Modified hydrogen-containing silicone oil, single-component heat-conducting gel and preparation method of single-component heat-conducting gel

Abstract

The invention discloses modified hydrogen-containing silicone oil and single-component heat-conducting gel prepared from the modified hydrogen-containing silicone oil. According to the method for preparing the single-component heat-conducting gel, starting from the modified hydrogen-containing silicone oil and the powder treating agent, the hydrogen-containing silicone oil with long-chain alkyl and the powder treating agent are organically matched with other components, and the obtained single-component heat-conducting gel not only can effectively improve the extrudability, but also can be used for preparing the single-component heat-conducting gel. Moreover, the thermal resistance is not obviously increased in the long-term use process in a high-temperature environment, the phenomena of pulverization and hardening do not occur in high-temperature aging, and the thermal stability of the heat-conducting gel can be effectively improved; therefore, the service life and the period of an electronic component using the heat-conducting gel can be greatly prolonged and prolonged.

Description

Technical Field

[0001] The invention relates to the technical field of polymer materials, in particular to thermal conductive gel, and in particular to modified hydrogen-containing silicone oil, single-component thermal conductive gel and a preparation method thereof. Background Art

[0002] In recent years, with the rapid development of new energy vehicles, 5G communications, smart phones and laptops, heat dissipation has gradually become a focus of attention. At present, silicone thermal conductive gel, thermal conductive silicone grease and thermal conductive gasket have been widely used. Among them, silicone thermal conductive gel can be divided into single component and two components. The single component is similar to thermal conductive mud and thermal conductive silicone grease. The two-component thermal conductive gel is similar to the elastomer of thermal conductive gasket after curing. Thermal conductive gel is mainly composed of vinyl silicone oil and thermal conductive powder. The thermal conductive powder mainly includes aluminum oxide, zinc oxide, aluminum hydroxide, boron nitride and other substances. At present, there are many requirements for the performance of single-component thermal conductive gel, among which high extrusion, low oil permeability and good temperature resistance are several main core properties. It is difficult to take into account several properties at the same time. Although ordinary long-chain alkyl treatment agents can meet the requirements of extrusion, they are easy to powder and harden during long-term high-temperature aging, and the temperature resistance is relatively poor. Therefore, how to prepare a thermal conductive gel that can meet high extrusion, low oil permeability and good temperature resistance has become more and more the focus of market attention.

[0003] CN118879080 A discloses a thermally conductive gel with low oil permeability and high thermal conductivity and its preparation process, wherein the powder and silicone oil form a good combination through a composite coupling agent, thereby achieving higher powder filling and low oil permeability after curing. However, this technology does not focus on the thermal resistance change and powdering of the thermally conductive gel under high temperature aging.

[0004] CN118146770 A discloses a low oil separation interface thermal conductive gel and a preparation method thereof. The preparation of the low oil separation thermal conductive gel is achieved through a two-step method. The preform can minimize the oil separation of the silicone oil in the gel to ensure that the vinyl silicone oil and the hydrogen-containing silicone oil react to the maximum extent. Then, some diluents are added to ensure the extrusion rate of the low oil separation thermal conductive gel. However, although this technology achieves high extrusion and low oil penetration, it does not study the temperature resistance.

[0005] The increase in the hardness and thermal resistance of the thermal conductive gel is mainly related to the powder treating agent. Although the ordinary long-chain alkyl treating agent can ensure the extrusion of the powder, it is easy to crack in the long-term high-temperature use environment, and the hardness and thermal resistance both increase significantly. In particular, the increase in the thermal resistance of the thermal conductive gel will directly affect the service life of electronic components.

[0006] At present, the high thermal conductivity gel (≥5.0W) on the market is difficult to achieve high extrusion, good temperature resistance, and low oil permeability, basically sacrificing one performance to meet other performances. The development of a thermal conductive gel that can meet high extrusion, low oil permeability, and good temperature resistance is a strong demand in the current market. Summary of the invention

[0007] Based on this, the purpose of the present invention is to provide a modified hydrogenated silicone oil, a thermally conductive gel and a preparation method and application thereof, wherein the thermally conductive gel has good extrudability and oil permeability, and also good temperature resistance.

[0008] The first aspect of the present invention provides a modified hydrogen-containing silicone oil.

[0009] The modified hydrogen-containing silicone oil is produced by the reaction of D4H cyclotetrasiloxane and olefin, the structural formula of the olefin is

[0010] Wherein 20≥q≥6; Vi is vinyl.

[0011] In some embodiments, the molar ratio of D4H cyclotetrasiloxane to olefin is 1:2-4, more preferably 1:2.1-2.3.

[0012] In some of the embodiments, the modified hydrogen-containing silicone oil contains a compound of the following structural formula, wherein 20≥q≥6, q is an integer;

[0013] In some of the embodiments, the modified hydrogen-containing silicone oil is produced by reacting D4H cyclotetrasiloxane with olefins, and the reaction principle is as follows;

[0014]

[0015] Wherein 20≥q≥6; Vi is vinyl.

[0016] In some embodiments, it is preferably 20≥q≥10, more preferably 18≥q≥12, and more preferably 15≥q≥12.

[0017] In some embodiments, the modified hydrogen-containing silicone oil has a hydrogen content of 0.01wt% to 0.4wt% and a viscosity of 10 to 300mPa·s; preferably, the modified hydrogen-containing silicone oil has a hydrogen content of 0.1wt% to 0.3wt% and a viscosity of 50mPa·s to 200mPa·s, and more preferably, the modified hydrogen-containing silicone oil has a hydrogen content of 0.12wt% to 0.2wt% and a viscosity of 50mPa·s to 200mPa·s. More preferably, the modified hydrogen-containing silicone oil has a hydrogen content of 0.12wt% to 0.2wt% and a viscosity of 50mPa·s to 150Pa·s.

[0018] The preparation method of the modified hydrogen-containing silicone oil comprises the following steps:

[0019] (1) slowly dripping olefin into a reaction kettle containing D4H cyclotetrasiloxane and platinum catalyst and toluene as solvent; after dripping, continue reflux reaction at 80-100° C. for 1-3 hours;

[0020] (2) performing reduced pressure distillation at 80-100° C. for 1-2 hours to remove unreacted small molecules and solvents, remove the catalyst, and obtain modified hydrogen-containing silicone oil.

[0021] In some embodiments, the molar ratio of D4H cyclotetrasiloxane to olefin is 1:2-4:, preferably 1:2.1-2.3.

[0022] The second object of the present invention is to provide a single-component thermally conductive gel, which is prepared from the following raw material components in parts by weight:

[0023] 30-60 parts of vinyl-terminated silicone oil;

[0024] 30-60 parts of single-ended vinyl silicone oil;

[0025] 5-15 parts of powder treatment agent;

[0026] Platinum catalyst 5-15ppm;

[0027] 10-30 parts of any of the above modified hydrogen-containing silicone oils;

[0028] Inhibitor 0.01-0.2 parts;

[0029] Thermal conductive powder 1000-3000 parts;

[0030] The powder treatment agent is prepared by hydrosilylation reaction of D4H cyclotetrasiloxane with vinyl silane, olefin and phenyl vinyl silane respectively;

[0031] The vinyl silane structure is as follows:

[0032] Vi-Si-(OR1)3

[0033] Wherein OR1 is one or more of methoxy, ethoxy, formyloxy, and acetoxy, and Vi is vinyl; the olefin structure is as follows:

[0034]

[0035] Wherein 20≥q≥6, Vi is vinyl.

[0036] In some embodiments, it is preferably 20≥q≥10, more preferably 18≥q≥12, and even more preferably 15≥q≥12.

[0037] In some of the embodiments, the powder treating agent contains a compound with the following structure:

[0038]

[0039] wherein 20≥q≥6, q is an integer; the substituent OR1 is methoxy, ethoxy, formyloxy or acetoxy. Preferably, 20≥q≥10, more preferably 18≥q≥12, more preferably 15≥q≥12.

[0040] In some embodiments, the single-component thermally conductive gel is prepared from the following raw material components in parts by weight:

[0041] 40-50 parts of vinyl-terminated silicone oil;

[0042] 40-50 parts of single-ended vinyl silicone oil;

[0043] 5-10 parts of powder treatment agent;

[0044] Platinum catalyst 5-10ppm;

[0045] 10-20 parts of any of the above modified hydrogen-containing silicone oils;

[0046] Inhibitor 0.05-0.1 part;

[0047] Thermal conductive powder 1500-2500 parts.

[0048] It is further preferred that the modified hydrogen-containing silicone oil is 10-15 parts, and / or the powder treatment agent is 5-10 parts, or preferably the powder treatment agent is 5-8 parts.

[0049] In some of the embodiments, the viscosity of the vinyl-terminated silicone oil is 50-1000cp, and the vinyl content is 0.1% to 2wt%; further preferred is the vinyl-terminated silicone oil with a viscosity of 100-500cp and a vinyl content of 0.1% to 1wt%, and more preferred is the vinyl-terminated silicone oil with a viscosity of 100-200cp and a vinyl content of 0.5% to 1wt%.

[0050] In some embodiments, the single-ended vinyl silicone oil has a viscosity of 50-1000cp and a vinyl content of 0.05% to 1wt%; preferably, the single-ended vinyl silicone oil has a viscosity of 100-500cp and a vinyl content of 0.05% to 0.5wt%, and more preferably, the single-ended vinyl silicone oil has a viscosity of 100-300cp and a vinyl content of 0.1% to 0.5wt%.

[0051] In some of the embodiments, the thermally conductive powder is a spherical powder selected from one or more of aluminum oxide, aluminum nitride, magnesium oxide, zinc oxide or boron nitride, preferably spherical aluminum oxide or quasi-spherical aluminum oxide, and the particle size of the thermally conductive powder is 1 to 100 um.

[0052] More preferably, spherical alumina or quasi-spherical alumina is a thermally conductive powder with a particle size of 1 to 50 um, preferably a thermally conductive powder with a particle size of 20 to 30 um.

[0053] In some embodiments, the platinum catalyst is one of chloroplatinic acid, chloroplatinic acid-isopropanol complex, chloroplatinic acid-divinyltetramethyldisiloxane complex or a combination thereof.

[0054] In some embodiments, the inhibitor is one of 1-ethynyl-1-cyclohexanol, tetramethyltetravinylcyclotetrasiloxane, 2-methyl-3-butynyl-2-ol, 3-methyl-1-ethynyl-3-ol, 3,5-dimethyl-1-hexynyl-3-ol, 3-methyl-1-dodecyn-3-ol, or a combination thereof.

[0055] In some embodiments, the method for preparing the powder treatment agent comprises the following steps:

[0056] (1) slowly dripping vinyl silane into a reaction kettle containing D4H cyclotetrasiloxane, a platinum catalyst and a toluene solvent, and continuing the reflux reaction for 1-3 hours after the dripping is completed to obtain a mixed solution;

[0057] (2) slowly dripping olefin into the above mixed solution, and after dripping, heating to 80-100°C and reflux for 1-3 hours;

[0058] (3) slowly dripping phenylvinylsilane, continuing the reflux reaction at 80-100° C. for 1-3 hours after dripping, and then distilling under reduced pressure for about 1-2 hours to remove unreacted small molecules and solvents, and remove the catalyst to obtain the powder treatment agent;

[0059] The vinyl silane structure is as follows: Vi-Si-(OR1)3, wherein OR1 is one or more of methoxy, ethoxy, formyloxy, and acetoxy, and Vi is vinyl;

[0060] The olefin structure is as follows: Wherein 20≥q≥6, Vi is vinyl.

[0061] In some embodiments, the molar ratio of the vinyl silane to the D4H cyclotetrasiloxane is 1.-1.3:1.

[0062] In some embodiments, the molar ratio of the olefin to D4H cyclotetrasiloxane is 1-1.2:1.

[0063] In some embodiments, the molar ratio of phenylvinylsilane to D4H cyclotetrasiloxane is 1-1.3:1.

[0064] The method for preparing the single-component thermally conductive gel comprises the following steps:

[0065] (1) Add the vinyl-terminated silicone oil, the single-terminated silicone oil and the powder treatment agent into a planetary mixer and stir for 5-15 minutes until they are evenly mixed. Then add the thermal conductive powder and stir for 10-30 minutes until the mixture is evenly mixed.

[0066] (2) heating to about 100-120°C, stopping stirring, maintaining vacuum for 60-120 minutes, and then cooling to room temperature;

[0067] (3) After adding inhibitors, hydrogen-containing silicone oil, etc. and stirring for about 15-30 minutes, a platinum catalyst is added and vacuum stirring is continued for about 15-30 minutes, and then the temperature is raised to 80° C.-100° C. and cured for 60-120 minutes to obtain the thermal conductive gel.

[0068] When preparing the thermally conductive gel, the present invention starts from the modified hydrogen-containing silicone oil and the powder treatment agent to prepare the hydrogen-containing silicone oil and the powder treatment agent with a long-chain alkyl group, and the two are organically matched with other components. The obtained single-component thermally conductive gel can not only effectively improve the extrusion performance, but also has no obvious increase in thermal resistance during long-term use in a high-temperature environment, and no powdering and hardening phenomenon occurs during high-temperature aging, which can effectively improve the thermal stability of the thermally conductive gel. At the same time, the introduction of single-terminated vinyl silicone oil reduces the oil permeation rate of the system, thereby greatly improving the service life and cycle of electronic components using the thermally conductive gel of the present invention.

[0069] The present invention synthesizes a modified hydrogenated silicone oil and a new powder treatment agent for use in combination. When constructing a single-component thermally conductive gel, we found that the introduction of long-chain alkyl groups into the hydrogenated silicone oil and the introduction of phenyl groups into the powder treatment agent can effectively wet the thermally conductive powder and improve the extrusion performance. At the same time, it can also improve the temperature resistance of the treatment agent, and no degradation and volatilization will occur under high-temperature aging conditions, ensuring that the thermal resistance does not increase significantly, and no powdering and hardening will occur. The alkoxy group can effectively treat the surface of the powder; this may be because the powder treatment agent contains a single silicon hydrogen group, and the group position is at the outermost end of the molecule, which is easy to react, avoiding problems such as curing and hardening due to steric hindrance, and can participate in the cross-linking reaction of the system, enhance the bonding force between the silicone oil and the powder, and reduce the oil permeability after curing. In addition, the long-chain alkyl group can more effectively wet the thermally conductive powder and improve the extrusion performance. At the same time, we use single-end vinyl silicone oil, which can effectively reduce the vinyl content of the system and thus reduce the oil permeability. The thermal conductive gel thus obtained has high extrusion properties, low oil permeability, and excellent thermal stability. During long-term high-temperature aging, the thermal resistance does not increase significantly, it does not powder or harden, and has high application stability. DETAILED DESCRIPTION

[0070] The technical scheme of the present invention is further illustrated by specific examples below. Those skilled in the art should understand that the examples are only to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0071] 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 of the present invention. 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.

[0072] The terms "including" and "having" and any variations thereof of the present invention are intended to cover non-exclusive inclusions. For example, a process, method, device, product or equipment comprising a series of steps is not limited to the listed steps or modules, but may optionally include steps not listed, or may optionally include other steps inherent to these processes, methods, products or equipment.

[0073] In the present invention, the term "multiple" refers to two or more than two. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent the following three situations: A exists alone, A and B exist at the same time, and B exists alone. The character " / " generally indicates that the associated objects are in an "or" relationship.

[0074] Some embodiments of the present invention involve

[0075] The following are specific embodiments.

[0076] The viscosity in the following examples refers to the viscosity at 25° C. unless otherwise specified; the “parts” mentioned refer to parts by weight unless otherwise specified.

[0077] 1. The preparation method of the modified hydrogen-containing silicone oil used in the following examples is as follows.

[0078] The preparation method of the modified hydrogen-containing silicone oil comprises the following steps:

[0079] (1) Add an appropriate amount of D4H cyclotetrasiloxane (1,3,5,7-tetramethylcyclotetrasiloxane) and 3-5 ppm (based on Pt content) of Custer platinum catalyst to a reaction kettle equipped with a stirrer, a reflux condenser, a dropping funnel and a thermometer, and stir evenly with solvent toluene;

[0080] (2) slowly dropping 1-hexadecene into the above mixed solution; after the dropping is completed, the reaction is continued under reflux at 80° C. for 2 h, wherein the molar ratio of the 1-hexadecene to the D4H cyclotetrasiloxane is 2.2:1;

[0081] (3) performing reduced pressure distillation at 80° C. for about 1 hour to remove unreacted small molecules and solvents, and removing the catalyst by activated carbon adsorption to obtain modified hydrogen-containing silicone oil.

[0082] It was determined that the viscosity of the modified hydrogen-containing silicone oil was about 100 cp and the hydrogen content was 0.16 wt%.

[0083] The modified hydrogen-containing silicone oil includes a compound of the following structural formula:

[0084]

[0085] The reaction principle of the modified hydrogen-containing silicone oil is as follows:

[0086] Among them, q = 13. The infrared detection showed that the Si-H stretching vibration peak of the product still existed at 2162cm-1, where the Si-H characteristic absorption peak was located, and there was no C=C stretching vibration peak at 1643cm-1, which proved that the olefin had been basically reacted, and the symmetric stretching vibration peak of -CH2 appeared near 2860cm-1, and the CH bending vibration absorption peak in -CH2- was at 1372cm-1.

[0087] 2. The preparation method of the powder treatment agent used in the following examples is as follows.

[0088] The preparation method of the powder treatment agent comprises the following steps:

[0089] (1) D4H cyclotetrasiloxane and 3-5 ppm (based on Pt content) of platinum catalyst (Castells catalyst) were first added to a reaction kettle equipped with a stirrer, a reflux condenser, a dropping funnel and a thermometer, and stirred evenly;

[0090] (2) slowly dripping vinyl triacetoxysilane into the reaction kettle, and continuing the reflux reaction for 2 hours after the dripping is completed, wherein the molar ratio of the vinyl triacetoxysilane to D4H cyclotetrasiloxane is 1:1;

[0091] (3) slowly adding 1-hexadecene to the mixed solution, and after the addition is complete, heating to 80° C. and reflux for 2 h, wherein the molar ratio of 1-hexadecene to D4H-cyclotetrasiloxane is 1:1;

[0092] (4) Slowly drip phenylvinylsilane into the reactor, and continue to reflux for 2 hours after dripping. The molar ratio of phenylvinylsilane to D4H is 1:1. Then, vacuum distillation is performed at 80° C. for about 1 hour to remove unreacted small molecules and solvents, and the catalyst is removed by activated carbon adsorption to obtain a homemade powder treatment agent.

[0093] The powder treatment agent includes the following structure:

[0094]

[0095] Wherein, q=13; OR1 is an acetoxy group.

[0096] After infrared detection, Si-H characteristic absorption peak still appeared at 2160cm-1, and the product was at 1642.23cm -1 There is no C=C absorption peak at 2860cm -1 The symmetrical stretching vibration peak of -CH2 appears near 1370cm -1 The absorption peak of CH bending vibration in -CH2- appears at 1590cm -1 and 1460cm -1 The characteristic peak of benzene ring appears at 1075cm -1 and 1090cm -1 The stretching vibration absorption peak of Si-OC appears nearby.

[0097] 3. The preparation of the thermally conductive gel used in the following examples can be carried out according to the following method.

[0098] The method for preparing the single-component thermally conductive gel comprises the following steps:

[0099] (1) Add the vinyl silicone oil (including vinyl-terminated silicone oil and / or single-terminated silicone oil) and the powder treatment agent into a planetary mixer, stir for 10 minutes to make them uniform, then add the thermal conductive powder, and stir for 15 minutes after adding until they are uniformly mixed;

[0100] (2) heating to 100-105°C and stopping stirring, maintaining vacuum for 110-120 minutes and then cooling to room temperature;

[0101] (3) After adding the inhibitor and the modified hydrogen-containing silicone oil and stirring for about 15 minutes, the platinum catalyst is added and the vacuum stirring is continued for about 15-20 minutes, and then the temperature is raised to 80° C.-85° C. and cured for 110 minutes-120 minutes to obtain the thermal conductive gel.

[0102] Example 1

[0103] The single-component thermally conductive gel prepared in this embodiment has the following raw material composition:

[0104]

[0105] Example 2

[0106] The single-component thermally conductive gel prepared in this embodiment has the following raw material composition:

[0107]

[0108]

[0109] Example 3

[0110] The single-component thermally conductive gel prepared in this embodiment has the following raw material composition:

[0111]

[0112] Example 4

[0113] The single-component thermally conductive gel prepared in this embodiment has the following raw material composition:

[0114]

[0115]

[0116] Example 5

[0117] The single-component thermally conductive gel prepared in this embodiment has the following raw material composition:

[0118]

[0119] Comparative Example 1

[0120] The single-component thermally conductive gel prepared in this embodiment has the following raw material composition:

[0121]

[0122]

[0123] Comparative Example 2

[0124] The single-component thermally conductive gel prepared in this embodiment has the following raw material composition:

[0125]

[0126] Comparative Example 3

[0127] The single-component thermally conductive gel prepared in this embodiment has the following raw material composition:

[0128]

[0129]

[0130] Comparative Example 4

[0131] The single-component thermally conductive gel prepared in this embodiment has the following raw material composition:

[0132]

[0133] Comparative Example 5

[0134] The single-component thermally conductive gel prepared in this embodiment has the following raw material composition:

[0135]

[0136]

[0137] Comparative Example 6

[0138] The single-component thermally conductive gel prepared in this embodiment has the following raw material composition:

[0139]

[0140] The above thermally conductive gels were tested separately:

[0141] 1. Thermal resistance: measured in accordance with "ASTM D 5470-01 Characterization test for testing the thermal conductivity properties of thin thermally conductive solid electrical insulating materials" (2 pieces of 3mm thick alumina fixtures, glue layer thickness 0.5mm) Unit: ℃*in 2 / W.

[0142] 2. Heat aging resistance: The heat aging condition is 150℃ / 1000h, and observe whether it becomes hard and powdery.

[0143] 3. Extrusion test: The gel was loaded into a 30cc single-component rubber tube, vacuumed and centrifuged to remove bubbles. Under a pressure of 90 psi, the quality of the extruded gel was tested within 60 seconds by the extruder (the inner diameter of the extruder was 2.5 mm).

[0144] 4. Oil permeability test: Take 10g of single-component thermal conductive gel, place it on filter paper, and spread it into a circular gel sample with a diameter of 3cm. After baking at 120℃ for 7 days, calculate the oil permeation area (maximum area of ​​oil permeation edge - area of ​​circular gel sample).

[0145]

[0146] It can be seen from the table that the self-made powder treatment agent and the thermal conductive gel of modified hydrogenated silicone oil used in Examples 1-5 have excellent extrudability and oil permeability, and the thermal resistance does not increase much during baking at 150°C for 1000h.

[0147] The increase in thermal resistance in Examples 1-5 is also basically maintained within 10%. In Comparative Examples 3 and 4, long-chain coupling agent hexadecyltrimethoxysilane is used. Even when used in combination with our modified hydrogen-containing silicone oil, its temperature resistance is still poor. The thermal resistance increases significantly by more than 20% during the aging process, and powdering and hardening occur. After analysis, this may be because the powder treatment agent prepared by us contains phenyl groups, and there are hydrogen-containing groups that can participate in the reaction to increase the cross-linking density, which can further improve the temperature resistance of the treatment agent. The thermal resistance of the thermally conductive gel will not increase significantly during long-term high-temperature aging. In addition, due to the presence of hydrogen-containing groups, participating in the system reaction, the oil permeability will be reduced to a certain extent. In addition, the presence of long-chain alkyl groups also ensures the extrusion of the treatment agent.

[0148] It can be seen from the comparative example 1 that all double-ended vinyl silicone oils are used, that its oil permeation rate is significantly lower than that of the example 1 containing single-ended vinyl silicone oil. This may be because if the single-ended vinyl silicone oil will reduce the vinyl content of the system, usually the vinyl content in the single-component thermal conductive gel silicone oil system is excessive, which will result in too much vinyl silicone oil not participating in the reaction, and oil permeation will occur in a long-term high-temperature use environment.

[0149] It can be seen from Comparative Example 2 that the extrusion performance when the modified hydrogen-containing silicone oil described in the present invention is not used is significantly decreased compared with Example 1. The introduction of long-chain alkyl groups into the modified hydrogen-containing silicone oil described in the present invention can significantly enhance the wettability of the powder, thereby improving the extrusion performance.

[0150] It can be seen from Comparative Example 5 that although the extrusion performance of the one-component thermal conductive gel is still very good when the amount of the modified hydrogen-containing silicone oil reaches 10 parts and is used in combination with 5-10 parts of the powder treatment agent, when the amount of the modified hydrogen-containing silicone oil is only 8 parts, the extrusion performance is significantly reduced.

[0151] It can be seen from Comparative Example 6 that when the dosage of the powder treatment agent is increased to 18 parts, the extrusion performance decreases. This may be because the hydrogen-containing groups in the powder treatment agent participate in the cross-linking reaction of the system in large quantities, which increases the cross-linking density of the silicone oil and reduces the oil penetration area.

[0152] The present invention starts from the system and structural design, uses single-end vinyl silicone oil to reduce the oil permeability of the system, improves the extrusion performance by modifying the hydrogen-containing silicone oil, and designs a suitable powder treatment agent to prepare a single-component thermal conductive gel that can improve the temperature resistance and oil permeability while ensuring the extrusion performance.

[0153] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described 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.

[0154] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A modified hydrogen-containing silicone oil, characterized in that: The modified hydrogen-containing silicone oil is produced by the reaction of D4H cyclotetrasiloxane and olefin, the structural formula of the olefin is Wherein 20≥q≥6; Vi is vinyl, preferably, the molar ratio of the D4H cyclotetrasiloxane to the olefin is 1:2-4, more preferably 1:2.1-2.

3.

2. The modified hydrogenated silicone oil according to claim 1, characterized in that The modified hydrogen-containing silicone oil contains a compound of the following structural formula: Wherein 20≥q≥6, q is an integer; preferably 20≥q≥10, more preferably 18≥q≥12, and more preferably 15≥q≥12.

3. The modified hydrogenated silicone oil according to claim 1 or 2, characterized in that: The modified hydrogen-containing silicone oil has a hydrogen content of 0.01wt% to 0.4wt% and a viscosity of 10 to 300mPa·s; preferably, it is a modified hydrogen silicone oil with a hydrogen content of 0.1wt% to 0.3wt% and a viscosity of 50mPa·s to 200mPa·s, and further preferably, it is a modified hydrogen silicone oil with a hydrogen content of 0.12wt% to 0.2wt% and a viscosity of 50mPa·s to 150mPa·s.

4. A method for preparing the modified hydrogenated silicone oil according to any one of claims 1 to 3, characterized in that: The following steps are involved: (1) slowly dripping olefin into a reaction kettle containing D4H cyclotetrasiloxane and platinum catalyst and toluene as solvent; after dripping, continue reflux reaction at 80-100° C. for 1-3 hours; (2) performing reduced pressure distillation at 80-100° C. for 1-2 h to remove unreacted small molecules and solvents, remove the catalyst, and obtain modified hydrogen-containing silicone oil; Preferably, the molar ratio of D4H cyclotetrasiloxane to olefin is 1:2-4, more preferably 1: 2.1-2.3。 5. A single-component thermally conductive gel, characterized in that: It is prepared from the following raw material components in parts by weight: 30-60 parts of vinyl-terminated silicone oil; 30-60 parts of single-ended vinyl silicone oil; 5-15 parts of powder treatment agent; Platinum catalyst 5-15ppm; 10-30 parts of the modified hydrogen-containing silicone oil according to any one of claims 1 to 3; Inhibitor 0.01-0.2 parts; Thermal conductive powder 1000-3000 parts; The powder treatment agent is prepared by hydrosilylation reaction of D4H cyclotetrasiloxane with vinyl silane, olefin and phenyl vinyl silane respectively; The vinyl silane structure is as follows: Vi-Si-(OR1)3 Wherein OR1 is one or more of methoxy, ethoxy, formyloxy, and acetoxy, and Vi is vinyl; the olefin structure is as follows: Wherein 20≥q≥6, Vi is vinyl.

6. The one-component thermally conductive gel according to claim 5, characterized in that: It is prepared from the following raw material components in parts by weight: 40-50 parts of vinyl-terminated silicone oil; 40-50 parts of single-ended vinyl silicone oil; 5-10 parts of powder treatment agent; Platinum catalyst 5-10ppm; 10-20 parts of the modified hydrogen-containing silicone oil; Inhibitor 0.05-0.1 part; Thermal conductive powder 1500-2500 parts.

7. The one-component thermally conductive gel according to claim 5, characterized in that: The vinyl-terminated silicone oil has a viscosity of 50-1000cp and a vinyl content of 0.1% to 2wt%; preferably, the vinyl-terminated silicone oil has a viscosity of 100-500cp and a vinyl content of 0.1% to 1wt%, and more preferably, the vinyl-terminated silicone oil has a viscosity of 100-200cp and a vinyl content of 0.5% to 1wt%; and / or The single-ended vinyl silicone oil has a viscosity of 50-1000cp and a vinyl content of 0.05% to 1wt%; preferably, the single-ended vinyl silicone oil has a viscosity of 100-500cp and a vinyl content of 0.05% to 0.5wt%, and more preferably, the single-ended vinyl silicone oil has a viscosity of 100-300cp and a vinyl content of 0.1% to 0.5wt%.

8. The one-component thermally conductive gel according to claim 5, characterized in that: The thermally conductive powder is a spherical powder with a particle size of 1 to 100 um, selected from one or more of aluminum oxide, aluminum nitride, magnesium oxide, zinc oxide or boron nitride, preferably spherical aluminum oxide or quasi-spherical aluminum oxide, preferably a thermally conductive powder with a particle size of 20 to 30 um; and / or The platinum catalyst is one of chloroplatinic acid, chloroplatinic acid-isopropanol complex, chloroplatinic acid-divinyltetramethyldisiloxane complex or a combination thereof; and / or The inhibitor is one of 1-ethynyl-1-cyclohexanol, tetramethyltetravinylcyclotetrasiloxane, 2-methyl-3-butynyl-2-ol, 3-methyl-1-ethynyl-3-ol, 3,5-dimethyl-1-hexynyl-3-ol, 3-methyl-1-dodecynyl-3-ol or a combination thereof.

9. The single-component thermally conductive gel according to any one of claims 5 to 8, characterized in that: The powder treatment agent contains a compound with the following structure: wherein 20≥q≥6, q is an integer; the substituent OR1 is methoxy, ethoxy, formyloxy or acetoxy; Preferably, the method for preparing the powder treating agent comprises the following steps: (1) slowly dripping vinyl silane into a reaction kettle containing D4H cyclotetrasiloxane, platinum catalyst and toluene as solvent, and continuing the reflux reaction for 1-3 hours after the dripping is completed to obtain a mixed solution; (2) slowly dripping olefin into the above mixed solution, and after the dripping is completed, heating to 80-100° C. and reflux for 1-3 hours; (3) slowly dripping phenylvinylsilane, continuing the reflux reaction at 80-100° C. for 1-3 hours after dripping, and then distilling under reduced pressure for about 1-2 hours to remove unreacted small molecules and solvents, and remove the catalyst to obtain the powder treatment agent; More preferably, the molar ratio of the vinyl silane to the D4H cyclotetrasiloxane is 1.-1.3:1; and / or The molar ratio of the olefin to the D4H cyclotetrasiloxane is 1-1.2:1; and / or The molar ratio of the phenylvinylsilane to the D4H cyclotetrasiloxane is 1-1.3:

1.

10. A method for preparing the single-component thermally conductive gel according to any one of claims 5 to 9, characterized in that: The following steps are involved: (1) Add the vinyl-terminated silicone oil, the single-terminated silicone oil, and the powder treatment agent into a blender, stir for 5-15 minutes to mix evenly, then add the thermal conductive powder in batches, stir for 10-30 minutes until the mixture is evenly mixed; (2) heating to about 100-120°C, stopping stirring, maintaining vacuum for 60-120 min, and then cooling to room temperature; (3) Add the inhibitor and the hydrogen-containing silicone oil and stir for about 15-30 minutes, then add the platinum catalyst and continue to stir in vacuum for 15-30 minutes, then heat to 80° C.-100° C. and cure for 60-120 minutes to obtain the one-component thermal conductive gel.

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