Urethane acrylate, ultraviolet curing sealant and preparation method

Abstract

The invention provides polyurethane acrylate, an ultraviolet curing sealant and a preparation method thereof, the structural general formula of the polyurethane acrylate resin is A-D-(P2-D) n-P2-D-P1-D-[P2-(D-P2) n-D] m-A, D is a diisocyanate monomer; p1 is a polycarbonate polyol compound and has a molecular weight of 200 to 10000; p2 is a polybutadiene polyol compound and has a molecular weight of 200 to 10000; n is a natural number from 0 to 100; m is a natural number from 0 to 100; a is a hydroxyl acrylate monomer. According to the ultraviolet curing adhesive disclosed by the invention, polybutadiene and polycarbonate block polyurethane acrylate resin are taken as main components, the components have low moisture permeability, and are matched with other components in a specific ratio, so that the curing adhesive can effectively prevent moisture from invading and protect a sealed object from being affected with damp, and meanwhile, the ultraviolet curing adhesive also has relatively good chemical resistance, and can be used for sealing the sealed object. Comprising acid-sweat-resistant liquid, alkali-sweat-resistant liquid and grease.

Description

Technical Field

[0001] The invention relates to the technical field of curing adhesive preparation, and in particular to polyurethane acrylate, ultraviolet light curing sealant and a preparation method thereof. Background Art

[0002] The design and manufacturing of consumer electronic products such as smartphones and wearable devices are increasingly pursuing lightness, thinness and beauty, which has gradually eliminated the screws, buckles and other parts originally used to fix components. Instead, they are replaced by electronic adhesives that can meet the requirements of various screens, high appearance and thin body. In order to achieve full-screen borderless, no gaps in the screen and flat and thin appearance, many manufacturers will use a large amount of electronic adhesives for component bonding, fixing and sealing during the assembly process.

[0003] As an auxiliary material, electronic adhesives have become an indispensable raw material in the production of various products. Smartphones and wearable devices are important application areas of the adhesive industry. In order to meet the increasing requirements for the reliability of screen assembly of consumer electronic products, screen sealants not only need excellent bonding strength and drop resistance, but also need to have an extremely low water vapor permeability coefficient because the luminous part of the screen is very sensitive to moisture, to ensure water resistance at room temperature and in high temperature and high humidity environments. As the screen of a wearable electronic device, it is necessary to ensure the service life in high temperature environments in summer and oily environments, which increases the requirements for the product's acid, alkali, sweat, and oil and ester resistance.

[0004] The electronic paper screen sealant in the prior art solves the disadvantages of the existing electronic paper screen sealant that free radical polymerization occurs under the action of light, heat, etc. during storage and the storage stability is poor. However, the urethane acrylic polysiloxane resin contains polysiloxane monomers, and the siloxane monomers increase the water vapor transmission coefficient due to the flexibility of the silicon oxygen bond, and due to the low-grade characteristics of siloxane, the adhesion will decrease to a certain extent.

[0005] Japanese patent JP2020002222A light-curing sealant discloses a screen sealant composed of bisphenol A diacrylate resin and multifunctional acrylate monomers, which has the characteristics of fast curing speed, good heat resistance, low water vapor transmission rate, and good aging performance such as acid, alkali, sweat, oil and ester resistance. However, due to the poor toughness of epoxy acrylic resin, the sealant has low bonding strength and poor drop resistance.

[0006] Currently, polybutadiene acrylic resin is only unmodified, which has the advantage of low water vapor transmission rate, but weak bulk strength and bonding strength, poor surface dryness, poor miscibility, and slow reaction speed. Therefore, a new sealant is needed. Summary of the invention

[0007] The purpose of the present invention is to solve the problems of low adhesive strength and high water vapor permeability of the sealant of the wearable screen device in the prior art.

[0008] In the first aspect, the present invention provides a polybutadiene and polycarbonate block polyurethane acrylate, the general structural formula of which is:

[0009] AD-(P2-D)n-P2-D-P1-D-[P2-(D-P2)nD]mA, where:

[0010] D is a diisocyanate monomer;

[0011] P1 is a polycarbonate polyol compound having a molecular weight of 200-10000;

[0012] P2 is a polybutadiene polyol compound having a molecular weight of 200-10000;

[0013] n is a natural number from 0 to 100;

[0014] m is a natural number from 0 to 100;

[0015] A is a hydroxy acrylate monomer.

[0016] Further, the diisocyanate monomer includes one or more of toluene diisocyanate, diphenylmethane diisocyanate, dicyclohexylmethane diisocyanate, xylylene diisocyanate, 2,2,4-trimethylhexane diisocyanate, isophorone diisocyanate and hexamethyl diisocyanate.

[0017] Furthermore, the polybutadiene polyol compound includes one or more of (hydrogenated) polybutadiene-1,1-diol, (hydrogenated) polybutadiene-1,1-diol, (hydrogenated) polybutadiene-1,1-diol and tetrabutadiene copolymer polyol, and the molecular weight of the polyol in the polybutadiene polyol compound is 500-5000.

[0018] Furthermore, the polycarbonate polyol compound includes one or more polycarbonate diols obtained by transesterification of diphenyl carbonate with 1,6-hexanediol, 1,5-pentanediol, 1,6-hexanediol with 1,5-pentanediol, cyclohexanedimethanol, etc., and the molecular weight of the polyol in the polycarbonate polyol compound is 500-5000.

[0019] Furthermore, the hydroxy acrylate monomer is one or more of hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, trimethylolpropane diallyl ether, and caprolactone acrylate.

[0020] In a second aspect, the present invention provides a method for preparing polybutadiene and polycarbonate block polyurethane acrylate, comprising:

[0021] Under nitrogen conditions, polybutadiene diol, diisocyanate and a polymerization inhibitor are mixed and reacted, and then a catalyst is added to obtain a prepolymer 1 with isocyanate groups at both ends after the reaction;

[0022] Adding polycarbonate polyol to the prepolymer 1 to obtain a prepolymer 2 terminated with a single-end isocyanate group after reaction;

[0023] A hydroxy acrylate end-capping agent is added to the prepolymer 2, and after reaction, the polyurethane acrylate of the polybutadiene and polycarbonate polyol blocks is obtained.

[0024] Further, the reaction is carried out at 30°C-90°C for 0.5-1h before adding the catalyst, and at 40°C-100°C for 1-5h after adding the catalyst;

[0025] After adding polycarbonate polyol, react at 40°C-100°C for 1-5h;

[0026] After adding the hydroxy acrylate end-capping agent, react at 40°C-100°C for 1-5 hours.

[0027] Furthermore, the molar ratio of the diol to the diisocyanate and the hydroxy acrylate end-capping agent is n:n+1:2, wherein n is a natural number of 2-100; the diol includes polybutadiene diol and polycarbonate polyol.

[0028] Furthermore, the catalyst is an organotin catalyst, and the addition amount of the organotin catalyst is 10-10000 ppm.

[0029] In a third aspect, the present invention further provides a UV-curable sealant, comprising, by weight:

[0030] 20-40 parts of polybutadiene and polycarbonate block polyurethane acrylate;

[0031] Soft monomer 0-40 parts;

[0032] 10-40 parts of hard monomer;

[0033] 1-5 parts of coupling agent;

[0034] 1-5 parts of free radical photoinitiator;

[0035] 1-5 parts of hydrophobic fumed silica.

[0036] Furthermore, it also includes polybutadiene polyurethane acrylate and / or polycarbonate polyurethane acrylate, and the weight proportion of the polybutadiene polyurethane acrylate and / or polycarbonate polyurethane acrylate is less than the weight proportion of the polybutadiene and polycarbonate block polyurethane acrylate.

[0037] Furthermore, the polybutadiene polyurethane acrylate adopts one or more of the molecular weights in the range of 1000-50000 cps; the polycarbonate polyurethane acrylate adopts one or more of the molecular weights in the range of 1000-50000 cps.

[0038] Furthermore, the soft monomer includes one or more of 2-ethylhexyl acrylate, tetrahydrofuran acrylate, isodecyl acrylate, and dodecyl (meth)acrylate.

[0039] Furthermore, the hard monomer includes one or more of N,N dimethacrylate, isobornyl acrylate, 1,6-hexanediol diacrylate, polyethylene glycol dimethacrylate, ethoxyethoxyethyl acrylate, triethoxytrimethylolpropane triacrylate, trimethylolpropane triacrylate, nonaethoxytrimethylolpropane triacrylate, tripropylene glycol diacrylate, dipropylene glycol diacrylate, propoxylated neopentyl glycol diacrylate and pentaethoxypentaerythritol tetraacrylate.

[0040] In a fourth aspect, the present invention further provides a method for preparing a UV-curable sealant, comprising the following steps:

[0041] Mixing and stirring polybutadiene and polycarbonate-blocked polyurethane acrylate, soft monomer, hard monomer, coupling agent and photoinitiator to obtain a first mixture;

[0042] The hydrophobic fumed silica is added to the first mixture and stirred to obtain the UV-curable sealant.

[0043] Compared with the prior art, the present invention includes at least the following beneficial effects: the UV curing adhesive of the present invention uses polybutadiene and polycarbonate-blocked polyurethane acrylate as the main components, which have low water vapor permeability. When combined with other components in a specific ratio, the curing adhesive can effectively prevent moisture intrusion and protect the sealed object from moisture, while also having good resistance to wet and hot aging. By rationally designing the ratio and preparation process of each component, the UV curing adhesive of the present invention not only has good processing performance, but also the resin significantly improves the elongation at break and bonding strength of the colloid, so that the sealant has better resistance when subjected to tensile and shear forces. At the same time, by adopting a specific stirring process, the components can be fully mixed and evenly mixed, further improving the stability of product performance. DETAILED DESCRIPTION

[0044] The present invention will be described in more detail below, wherein preferred embodiments of the present invention are shown, and it should be understood that those skilled in the art can modify the present invention described herein, and still achieve the beneficial effects of the present invention. Therefore, the following description should be understood as being widely known to those skilled in the art, and not as a limitation of the present invention.

[0045] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0046] The present invention is described in more detail by way of example in the following paragraphs. As described below, the advantages and features of the present invention will become more apparent.

[0047] In the first aspect, the present embodiment provides a polybutadiene and polycarbonate block polyurethane acrylate, the general structural formula of which is:

[0048] AD-(P2-D)n-P2-D-P1-D-[P2-(D-P2)nD]mA, where:

[0049] D is a diisocyanate monomer;

[0050] P1 is a polycarbonate polyol compound having a molecular weight of 200-10000;

[0051] P2 is a polybutadiene polyol compound having a molecular weight of 200-10000;

[0052] n is a natural number from 0 to 100;

[0053] m is a natural number from 0 to 100;

[0054] A is a hydroxy acrylate monomer.

[0055] Further, the diisocyanate monomer includes one or more of toluene diisocyanate, diphenylmethane diisocyanate, dicyclohexylmethane diisocyanate, xylylene diisocyanate, 2,2,4-trimethylhexane diisocyanate, isophorone diisocyanate and hexamethyl diisocyanate.

[0056] Preferably, the diisocyanate monomer is selected from diphenylmethane diisocyanate, dicyclohexylmethane diisocyanate, and isophorone diisocyanate.

[0057] Furthermore, the polybutadiene polyol compound includes one or more of (hydrogenated) polybutadiene-1,2-diol, (hydrogenated) polybutadiene-1,4-tetrabutadiene polyol, (hydrogenated) polybutadiene-1,2-diol and polybutadiene-1,4-tetrabutadiene copolymer polyol, and the molecular weight of the polyol in the polybutadiene polyol compound is 500-5000.

[0058] Preferably, the polybutadiene polyol compound is (hydrogenated) polybutadiene polyol.

[0059] Furthermore, the polycarbonate polyol compound includes one or more polycarbonate diols obtained by transesterification of diphenyl carbonate with 1,6-hexanediol, 1,5-pentanediol, 1,6-hexanediol with 1,5-pentanediol, cyclohexanedimethanol, etc., and the molecular weight of the polyol in the polycarbonate polyol compound is 500-5000.

[0060] Preferably, the polycarbonate polyol compound is a polycarbonate diol obtained by ester exchange of diphenyl carbonate with 1,6-hexanediol and 1,5-pentanediol.

[0061] Furthermore, the hydroxy acrylate monomer includes one or more of hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, trimethylolpropane diallyl ether, and caprolactone acrylate.

[0062] Preferably, the hydroxy acrylate monomer is hydroxyethyl acrylate.

[0063] Specifically, the polyurethane acrylate resin of polybutadiene and polycarbonate blocks has a viscosity of 5000-50000 cps at 25°C.

[0064] In a second aspect, this embodiment also provides a method for preparing the polyurethane acrylate of polybutadiene and polycarbonate blocks, comprising:

[0065] Under nitrogen conditions, polybutadiene diol, diisocyanate and a polymerization inhibitor are mixed and reacted, and then a catalyst is added to obtain a prepolymer 1 with isocyanate groups at both ends after the reaction;

[0066] Adding polycarbonate polyol to the prepolymer 1 to obtain a prepolymer 2 terminated with a single-end isocyanate group after reaction;

[0067] A hydroxy acrylate end-capping agent is added to the prepolymer 2, and after reaction, the polyurethane acrylate of the polybutadiene and polycarbonate polyol blocks is obtained.

[0068] Further, the reaction is carried out at 30°C-90°C for 0.5-1h before adding the catalyst, and at 40°C-100°C for 1-5h after adding the catalyst;

[0069] After adding polycarbonate polyol, react at 40°C-100°C for 1-5h;

[0070] After adding the hydroxy acrylate end-capping agent, react at 40°C-100°C for 1-5 hours.

[0071] Furthermore, the molar ratio of the diol to the diisocyanate and the hydroxy acrylate end-capping agent is n:n+1:2, wherein n is a natural number of 2-100; the diol includes polybutadiene diol and polycarbonate polyol.

[0072] Furthermore, the catalyst is an organotin catalyst, and the addition amount of the organotin catalyst is 10-10000 ppm.

[0073] In a third aspect, the present invention further provides a UV-curable sealant, comprising:

[0074] 20-40 parts of polybutadiene and polycarbonate block polyurethane acrylate;

[0075] Soft monomer 0-40 parts;

[0076] 10-40 parts of hard monomer;

[0077] 1-5 parts of coupling agent;

[0078] 1-5 parts of free radical photoinitiator;

[0079] 1-5 parts of hydrophobic fumed silica.

[0080] Wherein, the polybutadiene and polycarbonate block polyurethane acrylate resins are obtained by the above-mentioned preparation method.

[0081] Furthermore, it also includes polybutadiene polyurethane acrylate resin and / or polycarbonate polyurethane acrylate resin, and the weight proportion of the polybutadiene polyurethane acrylate resin and / or polycarbonate polyurethane acrylate resin is less than the weight proportion of the polybutadiene and polycarbonate block polyurethane acrylate resin.

[0082] Specifically, when the above two resins are added to the curing adhesive, the weight fraction or the sum of the weight fractions of the resins does not exceed 50% of the weight fraction of the polybutadiene and polycarbonate block polyurethane acrylate resins.

[0083] Furthermore, the polybutadiene polyurethane acrylate resin adopts one or more of the polybutadiene polyurethane acrylate resins having a molecular weight of 1000-50000 cps.

[0084] In a preferred embodiment, the polybutadiene polyurethane acrylic resin can be one or more of CN310NS, CN307NS, CN308NS of Sartomer, FSP8004 of Runao Chemical, etc.

[0085] The polycarbonate polyurethane acrylate resin adopts one or more of the polycarbonate polyurethane acrylate resins with a molecular weight of 1000-50000 cps.

[0086] In a preferred embodiment, the polycarbonate polyurethane acrylic resin can be one or more of Sartomer CN9001ns, CN9002NS, FSP8674 of Runao Chemical, etc.

[0087] Furthermore, the soft monomer includes one or more of 2-ethylhexyl acrylate, tetrahydrofuran acrylate, isodecyl acrylate, and dodecyl (meth)acrylate.

[0088] Preferably, the soft monomer is 2-ethylhexyl acrylate or dodecyl acrylate.

[0089] Furthermore, the hard monomer is one or more of isobornyl acrylate, 1,6-hexanediol diacrylate, polyethylene glycol dimethacrylate, ethoxyethoxyethyl acrylate, triethoxytrimethylolpropane triacrylate, trimethylolpropane triacrylate, nonaethoxytrimethylolpropane triacrylate, tripropylene glycol diacrylate, dipropylene glycol diacrylate, propoxylated neopentyl glycol diacrylate and pentaethoxypentaerythritol tetraacrylate.

[0090] Preferably, the hard monomer is selected from isobornyl acrylate and dipropylene glycol diacrylate.

[0091] In a fourth aspect, the present invention further provides a method for preparing the above-mentioned UV-curable sealant, comprising the following steps:

[0092] Mixing and stirring polybutadiene and polycarbonate-blocked polyurethane acrylate, soft monomer, hard monomer, coupling agent and photoinitiator to obtain a first mixture;

[0093] The hydrophobic fumed silica is added to the first mixture and stirred to obtain the UV-curable sealant.

[0094] Specifically, the speed of the first mixing and stirring is 800r / min~1200r / min, and the time of the first mixing and stirring is 30 minutes~40 minutes; the speed of the second mixing and stirring is 200r / min~300r / min, and the time of the second mixing and stirring is 10 minutes~15 minutes.

[0095] The stirring process is carried out under vacuum, and the vacuum degree of the preset vacuum environment is -0.03MPa--0.08MPa, for example -0.05MPa or -0.07MPa.

[0096] Embodiment 1

[0097] The specific steps for preparing polyurethane acrylate of polybutadiene and polycarbonate polyol blocks are as follows:

[0098] Step 1): under nitrogen conditions, polybutadiene diol, diisocyanate and polymerization inhibitor were added to a four-necked flask, reacted at 50° C. for 30 minutes, an organic tin catalyst xxppm was added, and reacted at 60° C. for 1 hour to obtain a prepolymer 1 terminated with isocyanate groups at both ends.

[0099] Step 2): Add polycarbonate polyol and react at 60° C. for 1 hour to obtain a single-end isocyanate-terminated prepolymer II.

[0100] Step 3): Add a hydroxy acrylate end-capping agent and react at 60° C. for 1 hour to obtain a polyurethane acrylate resin having polybutadiene and polycarbonate blocks.

[0101] Embodiment 2

[0102] Weigh the following raw materials by weight:

[0103] Table 1

[0104]

[0105]

[0106] The specific preparation steps are as follows:

[0107] S1: providing a self-made block resin, a soft monomer, a hard monomer and a photoinitiator by weight for a first mixing and stirring at a speed of 1000 r / min for 30 min to obtain a first mixture;

[0108] S2: adding hydrophobic fumed silica to the first mixture and mixing and stirring at a speed of 250 r / min for 12 min to obtain a UV-curable sealant.

[0109] The above steps are carried out in a vacuum environment with a vacuum degree of -0.06 MPa. In this embodiment, the self-made block PUA is the polyurethane acrylate resin with polybutadiene and polycarbonate blocks prepared in the first embodiment.

[0110] According to the data of Example 1 to Example 5 in Table 1 above and the above preparation method, several different UV-curable sealants were obtained, and the performance of the obtained sealants was tested and compared with Comparative Examples 1 to Comparative Examples 3.

[0111] The main resin used in Example 1 is a polyurethane acrylate resin with polybutadiene and polycarbonate blocks, and a polybutadiene polyurethane acrylate resin is added; the main resin used in Example 2 is a polyurethane acrylate resin with polybutadiene and polycarbonate blocks, and a polycarbonate polyurethane acrylate resin is added; the resin used in Example 3 is the same as that in Example 2, but the ratio of the two resins added is different from that in Example 2;

[0112] In Example 4 and Example 5, only butadiene and polycarbonate block polyurethane acrylate resin are added, but the addition of hard monomers is different.

[0113] The main resin used in Comparative Example 1 is polybutadiene polyurethane acrylate, the main resin used in Comparative Example 2 is polycarbonate polyurethane acrylate, and the main resin used in Comparative Example 3 is polybutadiene polyurethane acrylate and polycarbonate polyurethane acrylate is used as an auxiliary.

[0114] Performance testing includes the following steps:

[0115] 1) Thrust test

[0116] Test substrate: tempered glass (100*25*5mm), patch glass (4*4*1mm)

[0117] Sample preparation: Use a film scraper to scrape a 100um thick glue layer, place the patch glass in the glue layer, press lightly with tweezers, take out the patch glass, place it on the tempered glass sheet, and press lightly with tweezers. The sample preparation is completed and put it into a UV light box for curing.

[0118] Curing conditions: UV LED light source with a wavelength of 365nm, 1000mw / cm2 of energy for 5s, and room temperature curing for 24 hours

[0119] Test conditions: thrust machine, push height 200um, push speed 100mm / min (to be determined)

[0120] 2) Water vapor transmission rate test

[0121] Sample preparation: Use a 300um return height limit frame to limit the height and solidify a 100*100*0.3mm sample block.

[0122] 3) Curing conditions are the same as thrust test

[0123] Test conditions: 55°C, 55% humidity, test for 3 days, and obtain the water vapor permeability and water vapor permeability coefficient of 300um rubber block.

[0124] 4) Body strength and elongation at break test

[0125] Sample preparation: Use a 1mm return height limit frame to limit the height, solidify the 150*150*1mm sample block, and use an I-type mold to cut out bone rod-shaped splines.

[0126] 5) Curing conditions are the same as thrust test

[0127] Test conditions: Use a universal tensile testing machine to break the specimen at a speed of 500mm / min to obtain the bulk strength and elongation at break of the rubber sample.

[0128] 6) Chemical resistance test

[0129] Table 2

[0130]

[0131] 0.5 ml of the corresponding acid sweat, alkaline sweat and oil ester were dripped onto each thrust sample, and the sample was wrapped with non-woven fabric and sealed with PP plastic bag, and the sample was placed in a high temperature and high humidity aging box at 65℃ and 95% humidity for 72 hours. After cooling to room temperature, thrust test was performed.

[0132] The results obtained by the above performance test are shown in Table 3 below. It can be seen from the test results in the table that the proportion of polycarbonate polyurethane acrylate in Example 3 reaches 20%, and the chemical resistance reaches the best, but the water vapor permeability has reached the upper limit, and the polycarbonate polyol also has a very low water absorption rate and resistance to wet and hot aging. The self-made polybutadiene and polycarbonate polyol block polyurethane acrylic resin retains the low water vapor permeability and wet and hot aging resistance of the low-polarity polybutadiene polyurethane acrylic resin, while improving the elongation at break and the bonding strength of the colloid, and most importantly, solves the problem that the traditional UV curing sealant is not resistant to acid, alkali, sweat and oil. At the same time, it can be seen from the excellent formula compatibility of Examples 1, 2 and 3 that the formula allocation space is also greatly improved, and a variety of glues with different properties required by customers can be prepared. Comparative Example 1 shows that the bonding strength of the traditional UV sealant is relatively small, and it shows a significant attenuation in the three chemical resistance tests. Comparative Example 2 shows that the polycarbonate polyurethane acrylic resin has high bonding strength and excellent chemical resistance, but the water vapor transmission rate is greater than 20g / m2.24h, which does not meet the screen sealing requirements. Comparative Example 3 shows that due to the large difference in polarity between the two polyurethane acrylic resins, the simple mixing compatibility is poor and a long-term stable sealant formula cannot be output.

[0133] Table 3

[0134]

[0135] The above specific examples are used to illustrate the present invention, which is only used to help understand the present invention and is not intended to limit the present invention. For those skilled in the art, according to the concept of the present invention, some simple deductions, modifications or substitutions can be made.

Claims

1. A polyurethane acrylate of polybutadiene and polycarbonate blocks, characterized in that: Its general structural formula is: AD-(P2-D)n-P2-D-P1-D-[P2-(D-P2)nD]mA, where: D is a diisocyanate monomer; P1 is a polycarbonate polyol compound having a molecular weight of 200-10000; P2 is a polybutadiene polyol compound having a molecular weight of 200-10000; n is a natural number from 0 to 100; m is a natural number from 0 to 100; A is a hydroxy acrylate monomer.

2. The polyurethane acrylate of polybutadiene and polycarbonate blocks according to claim 1, characterized in that: The diisocyanate monomer includes one or more of toluene diisocyanate, diphenylmethane diisocyanate, dicyclohexylmethane diisocyanate, xylylene diisocyanate, 2,2,4-trimethylhexane diisocyanate, isophorone diisocyanate and hexamethyl diisocyanate.

3. The polyurethane acrylate of polybutadiene and polycarbonate blocks according to claim 1, characterized in that: The polybutadiene polyol compound includes one or more of (hydrogenated) polybutadiene-1,1-diol, (hydrogenated) polybutadiene-1,1-diol, (hydrogenated) polybutadiene-1,1-diol and tetrabutadiene copolymer polyol, and the molecular weight of the polyol in the polybutadiene polyol compound is 500-5000.

4. The polyurethane acrylate of polybutadiene and polycarbonate blocks according to claim 1, characterized in that: The polycarbonate polyol compound includes one or more polycarbonate diols obtained by transesterification of diphenyl carbonate with 1,6-hexanediol, 1,5-pentanediol, 1,6-hexanediol with 1,5-pentanediol, cyclohexanedimethanol, etc. The molecular weight of the polyol in the polycarbonate polyol compound is 500-5000.

5. The polyurethane acrylate of polybutadiene and polycarbonate blocks according to claim 1, characterized in that: The hydroxy acrylate monomer is one or more of hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, trimethylolpropane diallyl ether, and caprolactone acrylate.

6. A method for preparing polyurethane acrylate of polybutadiene and polycarbonate blocks, comprising: Under nitrogen conditions, polybutadiene diol, diisocyanate and a polymerization inhibitor are mixed and reacted, and then a catalyst is added to obtain a prepolymer 1 with isocyanate groups at both ends after the reaction; Adding polycarbonate polyol to the prepolymer 1 to obtain a prepolymer 2 terminated with a single-end isocyanate group after reaction; A hydroxy acrylate end-capping agent is added to the prepolymer 2, and after reaction, the polyurethane acrylate of the polybutadiene and polycarbonate polyol blocks is obtained.

7. The method for preparing polyurethane acrylate of polybutadiene and polycarbonate blocks according to claim 6, characterized in that: Before adding the catalyst, the reaction is carried out at 30°C-90°C for 0.5-1h, and after adding the catalyst, the reaction is carried out at 40°C-100°C for 1-5h; After adding polycarbonate polyol, react at 40°C-100°C for 1-5h; After adding the hydroxy acrylate end-capping agent, the reaction is carried out at 40°C-100°C for 1-5 hours.

8. The method for preparing polyurethane acrylate of polybutadiene and polycarbonate blocks according to claim 6, characterized in that: The molar ratio of the diol to the diisocyanate and the hydroxy acrylate end-capping agent is n:n+1:2, wherein n is a natural number of 2-100; the diol includes polybutadiene diol and polycarbonate polyol.

9. The method for preparing polyurethane acrylate of polybutadiene and polycarbonate blocks according to claim 6, characterized in that: The catalyst is an organotin catalyst, and the addition amount of the organotin catalyst is 10-10000ppm.

10. A UV-curable sealant, characterized in that: By weight, including: 20-40 parts of polybutadiene and polycarbonate block polyurethane acrylate; Soft monomer 0-40 parts; 10-40 parts of hard monomer; 1-5 parts of coupling agent; 1-5 parts of free radical photoinitiator; 1-5 parts of hydrophobic fumed silica.

11. The UV-curable sealant according to claim 10, characterized in that: It also includes polybutadiene polyurethane acrylate and / or polycarbonate polyurethane acrylate, and the weight proportion of the polybutadiene polyurethane acrylate and / or polycarbonate polyurethane acrylate is less than the weight proportion of the polybutadiene and polycarbonate block polyurethane acrylate.

12. The UV-curable sealant according to claim 11, characterized in that: The polybutadiene polyurethane acrylate adopts one or more of the molecular weights in the range of 1000-50000cps; the polycarbonate polyurethane acrylate adopts one or more of the molecular weights in the range of 1000-50000cps.

13. The UV-curable sealant according to claim 10, characterized in that: The soft monomer includes one or more of 2-ethylhexyl acrylate, tetrahydrofuran acrylate, isodecyl acrylate, and dodecyl (meth)acrylate.

14. The UV-curable sealant according to claim 10, characterized in that: The hard monomers include one or more of N,N dimethacrylate, isobornyl acrylate, 1,6-hexanediol diacrylate, polyethylene glycol dimethacrylate, ethoxyethoxyethyl acrylate, triethoxytrimethylolpropane triacrylate, trimethylolpropane triacrylate, nonaethoxytrimethylolpropane triacrylate, tripropylene glycol diacrylate, dipropylene glycol diacrylate, propoxylated neopentyl glycol diacrylate and pentaethoxypentaerythritol tetraacrylate.

15. A method for preparing a UV-curable sealant, characterized in that: The following steps are involved: Mixing and stirring polybutadiene and polycarbonate-blocked polyurethane acrylate, soft monomer, hard monomer, coupling agent and photoinitiator to obtain a first mixture; The hydrophobic fumed silica is added to the first mixture and stirred to obtain the UV-curable sealant.

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