Silica gel, preparation method thereof and electronic product

Abstract

The invention provides silica gel, a preparation method thereof and an electronic product, and relates to the field of silica gel materials. The heat-conducting silicone rubber is prepared from the following raw materials in parts by weight: 30 to 100 parts of modified polyborosiloxane, 100 to 200 parts of vinyl-terminated silicone rubber, 300 to 1000 parts of MDQ silicon resin, 350 to 1100 parts of diluent, 0.5 to 5 parts of first catalyst, 1.5 to 25 parts of hydrogen-containing silicone oil, 80 to 600 parts of heat-conducting filler, 3 to 20 parts of second catalyst and 0.3 to 3 parts of reaction inhibitor. The modified polysiloxane in the silica gel has a reversible dynamic high-energy B-O bond, and can quickly absorb energy when subjected to high-speed impact; the MDQ type resin is used as a tackifying component, so that the flexibility is improved while the pressure sensitivity is ensured, and the impact resistance is further improved; the heat-conducting filler is used as a heat-conducting and antistatic component, and the cured silica gel has good heat-conducting and antistatic properties.

Description

Technical Field

[0001] The present application relates to the field of silicone gel materials, and in particular to silicone gel and a preparation method thereof and an electronic product. Background Art

[0002] With the rapid development of science and technology, people's requirements for electronic display devices such as mobile phones and tablets are becoming increasingly lightweight, ultra-thin and bendable, which makes the requirements for the protection components of display modules more stringent. At present, there are two main ways to protect common display modules. One is to use buffer foam tape, attach glue on both sides of the foam, and bond and fix the lower copper foil, aluminum foil and other fixed layers to the upper display module. However, this solution not only has a complicated assembly process and weak buffer protection performance, but also the inherent pore structure of the foam will be reflected on the screen, affecting the display effect; the second is to use silicone gel, which has a one-time molding process, high assembly efficiency, excellent buffering performance, and large adjustment space, and has gradually become a new development direction for the industry; silicone gel is a viscoelastic body. When electronic products are impacted by external forces, the colloid can be squeezed and deformed to offset and absorb part of the external force, reduce the impact of the external force on the display module, and thus achieve a protective effect; however, since the thermal conductivity of ordinary silicone gel materials is only about 0.1W / mK, local heating is prone to occur when used in electronic display devices such as mobile phones and tablets for a long time, thereby affecting the service life of electronic components.

[0003] Screen protection gel has become a hot topic of research in recent years, and there have been many reports. Among them, Chinese patent CN116063979A provides a method for preparing an antistatic, anti-buffering, high-adhesion silicone pressure-sensitive adhesive, with an anti-buffering property of about 63%, but no mention of thermal conductivity; Chinese patent CN114316896A provides a transparent silicone gel with good impact resistance, but no mention of antistatic and thermal conductivity; Chinese patent CN117757266A provides a method for preparing silicone gel, with an anti-buffering height of up to 66mm, and good anti-indentation and antistatic properties, but no improvement in thermal conductivity; Chinese patent CN112778766A provides a high-reliability, high-thermal conductivity silicone gel composition and its preparation method, which has good thermal conductivity, but no mention of anti-buffering and pressure sensitivity. Moreover, the above reports all use conventional vinyl silicone oil or vinyl silicone rubber raw rubber plus MQ silicone resin, and no further research on the molecular structure is done to improve impact resistance.

[0004] Therefore, it is of great significance to develop a silicone gel that can achieve both thermal conductivity and better buffering effect. Summary of the invention

[0005] The purpose of this application is to provide a silicone gel and a preparation method thereof and an electronic product to solve the above problems.

[0006] In order to achieve the above objectives, the present application provides a silicone gel in a first aspect, wherein the raw materials thereof, measured by weight, include:

[0007] 30-100 parts of modified polyborosiloxane, 100-200 parts of vinyl-terminated silicone rubber, 300-1000 parts of MDQ silicone resin, 350-1100 parts of diluent, 0.5-5 parts of first catalyst, 1.5-25 parts of hydrogenated silicone oil, 80-600 parts of thermal conductive filler, 3-20 parts of second catalyst, 0.3-3 parts of reaction inhibitor;

[0008] The first catalyst includes an acidic catalyst and / or a basic catalyst;

[0009] The second catalyst includes a platinum catalyst.

[0010] Optionally, the silicone gel satisfies at least one of the following conditions:

[0011] A. The modified polyborosiloxane is prepared by high-temperature condensation of vinyl hydroxy silicone oil and boric acid compounds;

[0012] The boric acid compound includes boric acid and / or borate ester compound;

[0013] B. The molecular weight of the vinyl terminated silicone rubber is 500,000-900,000;

[0014] C. The vinyl content in the vinyl terminated silicone rubber accounts for 0.04% to 0.4% of the total content.

[0015] Optionally, the silicone gel satisfies at least one of the following conditions:

[0016] A. The molecular weight of the MDQ silicone resin is 5000-10000;

[0017] B. The molar ratio of M:D:Q in the MDQ silicone resin is (0.5-1):(1-3):1;

[0018] C. The hydroxyl content in the MDQ silicone resin accounts for 0.1%-1% of the total mass.

[0019] Optionally, the silicone gel satisfies at least one of the following conditions:

[0020] A. The diluent includes one or more of toluene, xylene, trimethylbenzene, and alkane solvents;

[0021] B. The thermally conductive filler includes nanographene;

[0022] C. The reaction inhibitor includes one or more of acetylene cyclohexanol, 2-methyl-3-butyn-2-ol, and 1-(1-propynyl)cyclohexanol.

[0023] Optionally, the platinum content of the platinum catalyst is 3000ppm-5000ppm.

[0024] Optionally, the silicone gel satisfies at least one of the following conditions:

[0025] A. The hydrogen content of the hydrogen-containing silicone oil is 0.3wt%-1.5wt%;

[0026] B. The number of active hydrogen atoms in a single molecule of the hydrogen-containing silicone oil is greater than or equal to 3.

[0027] The second aspect of the present application provides a method for preparing a silicone gel, comprising:

[0028] The raw materials are mixed to obtain the silica gel.

[0029] Optionally, the mixing comprises:

[0030] The modified polyborosiloxane, the vinyl-terminated silicone rubber, the MDQ silicone resin, and the diluent are first mixed to obtain a first mixed material;

[0031] Performing a second mixing of the first mixed material and the first catalyst to obtain a second mixed material, and performing a first heat treatment on the second mixed material to obtain a base material;

[0032] The base material, the hydrogen-containing silicone oil, the thermal conductive filler, the diluent, the second catalyst and the inhibitor are mixed for the third time to obtain a third mixture, and the third mixture is subjected to solid-liquid separation and a second heat treatment to obtain the silicone gel.

[0033] Optionally, the method for preparing the silicone gel satisfies at least one of the following conditions:

[0034] A. The first mixing time is 30min-60min, and the temperature is 60℃-100℃;

[0035] B. The temperature of the first heat treatment is 110°C-130°C, and the time is 3h-5h;

[0036] C. After the first heat treatment, vacuum treatment is performed to obtain the base material, the vacuum treatment time is 20min-40min, the temperature is 120°C-140°C, and the vacuum degree is -0.05MPa--0.1MPa;

[0037] D. The pore size of the solid-liquid separation is 10 μm-60 μm;

[0038] E. The temperature of the second heat treatment is 100°C-150°C, and the time is 5min-15min.

[0039] A third aspect of the present application provides an electronic product, comprising the silicone gel or the silicone gel prepared by the silicone gel preparation method.

[0040] Compared with the prior art, the beneficial effects of this application include:

[0041] The silicone gel provided by the present application: modified polysiloxane is used instead of ordinary polysiloxane, and the reversible dynamic high-energy BO bond in the modified polysiloxane can quickly absorb energy when subjected to high-speed impact; MDQ-type resin is used as a viscosity-increasing component, and due to the introduction of D links, while ensuring pressure sensitivity, the flexibility of the resin is also improved, and the impact resistance is further improved; thermally conductive fillers are used as thermally conductive and antistatic components, and the cured silicone gel has good thermal conductivity and antistatic properties; by subjecting polyborosiloxane, vinyl silicone rubber and MDQ silicone resin to a high-temperature reaction, the molecular chain is further extended, which can better improve the tensile strength and impact resistance of the material.

[0042] The preparation method of the silicone gel provided in the present application has a simple production process, is easy to implement, has low raw material cost, and is easy to control quality.

[0043] The electronic product provided by the present application has a long service life. DETAILED DESCRIPTION

[0044] As used herein:

[0045] "Prepared from" is synonymous with "comprising." As used herein, the terms "comprising," "including," "having," "containing," or any other variation thereof, are intended to cover a non-exclusive inclusion. For example, a composition, process, method, article, or apparatus that comprises the listed elements is not necessarily limited to only those elements but may include other elements not expressly listed or inherent to such composition, process, method, article, or apparatus.

[0046] The conjunction "consisting of excludes any unspecified element, step, or component. If used in a claim, this phrase renders the claim closed-ended so that it does not include materials other than those described, except for conventional impurities associated therewith. When the phrase "consisting of" appears in a clause of the body of a claim rather than immediately following the subject matter, it limits only the elements described in that clause; other elements are not excluded from the claim as a whole.

[0047] When an amount, concentration, or other value or parameter is expressed as a range, a preferred range, or a range defined by a series of upper preferred values ​​and lower preferred values, this should be understood as specifically disclosing all ranges formed by any pairing of any range upper limit or preferred value with any range lower limit or preferred value, regardless of whether the range is disclosed separately. For example, when a range of "1 to 5" is disclosed, the described range should be interpreted as including ranges "1 to 4", "1 to 3", "1 to 2", "1 to 2 and 4 to 5", "1 to 3 and 5", etc. When a numerical range is described in this article, unless otherwise stated, the range is intended to include its end values ​​and all integers and fractions within the range.

[0048] In these examples, parts and percentages are by mass unless otherwise indicated.

[0049] "Parts by mass" refers to the basic unit of measurement for expressing the mass ratio of multiple components. 1 part can represent any unit mass, such as 1g or 2.689g. If we say that the mass of component A is a parts and the mass of component B is b parts, it means the ratio of the mass of component A to the mass of component B is a:b. Alternatively, it means that the mass of component A is aK and the mass of component B is bK (K is an arbitrary number, indicating a multiple factor). It should not be misunderstood that, unlike the mass parts, the sum of the mass of all components is not limited to 100 parts.

[0050] "And / or" is used to indicate that one or both of the stated situations may occur, for example, A and / or B includes (A and B) and (A or B).

[0051] In a first aspect, the present application provides a silicone gel, wherein the raw materials thereof, measured by weight, include:

[0052] 30-100 parts of modified polyborosiloxane, 100-200 parts of vinyl-terminated silicone rubber, 300-1000 parts of MDQ silicone resin, 350-1100 parts of diluent, 0.5-5 parts of first catalyst, 1.5-25 parts of hydrogenated silicone oil, 80-600 parts of thermal conductive filler, 3-20 parts of second catalyst, 0.3-3 parts of reaction inhibitor;

[0053] Optionally, the raw materials of the silicone gel are measured by weight: the modified polyborosiloxane can be 30 parts, 40 parts, 50 parts, 60 parts, 70 parts, 80 parts, 90 parts, 100 parts or any value between 30 parts and 100 parts; the vinyl-terminated silicone rubber can be 100 parts, 150 parts, 200 parts or any value between 100 parts and 200 parts; the MDQ silicone resin can be 300 parts, 400 parts, 500 parts, 600 parts, 700 parts, 800 parts, 900 parts, 1000 parts or any value between 300 parts and 1000 parts; the diluent can be 350 parts, 400 parts, 500 parts, 600 parts, 700 parts, 800 parts, 900 parts, 1000 parts, 1100 parts or any value between 350 parts and 1100 parts. any value between , the first catalyst can be 0.5 parts, 1 parts, 1.5 parts, 2 parts, 2.5 parts, 3 parts, 3.5 parts, 4 parts, 5 parts or any value between 0.5 parts and 5 parts, the hydrogen-containing silicone oil can be 1.5 parts, 5 parts, 10 parts, 15 parts, 20 parts, 25 parts or any value between 1.5 parts and 25 parts, the thermal conductive filler can be 80 parts, 100 parts, 200 parts, 300 parts, 400 parts, 500 parts, 600 parts or any value between 80 parts and 600 parts, the second catalyst can be 3 parts, 5 parts, 10 parts, 15 parts, 20 parts or any value between 3 parts and 20 parts, and the reaction inhibitor can be 0.3 parts, 0.5 parts, 1 parts, 2 parts, 3 parts or any value between 0.3 parts and 3 parts;

[0054] The first catalyst includes an acidic catalyst and / or a basic catalyst;

[0055] Optionally, the acidic catalyst includes one or more of acetic acid, benzoic acid, and propionic acid;

[0056] Optionally, the alkaline catalyst includes one or more of ammonia, organic amine, and alkali metal hydroxide;

[0057] The second catalyst includes a platinum catalyst.

[0058] In some embodiments, the silicone gel satisfies at least one of the following conditions:

[0059] A. The modified polyborosiloxane is prepared by high-temperature condensation of vinyl hydroxy silicone oil and boric acid compounds;

[0060] The boric acid compound includes boric acid and / or borate ester compound;

[0061] B. The molecular weight of the vinyl terminated silicone rubber is 500,000-900,000;

[0062] Optionally, the molecular weight of the vinyl terminated silicone rubber may be 500,000, 600,000, 700,000, 800,000, 900,000, or any value between 500,000 and 900,000;

[0063] C. The vinyl content in the vinyl terminated silicone rubber accounts for 0.04% to 0.4% of the total content.

[0064] Optionally, the vinyl content in the vinyl terminated silicone rubber accounts for 0.04%, 0.1%, 0.2%, 0.3%, 0.4% or any value between 0.04% and 0.4% of the total content.

[0065] It should be noted that when the molecular weight of the vinyl-terminated silicone rubber is 500,000-900,000 and the vinyl content accounts for 0.04%-0.4% of the total content, the resulting pressure-sensitive adhesive has better elasticity and flexibility, and is beneficial for impact resistance.

[0066] In some embodiments, the silicone gel satisfies at least one of the following conditions:

[0067] A. The molecular weight of the MDQ silicone resin is 5000-10000;

[0068] Optionally, the molecular weight of the MDQ silicone resin may be 5000, 6000, 7000, 8000, 9000, 10000 or any value between 5000-10000;

[0069] It should be noted that MDQ silicone resin is a type of MQ silicone resin, which consists of a monofunctional silicon-oxygen chain (R 1 R 2 R 3 SiO 1 / 2 , M chain), difunctional siloxane chain (R 4 R 5 SiO 2 / 2 , D chain) and tetrafunctional silicon-oxygen chain (SiO 4 / 2 , Q chain segment) is formed by co-hydrolysis-polycondensation reaction of an organosilicon compound.

[0070] B. The molar ratio of M:D:Q in the MDQ silicone resin is (0.5-1):(1-3):1;

[0071] Optionally, the molar ratio of M:Q in the MDQ silicone resin may be any value between 0.5:1, 0.6:1, 0.7:1, 0.8:1, 0.9:1, 1:1 or (0.5-1):1, and the mass ratio of D:Q may be any value between 1:1, 2:1, 3:1 or (1-3):1;

[0072] It should be noted that the molar ratio of M:D:Q is (0.5-1):(1-3):1, which can be understood as: the molar ratio of the total monofunctional silicon-oxygen chain, the difunctional silicon-oxygen chain and the tetrafunctional silicon-oxygen chain is (0.5-1):(1-3):1;

[0073] C. The hydroxyl content in the MDQ silicone resin accounts for 0.1%-1% of the total mass.

[0074] Optionally, the hydroxyl content in the MDQ silicone resin is 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1% or any value between 0.1% and 1% of the total mass.

[0075] It should be noted that the hydroxyl content in MDQ silicone resin accounts for 0.1%-1% of the total mass, and the pressure-sensitive adhesive prepared therefrom has better adhesion and heat resistance stability.

[0076] In some embodiments, the silicone gel satisfies at least one of the following conditions:

[0077] A. The diluent includes one or more of toluene, xylene, trimethylbenzene, and alkane solvents;

[0078] B. The thermally conductive filler includes nanographene;

[0079] C. The reaction inhibitor includes one or more of acetylene cyclohexanol, 2-methyl-3-butyn-2-ol, and 1-(1-propynyl)cyclohexanol.

[0080] It should be noted that the reaction inhibitor defined in the present application can inhibit the reaction rate and increase the operable time.

[0081] In some embodiments, the platinum content of the platinum catalyst is 3000 ppm-5000 ppm.

[0082] Optionally, the platinum content of the platinum catalyst may be 3000 ppm, 3500 ppm, 4000 ppm, 4500 ppm, 5000 ppm or any value between 3000 ppm and 5000 ppm.

[0083] In some embodiments, the silicone gel satisfies at least one of the following conditions:

[0084] A. The hydrogen content of the hydrogen-containing silicone oil is 0.3wt%-1.5wt%;

[0085] Optionally, the hydrogen content of the hydrogen-containing silicone oil may be 0.3wt%, 0.5wt%, 1wt%, 1.5wt% or any value between 0.3wt% and 1.5wt%;

[0086] B. The number of active hydrogen atoms in a single molecule of the hydrogen-containing silicone oil is greater than or equal to 3.

[0087] Optionally, the number of active hydrogen atoms in a single molecule of the hydrogen-containing silicone oil may be 3, 4, 5, 6, 10, 20 or any value greater than or equal to 3.

[0088] It should be noted that when the number of active hydrogen atoms in a single molecule of hydrogen-containing silicone oil is less than 3, a cross-linking reaction cannot be formed.

[0089] The second aspect of the present application provides a method for preparing a silicone gel, comprising:

[0090] The raw materials are mixed to obtain the silica gel.

[0091] In some embodiments, the mixing comprises:

[0092] The modified polyborosiloxane, the vinyl-terminated silicone rubber, the MDQ silicone resin, and the diluent are first mixed to obtain a first mixed material;

[0093] Performing a second mixing of the first mixed material and the first catalyst to obtain a second mixed material, and performing a first heat treatment on the second mixed material to obtain a base material;

[0094] It should be noted that modified polyborosiloxane, vinyl-terminated silicone rubber, and MDQ silicone resin contain a large amount of hydroxyl groups. Under the action of the first catalyst, the first heat treatment is performed to cause a hydroxyl condensation reaction to occur, thereby reducing the hydroxyl content and increasing the molecular weight.

[0095] The base material, the hydrogen-containing silicone oil, the thermal conductive filler, the diluent, the second catalyst and the inhibitor are mixed for the third time to obtain a third mixture, and the third mixture is subjected to solid-liquid separation and a second heat treatment to obtain the silicone gel.

[0096] In some embodiments, the method for preparing the silicone gel satisfies at least one of the following conditions:

[0097] A. The first mixing time is 30 to 60 minutes and the temperature is 60 to 100°C;

[0098] B. The temperature of the first heat treatment is 110°C-130°C, and the time is 3h-5h;

[0099] Optionally, the temperature of the first heat treatment may be 110°C, 115°C, 120°C, 125°C, 130°C or any value between 110°C and 130°C, and the time may be 3h, 3.5h, 4h, 4.5h, 5h or any value between 3h and 5h;

[0100] C. After the first heat treatment, vacuum treatment is performed to obtain the base material, the vacuum treatment time is 20 to 40 minutes, the temperature is 120 to 140° C., and the vacuum degree is -0.05 to -0.1 MPa;

[0101] It should be noted that the purpose of vacuum treatment is to remove small molecules that have not reacted completely and the generated water.

[0102] D. The pore size of the solid-liquid separation is 10 μm-60 μm;

[0103] Optionally, the pore size for solid-liquid separation may be 10 μm, 20 μm, 30 μm, 40 μm, 50 μm, 60 μm or any value between 10 μm and 60 μm;

[0104] It should be noted that solid-liquid separation includes filtration, which can remove particulate matter and impurities.

[0105] E. The temperature of the second heat treatment is 100°C-150°C, and the time is 5min-15min.

[0106] Optionally, the temperature of the second heat treatment can be 100°C, 110°C, 120°C, 130°C, 140°C, 150°C or any value between 100°C and 150°C, and the time can be 5 min, 10 min, 15 min or any value between 5 min and 15 min.

[0107] A third aspect of the present application provides an electronic product, comprising the silicone gel or the silicone gel prepared by the silicone gel preparation method.

[0108] The embodiments of the present application will be described in detail below in conjunction with specific examples, but it will be appreciated by those skilled in the art that the following examples are only used to illustrate the present application and should not be considered as limiting the scope of the present application. If specific conditions are not specified in the examples, they are carried out according to normal conditions or the conditions recommended by the manufacturer. If the manufacturer is not specified in the reagents or instruments used, they are all conventional products that can be purchased commercially.

[0109] Example 1

[0110] In a first aspect, the present embodiment provides a silicone gel, wherein the raw materials, measured by weight, include:

[0111] Modified polyborosiloxane, vinyl-terminated silicone rubber, MDQ silicone resin, diluent, first catalyst, hydrogenated silicone oil, thermal conductive filler, second catalyst, reaction inhibitor, specific usage ratios can be referred to Table 1 and Table 2.

[0112] Among them, the modified polyborosiloxane is prepared by high-temperature condensation of vinyl hydroxy silicone oil and boric acid and / or borate ester compounds, and the mass fraction of vinyl in the modified polyborosiloxane is 0.1%, and the mass fraction of hydroxyl is 0.2%; the molecular weight of the vinyl-terminated methyl vinyl silicone rubber is 600,000, and the vinyl content accounts for 0.07% of the total content; the molecular weight of MDQ silicone resin is 5500, the mass ratio of M:D:Q is 0.8:2:1, and the hydroxyl content accounts for 0.6% of the total mass; the platinum content of the platinum catalyst is 4000ppm; the hydrogen content of the hydrogen-containing silicone oil is 0.8wt%, and the number of active hydrogen in a single molecule is greater than or equal to 3; the single layer thickness of the nanographene powder is 50nm.

[0113] A second aspect of the present embodiment provides a method for preparing a silicone gel, comprising:

[0114] S1: Add modified polyborosiloxane, vinyl-terminated methyl vinyl silicone rubber, MDQ silicone resin and toluene into a reactor, heat to 80°C, stir for 40 minutes to dissolve the above raw materials, then add the first catalyst triethylamine, heat to 110°C and reflux for 3 hours. After the reaction is completed, heat to 130°C and dehumidify for 0.5 hours in a vacuum environment of -0.08MPa, and cool to obtain the base material;

[0115] S2: After the base material, 2-methyl-3-butyne-2-ol, hydrogenated silicone oil and nano-graphene powder are dispersed at high speed for 20 minutes, xylene and platinum catalyst are added, and the mixture is filtered 2-3 times using a filter element with a pore size of 10μm-60μm. The filtrate obtained is stirred evenly and then coated on a fluoroplastic film, placed in a constant temperature oven at 150°C, and cured for 10 minutes to obtain a silicone gel.

[0116] Example 2

[0117] In a first aspect, the present embodiment provides a silicone gel, wherein the raw materials, measured by weight, include:

[0118] Modified polyborosiloxane, vinyl-terminated silicone rubber, MDQ silicone resin, diluent, first catalyst, hydrogenated silicone oil, thermal conductive filler, second catalyst, reaction inhibitor, specific usage ratios can be referred to Table 1 and Table 2.

[0119] Among them, the molecular weight of vinyl-terminated methyl vinyl silicone rubber is 600,000, and the vinyl content accounts for 0.07% of the total content; the molecular weight of MDQ silicone resin is 6000, the mass ratio of M:D:Q is 0.8:2:1, and the hydroxyl content accounts for 0.1%-1% of the total mass; the platinum content of the platinum catalyst is 4000ppm; the hydrogen content of hydrogen-containing silicone oil is 0.8wt%, and the number of active hydrogen in a single molecule is greater than or equal to 3; the single layer thickness of nanographene powder is 50nm.

[0120] A second aspect of the present embodiment provides a method for preparing a silicone gel, comprising:

[0121] S1: Add modified polyborosiloxane, vinyl-terminated methyl vinyl silicone rubber, MDQ silicone resin and toluene into a reactor, heat to 80°C, stir for 40 minutes to dissolve the above raw materials, then add the first catalyst triethylamine, heat to 110°C and reflux for 4 hours. After the reaction is completed, heat to 130°C and dehumidify for 0.5 hours in a vacuum environment of -0.09MPa, and cool to obtain the base material;

[0122] S2: After the base material, 2-methyl-3-butyne-2-ol, hydrogenated silicone oil and nano-graphene powder are dispersed at high speed for 20 minutes, xylene and platinum catalyst are added, and the mixture is filtered 2-3 times using a filter element with a pore size of 10μm-60μm. The filtrate obtained is stirred evenly and then coated on a fluoroplastic film, placed in a constant temperature oven at 150°C, and cured for 10 minutes to obtain a silicone gel.

[0123] Example 3

[0124] This embodiment provides a silicone gel and a preparation method thereof, which is different from Embodiment 2 in that: the modified polyborosiloxane in this embodiment is 150 g, the vinyl-terminated methyl vinyl silicone rubber is 150 g, and other conditions are the same.

[0125] Example 4

[0126] This embodiment provides a silicone gel and a preparation method thereof, which is different from Embodiment 2 in that: the MDQ silicone resin in this embodiment is 450 g, the diluent is an alkane oil with a boiling point of 110° C.-130° C., and other conditions are the same.

[0127] Example 5

[0128] This embodiment provides a silicone gel and a preparation method thereof, which is different from Embodiment 2 in that: the MDQ silicone resin in this embodiment is 520 g, the first catalyst is benzoic acid, and other conditions are the same.

[0129] Example 6

[0130] This embodiment provides a silicone gel and a preparation method thereof, which is different from Embodiment 2 in that the hydroxyl content in the hydrogenated silicone oil of this embodiment accounts for 0.4% of the total mass, the dosage is 0.9 g, and other conditions are the same.

[0131] Example 7

[0132] This embodiment provides a silica gel and a preparation method thereof, which is different from Embodiment 2 in that the nanographene powder in this embodiment is 20 g, and other conditions are the same.

[0133] Example 8

[0134] This embodiment provides a silicone gel and a preparation method thereof, which is different from Embodiment 2 in that the hydroxyl content in the hydrogenated silicone oil of this embodiment accounts for 0.4% of the total mass, the dosage is 0.2 g, and other conditions are the same.

[0135] Example 9

[0136] This embodiment provides a silica gel and a preparation method thereof, which is different from Embodiment 2 in that the platinum content of the platinum catalyst in this embodiment is 5000 ppm, the dosage is 0.4 g, and other conditions are the same.

[0137] Example 10

[0138] This embodiment provides a silica gel and a preparation method thereof, which is different from Embodiment 2 in that the nanographene powder in this embodiment is 20 g, and other conditions are the same.

[0139] Comparative Example 1

[0140] This comparative example provides a silicone gel and a preparation method thereof, which is different from Example 2 in that: this comparative example does not add polyboron-modified siloxane, and other conditions are the same.

[0141] Comparative Example 2

[0142] This comparative example provides a silicone gel and a preparation method thereof, which is different from Example 2 in that this comparative example uses MQ silicone resin with an M / Q of 0.8 instead of MDQ silicone resin, and other conditions are the same.

[0143] Comparative Example 3

[0144] This comparative example provides a silica gel and a preparation method thereof, which is different from Example 2 in that the amount of nanographene powder in this comparative example is 10 g, and other conditions are the same.

[0145] MQ silicone resin with an M / Q of 0.8 was used instead of MDQ silicone resin, and other conditions were the same.

[0146] Comparative Example 4

[0147] This comparative example provides a silicone gel and a preparation method thereof, which is different from Example 2 in that: this comparative example does not add vinyl-terminated silicone rubber, and other conditions are the same.

[0148] Comparative Example 5

[0149] This comparative example provides a silicone gel and a preparation method thereof, which is different from Example 2 in that no thermal conductive filler is added in this comparative example, and other conditions are the same.

[0150] The feed ratios of the base materials of the above-mentioned Examples 1-10 and Comparative Examples 1-5 are shown in Table 1.

[0151] The feeding ratios of the silicone gels of the above Examples 1-10 and Comparative Examples 1-5 are shown in Table 2, where one portion of the base material is 1 g.

[0152] Table 1 Feed ratio of base material

[0153]

[0154]

[0155] Table 2 Silicone gel feed ratio

[0156]

[0157] Various properties of the silicone gels provided in Examples 1-10 and Comparative Examples 1-3 were tested, and the specific test results are shown in Table 3.

[0158] Thermal conductivity: The thermal conductivity of silicone gel is tested according to the standard of ASTM D5470-2017.

[0159] Peel strength: Test according to GB / T 2792-2014 "Test method for peel strength of adhesive tapes". Cut the sample strip to a width of 25 mm, tear off the release film on the composite film surface and stick the 50μm PET original film for reinforcement, and stick the other side to the SUS standard test plate to test the 180° peel strength of the tape.

[0160] Tensile strength and elongation at break: refer to GB / T 30776-2014 "Test method for tensile strength and elongation at break of adhesive tapes". The samples are made into 1mm thick strips, clamped on a universal tensile testing machine, and tensile tested at a speed of 120mm / min until they break. The tensile strength is the strength value corresponding to the maximum force before fracture, and the elongation at break is the ratio of the maximum stroke to the initial length of the material.

[0161] High temperature holding power: Tested in accordance with GB / T 4851-2014 "Test method for holding adhesiveness of adhesive tapes".

[0162] Anti-buffering: First test the blank value, and drop a 12g steel ball from a height of 55mm vertically onto the sensor, record the maximum force F0, test 10 times, remove the highest and lowest values ​​and take the average value; then tear off the release film of the product, stick one side on a 35μm copper foil, and the other side on a stainless steel sensor, drop a 12g steel ball from a height of 55mm vertically onto the sensor, record the maximum force F1, test 10 times, remove the highest and lowest values ​​and take the average value; impact absorption rate = (F0-F1) / F0*100%.

[0163] Volume resistivity: Refer to GB / T 40719-2021 "Determination of volume and / or surface resistivity of vulcanized rubber or thermoplastic rubber". The larger the volume resistivity value, the better the insulation performance of the material, and vice versa. If the volume resistivity value exceeds 1.0×1013Ω·m, it can be considered that the material has no conductivity.

[0164] Table 3 Performance test

[0165]

[0166]

[0167] By comparing the test results of Examples 1-10 and Comparative Example 1, it can be clearly found that the silicone gel prepared by the technical solution of the present application has significantly improved impact resistance because, compared with Comparative Example 1, we introduced modified polyborosiloxane, in which the reversible dynamic high-energy BO bond can quickly absorb energy when subjected to high-speed impact, which can significantly improve the impact resistance;

[0168] By comparing the test results of Examples 1-10 and Comparative Example 2, it can be clearly found that the silicone gel prepared by the technical solution of the present application has a slight decrease in peeling force, but can significantly improve the impact resistance and elongation. This is because compared with Comparative Example 2, the MDQ type resin is used as a tackifying component. Due to the introduction of the D link, while ensuring the pressure sensitivity, the flexibility of the resin is also improved, which can significantly improve the impact resistance.

[0169] By comparing the test results of Examples 1-10 and Comparative Example 3, although Comparative Example 3 has better impact resistance and higher peel force, its antistatic properties and thermal conductivity are relatively poor. This is mainly because compared with Comparative Example 3, by adding nanographene as a filler, the cured silicone gel has better impact resistance, as well as good thermal conductivity and antistatic properties.

[0170] The test results of Examples 1-10 and Comparative Example 4 are compared; after curing, the comparative example 4 obtains a semi-solid state without a fixed shape, and the performance cannot be tested.

[0171] By comparing the test results of Examples 1-10 and Comparative Example 5, although Comparative Example 5 has better impact resistance and higher peel force, its antistatic properties and thermal conductivity are relatively poor. This is mainly because compared with Comparative Example 5, by adding nanographene as a filler, the cured silicone gel has better impact resistance, as well as good thermal conductivity and antistatic properties.

[0172] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

[0173] In addition, those skilled in the art will appreciate that, although some embodiments herein include certain features included in other embodiments but not other features, the combination of features of different embodiments is meant to be within the scope of the present application and form different embodiments. For example, in the above claims, any one of the claimed embodiments may be used in any combination. The information disclosed in this background technology section is intended only to deepen the understanding of the overall background technology of the present application and should not be regarded as an admission or in any form of implication that the information constitutes prior art known to those skilled in the art.

Claims

1. A silicone gel, characterized in that: The raw materials include, by weight: 30-100 parts of modified polyborosiloxane, 100-200 parts of vinyl-terminated silicone rubber, 300-1000 parts of MDQ silicone resin, 350-1100 parts of diluent, 0.5-5 parts of first catalyst, 1.5-25 parts of hydrogenated silicone oil, 80-600 parts of thermal conductive filler, 3-20 parts of second catalyst, 0.3-3 parts of reaction inhibitor; The first catalyst includes an acidic catalyst and / or a basic catalyst; The second catalyst includes a platinum catalyst.

2. The silicone gel according to claim 1, characterized in that: At least one of the following conditions is met: A. The modified polyborosiloxane is prepared by high-temperature condensation of vinyl hydroxy silicone oil and boric acid compounds; The boric acid compound includes boric acid and / or borate ester compound; B. The molecular weight of the vinyl terminated silicone rubber is 500,000-900,000; C. The vinyl content in the vinyl terminated silicone rubber accounts for 0.04% to 0.4% of the total content.

3. The silicone gel according to claim 1, characterized in that: At least one of the following conditions is met: A. The molecular weight of the MDQ silicone resin is 5000-10000; B. The molar ratio of M:D:Q in the MDQ silicone resin is (0.5-1):(1-3):1; C. The hydroxyl content in the MDQ silicone resin accounts for 0.1%-1% of the total mass.

4. The silicone gel according to claim 1, characterized in that: At least one of the following conditions is met: A. The diluent includes one or more of toluene, xylene, trimethylbenzene, and alkane solvents; B. The thermally conductive filler includes nanographene; C. The reaction inhibitor includes one or more of acetylene cyclohexanol, 2-methyl-3-butyn-2-ol, and 1-(1-propynyl)cyclohexanol.

5. The silicone gel according to claim 1, characterized in that: The platinum content of the platinum catalyst is 3000ppm-5000ppm.

6. The silicone gel according to any one of claims 1 to 5, characterized in that: At least one of the following conditions is met: A. The hydrogen content of the hydrogen-containing silicone oil is 0.3wt%-1.5wt%; B. The number of active hydrogen atoms in a single molecule of the hydrogen-containing silicone oil is greater than or equal to 3.

7. A method for preparing the silicone gel according to any one of claims 1 to 6, characterized in that: include: The raw materials are mixed to obtain the silica gel.

8. The method for preparing silicone gel according to claim 7, characterized in that: The mixing includes: The modified polyborosiloxane, the vinyl-terminated silicone rubber, the MDQ silicone resin, and the diluent are first mixed to obtain a first mixed material; Performing a second mixing of the first mixed material and the first catalyst to obtain a second mixed material, and performing a first heat treatment on the second mixed material to obtain a base material; The base material, the hydrogen-containing silicone oil, the thermal conductive filler, the diluent, the second catalyst and the inhibitor are mixed for the third time to obtain a third mixture, and the third mixture is subjected to solid-liquid separation and a second heat treatment to obtain the silicone gel.

9. The method for preparing silicone gel according to claim 8, characterized in that: At least one of the following conditions is met: A. The first mixing time is 30min-60min, and the temperature is 60℃-100℃; B. The temperature of the first heat treatment is 110°C-130°C, and the time is 3h-5h; C. After the first heat treatment, vacuum treatment is performed to obtain the base material, the vacuum treatment time is 20min-40min, the temperature is 120°C-140°C, and the vacuum degree is -0.05MPa--0.1MPa; D. The pore size of the solid-liquid separation is 10 μm-60 μm; E. The temperature of the second heat treatment is 100°C-150°C, and the time is 5min-15min.

10. An electronic product, characterized in that: The invention relates to a silicone gel comprising the silicone gel according to any one of claims 1 to 7 or the silicone gel prepared by the method for preparing the silicone gel according to claim 8 or 9.

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