-100, HB-100, HT-300 or HT-600 of Wanhua Chemical.

[0017] In the present invention, the structure of the polyethylene glycol is n is an integer from 8 to 12.

[0018] Preferably, the polyethylene glycol is selected from one of DL1000, DL-400 of Bluestar Dongda and PCL205U, PCL205, PCL208 or PCL210 of Daicel.

[0019] Preferably, the acrylate is selected from one or a combination of at least two of hydroxyethyl methacrylate, hydroxypropyl methacrylate or pentaerythritol triacrylate.

[0020] Preferably, the monohydroxy fluorine-containing monomer is selected from at least one of perfluorohexylethyl alcohol or 2-perfluorooctylethanol (such as perfluorohexylethyl alcohol and 2-perfluorooctylethanol produced by Liaoning Hengtong Fuxin Fluorine Chemical Co., Ltd.), perfluorohexylethyl alcohol or 2-perfluorooctylethanol.

[0021] Preferably, the reaction is carried out in the presence of a catalyst.

[0022] Preferably, the catalyst is dibutyltin dilaurate.

[0023] Preferably, the reaction is carried out in the presence of a polymerization inhibitor.

[0024] Preferably, the polymerization inhibitor is selected from one or a combination of at least two of hydroquinone, p-hydroxyanisole, p-benzoquinone and naphthoquinone.

[0025] Preferably, the reaction is carried out in the presence of an antioxidant.

[0026] Preferably, the antioxidant is selected from one or a combination of at least two of 1076, BHT (2,6-di-tert-butyl-4-methylphenol) or TPP (triphenyl phosphite).

[0027] Preferably, the molar ratio of the hexamethylene diisocyanate-based polyisocyanate to the polyethylene glycol is (1-1.2):(0.4-0.6), for example 1:0.4, 1:0.45, 1:0.5, 1:0.55, 1:0.6, 1.1:0.4, 1.1:0.45, 1.1:0.5, 1.1:0.55, 1.1:0.6, 1.2:0.4, 1.2:0.45, 1.2:0.5, 1.2:0.55 or 1.2:0.6.

[0028] Preferably, the molar ratio of the hexamethylene diisocyanate-based polyisocyanate to the hydroxy acrylate is (1-1.2):(0.8-1), for example, 1:0.8, 1:0.85, 1:0.9, 1:0.95, 1:1, 1.1:0.8, 1.1:0.85, 1.1:0.9, 1.1:0.95, 1.1:1, 1.2:0.8, 1.2:0.85, 1.2:0.9, 1.2:0.95, 1.2:1.

[0029] Preferably, the molar ratio of the hexamethylene diisocyanate-based polyisocyanate to the monohydroxy fluorinated monomer is (1-1.2):(0.4-0.6), for example, 1:0.4, 1:0.45, 1:0.5, 1:0.55, 1:0.6, 1.1:0.4, 1.1:0.45, 1.1:0.5, 1.1:0.55, 1.1:0.6, 1.2:0.4, 1.2:0.45, 1.2:0.5, 1.2:0.55 or 1.2:0.6.

[0030] Preferably, the reaction specifically comprises the following steps:

[0031] (1) mixing hexamethylene diisocyanate-based polyisocyanate and polyethylene glycol, as well as a polymerization inhibitor and an antioxidant, reacting, adding a catalyst, and continuing the reaction;

[0032] (2) Adding hydroxy acrylate and monohydroxy fluorine-containing monomer to the reaction solution obtained in step (1), reacting to obtain the fluorine-containing polyurethane acrylate resin.

[0033] Preferably, after the mixing in step (1), the temperature is raised to 65° C. and reacted for 1 hour, then the temperature is raised to 75° C. and continued to react for 2 hours. After the catalyst is added, the reaction is continued for 2 hours.

[0034] Preferably, the reaction temperature in step (2) is 75° C. and the reaction time is 1-2 h.

[0035] Preferably, the reactions of step (1) and step (2) are carried out under nitrogen protection.

[0036] Preferably, the reactive diluent is selected from one or a combination of at least two of isobornyl acrylate, isobornyl methacrylate or isooctyl acrylate.

[0037] Preferably, the photoinitiator is selected from one or a combination of at least two of initiators 651, 184, 1173, 500, 907, TPO or LTM.

[0038] Preferably, the inhibitor in the formula of the UV-moisture dual-curing conformal adhesive is selected from one or a combination of at least two of hydroquinone, p-hydroxyanisole, p-benzoquinone or naphthoquinone.

[0039] Preferably, the dehydrating agent is p-toluenesulfonyl isocyanate.

[0040] On the other hand, the present invention provides a method for preparing the UV-moisture dual-curing conformal adhesive as described above, the preparation method comprising the following steps:

[0041] The active diluent and the photoinitiator are mixed, and then the fluorine-containing polyurethane acrylate resin, the polymerization inhibitor, and the dehydrating agent are added to the mixture and mixed to obtain the UV-moisture dual-curing three-proof adhesive.

[0042] Preferably, the mixing is performed at 20-30°C (eg, 20°C, 23°C, 25°C, 28°C or 30°C).

[0043] Preferably, the mixing is performed under stirring.

[0044] Preferably, the mixing is performed under nitrogen protection.

[0045] Preferably, the time for mixing the reactive diluent and the photoinitiator is 0.5 to 1 h, for example, 0.5 h, 0.6 h, 0.7 h, 0.8 h, 0.9 h or 1 h.

[0046] Preferably, the fluorine-containing polyurethane acrylate resin, polymerization inhibitor and dehydrating agent are added to the mixture and mixed for 0.5 to 1 h, for example, 0.5 h, 0.6 h, 0.7 h, 0.8 h, 0.9 h or 1 h.

[0047] On the other hand, the present invention provides the use of the UV-moisture dual-curing three-proof adhesive as described above in the bonding of electronic circuit boards.

[0048] Compared with the prior art, the present invention has the following beneficial effects:

[0049] The UV-moisture dual-curing three-proof adhesive of the present invention uses a fluorine-containing polyurethane acrylate resin containing an NCO group and a double bond group, so that moisture and UV dual curing can be achieved, and the problem that the shadow part cannot be cured during UV curing is solved; the F alkyl group in the resin has extremely low surface energy, so that the three-proof adhesive has a lower surface tension and improves the wettability of the three-proof adhesive; at the same time, during the curing process, the fluorine-containing chain segment will migrate to the surface of the material, reduce the surface energy of the material, and make the surface of the cured three-proof adhesive have good hydrophobicity, thereby obtaining excellent waterproofness, mildew resistance, and corrosion resistance, which can effectively prevent the corrosion of water vapor, mildew, solvents, etc. to the circuit board and increase the service life of the circuit board. DETAILED DESCRIPTION

[0050] The technical solution of the present invention is further described below by specific implementation methods. It should be understood by those skilled in the art that the embodiments are only to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0051] Unless otherwise specified, the reagents, methods and equipment used in the present invention are conventional reagents, methods and equipment in the art. Unless otherwise specified, the reagents and materials used in the present invention are commercially available.

[0052] Preparation Example 1

[0053] 1 mol HT-600, 0.5 mol PCL208, 0.02% inhibitor benzoquinone, and 0.02% antioxidant 1076 were added to a four-necked flask with a thermometer, stirred evenly, heated to 65°C for reaction for 1 hour, then heated to 75°C for continued reaction for 2 hours, 0.01% catalyst dibutyltin dilaurate was added, and the reaction was continued for 2 hours, and then the NCO value was tested. When the NCO value reached the theoretical value, 1 mol of hydroxyethyl acrylate and 1 mol of perfluorobutanol were added, and the reaction was continued for 1 hour until the NCO value reached the theoretical value and tended to be stable, the reaction was stopped, and the temperature was lowered to 40°C for discharge to obtain a homemade UV-moisture dual-curing fluorinated polyurethane acrylate resin.

[0054] Preparation Example 2

[0055] 1 mol HT-600, 0.5 mol PCL208, 0.02% inhibitor naphthoquinone and 0.02% antioxidant BHT were added into a four-necked flask with a thermometer, stirred evenly, heated to 65°C for reaction for 1 hour, then heated to 75°C for reaction for 2 hours, 0.01% catalyst dibutyltin dilaurate was added, the reaction was continued for 2 hours, and the NCO value was then tested. When the NCO value reached the theoretical value, 1 mol hydroxyethyl acrylate and 1 mol perfluorobutyl alcohol were added, the reaction was continued for 2 hours, until the NCO value reached the theoretical value and tended to be stable, the reaction was stopped, the temperature was lowered to 40°C for discharge, and the self-made UV-moisture dual-curing fluorinated polyurethane acrylate resin was obtained.

[0056] Preparation Example 3

[0057] 1 mol HT-600, 0.5 mol PCL208, 0.02% inhibitor hydroquinone, and 0.02% antioxidant TPP were added to a four-necked flask with a thermometer, stirred evenly, heated to 65°C for reaction for 1 hour, then heated to 75°C for further reaction for 2 hours, 0.01% catalyst dibutyltin dilaurate was added, and the reaction was continued for 2 hours, and then the NCO value was tested. When the NCO value reached the theoretical value, 1 mol of hydroxyethyl acrylate and 1 mol of perfluorohexylethyl alcohol were added, and the reaction was continued for 1-2 hours until the NCO value reached the theoretical value and tended to be stable, the reaction was stopped, and the temperature was lowered to 40°C for discharge to obtain a self-made UV-moisture dual-curing fluorinated polyurethane acrylate resin.

[0058] Preparation Example 4

[0059] 1 mol HT-600, 0.5 mol PCL208, 0.02% inhibitor p-hydroxyanisole and 0.02% antioxidant 1076 were added to a four-necked flask with a thermometer, stirred evenly, heated to 65°C for reaction for 1 hour, then heated to 75°C for further reaction for 2 hours, 0.01% catalyst dibutyltin dilaurate was added, the reaction was continued for 2 hours, and the NCO value was then tested. When the NCO value reached the theoretical value, 1 mol of hydroxyethyl acrylate and 1 mol of 2-perfluorooctylethanol were added, the reaction was continued for 1 hour, until the NCO value reached the theoretical value and tended to be stable, the reaction was stopped, the temperature was lowered to 40°C for discharge, and the self-made UV-moisture dual-curing fluorinated polyurethane acrylate resin was obtained.

[0060] Preparation of Comparative Example 1 (Fluorine-free Polyurethane Acrylate Resin)

[0061] 1 mol HT-600, 0.5 mol PCL208, 0.02% inhibitor benzoquinone and 0.02% antioxidant 1076 were added into a four-necked flask with a thermometer, stirred evenly, heated to 65°C for reaction for 1 hour, then heated to 75°C for reaction for 2 hours, added with 0.01% catalyst dibutyltin dilaurate, and continued to react for 2 hours, then tested the NCO value. When the NCO value reached the theoretical value, added with 1 mol hydroxyethyl acrylate, continued to react for 1 hour, until the NCO value reached the theoretical value and tended to be stable, stopped the reaction, cooled to 40°C and discharged to obtain a self-made UV-moisture dual-curing fluorinated polyurethane acrylate resin.

[0062] Preparation of Comparative Example 2 (NCO-free fluorinated polyurethane acrylate resin)

[0063] 1 mol HT-600, 0.5 mol PCL208, 0.02% inhibitor and 0.02% antioxidant were added into a four-necked flask with a thermometer, stirred evenly, heated to 65°C for reaction for 1 hour, then heated to 75°C for reaction for 2 hours, added with 0.01% catalyst, and continued to react for 2 hours, then tested the NCO value. When the NCO value reached the theoretical value, added with 2 mol perfluorohexylethyl alcohol and 2 mol hydroxyethyl acrylate, and continued to react for 2 hours until the NCO value reached the theoretical value and tended to be stable, stopped the reaction, cooled to 40°C and discharged to obtain a self-made UV-moisture dual-curing fluorinated polyurethane acrylate resin.

[0064] Preparation of Comparative Example 3 (Fluorine-containing polyurethane acrylate resin without carbon-carbon double bonds)

[0065] 1 mol HT-600, 0.5 mol PCL208, 0.02% inhibitor benzoquinone, and 0.02% antioxidant 1076 were added to a four-necked flask with a thermometer, stirred evenly, heated to 65°C for reaction for 1 hour, then heated to 75°C for continued reaction for 2 hours, 0.01% catalyst dibutyltin dilaurate was added, and the reaction was continued for 2 hours, and then the NCO value was tested. When the NCO value reached the theoretical value, 1 mol perfluorohexylethyl alcohol was added, and the reaction was continued for 1 hour until the NCO value reached the theoretical value and tended to be stable, the reaction was stopped, and the temperature was reduced to 40°C for discharge to obtain a self-made UV-moisture dual-curing fluorinated polyurethane acrylate resin.

[0066] Examples 1 to 7

[0067] This embodiment provides a series of UV-moisture dual-curing conformal adhesives, which are prepared according to a method comprising the following steps:

[0068] According to the formula described in Table 1, the active diluent and photoinitiator are added to the reactor, the temperature is controlled at 25°C, N2 is passed for protection, and stirring is performed for 1 hour until the stirring is uniform; then the homemade fluorine-containing polyurethane acrylate resin, inhibitor, and dehydrating agent are added, and stirring is continued for 1 hour until the stirring is uniform. The entire stirring process is protected by N2, and the UV-moisture dual-curing three-proof adhesive described in this application can be obtained.

[0069] Table 1 Raw material formula of Examples 1 to 7 (parts by weight)

[0070]

[0071] Comparative Example 1

[0072] This comparative example provides a sealant, which is prepared according to the method of Example 3. The difference from Example 3 is that the fluorine-containing polyurethane acrylate resin is replaced by an equal weight of the fluorine-free polyurethane acrylate resin prepared in Preparation Comparative Example 1.

[0073] Comparative Example 2

[0074] This comparative example provides a sealant, which is prepared according to the method of Example 3. The difference from Example 3 is that the fluorine-containing polyurethane acrylate resin is replaced by an equal weight of the polyurethane acrylate resin without NCO group prepared in Preparation Comparative Example 2.

[0075] Comparative Example 3

[0076] This comparative example provides a sealant, which is prepared according to the method of Example 3. The difference from Example 3 is that the fluorine-containing polyurethane acrylate resin is replaced by an equal weight of the fluorine-containing polyurethane acrylate resin without carbon-carbon double bonds prepared in Comparative Example 3.

[0077] Performance Testing

[0078] The performance of the three-proof adhesive obtained in the above examples and comparative examples was tested. The specific test items and test conditions are shown in Table 2:

[0079] 365nm LED curing conditions: UV curing is performed using a 365nm wavelength LED lamp with a radiation intensity of 700mW / cm 2 .

[0080] Moisture curing conditions: Place it in a room with constant temperature and humidity (23±2°C, 50±10%RH) for 48 hours in absolute light avoidance.

[0081] The test conditions for adhesion, contact angle, acid resistance, alkali resistance and salt spray resistance are: UV curing energy is 6000mJ / cm 2 , then moisture cure for 72h.

[0082] Table 2

[0083]

[0084]

[0085] The test results are shown in Table 3.

[0086] Table 3 Test results of embodiments and comparative examples

[0087]

[0088]

[0089] From the above results, it can be seen that the UV-moisture dual-curing three-proof glue prepared by the present invention has moderate viscosity, good moisture and UV curing surface drying performance, can effectively solve the problem that the shadow part cannot be cured during UV curing, and the adhesion can reach level 0, which has a good wetting effect on PCB. The self-made fluorine-containing polyurethane acrylate resin containing NCO groups and double bond groups is used to reduce the surface tension of the three-proof glue and improve the wettability of the three-proof glue; at the same time, during the curing process, the fluorine-containing chain segment migrates to the surface of the material, reducing the surface energy of the material; after curing, the water contact angle of the three-proof glue can reach more than 89°, and the water absorption rate is reduced to less than 1.2%, indicating that the material has excellent waterproof properties; at the same time, after acid and alkali immersion and salt spray treatment for 168 hours, the surface of the three-proof glue is not damaged, indicating that the three-proof glue prepared by the present invention has excellent corrosion resistance, which can effectively avoid the erosion of water vapor, mold, solvents, etc. on the circuit board and increase the service life of the circuit board.

[0090] The applicant declares that the present invention uses the above-mentioned embodiments to illustrate the UV-moisture dual-curing three-proof adhesive and its preparation method and application, but the present invention is not limited to the above-mentioned embodiments, that is, it does not mean that the present invention must rely on the above-mentioned embodiments to be implemented. Those skilled in the art should understand that any improvement of the present invention, equivalent replacement of various raw materials of the product of the present invention, addition of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

Claims

1. A UV-moisture dual-curing conformal adhesive, characterized in that: The UV-moisture dual-curing anti-corrosion adhesive comprises the following components in parts by weight: The fluorine-containing polyurethane acrylate resin has the following structure: Wherein, R1, R2, R3, and R4 are independently selected from - N ＝ C ＝ O. R5 is selected from F-substituted alkyl, R6 is selected from the residue of hydroxy acrylate; and at least one of R1, R2, R3 and R4 is selected from At least one selected from n is an integer from 8 to 20.

2. The UV-moisture dual-curing conformal adhesive according to claim 1, characterized in that: The F-substituted alkyl group is selected from Preferably, the residue of the hydroxyacrylate is selected from 3. The UV-moisture dual-curing conformal adhesive according to claim 1 or 2, characterized in that: The fluorine-containing polyurethane acrylate resin is obtained by reacting hexamethylene diisocyanate-based polyisocyanate, polyethylene glycol, hydroxy acrylate, and monohydroxy fluorine-containing monomer.

4. The UV-moisture dual-curing conformal adhesive according to claim 3, characterized in that: The hexamethylene diisocyanate-based polyisocyanate is a hexamethylene diisocyanate trimer; Preferably, the hexamethylene diisocyanate-based polyisocyanate is selected from one of HT-90, HT-100, HB-100, HT-300 or HT-600 of Wanhua Chemical; Preferably, the polyethylene glycol is selected from one of DL1000, DL-400 of Bluestar Dongda and PCL205U, PCL205, PCL208 or PCL210 of Daicel; Preferably, the acrylate is selected from one or a combination of at least two of hydroxyethyl methacrylate, hydroxypropyl methacrylate or pentaerythritol triacrylate; Preferably, the monohydroxy fluorine-containing monomer is selected from at least one of perfluorobutanol, perfluorobutylethanol, perfluorohexylethyl alcohol and 2-perfluorooctylethanol.

5. The UV-moisture dual-curing conformal adhesive according to claim 3, characterized in that: The reaction is carried out in the presence of a catalyst; Preferably, the catalyst is dibutyltin dilaurate; Preferably, the reaction is carried out in the presence of a polymerization inhibitor; Preferably, the polymerization inhibitor is selected from one or a combination of at least two of hydroquinone, p-hydroxyanisole, p-benzoquinone and naphthoquinone; Preferably, the reaction is carried out in the presence of an antioxidant; Preferably, the antioxidant is selected from one or a combination of at least two of 1076, BHT (2,6-di-tert-butyl-4-methylphenol) or TPP (triphenyl phosphite).

6. The UV-moisture dual-curing conformal adhesive according to claim 3, characterized in that: The molar ratio of the hexamethylene diisocyanate-based polyisocyanate to the polyethylene glycol is (1-1.2): (0.4-0.6); Preferably, the molar ratio of the hexamethylene diisocyanate-based polyisocyanate to the hydroxy acrylate is (1-1.2): (0.8-1); Preferably, the molar ratio of the hexamethylene diisocyanate-based polyisocyanate to the monohydroxy fluorine-containing monomer is (1-1.2): (0.4-0.6).

7. The UV-moisture dual-curing conformal adhesive according to any one of claims 3 to 6, characterized in that: The reaction specifically comprises the following steps: (1) mixing hexamethylene diisocyanate-based polyisocyanate and polyethylene glycol, as well as a polymerization inhibitor and an antioxidant, reacting, adding a catalyst, and continuing the reaction; (2) adding hydroxy acrylate and monohydroxy fluorine-containing monomer to the reaction solution obtained in step (1), reacting to obtain the fluorine-containing polyurethane acrylate resin; Preferably, after the mixing in step (1), the temperature is raised to 65-70° C. for reaction for 1-1.5 h, then the temperature is raised to 75-80° C. for reaction for 2-3 h, and after the catalyst is added, the reaction is continued for 1.5-2 h; Preferably, the reaction temperature in step (2) is 75° C. and the reaction time is 1-2 h; Preferably, the reactions of step (1) and step (2) are carried out under nitrogen protection.

8. The UV-moisture dual-curing conformal adhesive according to claim 1, characterized in that: The active diluent is selected from one or a combination of at least two of isobornyl acrylate, isobornyl methacrylate or isooctyl acrylate; Preferably, the photoinitiator is selected from one or a combination of at least two of initiators 651, 184, 1173, 500, 907, TPO or LTM; Preferably, the polymerization inhibitor in the formula of the UV-moisture dual-curing conformal adhesive is selected from one or a combination of at least two of hydroquinone, p-hydroxyanisole, p-benzoquinone or naphthoquinone; Preferably, the dehydrating agent is p-toluenesulfonyl isocyanate.

9. The method for preparing the UV-moisture dual-curing conformal adhesive according to any one of claims 1 to 8, characterized in that: The preparation method comprises the following steps: The active diluent and the photoinitiator are mixed, and then the fluorine-containing polyurethane acrylate resin, the polymerization inhibitor, and the dehydrating agent are added to the mixture, and mixed to obtain the UV-moisture dual-curing three-proof adhesive; Preferably, the mixing is carried out at 20-30°C; Preferably, the mixing is carried out under stirring; Preferably, the mixing is carried out under nitrogen protection; Preferably, the time for mixing the reactive diluent and the photoinitiator is 0.5 to 1 h; Preferably, the fluorine-containing polyurethane acrylate resin, polymerization inhibitor and dehydrating agent are added to the mixture and mixed for 0.5 to 1 hour.

10. Use of the UV-moisture dual-curing conformal adhesive according to any one of claims 1 to 8 in bonding electronic circuit boards.

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