Tackifier, one-component addition-type silicone sealant, and preparation method therefor

Abstract

Disclosed are a tackifier, a one-component addition-type silicone sealant, and a preparation method therefor. The tackifier is obtained by reaction between tetramethylcyclotetrasiloxane, dimethylmethoxyvinylsilane, and allyl glycidyl ether under the catalysis of a platinum catalyst. The tackifier is used in the preparation of an addition-type silicone sealant, which can achieve effective adhesion to metal substrates while improving the phenomenon of anti-sticking of silicone sealants on reverse cover plates. Furthermore, by using the novel tackifier prepared by the present invention, a vinyl-terminated silicone oil, fumed silica, a hydrogen-containing crosslinking agent, fumed titanium dioxide, and a release modifier as raw materials, the prepared one-component addition-type silicone sealant not only has excellent adhesion to metal substrates, but also does not produce adhesion and sticking to a reverse contact substrate during long-term high-temperature baking after compression, and has excellent anti-compression and anti-sticking properties.

Description

Tackifier, one-component addition-type silicone sealant and preparation method thereof

[0001] The present invention claims priority to Chinese patent application No. 2023117961575, filed with the Patent Office of China on December 25, 2023, entitled “Tackifier, one-component addition-type silicone sealant and preparation method thereof”, the entire contents of which are incorporated herein by reference. Technical Field

[0002] The present invention relates to the technical field of sealants, in particular to a tackifier, a single-component addition-type organosilicon sealant and a preparation method thereof. Background Art

[0003] The core components of new energy electric vehicles include power batteries, electric drive systems, and high-voltage electronic control systems. All require sealants / sealing rings to ensure a waterproof enclosure, isolating them from water, dust, oil, and other impurities, meeting IP67 protection standards.

[0004] There are three main processes for sealing systems in new energy vehicles: the seal ring process, the FIPG process, and the CIPG process. The traditional seal ring process involves installing a preformed seal ring on the sealing surface and then press-fitting it to achieve a seal. This process offers the advantage of high dimensional accuracy of the molded seal ring, but it requires manual operation and cannot be automated with glue dispensing. Manual installation suffers from poor precision and consistency, and requires the production of various molds tailored to different sealing structures, resulting in high mold costs. The FIPG process, also known as the "wet assembly method," involves applying liquid sealant to the sealing surface and assembling the product while the sealant is still uncured. The assembly then requires a period of time to allow the sealant to fully cure and ensure a good bond between the upper and lower contacting sealing panels, achieving a seal. This process offers the advantage of automated glue dispensing and high sealing reliability, but since both sealing surfaces are bonded, subsequent repairs are difficult. The CIPG process, also known as the "dry assembly method," applies a liquid sealant (typically a heat-curing addition silicone rubber) to the sealing surface and then mechanically locks (i.e., compresses) the seal to provide a secure seal. This process combines the advantages of traditional sealing rings and FIPG. It not only realizes the automatic dispensing process, but also facilitates subsequent disassembly and maintenance due to the use of single-sided bonding.

[0005] At present, the CIPG process generally uses heat-curing single-component addition-type silicone sealant. However, this product usually has the problem of back-sticking after high-temperature aging. That is, after the cured glue line is compressed and aged at high temperature, it also adheres or sticks to the reverse material, making it difficult to disassemble and the glue line is easily damaged and cannot be used again. Summary of the Invention

[0006] Based on this, the object of the present invention is to provide a one-component addition-type silicone sealant with anti-compression and anti-sticking properties.

[0007] In order to achieve the above-mentioned purpose, the present invention includes the following technical solutions.

[0008] In one aspect, the present invention provides a tackifier that effectively bonds to metal substrates while also improving the reverse adhesion of silicone sealants to the back cover. The tackifier is obtained by reacting tetramethylcyclotetrasiloxane, dimethylmethoxyvinylsilane, and allyl glycidyl ether under the catalytic action of a platinum catalyst.

[0009] In a second aspect, the present invention provides a method for preparing the tackifier, comprising the following steps:

[0010] An organic solvent, tetramethylcyclotetrasiloxane and a platinum catalyst are added to a reactor and stirred evenly; the resulting mixture is heated to 60° C. to 80° C. under inert gas protection, and the allyl glycidyl ether and dimethylmethoxyvinylsilane are added dropwise respectively, and the reaction is carried out for 2 h to 3 h; low-boiling substances, the organic solvent and the platinum catalyst are removed to obtain the tackifier.

[0011] In a third aspect, the present invention provides a one-component addition-type organosilicon sealant, the raw materials for preparing the one-component addition-type organosilicon sealant include the tackifier of the present invention.

[0012] Preferably, the raw materials for preparing the one-component addition-type silicone sealant include a platinum catalyst and the following components in parts by weight:

[0013] The amount of the platinum catalyst used is 0.5ppm to 10ppm based on the mass of platinum;

[0014] The release agent is fluorine-containing silane.

[0015] Preferably, the release agent is selected from one or a combination of trifluoropropyldimethylmethoxysilane (dimethylmethoxy(3,3,3-fluoropropyl)silane), trifluoropropyldimethylethoxysilane, trifluoropropylmethyldimethoxysilane and trifluoropropylmethyldiethoxysilane.

[0016] In a fourth aspect, the present invention further provides a method for preparing the one-component addition-type silicone sealant, comprising the following steps:

[0017] (1) adding the vinyl-terminated silicone oil into a kneader, then adding fumed silica in batches, kneading for 1 to 2 hours, then heating to 120 to 150° C. and evacuating, kneading for 2 to 4 hours to obtain a base material;

[0018] (2) adding the base material, hydrogen-containing crosslinking agent and fumed titanium dioxide into a planetary mixer and stirring for 30 to 60 minutes until the mixture is uniform;

[0019] (3) Add the tackifier, inhibitor and release agent into a planetary mixer and stir for 30 to 60 minutes until the mixture is uniform;

[0020] (4) The platinum catalyst is placed in a planetary mixer, stirred and vacuum mixed for 20 to 40 minutes to obtain the one-component addition-type silicone sealant.

[0021] This invention uses tetramethylcyclotetrasiloxane, dimethylmethoxyvinylsilane, and allyl glycidyl ether as raw materials, reacting under the catalytic action of a platinum catalyst to produce a novel tackifier. This tackifier is used in the preparation of an addition-type silicone sealant, achieving effective adhesion to metal substrates while also reducing the silicone sealant's tendency to stick to the back cover.

[0022] Furthermore, a single-component addition-type silicone sealant with excellent anti-compression anti-sticking properties was prepared using the novel tackifier, vinyl-terminated silicone oil, fumed silica, hydrogen-containing crosslinking agent, fumed titanium dioxide, release regulator, etc. prepared by the present invention as raw materials. The homemade tackifier achieves high adhesion to the metal substrate and improves the anti-sticking phenomenon of the silicone sealant to the reverse cover plate to a certain extent; the post-curing of the sealant is effectively controlled by the fumed titanium dioxide, and the hydroxyl groups on the fumed titanium dioxide have a hydrogen bond anchoring effect on the active groups of the residual tackifier in the colloid after curing, which can slow down the migration of the residual tackifier to the reverse substrate; fluorine-containing silane is used as a release regulator, which migrates to the colloid interface (solid-gas interface) to form a release layer, thereby avoiding further reaction between the residual tackifier and the reverse substrate, effectively reducing the risk of anti-sticking. Through the coordinated cooperation of various components, the prepared single-component addition-type silicone sealant not only has excellent bonding properties to metal substrates, but also will not produce adhesion and sticking to the reverse contact substrate after compression and long-term high-temperature baking, and has excellent anti-compression and anti-stick properties. DETAILED DESCRIPTION

[0023] The technical solutions of the present invention are further illustrated by specific examples below. Those skilled in the art should understand that the examples are only for helping to understand the present invention and should not be regarded as specific limitations of the present invention.

[0024] Unless otherwise defined, all technical and scientific terms used in the present invention have the same meaning as those commonly understood by those skilled in the art. The terms used in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0025] The terms "comprise," "comprising," and "having," and any variations thereof, are intended to cover non-exclusive inclusions. For example, a process, method, apparatus, product, or device comprising a series of steps is not limited to the listed steps or modules but may optionally include steps not listed, or other steps inherent to the process, method, product, or device.

[0026] In this application, "plurality" refers to two or more. "And / or" describes the relationship between related objects, indicating that three possible relationships exist. For example, "A and / or B" can mean: A exists alone, A and B exist simultaneously, or B exists alone. The character " / " generally indicates that the related objects are in an "or" relationship.

[0027] In one embodiment, the present invention provides a tackifier obtained by reacting tetramethylcyclotetrasiloxane, dimethylmethoxyvinylsilane, and allyl glycidyl ether under the catalytic action of a platinum catalyst. This tackifier effectively bonds to metal substrates while also reducing the tendency of silicone sealants to stick to the back cover.

[0028] In some embodiments, the mass ratio of tetramethylcyclotetrasiloxane, dimethylmethoxyvinylsilane and allyl glycidyl ether is 50:20-30:15-25.

[0029] In some embodiments, the mass ratio of tetramethylcyclotetrasiloxane, dimethylmethoxyvinylsilane and allyl glycidyl ether is 50:23-27:18-22.

[0030] In some embodiments, the mass ratio of tetramethylcyclotetrasiloxane, dimethylmethoxyvinylsilane and allyl glycidyl ether is 50:25:20.

[0031] In some embodiments, the platinum catalyst is one of chloroplatinic acid, chloroplatinic acid-isopropanol complex, and Custer's catalyst, or a combination thereof.

[0032] In another embodiment of the present invention, the present invention provides a method for preparing the tackifier, comprising the following steps:

[0033] An organic solvent, tetramethylcyclotetrasiloxane and a platinum catalyst are added to a reactor and stirred evenly; the resulting mixture is heated to 60° C. to 80° C. under inert gas protection, and the allyl glycidyl ether and dimethylmethoxyvinylsilane are added dropwise respectively, and the reaction is carried out for 2 h to 3 h; low-boiling substances, the organic solvent and the platinum catalyst are removed to obtain the tackifier.

[0034] In some embodiments, the organic solvent is toluene.

[0035] In some embodiments, the amount of the organic solvent added is 0.8 to 1.2 times the weight of the tetramethylcyclotetrasiloxane.

[0036] In some embodiments, the added amount of the platinum catalyst is 0.5 ppm to 5 ppm based on the mass of platinum.

[0037] In another embodiment of the present invention, the present invention further provides a one-component addition-type organosilicon sealant, the raw materials for preparing the one-component addition-type organosilicon sealant include the tackifier of the present invention.

[0038] In some embodiments, the raw materials for preparing the one-component addition-type silicone sealant include a platinum catalyst and the following components in parts by weight:

[0039] The amount of the platinum catalyst used is 0.5ppm to 10ppm based on the mass of platinum;

[0040] The release agent is fluorine-containing silane.

[0041] In some embodiments, the raw materials for preparing the one-component addition-type silicone sealant include a platinum catalyst and the following components in parts by weight:

[0042] In some embodiments, the release agent is selected from one or a combination of trifluoropropyldimethylmethoxysilane (dimethylmethoxy(3,3,3-fluoropropyl)silane), trifluoropropyldimethylethoxysilane, trifluoropropylmethyldimethoxysilane and trifluoropropylmethyldiethoxysilane.

[0043] In some embodiments, the amount of the platinum catalyst in the one-component addition-type silicone sealant is 3 ppm to 8 ppm based on the mass of platinum.

[0044] In some embodiments, the viscosity of the vinyl-terminated silicone oil at 25° C. is 1000 mPa·s to 100,000 mPa·s, preferably 5000 mPa·s to 20,000 mPa·s; more preferably 8000 mPa·s to 12000 mPa·s.

[0045] In some embodiments, the specific surface area of ​​the fumed silica is 100 m 2 / g~400m 2 / g, preferably 150m 2 / g~250m 2 / g.

[0046] In some embodiments, the hydrogen-containing cross-linking agent is side hydrogen-containing silicone oil and / or terminal hydrogen-containing silicone oil.

[0047] In some embodiments, the hydrogen-containing cross-linking agent has a hydrogen content of 0.2 wt% to 2 wt% and a viscosity of 10 mPa·s to 200 mPa·s.

[0048] In some embodiments, the hydrogen-containing cross-linking agent has a hydrogen content of 0.5 wt% to 1.2 wt% and a viscosity of 20 mPa·s to 120 mPa·s.

[0049] In some embodiments, the inhibitor is selected from one or a combination of 1-ethynyl-1-cyclohexanol, tetramethyltetravinylcyclotetrasiloxane, 2-methyl-3-butynyl-2-ol, 3-methyl-1-hexynyl-3-ol, 3,5-dimethyl-1-hexynyl-3-ol and 3-methyl-1-dodecyn-3-ol.

[0050] In some embodiments, the specific surface area of ​​the fumed titanium dioxide is 30 m 2 / g~100m 2 / g, preferably 40m 2 / g~60m 2 / g.

[0051] In some embodiments, the platinum catalyst is selected from one or a combination of chloroplatinic acid, chloroplatinic acid-isopropanol complex, and Custer's catalyst.

[0052] In another embodiment of the present invention, the present invention also provides a method for preparing the one-component addition-type silicone sealant, comprising the following steps:

[0053] (1) adding the vinyl-terminated silicone oil into a kneader, then adding fumed silica in batches, kneading for 1 to 2 hours, then heating to 120 to 150° C. and evacuating, kneading for 2 to 4 hours to obtain a base material;

[0054] (2) adding the base material, hydrogen-containing crosslinking agent and fumed titanium dioxide into a planetary mixer and stirring for 30 to 60 minutes until the mixture is uniform;

[0055] (3) Add the tackifier, inhibitor and release agent into a planetary mixer and stir for 30 to 60 minutes until the mixture is uniform;

[0056] (4) The platinum catalyst is placed in a planetary mixer, stirred and vacuum mixed for 20 to 40 minutes to obtain the one-component addition-type silicone sealant.

[0057] The viscosity described in the present invention refers to the viscosity under the test condition of 25°C.

[0058] The "vinyl-terminated silicone oil" mentioned in the present invention refers to polydimethylsiloxane with Si-Vi groups at both ends of each molecule, wherein Vi refers to a vinyl group.

[0059] The "side hydrogen-containing silicone oil" mentioned in the present invention refers to polydimethylsiloxane containing Si-H groups, and the Si-H groups are present on the side chains of the molecules rather than at the ends.

[0060] The "terminal hydrogen-containing silicone oil" mentioned in the present invention refers to polydimethylsiloxane with Si-H groups at both ends of each molecule and Si-H groups on the side chain.

[0061] In the following examples, the content of the Custer catalyst is based on the mass of platinum.

[0062] The following are specific examples.

[0063] The preparation method of the homemade tackifier used in the following examples is as follows:

[0064] (1) Add 45 parts by weight of toluene, 50 parts by weight of tetramethylcyclotetrasiloxane and 2 ppm of Custer catalyst into a reactor and stir uniformly at room temperature;

[0065] (2) Raise the temperature to 70°C under nitrogen protection, add 20 parts by weight of allyl glycidyl ether and 25 parts by weight of dimethylmethoxyvinylsilane dropwise, react for 2.5 hours, and then turn off the nitrogen;

[0066] (3) After the reaction is completed, the low-boiling substances and toluene are removed under reduced pressure, and the Custer catalyst is removed by adsorption using activated carbon to obtain the homemade thickener.

[0067] Example 1

[0068] A one-component addition-type silicone sealant, the raw materials of which are as follows:

[0069] The specific preparation method comprises the following steps:

[0070] (1) Adding vinyl-terminated silicone oil into a kneader, and then adding fumed silica in batches, kneading at room temperature for 1 hour, then heating to 120°C and evacuating to -0.09 MPa, and kneading for 3 hours to obtain a base material;

[0071] (2) Add the base material, hydrogen-containing crosslinking agent and fumed titanium dioxide into a planetary mixer and stir for 45 minutes until the mixture is uniform;

[0072] (3) Add the homemade tackifier, inhibitor, and release agent into a planetary mixer and stir for 50 min until the mixture is uniform;

[0073] (4) The catalyst was placed in a planetary mixer, stirred and vacuumed to -0.09 MPa for 30 minutes to obtain the one-component addition-type silicone sealant.

[0074] Example 2

[0075] A one-component addition-type silicone sealant, the raw materials of which are as follows:

[0076] The specific preparation method comprises the following steps:

[0077] (1) Adding vinyl-terminated silicone oil into a kneader, and then adding fumed silica in batches, kneading at room temperature for 1 hour, then heating to 120°C and evacuating to -0.09 MPa, and kneading for 3 hours to obtain a base material;

[0078] (2) Add the base material, hydrogen-containing crosslinking agent and fumed titanium dioxide into a planetary mixer and stir for 45 minutes until the mixture is uniform;

[0079] (3) Add the homemade tackifier, inhibitor, and release agent into a planetary mixer and stir for 50 min until the mixture is uniform;

[0080] (4) The catalyst was placed in a planetary mixer, stirred and vacuumed to -0.09 MPa for 30 minutes to obtain the one-component addition-type silicone sealant.

[0081] Example 3

[0082] A one-component addition-type silicone sealant, the raw materials of which are as follows:

[0083] The specific preparation method comprises the following steps:

[0084] (1) Adding vinyl-terminated silicone oil into a kneader, and then adding fumed silica in batches, kneading at room temperature for 1 hour, then heating to 120°C and evacuating to -0.09 MPa, and kneading for 3 hours to obtain a base material;

[0085] (2) Add the base material, hydrogen-containing crosslinking agent and fumed titanium dioxide into a planetary mixer and stir for 45 minutes until the mixture is uniform;

[0086] (3) Add the homemade tackifier, inhibitor, and release agent into a planetary mixer and stir for 50 min until the mixture is uniform;

[0087] (4) The catalyst was placed in a planetary mixer, stirred and vacuumed to -0.09 MPa for 30 minutes to obtain the one-component addition-type silicone sealant.

[0088] Example 4

[0089] A one-component addition-type silicone sealant, the raw materials of which are as follows:

[0090] The specific preparation method comprises the following steps:

[0091] (1) Adding vinyl-terminated silicone oil into a kneader, and then adding fumed silica in batches, kneading at room temperature for 1 hour, then heating to 120°C and evacuating to -0.09 MPa, and kneading for 3 hours to obtain a base material;

[0092] (2) Add the base material, hydrogen-containing crosslinking agent and fumed titanium dioxide into a planetary mixer and stir for 45 minutes until the mixture is uniform;

[0093] (3) Add the homemade tackifier, inhibitor, and release agent into a planetary mixer and stir for 50 min until the mixture is uniform;

[0094] (4) The catalyst was placed in a planetary mixer, stirred and vacuumed to -0.09 MPa for 30 minutes to obtain the one-component addition-type silicone sealant.

[0095] Example 5

[0096] A one-component addition-type silicone sealant, the raw materials of which are as follows:

[0097] The specific preparation method comprises the following steps:

[0098] (1) Adding vinyl-terminated silicone oil into a kneader, and then adding fumed silica in batches, kneading at room temperature for 1 hour, then heating to 120°C and evacuating to -0.09 MPa, and kneading for 3 hours to obtain a base material;

[0099] (2) Add the base material, hydrogen-containing crosslinking agent and fumed titanium dioxide into a planetary mixer and stir for 45 minutes until the mixture is uniform;

[0100] (3) Add the homemade tackifier, inhibitor, and release agent into a planetary mixer and stir for 50 min until the mixture is uniform;

[0101] (4) The catalyst was placed in a planetary mixer, stirred and vacuumed to -0.09 MPa for 30 minutes to obtain the one-component addition-type silicone sealant.

[0102] Comparative Example 1

[0103] A one-component addition-type silicone sealant, the raw materials of which are as follows:

[0104] The specific preparation method comprises the following steps:

[0105] (1) Adding vinyl-terminated silicone oil into a kneader, and then adding fumed silica in batches, kneading at room temperature for 1 hour, then heating to 120°C and evacuating to -0.09 MPa, and kneading for 3 hours to obtain a base material;

[0106] (2) Add the base material, hydrogen-containing crosslinking agent and fumed titanium dioxide into a planetary mixer and stir for 45 minutes until the mixture is uniform;

[0107] (3) The homemade thickener and inhibitor were placed in a planetary mixer and stirred for 50 min until they were uniformly mixed;

[0108] (4) The catalyst was placed in a planetary mixer, stirred and vacuumed to -0.09 MPa for 30 minutes to obtain the one-component addition-type silicone sealant.

[0109] Comparative Example 2

[0110] A one-component addition-type silicone sealant, the raw materials of which are as follows:

[0111] The specific preparation method comprises the following steps:

[0112] (1) Adding vinyl-terminated silicone oil into a kneader, and then adding fumed silica in batches, kneading at room temperature for 1 hour, then heating to 120°C and evacuating to -0.09 MPa, and kneading for 3 hours to obtain a base material;

[0113] (2) Add the base material and hydrogen-containing crosslinking agent into a planetary mixer and stir for 45 minutes until the mixture is uniform;

[0114] (3) Add the homemade tackifier, inhibitor, and release agent into a planetary mixer and stir for 50 min until the mixture is uniform;

[0115] (4) The catalyst was placed in a planetary mixer, stirred and vacuumed to -0.09 MPa for 30 minutes to obtain the one-component addition-type silicone sealant.

[0116] Comparative Example 3

[0117] A one-component addition-type silicone sealant, the raw materials of which are as follows:

[0118] The specific preparation method comprises the following steps:

[0119] (1) Adding vinyl-terminated silicone oil into a kneader, and then adding fumed silica in batches, kneading at room temperature for 1 hour, then heating to 120°C and evacuating to -0.09 MPa, and kneading for 3 hours to obtain a base material;

[0120] (2) Add the base material, hydrogen-containing crosslinking agent and fumed titanium dioxide into a planetary mixer and stir for 45 minutes until the mixture is uniform;

[0121] (3) Add the commercially available tackifier, inhibitor, and release agent into a planetary mixer and stir for 50 minutes until the mixture is uniform;

[0122] (4) The catalyst was placed in a planetary mixer, stirred and vacuumed to -0.09 MPa for 30 minutes to obtain the one-component addition-type silicone sealant.

[0123] Comparative Example 4

[0124] A one-component addition-type silicone sealant, the raw materials of which are as follows:

[0125] The specific preparation method comprises the following steps:

[0126] (1) Adding vinyl-terminated silicone oil into a kneader, and then adding fumed silica in batches, kneading at room temperature for 1 hour, then heating to 120°C and evacuating to -0.09 MPa, and kneading for 3 hours to obtain a base material;

[0127] (2) Add the base material and hydrogen-containing crosslinking agent into a planetary mixer and stir for 45 minutes until the mixture is uniform;

[0128] (3) The commercially available thickener and inhibitor were placed in a planetary mixer and stirred for 50 min until uniformly mixed;

[0129] (4) The catalyst was placed in a planetary mixer, stirred and vacuumed to -0.09 MPa for 30 minutes to obtain the one-component addition-type silicone sealant.

[0130] Comparative Example 5

[0131] A one-component addition-type silicone sealant, the raw materials of which are as follows:

[0132] The specific preparation method comprises the following steps:

[0133] (1) Adding vinyl-terminated silicone oil into a kneader, and then adding fumed silica in batches, kneading at room temperature for 1 hour, then heating to 120°C and evacuating to -0.09 MPa, and kneading for 3 hours to obtain a base material;

[0134] (2) Add the base material and hydrogen-containing crosslinking agent into a planetary mixer and stir for 45 minutes until the mixture is uniform;

[0135] (3) The homemade thickener and inhibitor were placed in a planetary mixer and stirred for 50 min until they were uniformly mixed;

[0136] (4) The catalyst was placed in a planetary mixer, stirred and vacuumed to -0.09 MPa for 30 minutes to obtain the one-component addition-type silicone sealant.

[0137] The single-component addition-type silicone sealants of the above examples and comparative examples were subjected to the following performance tests:

[0138] 1. Tensile shear strength: Measured in accordance with GB T 7124-2008 Determination of tensile shear strength of adhesives (rigid material to rigid material);

[0139] 2. Compression anti-sticking: High-temperature compression aging is carried out in accordance with GB / T 7759.1-2015 Rubber, vulcanized or thermoplastic — Determination of permanent compression set — Part 1: At room and elevated temperatures. The contact surface is not treated with a lubricant coating. The test conditions are 150°C / 168h and a compression of 25%. The percentage of residual adhesive sticking to the contact surface after the specimen is destroyed is determined.

[0140] The test results are shown in the following table:

[0141] As can be seen from the above table, the tensile shear strength of the one-component addition-type silicone sealants prepared in Examples 1-5 all reached above 3.5 MPa, and no compression back-sticking occurred in any of them; the difference between Comparative Example 1 and Example 5 is that no release regulator was used, resulting in compression back-sticking in the one-component addition-type silicone sealant prepared therefrom, with a back-sticking area of ​​32%; the difference between Comparative Example 2 and Example 5 is that no fumed titanium dioxide was used, resulting in compression back-sticking in the one-component addition-type silicone sealant prepared therefrom, with a back-sticking area of ​​21%; the difference between Comparative Example 3 and Example 5 is that commercial titanium dioxide was used. The tensile shear strength of the prepared one-component addition-type silicone sealant was significantly reduced in tensile shear strength and the compression anti-sticking phenomenon was more serious, with the anti-sticking area reaching 72%; the difference between Comparative Example 4 and Example 5 is that the commercially available tackifier was used, and the fumed titanium dioxide and release regulator were not used, resulting in the prepared one-component addition-type silicone sealant having a more serious compression anti-sticking phenomenon and the anti-sticking area reaching 43%.

[0142] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0143] The above-described embodiments merely represent several implementation methods of the present invention. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent. It should be noted that a person skilled in the art would be able to make various modifications and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the patent for this invention shall be determined by the appended claims.

Claims

1. A tackifier, characterized in that, The tackifier is obtained by reacting tetramethylcyclotetrasiloxane, dimethylmethoxyvinylsilane and allyl glycidyl ether under the catalysis of a platinum catalyst.

2. The tackifier according to claim 1, wherein The platinum catalyst is one or a combination of chloroplatinic acid, chloroplatinic acid-isopropanol complex, and Karstedt's catalyst; and / or, The mass ratio of the tetramethylcyclotetrasiloxane, dimethylmethoxyvinylsilane and allyl glycidyl ether is 50:20-30:15-25.

3. The tackifier according to claim 2, wherein The mass ratio of the tetramethylcyclotetrasiloxane, dimethylmethoxyvinylsilane and allyl glycidyl ether is 50:23-27:18-22.

4. The tackifier according to claim 3, wherein The mass ratio of the tetramethylcyclotetrasiloxane, dimethylmethoxyvinylsilane and allyl glycidyl ether is 50:25:

20.

5. A method for preparing the tackifier according to any one of claims 1-4, characterized in that, It includes the following steps: Add an organic solvent, tetramethylcyclotetrasiloxane and a platinum catalyst into a reactor, and stir evenly; heat the obtained mixture to 60°C-80°C under the protection of an inert gas, and dropwise add the allyl glycidyl ether and dimethylmethoxyvinylsilane respectively, and react for 2h-3h; remove low boilers, organic solvents and platinum catalyst to obtain the tackifier.

6. The preparation method of the tackifier according to claim 5, characterized in that, The organic solvent is toluene; and / or, The addition amount of the organic solvent is 0.8-1.2 times the weight of the tetramethylcyclotetrasiloxane; and / or, Based on the mass of platinum, the addition amount of the platinum catalyst is 0.5ppm-5ppm.

7. A one-component addition-curing silicone sealant, characterized in that, The raw materials for its preparation include the tackifier described in any one of claims 1-4.

8. The one-component addition-curing silicone sealant according to claim 7, wherein, The raw materials for its preparation include a platinum catalyst and the following components in parts by weight: The dosage of the platinum catalyst is 0.5ppm-10ppm based on the mass of platinum; The release regulator is a fluorosilane.

9. The one-component addition-curing silicone sealant according to claim 8, wherein Its preparation raw materials include a platinum catalyst and the following components in parts by weight:

10. The one-component addition-curing silicone sealant according to claim 8 or 9, characterized in that, In the one-component addition-curing silicone sealant, the dosage of the platinum catalyst is 3ppm-8ppm based on the mass of platinum; and / or, The viscosity of the terminal vinyl silicone oil at 25°C is 1000mPa·s-100000mPa·s; and / or, The specific surface area of the fumed silica is 100 m 2 / g to 400 m 2 / g; and / or, The hydrogen-containing crosslinking agent is side hydrogen-containing silicone oil and / or terminal-side hydrogen-containing silicone oil, its hydrogen content is 0.2wt%-2wt%, and the viscosity is 10mPa·s-200mPa·s; and / or, The release regulator is selected from one or a combination of dimethylmethoxy(3,3,3-fluoropropyl)silane, trifluoropropyl dimethyl ethoxysilane, trifluoropropyl methyl dimethoxysilane and trifluoropropyl methyl diethoxysilane; and / or, The inhibitor is selected from one or a combination of 1-ethynyl-1-cyclohexanol, tetramethyltetravinylcyclotetrasiloxane, 2-methyl-3-butyn-2-ol, 3-methyl-1-hexyn-3-ol, 3,5-dimethyl-1-hexyn-3-ol and 3-methyl-1-dodecyn-3-ol; and / or, The specific surface area of the aerosil titanium dioxide is 30 m 2 / g to 100 m 2 / g; and / or, The platinum catalyst is selected from one or a combination of chloroplatinic acid, chloroplatinic acid-isopropanol complex, and Karstedt's catalyst.

11. The one-component addition-curing silicone sealant according to claim 10, wherein, The viscosity of the terminal vinyl silicone oil at 25°C is 5000mPa·s-20000mPa·s; and / or, The specific surface area of the fumed silica is 150 m 2 / g to 250 m 2 / g; and / or, The hydrogen content of the hydrogen-containing crosslinking agent is 0.5wt%-1.2wt%, and the viscosity is 20mPa·s-120mPa·s; and / or, The specific surface area of the aerosil titanium dioxide is 40 m 2 / g to 60 m 2 / g.

12. A method for preparing the one-component addition-curing silicone sealant according to any one of claims 8-11, characterized in that, It includes the following steps: (1) Put the terminal vinyl silicone oil into a kneader, then add the fumed silica in batches, knead for 1 h to 2 h, then heat up to 120 °C to 150 °C and evacuate, and knead for 2 h to 4 h to obtain the base material; (2) Put the base material, hydrogen-containing crosslinking agent and fumed titanium dioxide into a planetary mixer, and stir for 30 min to 60 min after adding until evenly mixed; (3) Put the tackifier, inhibitor and release regulator into a planetary mixer, and stir for 30 min - 60 min until evenly mixed; (4) Put the platinum catalyst into a planetary mixer, stir and evacuate to mix for 20 min to 40 min to obtain the one-component addition-curing silicone sealant.

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