A boron-containing oligomer for an anti-aging high-transparency addition-type silicone rubber, and a preparation method and application thereof

Abstract

The application discloses a boron-containing oligomer for anti-aging high-transparency addition type silicone rubber and a preparation method and application thereof. The boron-containing oligomer is an unsaturated bond-containing boron-containing oligomer; the unsaturated bond is at least one selected from a carbon-carbon double bond, a carbon-carbon triple bond and a large Pi bond; and the boron-containing oligomer comprises at least one boron-oxygen-silicon bond. The prepared boron-containing oligomer is used as an adhesion promoter in addition type silicone rubber, can greatly improve the bonding performance of the addition type silicone rubber to metal and plastic substrates under the premise of ensuring high transparency without using a traditional primer, and thus greatly promotes the application range of the addition type silicone rubber bonding sealant.

Description

Technical Field

[0001] This invention belongs to the field of silicone rubber bonding and sealing materials and their preparation, specifically relating to a boron-containing oligomer for aging-resistant, highly transparent addition-curing silicone rubber, its preparation method, and its application. Background Technology

[0002] Addition-cure silicone rubber is produced by the hydrosilylation of vinyl-containing polysiloxanes and polysiloxanes containing multiple silane-hydrogen bonds in the presence of a platinum catalyst. This type of silicone rubber is widely used due to its excellent properties, such as no byproducts generated during vulcanization and relatively low vulcanization temperature and short vulcanization time. However, addition-cure silicone rubber has poor adhesion to substrates, requiring extensive use of primers to treat the substrate surface during application. This drawback increases both cost and workload. Therefore, researching efficient tackifiers to enhance the bulk adhesion of addition-cure silicone rubber plays a crucial role in its development.

[0003] Previous research has also reported on addition-type silicone rubber adhesives in numerous patent works. Chinese patent CN202210664176.1 reports a two-component tackifier, preparing a polysiloxane containing epoxy and amino groups. Chinese patent CN202110272736.4 prepares silanes or siloxanes containing acrylic groups. The tackifiers mentioned in these patents have some effect on improving the adhesion between metals and plastics, but the effect is not significant.

[0004] In our previous work, we synthesized a borate ester tackifier for addition-cure silicone rubber using Chinese patent CN201410748954.0, and a boron-containing small-molecule tackifier for addition-cure silicone rubber using Chinese patent CN201410725194.1. Both tackifiers can significantly improve the bonding strength to metal sheets and the shear strength on PET films. However, the transparency of addition-cure silicone rubber is affected after adding these two tackifiers, and their preparation processes are complex and costly, which is not conducive to widespread application. Summary of the Invention

[0005] The technical problem to be solved by this invention is how to improve the adhesion performance of addition-cured silicone rubber to metal and plastic substrates while maintaining high transparency and good aging resistance.

[0006] To solve the above-mentioned technical problems, the present invention provides the following technical solution:

[0007] A boron-containing oligomer, wherein the boron-containing oligomer is a boron-containing oligomer containing unsaturated bonds; the unsaturated bonds are selected from at least one of carbon-carbon double bonds, carbon-carbon triple bonds, and large π bonds; the boron-containing oligomer includes at least one boron-oxy-silicon bond, for example, two boron-oxy-silicon bonds, three boron-oxy-silicon bonds, or five boron-oxy-silicon bonds.

[0008] According to an embodiment of the present invention, the raw materials for the boron-containing oligomer include: small molecule alkoxysilanes containing unsaturated bonds and compounds containing active boron hydroxyl groups.

[0009] According to an embodiment of the present invention, the boron-containing oligomer is obtained by condensation reaction of a small molecule alkoxysilane containing unsaturated bonds with a compound containing active boron hydroxyl groups.

[0010] According to an embodiment of the present invention, the small molecule alkoxysilane containing unsaturated bonds is selected from at least one of the following: γ-glycidoxypropyltrimethoxysilane, γ-(methacryloyloxy)propyltrimethoxysilane, γ-aminopropyltriethoxysilane, allyltrimethoxysilane, triethoxyphenylsilane, triethoxyvinylsilane, 3-glycidoxypropyltriethoxysilane, trimethoxyphenylsilane, tri(2-methoxyethoxy)vinylsilane, vinyltrimethoxysilane, trimethoxy(2-phenylethyl)silane, (3-glycidoxypropyl)trimethoxysilane, diethoxy(methyl)phenylsilane, diethoxydiphenylsilane, diethoxymethyl[(3-epoxyethylmethoxy)propyl]silane, diethoxy(methyl)vinylsilane.

[0011] According to embodiments of the present invention, the compound containing an active boron hydroxyl group is selected from at least one of the following: 4-nitrophenylboronic acid, 2-chlorophenylboronic acid, 3-chlorophenylboronic acid, isopropylboronic acid, 3-hydroxyphenylboronic acid, 4-iodophenylboronic acid, butylboronic acid, 4-vinylphenylboronic acid, 3-cyanophenylboronic acid, 3-hydroxymethylphenylboronic acid, phenylethylboronic acid, 3-furanboronic acid, 8-quinolineboronic acid, but-3-eneboronic acid, 2-thiopheneboronic acid, p-methylphenylboronic acid, cyclohexylboronic acid, 2-pyridineboronic acid, 4-ethylphenylboronic acid, and 1-phenylvinylboronic acid.

[0012] The present invention also provides a method for preparing the above-mentioned boron-containing oligomers, the method comprising: performing a condensation reaction between a small molecule alkoxysilane containing unsaturated bonds and a compound containing active boron hydroxyl groups to obtain the boron-containing oligomers.

[0013] According to an embodiment of the present invention, in the preparation method, the small molecule alkoxysilane containing unsaturated bonds and the compound containing active boron hydroxyl groups have the meanings described above.

[0014] According to an embodiment of the present invention, in the preparation method, the molar ratio of the small molecule alkoxysilane containing unsaturated bonds to the compound containing active boron hydroxyl groups is 1:0.3-3, for example, 1:0.33, 1:0.5, 1:0.83 or 1:1.

[0015] According to an embodiment of the present invention, a polycondensation catalyst is also added during the polycondensation reaction. Preferably, the polycondensation catalyst is selected from at least one of sulfonated resin, cation exchange resin, anion exchange resin, aluminosilicate, ZSM-5 zeolite, etc., and is preferably an anion exchange resin. Further, the anion exchange resin is selected from at least one of FPA53 anion exchange resin, 717 strong basic styrene-based anion exchange resin, D392 macroporous anion exchange resin, LX-TS4 macroporous strong basic anion exchange resin, IRA-411 anion exchange resin, D900 macroporous weak basic anion exchange resin, Q strong anion exchange resin Rigose Q, and DEAE weak anion exchange resin Rigose DEAE HiRes.

[0016] According to an embodiment of the present invention, the temperature of the condensation reaction is 30-100°C, for example, 60°C or 70°C.

[0017] According to an embodiment of the present invention, the pressure of the reaction system of the condensation reaction is maintained at 0.01 MPa-2 MPa, for example, 0.1 MPa.

[0018] According to an embodiment of the present invention, in order to promote the full progress of the condensation reaction, the preparation method further includes adding a solvent to the condensation reaction so that the entire reaction system is carried out in a solvent environment.

[0019] According to an embodiment of the present invention, in the preparation method, the solvent is selected from at least one of ethanol, methanol, toluene, ethyl acetate, tetrahydrofuran, acetone, acetonitrile, n-hexane, dichloromethane, isopropanol, xylene, and petroleum ether.

[0020] According to an embodiment of the present invention, in the preparation method, after adding the solvent, the mass fraction of the reactants in the reaction system is 5%-50%, for example, 10%. In the present invention, the reactants include small molecule alkoxysilanes containing unsaturated bonds and compounds containing active boron hydroxyl groups.

[0021] The present invention also provides the application of the above-mentioned boron-containing oligomers with unsaturated bonds in aging-resistant addition-type silicone rubber, preferably as a tackifier.

[0022] The present invention also provides an addition-cure silicone rubber composition comprising the following components: an addition-cure silicone rubber base, reinforcing filler, tackifier, and catalyst, wherein the tackifier comprises the aforementioned boron-containing oligomer.

[0023] According to an embodiment of the present invention, the reinforcing filler is selected from vinyl MQ silicone resin.

[0024] According to an embodiment of the present invention, the mass of the reinforcing filler is 30%-100% of the mass of the addition-type silicone rubber base, for example, 65%.

[0025] According to an embodiment of the invention, the tackifier is 0.5%-3% of the mass of the addition-type silicone rubber base, for example, 0.61%, 1.57%, 1.75% or 2.49%.

[0026] According to an embodiment of the present invention, the catalyst is selected from platinum catalysts.

[0027] According to an embodiment of the present invention, the mass of the platinum catalyst is 0.5‰-2‰ of the mass of the addition-type silicone rubber base, for example, 1‰.

[0028] According to an embodiment of the present invention, the addition-cure silicone rubber base adhesive comprises a mixture of terminal vinyl silicone oil and hydrogen-containing MQ silicone resin. Preferably, the hydrogen content of the hydrogen-containing MQ silicone resin is 0.1-1%, for example, 0.4%. Preferably, the viscosity of the terminal vinyl silicone oil is 50,000-200,000 mPa·s, for example, 100,000 mPa·s.

[0029] According to an embodiment of the present invention, in the addition-cure silicone rubber base adhesive, the mass ratio of the end vinyl silicone oil to the hydrogen-containing MQ silicone resin is 1-10:0.1-5, for example, 10:3.6.

[0030] The present invention also provides an adhesive sealant prepared by the above-described addition-curing silicone rubber composition.

[0031] Preferably, the adhesive sealant is prepared by a method comprising the following steps: uniformly mixing the boron-containing oligomer, addition-type silicone rubber base, reinforcing filler and platinum catalyst, and then performing a compounding process on the resulting mixture to obtain the adhesive sealant.

[0032] Beneficial effects:

[0033] This invention involves a condensation reaction between a small-molecule alkoxysilane containing unsaturated bonds and a compound containing active boron hydroxyl groups to obtain a boron-containing oligomer containing unsaturated bonds. The boron-containing oligomer prepared according to this invention, used as a tackifier in addition-cure silicone rubber, can significantly improve the adhesion of addition-cure silicone rubber to metal and plastic substrates without the use of traditional primers, while maintaining high transparency, thereby greatly expanding the application range of addition-cure silicone rubber adhesives and sealants. Furthermore, the preparation method of the boron-containing oligomer containing unsaturated bonds described in this invention is novel, efficient, low-cost, produces high-purity products, and has a simple operating process, making it suitable for industrial production. Attached Figure Description

[0034] Figure 1 This is the molecular structural formula of Example 1.

[0035] Figure 2 NMR of Example 1 29 Si spectrum.

[0036] Figure 3 This is the molecular structural formula of Example 3.

[0037] Figure 4 NMR of Example 3 29 Si spectrum.

[0038] Figure 5 The violet-visible absorption spectra of Comparative Examples 1, 2, 3, 4, 5, 5, and 7 are shown. Detailed Implementation

[0039] The technical solution of the present invention will be further described in detail below with reference to specific embodiments. It should be understood that the following embodiments are merely illustrative and explanatory of the present invention, and should not be construed as limiting the scope of protection of the present invention. All technologies implemented based on the above content of the present invention are covered within the scope of protection intended by the present invention.

[0040] Unless otherwise stated, the raw materials and reagents used in the following examples are commercially available products or can be prepared by known methods.

[0041] In the following examples, the shear strength test of the samples was performed in accordance with GB 7124-2008 Method for Determination of Tensile Shear Strength of Adhesives; the transparency test was performed in accordance with GB / T 2410-2008 Method for Determination of Light Transmittance and Haze of Transparent Plastics.

[0042] Example 1: Preparation of boron-containing oligomer 1

[0043] In a 500ml three-necked flask equipped with a serpentine condenser, 5.92g of p-vinylphenylboronic acid and 15.2g of vinyltriethoxysilane (the molar ratio of vinyltriethoxysilane to p-vinylphenylboronic acid was 1:0.5) were added, along with 0.2112g of A854519 (717) strong basic styrene-based anion exchange resin produced by McLean Company as a catalyst. The mixture was completely dissolved in 211.2g of anhydrous ethanol. After stirring at room temperature for 1 hour to mix evenly, the mixture was heated to 65°C and reacted for 6 hours. The anion exchange resin was removed by filtration, and most of the anhydrous ethanol was removed by rotary evaporation. The remaining anhydrous ethanol was removed by vacuum distillation. The reaction was stopped when no more bubbles appeared after about 1 hour, yielding boron-containing oligomer 1.

[0044] The structural formula of the boron-containing oligomer 1 synthesized in this embodiment is as follows: Figure 1 As shown, the synthesized boron-containing oligomer 1 contains one, two, and three boron-oxy-silicon bonds.

[0045] The NMR spectrum of boron-containing oligomer 1 synthesized in this embodiment is as follows: Figure 2 As shown, -57.16ppm and -59.02ppm are the NMR peaks and their splitting peaks of one boron-oxy-silicon bond in the oligomer; -65.98ppm and -67.53ppm are the NMR peaks and their splitting peaks of two boron-oxy-silicon bonds in the oligomer; and -74.06ppm and -75.29ppm are the NMR peaks and their splitting peaks of two boron-oxy-silicon bonds in the oligomer. The NMR results indicate that the boron-containing oligomer 1 obtained in this embodiment possesses… Figure 1 The structure shown.

[0046] Example 2: Preparation of boron-containing oligomer 2

[0047] In a 500ml three-necked flask equipped with a serpentine condenser, 5.92g of p-vinylphenylboronic acid and 22.8g of vinyltriethoxysilane (the molar ratio of vinyltriethoxysilane to p-vinylphenylboronic acid was 1:0.33) were added, along with 0.2872g of A854519 (717) strong basic styrene-based anion exchange resin produced by McLean Company as a catalyst. The mixture was completely dissolved in 287.2g of anhydrous ethanol. After stirring at room temperature for 1 hour to mix evenly, the mixture was heated to 65°C and reacted for 6 hours. The anion exchange resin was removed by filtration, and most of the anhydrous ethanol was removed by rotary evaporation. The remaining anhydrous ethanol was removed by vacuum distillation. The reaction was stopped when no more bubbles appeared after about 1 hour, yielding boron-containing oligomer 2.

[0048] Example 3: Preparation of boron-containing oligomer 3

[0049] In a 500ml three-necked flask equipped with a serpentine condenser, 14.8g of p-vinylphenylboronic acid and 16g of methylvinyldiethoxysilane (molar ratio of methylvinyldiethoxysilane to p-vinylphenylboronic acid was 1:1) were added. 0.308g of A854519 (717) strong basic styrene-based anion exchange resin (manufactured by McLean) was added as a catalyst and completely dissolved in 308g of anhydrous ethanol. After stirring at room temperature for 1 hour to mix thoroughly, the mixture was heated to 65°C and reacted for 6 hours. The anion exchange resin was removed by filtration. Most of the anhydrous ethanol was removed by rotary evaporation, and the remaining anhydrous ethanol was removed by vacuum distillation. The reaction was stopped after approximately 1 hour when no more bubbles appeared, yielding boron-containing oligomer 3. The structural formula of the synthesized oligomer is as follows: Figure 3 As shown, the synthesized oligomers contain one or two boron-oxysilicon bonds. The peak at -18.61 ppm is the peak of the starting material methyldiethoxyvinylsilane. The NMR spectrum of the synthesized oligomers is shown below. Figure 2As shown, -27.56ppm and -35.52ppm are the end-group peak and the silicon-oxygen backbone peak, respectively, confirming the successful synthesis of the above oligomers by NMR.

[0050] Example 4: Preparation of boron-containing oligomer 4

[0051] In a 500ml three-necked flask equipped with a serpentine condenser, 7.4g of p-vinylphenylboronic acid and 16g of methylvinyldiethoxysilane (the molar ratio of methylvinyldiethoxysilane to p-vinylphenylboronic acid was 1:0.5) were added. 0.234g of A854519 (717) strong basic styrene-based anion exchange resin produced by McLean was added as a catalyst. The mixture was completely dissolved in 234g of anhydrous ethanol. After stirring at room temperature for 1 hour to mix evenly, the mixture was heated to 65°C and reacted for 6 hours. The anion exchange resin was removed by filtration. Most of the anhydrous ethanol was removed by rotary evaporation of the reaction system, and the residual anhydrous ethanol was removed by vacuum distillation. The reaction was stopped when no more bubbles appeared after about 1 hour, yielding boron-containing oligomer 4.

[0052] Example 5

[0053] Preparation and performance determination of addition-type silicone rubber adhesive sealant 1:

[0054] The composition was obtained by mixing 0.17g of boron-containing oligomer 1 obtained in Example 1, 8.5g of vinyl-terminated silicone oil with a viscosity of 100000mPa.s, 3g of hydrogen-containing MQ silicone resin with a hydrogen content of 0.4%, 5.5g of vinyl MQ silicone resin and 0.017g of platinum catalyst evenly.

[0055] The above composition was coated onto stainless steel sheets and PET films according to the method of GB 7124-2008 to prepare shear samples. After curing at 120°C for 2 hours, addition-type silicone rubber adhesive sealant was obtained. The shear strength of stainless steel and PET was tested respectively. The above composition was then used to prepare a 200-micron film by calendering. After curing at 120°C for 2 hours, the transmittance and haze of the film were measured on a TH-100 haze meter.

[0056] The results of shear strength, transmittance, and haze tests are shown in Table 1.

[0057] Example 6

[0058] The preparation of addition-type silicone rubber adhesive sealant 2 is basically the same as in Example 5, except that:

[0059] 0.34g of the boron-containing oligomer 1 obtained in Example 1 was added to the composition, and the rest was the same as in Example 5.

[0060] The shear strength, transmittance, and haze tests were basically the same as in Example 5, except that the shear test specimens and films were prepared using the composition of this example and then tested.

[0061] Example 7

[0062] The preparation of addition-type silicone rubber adhesive sealant 3 is basically the same as in Example 5, except that:

[0063] 0.17g of the boron-containing oligomer 2 obtained in Example 2 was added to the composition, and the rest was the same as in Example 5.

[0064] The shear strength, transmittance, and haze tests were basically the same as in Example 5, except that the samples and films were prepared using the composition of this example and then tested.

[0065] Example 8

[0066] The preparation of addition-cure silicone rubber 4 is basically the same as in Example 5, except that:

[0067] 0.34g of the boron-containing oligomer 2 obtained in Example 2 was added to the composition, and the rest was the same as in Example 5.

[0068] The shear strength, transmittance, and haze tests were basically the same as in Example 5, except that the shear test specimens and films were prepared using the composition of this example and then tested.

[0069] Example 9

[0070] The preparation of addition-type silicone rubber adhesive sealant 5 is basically the same as in Example 5, except that:

[0071] 0.17g of the boron-containing oligomer 3 obtained in Example 3 was added to the composition, and the rest was the same as in Example 5.

[0072] The shear strength, transmittance, and haze tests were basically the same as in Example 5, except that the shear test specimens and films were prepared using the composition of this example and then tested.

[0073] Example 10

[0074] The preparation of addition-type silicone rubber adhesive sealant 6 is basically the same as in Example 5, except that:

[0075] 0.34g of the boron-containing oligomer 3 obtained in Example 3 was added to the composition, and the rest was the same as in Example 5.

[0076] The shear strength, transmittance, and haze tests were basically the same as in Example 5, except that the shear test specimens and films were prepared using the composition of this example and then tested.

[0077] Example 11

[0078] The preparation of addition-type silicone rubber adhesive sealant 7 is basically the same as in Example 5, except that:

[0079] 0.17g of the boron-containing oligomer 4 obtained in Example 4 was added to the composition, and the rest was the same as in Example 5.

[0080] The shear strength, transmittance, and haze tests were basically the same as in Example 5, except that the shear test specimens and films were prepared using the composition of this example and then tested.

[0081] Example 12

[0082] The preparation of addition-type silicone rubber adhesive sealant 8 is basically the same as in Example 5, except that:

[0083] 0.34g of the boron-containing oligomer 4 obtained in Example 4 was added to the composition, and the rest was the same as in Example 5.

[0084] The shear strength, transmittance, and haze tests were basically the same as in Example 5, except that the shear test specimens and films were prepared using the composition of this example and then tested.

[0085] Example 13

[0086] Aging test:

[0087] The shear samples and films prepared on stainless steel sheets and PET films obtained in Example 5 were placed in a constant temperature and humidity chamber and aged for 168 hours at 85°C and 85% relative humidity to simulate a 1000-hour aging experiment. The shear strength and light transmittance of the aged samples were then tested.

[0088] Example 14

[0089] The aging experiment in this embodiment is basically the same as that in Example 13, except that the shear sample and film of Example 7 are used for the aging test, and the shear strength and transmittance of the obtained aged sample are tested.

[0090] Example 15

[0091] The aging experiment in this embodiment is basically the same as that in Example 13, except that the shear sample and film of Example 9 are used for the aging test, and the shear strength and transmittance of the obtained aged sample are tested.

[0092] Example 16

[0093] The aging experiment in this embodiment is basically the same as that in Example 13, except that the shear sample and film of Example 11 are used for the aging test, and the shear strength and transmittance of the obtained aged sample are tested.

[0094] Comparative Example 1

[0095] A composition was prepared by uniformly mixing 8.5g of vinyl-terminated silicone oil with a viscosity of 100000mPa.s, 3g of hydrogen-containing MQ silicone resin with a hydrogen content of 0.4%, 5.5g of vinyl MQ silicone resin, and 0.017g of platinum catalyst. The composition was then coated onto stainless steel sheet and PET film to prepare shear samples, which were cured at 120°C for 2 hours. The composition was then coated into a 200-micron film using a calender.

[0096] Referring to Example 5, the shear strength, light transmittance, and haze of the shear sample of this comparative example were tested respectively, and the test results are shown in Table 1.

[0097] Comparative Example 2

[0098] 0.17g vinyltriethoxysilane, 8.5g vinyl-terminated silicone oil with a viscosity of 100000mPa.s, 3g hydrogen-containing MQ silicone resin with a hydrogen content of 0.4%, 5.5g vinyl MQ silicone resin and 0.017g platinum catalyst were mixed evenly and coated onto stainless steel sheet and PET film respectively to prepare shear samples. The samples were cured at 120℃ for 2h and then coated into a 200-micron film in a calender.

[0099] Referring to Example 5, the shear strength, light transmittance, and haze of the shear sample of this comparative example were tested respectively, and the test results are shown in Table 1.

[0100] Comparative Example 3

[0101] 0.17g of methylvinyldiethoxysilane, 8.5g of vinyl-terminated silicone oil with a viscosity of 100000mPa.s, 3g of hydrogen-containing MQ silicone resin with a hydrogen content of 0.4%, 5.5g of vinyl MQ silicone resin and 0.017g of platinum catalyst were mixed evenly and coated onto stainless steel sheet and PET film respectively to prepare shear samples. The mixture was cured at 120℃ for 2h and then coated into a 200-micron film in a calender.

[0102] Referring to Example 5, the shear strength, light transmittance, and haze of the shear sample of this comparative example were tested respectively, and the test results are shown in Table 1.

[0103] Comparative Example 4

[0104] A borate ester tackifier was prepared according to Example 3 of Chinese Patent CN201410748954.0. 0.17g of the borate ester tackifier, 8.5g of vinyl-terminated silicone oil with a viscosity of 100000mPa.s, 3g of hydrogen-containing MQ silicone resin with a hydrogen content of 0.4%, 5.5g of vinyl MQ silicone resin and 0.017g of platinum catalyst were mixed evenly and coated onto stainless steel sheet and PET film respectively to prepare shear samples. The samples were cured at 120°C for 2h and then coated into a 200-micron film in a calender.

[0105] Referring to Example 5, the shear strength, light transmittance, and haze of the shear sample of this comparative example were tested respectively, and the test results are shown in Table 1.

[0106] Comparative Example 5

[0107] A boron-containing small molecule tackifier was prepared according to Example 4 of Chinese Patent CN201410725194.1. 0.17g of the boron-containing small molecule tackifier, 8.5g of vinyl-terminated silicone oil with a viscosity of 100000mPa.s, 3g of hydrogen-containing MQ silicone resin with a hydrogen content of 0.4%, 5.5g of vinyl MQ silicone resin, and 0.017g of platinum catalyst were mixed evenly and coated onto stainless steel sheet and PET film respectively to prepare shear samples. The samples were cured at 120°C for 2h and then coated into a 200-micron film in a calender.

[0108] Referring to Example 5, the shear strength, light transmittance, and haze of the shear sample of this comparative example were tested respectively, and the test results are shown in Table 1.

[0109] Table 1

[0110] Example 5 4.6 3.5 93.8 1.04 Example 6 5.72 3.86 93.6 1.13 Example 7 3.87 4.03 94.1 2.59 Example 8 4.89 4.59 94.2 2.31 Example 9 4.35 3.21 93.9 0.88 Example 10 4.37 3.17 94 1.63 Example 11 5.16 4.05 93.8 1.43 Example 12 6.18 4.43 93.5 1.89 Example 13 4.43 2.96 92.7 3.14 Example 14 3.91 3.27 93.1 4.17 Example 15 4.07 2.81 93.7 2.61 Example 16 4.91 3.64 92.4 3.49 Comparative Example 1 3.25 2.35 94.4 1.02 Comparative Example 2 4.47 2.28 94.1 1.64 Comparative Example 3 4.15 2.83 94.6 1.81 Comparative Example 4 4.42 3.45 84.3 4.84 Comparative Example 5 5.44 3.87 81.7 4.47

[0111] As shown in Table 1, traditional addition-cure silicone rubber exhibits poor adhesion to stainless steel and PET films. The addition of vinyltriethoxysilane and methylvinyldiethoxysilane provides some improvement, increasing the shear strength of stainless steel substrates by up to 37% and PET substrates by up to 20%. Furthermore, the addition of the boron-containing oligomers described in this invention as tackifiers significantly enhances adhesion, with greater improvement occurring with higher addition amounts. Shear strength of stainless steel substrates can be increased by up to 90%, and PET substrates by up to 95%. Moreover, as shown in Table 1 and... Figure 5 The data shows that adding the boron-containing oligomer as a tackifier in this invention does not significantly affect the transmittance and haze of the addition-cure silicone rubber adhesive sealant system. However, the UV-Vis absorption spectrum reveals that the addition of boron-containing small-molecule tackifiers and borate ester tackifiers significantly affects the transmittance of the addition-cure silicone rubber adhesive sealant system in the UV-Vis band. After aging for 168 hours at 85°C and 85% relative humidity, the adhesion strength to stainless steel and PET films was well maintained, and no significant decrease in transmittance or haze was observed.

[0112] The exemplary embodiments of the present invention have been described above. However, the scope of protection of this application is not limited to the above embodiments. Any modifications, equivalent substitutions, improvements, etc., made by those skilled in the art within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. An addition-cure silicone rubber composition, characterized in that, The addition-cure silicone rubber composition comprises the following components: an addition-cure silicone rubber base, reinforcing filler, tackifier, and catalyst, wherein the tackifier includes boron-containing oligomers; and the reinforcing filler is selected from vinyl MQ silicone resin. The boron-containing oligomer is a boron-containing oligomer containing unsaturated bonds; the unsaturated bonds are selected from large π bonds and carbon-carbon double bonds; the boron-containing oligomer includes at least one boron-oxygen-silicon bond; The method for preparing the boron-containing oligomer includes: performing a condensation reaction between a small molecule alkoxysilane containing unsaturated bonds and a compound containing active boron hydroxyl groups to obtain the boron-containing oligomer; the mass fraction of the reactants in the reaction system is 5%-10%, and the reactants include a small molecule alkoxysilane containing unsaturated bonds and a compound containing active boron hydroxyl groups; a condensation catalyst is also added during the condensation reaction. The molar ratio of the small molecule alkoxysilane containing unsaturated bonds to the compound containing active boron hydroxyl groups is 1:0.3-1; The small molecule alkoxysilane containing unsaturated bonds is vinyltrimethoxysilane or methylvinyldiethoxysilane; The compound containing an active boron hydroxyl group is 4-vinylphenylboronic acid; The polycondensation catalyst is an anion exchange resin.

2. The addition-cure silicone rubber composition according to claim 1, characterized in that, The temperature of the condensation reaction is 30-100℃; The pressure of the reaction system for the condensation reaction is maintained at 0.01 MPa-2 MPa; The anion exchange resin is selected from at least one of the following: FPA53 anion exchange resin, 717 strong base styrene-based anion exchange resin, D392 macroporous anion exchange resin, LX-TS4 macroporous strong base anion exchange resin, IRA-411 anion exchange resin, D900 macroporous weak base anion exchange resin, Q strong anion exchange resin Rigose Q, and DEAE weak anion exchange resin Rigose DEAE HiRes.

3. The addition-cure silicone rubber composition according to claim 1, characterized in that, A solvent is also added to the condensation reaction so that the reaction system is carried out in a solvent environment; the solvent is selected from at least one of ethanol, methanol, toluene, ethyl acetate, tetrahydrofuran, acetone, acetonitrile, n-hexane, dichloromethane, isopropanol, xylene, and petroleum ether.

4. The addition-cure silicone rubber composition according to claim 1, characterized in that, The mass of the reinforcing filler is 30%-100% of the mass of the addition-type silicone rubber base; The tackifier is 0.5%-3% of the mass of the addition-type silicone rubber base.

5. The addition-cure silicone rubber composition according to claim 1, characterized in that, The catalyst is selected from platinum catalysts; The mass of the platinum catalyst is 0.5‰-2‰ of the mass of the addition-type silicone rubber base.

6. The addition-cure silicone rubber composition according to claim 1, characterized in that, The addition-type silicone rubber base comprises a mixture of vinyl-terminated silicone oil and hydrogen-containing MQ silicone resin; In the addition-type silicone rubber base adhesive, the mass ratio of the end vinyl silicone oil to the hydrogen-containing MQ silicone resin is 1-10:0.1-5.

7. An adhesive sealant, characterized in that, The adhesive sealant is prepared from the addition-type silicone rubber composition according to any one of claims 1-6.

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