Modified MQ resin and preparation method and application thereof
阅读说明：本技术 一种改性mq树脂及其制备方法和用途 (Modified MQ resin and preparation method and application thereof ) 是由 刘志锋 封玲珑 马伟 曹骏 高源� 杨继朋 杨慧雅 王庆义 于 2020-12-02 设计创作，主要内容包括：本发明提供一种改性MQ树脂及其制备方法和用途,属于灌封胶技术领域。通过本发明方法制备的改性MQ树脂属于无溶剂型液体MQ树脂,不仅环保低VOC,而且可以简化工艺；在补强效果基本不变的情况下,具有下述优势：配胶溶解时间变短,减少溶解工艺时间,提高效率；黏度变小,增加流动性,灌封流平更充分,有利用于工艺操作；减少空间位阻减少,容易交联固化,进一步缩短工艺时间。用于灌封胶领域,能够有效的解决灌封胶的渗油问题,同时还延长了与基材的粘接寿命。(The invention provides a modified MQ resin and a preparation method and application thereof, belonging to the technical field of pouring sealants. The modified MQ resin prepared by the method belongs to solvent-free liquid MQ resin, is environment-friendly and low in VOC, and can simplify the process; under the condition that the reinforcing effect is basically unchanged, the following advantages are achieved: the time for preparing and dissolving the glue is shortened, the time for dissolving process is reduced, and the efficiency is improved; the viscosity is reduced, the fluidity is increased, the encapsulation and leveling are more sufficient, and the method is favorable for process operation; the steric hindrance is reduced, the crosslinking and curing are easy, and the process time is further shortened. The adhesive is used in the field of pouring sealant, can effectively solve the oil leakage problem of the pouring sealant, and simultaneously prolongs the bonding life with a base material.)
1. A modified MQ resin is characterized in that the structure is shown as formula I:
wherein each M is independently selected fromPreferably, it isThe structures of M can be the same or different, and preferably, the same structure is adopted for M;
has the structure of
Wherein the values of n are respectively 60-100, preferably 64-88, and the values of n can be the same or different.
2. A process for the preparation of modified MQ resins according to claim 1, characterized by comprising the steps of:
(1)N2in the atmosphere, uniformly mixing alkoxy silane, an end-capping agent, tetramethyl disiloxane, ethanol, xylene and a catalyst 1, then adding water for reaction, and carrying out post-treatment to obtain powdery hydrogen-containing MQ resin;
(2)N2in the atmosphere, mixing the terminal vinyl silicone oil, the vinyl ring body, the chain extender and the catalyst 2 for reaction to obtain branched vinyl silicone oil;
(3)N2and (3) mixing the branched vinyl silicone oil prepared in the step (2) with a platinum catalyst in the atmosphere, and then adding the hydrogen-containing MQ resin prepared in the step (1) and a premixed solution of xylene to react to obtain the modified MQ resin.
3. The preparation method according to claim 2, wherein the raw materials in the steps (1) to (3) are added in the following amounts in parts by mass:
in the step (1), the raw materials comprise, by mass, 152-264 parts of alkoxysilane, 47-126 parts of an end-capping agent, 4-6 parts of tetramethyldisiloxane, 17-30 parts of ethanol and 39-67 parts of xylene; 10.4-0.8 parts of catalyst and 40-60 parts of water;
preferably 166-249 parts of alkoxy silane, 59-106 parts of end-capping agent, 4.5-5 parts of tetramethyl disiloxane, 19-27 parts of ethanol and 43-61 parts of xylene; 10.47-0.68 parts of catalyst and 53-58 parts of water;
in the step (2), raw materials comprise, by mass, 800-1600 parts of vinyl-terminated silicone oil, 4-10 parts of vinyl ring bodies, 400-600 parts of chain extender and 22-3 parts of catalyst;
preferably 1200-1575 parts of vinyl-terminated silicone oil, 5-9 parts of vinyl ring bodies, 525-575 parts of chain extender and 22.3-2.8 parts of catalyst;
in the step (3), the raw materials comprise, by mass, 1200-2210 parts of branched vinyl silicone oil, 0.5-1.2 parts of platinum catalyst, 99-191 parts of hydrogen-containing MQ resin and 100-200 parts of xylene;
preferably 1505-2159 parts of branched vinyl silicone oil, 0.8-1.2 parts of platinum catalyst, 123-170 parts of hydrogen-containing MQ resin and 120-170 parts of xylene.
4. The preparation method according to claim 2 or 3, wherein the hydrogen-containing MQ resin is prepared, wherein the hydrogen content is 0.03-0.06 wt%, preferably 0.04-0.05 wt%, and the molar ratio of M/Q is 0.7-0.9, preferably 0.75-0.85.
5. The method according to any one of claims 2 to 4, wherein in the step (1), the alkoxysilane is one or more of tetraethoxysilane, tetramethoxysilane, tetrapropoxysilane, preferably tetraethoxysilane;
the end-capping agent is one or more of hexamethyldisiloxane, trimethylchlorosilane, diphenyl tetramethyldisiloxane and phenyl dimethylchlorosilane, and preferably hexamethyldisiloxane;
the catalyst 1 is one or more of concentrated sulfuric acid, concentrated hydrochloric acid and trifluoromethanesulfonic acid, and preferably concentrated sulfuric acid;
in the step (1), the water is fed in batches or continuously, a dripping mode is preferred, the dripping time is 25-35 min, and the dripping and feeding time of the water is contained in the reaction time in the step (1);
in the step (1), the reaction conditions are as follows: the reaction temperature is 65-85 ℃, and preferably 68-75 ℃; the reaction time is 0.8-3 h and 1.5-2.5 h.
In the step (1), the post-treatment method specifically comprises the steps of distilling to remove ethanol and water, cooling the system to room temperature, extracting with xylene, washing with water until the pH value is 6.0-7.0, adding anhydrous calcium chloride, drying to be clear and transparent, filtering, and performing rotary evaporation to obtain powdery hydrogen-containing MQ resin;
preferably, the ethanol and the water are removed by distillation, a temperature rising distillation method is adopted, and the temperature in the distillation process is 120-140 ℃, preferably 125-135 ℃; the time is 3-6 h, preferably 4-5 h.
6. The preparation method according to any one of claims 2 to 5, wherein in the step (2), the terminal vinyl silicone oil is a terminal vinyl silicone oil with a viscosity of 1000 to 2000cp, preferably 1500 cp;
the vinyl ring body is one or more of tetravinyl tetramethylcyclotetrasiloxane, trivinyl trimethylcyclotrisiloxane and pentavinyl pentamethylcyclopentasiloxane, and preferably tetravinyl tetramethylcyclotetrasiloxane;
the chain extender is one or more of octamethylcyclotetrasiloxane, hexamethylcyclotrisiloxane, decamethylcyclopentasiloxane and DMC, and octamethylcyclotetrasiloxane is preferred;
the catalyst 2 is one or more of trifluoromethanesulfonic acid, trifluoroacetic acid, sulfonic acid resin and sulfuric acid, and is preferably trifluoromethanesulfonic acid;
in the step (2), the reaction conditions are as follows: the reaction temperature is 100-130 ℃, and preferably 115-125 ℃; the reaction time is 4-6 h, preferably 4.5-5.5 h;
and (2) a post-treatment method is included, and specifically, after the reaction system is cooled to room temperature, the reaction system is washed with water until the pH value is 6.0-7.0, then anhydrous calcium chloride is added, the reaction system is dried to be clear and transparent, and then the branched vinyl silicone oil is obtained by filtering.
7. The production method according to any one of claims 2 to 6, wherein in the step (3), the platinum catalyst is a Karster catalyst;
in the step (3), the reaction conditions are as follows: the reaction temperature is 50-70 ℃, and preferably 55-65 ℃; the reaction time is 1-3 h, preferably 1.5-2.5 h;
and (3) a post-treatment method is included, and specifically, the reaction system is cooled to room temperature, and then is subjected to adsorption filtration and rotary evaporation to obtain the modified MQ resin.
8. Use of a modified MQ resin according to claim 1 or prepared by a process according to any of claims 2 to 7 in the field of potting adhesives.
9. The addition type organic silicon pouring sealant is characterized by comprising the following raw materials in parts by mass: 150-250 parts of modified MQ resin, preferably 200-250 parts;
5-20 parts of hydrogen-containing silicone oil, preferably 8-15 parts;
0.3-2 parts of tackifier, preferably 0.5-1.5 parts;
0.5-4 parts of surfactant, preferably 1-3 parts;
0.01-0.2 part of catalyst, preferably 0.05-0.15 part;
the modified MQ resin is the modified MQ resin of claim 1 or prepared by the process of any of claims 2 to 7;
preferably, the hydrogen-containing silicone oil is selected from hydrogen-containing silicone oil with the hydrogen content of 0.1-1.6 wt%, and preferably hydrogen-containing silicone oil with the hydrogen content of 0.5-1.2 wt%; the tackifier is selected from one or two of gamma- (2, 3-epoxypropoxy) propyl trimethoxy silane or beta- (3, 4-epoxycyclohexyl) ethyl trimethoxy silane; the surfactant is selected from one or more of fluorinated acrylate copolymer, sodium alkyl benzene sulfonate and sodium sulfate, preferably fluorinated acrylic acid polymer; the catalyst is selected from one or more of chloroplatinic acid and a platinum catalyst, preferably a platinum catalyst.
10. The addition type organosilicon pouring sealant according to claim 9, wherein the raw materials contain optional auxiliary components, and the auxiliary components are 300-400 parts by mass, preferably 330-380 parts by mass; preferably, the auxiliary agent comprises an inhibitor, a thickening agent and a filler, wherein 5-15 parts of the inhibitor, 1-2 parts of the thickening agent and 300-400 parts of the filler;
preferably, the inhibitor is 1, 1-diphenyl-2-propyn-1-ol, the thickener is fumed silica, and the filler is alumina;
preferably, the addition type organic silicon pouring sealant is prepared by the following method:
under the stirring condition, sequentially adding a tackifier, hydrogen-containing silicone oil, an optional inhibitor, a filler, a catalyst, a surfactant and an optional thickener into the modified MQ resin, then stirring and dispersing at a high speed of 3000-4000 r/min for 55-65 min, and finally carrying out vacuum defoaming treatment under the pressure of 0.095-0.1 MPa to obtain the addition type organic silicon pouring sealant.
Technical Field
The invention relates to a modified MQ resin, a preparation method and application thereof, belonging to the technical field of pouring sealant.
Background
The potting materials are of a wide variety and are currently mainly used in the most applications for various synthetic polymers. Among them, epoxy resin, polyurethane elastomer and silicone polymer are most widely used.
The pouring sealant can also be applied to LED materials, chip packaging materials, solar cell materials, protective coatings and pouring materials of other electronic or electrical industries, and can also be widely applied to the fields of automobile electronic industry, household electronic products and the like. Epoxy resin is mainly used in the past, epoxy resin encapsulating materials are characterized by small shrinkage, no by-product and excellent electrical insulation performance, but are limited by molecular structures and low in heat resistance, are generally only used for encapsulating under normal temperature conditions, have no special requirements on mechanical and mechanical properties in use environments, and due to the fact that durability and physical property requirements are improved in recent years, silicone materials have chemically stable structures and are excellent in heat resistance, seasonal resistance and electrical insulation performance. Therefore, when severe weather and environmental green energy are required, it is regarded as important and used in a wide range of fields.
The pouring sealant is used for the purpose of sealing and caulking, but the pouring sealant is often caulked, because of the curing reaction, the surface energy of the pouring sealant is low, the adhesion with the substrate is poor, and the resin is often shrunk after curing. The adhesion between the pouring sealant and the substrate is generally improved by adding a primer and an adhesive, for example, patent nos. CN105586001A and CN 103773235A. However, as time goes on, the uncured 'oily substance' in the material seeps out, which can lead to poor sealing and seam plugging effects, or the strength is not enough, which can cause the material to fall off when slightly touching the sealing part; or dust accumulation and infiltration into the potting compound are generated with long-term exposure to the environment, resulting in reduced sealing and gap-plugging effects.
In order to solve the technical problems, the invention aims to further improve the sealing effect with a substrate and reduce the shortening of the service life of the pouring sealant caused by slow oil leakage along with the prolonging of time under the condition that a primer is already added into the pouring sealant.
Disclosure of Invention
The invention provides a modified MQ resin and a preparation method thereof, aiming at the technical problems of oil seepage and the like of the existing addition type silicone rubber pouring sealant after curing. The modified MQ resin prepared by the method belongs to solvent-free liquid MQ resin, is environment-friendly and low in VOC, can simplify the process, and has the following advantages under the condition that the reinforcing effect is basically unchanged: the time for preparing and dissolving the glue is shortened, the time for dissolving process is reduced, and the efficiency is improved; the viscosity is reduced, the fluidity is increased, the encapsulation and leveling are more sufficient, and the process operation is facilitated; the steric hindrance is reduced, the crosslinking and curing are easy, and the process time is further shortened.
Meanwhile, the invention also provides the application of the modified MQ resin in the field of pouring sealant, which not only can effectively solve the oil leakage problem of the pouring sealant, but also prolongs the bonding life of the pouring sealant and a base material.
In order to achieve the above object, in one aspect, the present invention provides a modified MQ resin, which has a structure represented by formula i:
wherein each M is independently selected fromPreferably, it isThe structures of M can be the same or different, and preferably, the same structure is adopted for M;
has the structure of
Wherein the values of n are respectively 60-100, preferably 64-88, and the values of n can be the same or different.
On the one hand, the invention also provides a preparation method of the modified MQ resin, which comprises the following steps:
(1) preparation of hydrogen-containing MQ resin:
N2in the atmosphere, uniformly mixing alkoxy silane, an end-capping agent, tetramethyl disiloxane, ethanol, xylene and a catalyst 1, then adding water for reaction, and carrying out post-treatment to obtain powdery hydrogen-containing MQ resin;
(2) preparing branched vinyl silicone oil:
N2in the atmosphere, mixing the terminal vinyl silicone oil, the vinyl ring body, the chain extender and the catalyst 2 for reaction to obtain branched vinyl silicone oil;
(3) preparation of modified MQ resin:
N2and (3) mixing the branched vinyl silicone oil prepared in the step (2) with a platinum catalyst in the atmosphere, and then adding the hydrogen-containing MQ resin prepared in the step (1) and a premixed solution of xylene to react to obtain the modified MQ resin.
In the preparation method, the addition amounts of the raw materials in the steps (1) to (3) are respectively as follows by mass parts:
in the step (1), the raw materials comprise, by mass, 152-264 parts of alkoxysilane, 47-126 parts of an end-capping agent, 4-6 parts of tetramethyldisiloxane, 17-30 parts of ethanol and 39-67 parts of xylene; 10.4-0.8 parts of catalyst and 40-60 parts of water;
preferably 166-249 parts of alkoxy silane, 59-106 parts of end-capping agent, 4.5-5 parts of tetramethyl disiloxane, 19-27 parts of ethanol and 43-61 parts of xylene; 10.47-0.68 parts of catalyst and 53-58 parts of water;
in the step (2), raw materials comprise, by mass, 800-1600 parts of vinyl-terminated silicone oil, 4-10 parts of vinyl ring bodies, 400-600 parts of chain extender and 22-3 parts of catalyst;
preferably 1200-1575 parts of vinyl-terminated silicone oil, 5-9 parts of vinyl ring bodies, 525-575 parts of chain extender and 22.3-2.8 parts of catalyst;
in the step (3), the raw materials comprise, by mass, 1200-2210 parts of branched vinyl silicone oil, 0.5-1.2 parts of platinum catalyst, 99-191 parts of hydrogen-containing MQ resin and 100-200 parts of xylene;
preferably 1505-2159 parts of branched vinyl silicone oil, 0.8-1.2 parts of platinum catalyst, 123-170 parts of hydrogen-containing MQ resin and 120-170 parts of xylene.
In the preparation method of the invention, in the step (1), the alkoxy silane is one or more of tetraethoxy silane, tetramethoxy silane and tetrapropoxy silane, and is preferably tetraethoxy silane;
the end-capping agent is one or more of hexamethyldisiloxane, trimethylchlorosilane, diphenyl tetramethyldisiloxane and phenyl dimethylchlorosilane, and preferably hexamethyldisiloxane;
the catalyst 1 is one or more of 95-98 wt% concentrated sulfuric acid, 36-38 wt% concentrated hydrochloric acid and trifluoromethanesulfonic acid, and is preferably 95-98 wt% concentrated sulfuric acid;
in the preparation method, in the step (1), the water is preferably fed in batches or continuously, more preferably in a dropwise adding mode, the dropwise adding time is 25-35 min, and the dropwise adding and feeding time of the water is contained in the reaction time in the step (1);
the preparation method comprises the following reaction conditions in the step (1): the reaction temperature is 65-85 ℃, and preferably 68-75 ℃; the reaction time is 0.8-3 h and 1.5-2.5 h.
In the preparation method, in the step (1), the post-treatment comprises extraction, water washing, drying, rotary evaporation and other conventional operation processes in the field, in some examples, the post-treatment method adopted is specifically that ethanol and water are removed by distillation, after the system is cooled to room temperature, xylene is firstly adopted for extraction, water washing is carried out until the pH value is 6.0-7.0, then anhydrous calcium chloride is added for drying until the solution is clear and transparent, then the solution is filtered to remove salt (namely the calcium chloride after water absorption), and finally, the powdery hydrogen-containing MQ resin is obtained by rotary evaporation;
preferably, the ethanol and the water are removed by distillation, a temperature-rising distillation method is adopted, the distillation is carried out at normal pressure, and the temperature in the distillation process is 120-140 ℃, preferably 125-135 ℃; the time is 3-6 h, preferably 4-5 h;
preferably, the rotary evaporation is carried out at the temperature of 130-150 ℃.
The room temperature in the invention refers to the ambient temperature in the preparation process, and is generally 15-25 ℃.
According to the preparation method, in the step (1), the hydrogen content of the prepared hydrogen-containing MQ resin is 0.03-0.06 wt%, preferably 0.04-0.05 wt%, and the molar ratio of M/Q is 0.7-0.9, preferably 0.75-0.85, wherein in some examples, the molar content of M is 0.56-1.13 (calculated by the amount of the M raw material in the process of preparing the hydrogen-containing MQ resin polymer macromolecules), preferably 0.75-0.85.
In the preparation method, in the step (2), the vinyl-terminated silicone oil is vinyl-terminated silicone oil with the viscosity of 1000-2000 cp, preferably 1300-1800 cp;
the vinyl ring body is one or more of tetravinyl tetramethylcyclotetrasiloxane, trivinyl trimethylcyclotrisiloxane and pentavinyl pentamethylcyclopentasiloxane, and preferably tetravinyl tetramethylcyclotetrasiloxane;
the chain extender is one or more of octamethylcyclotetrasiloxane, hexamethylcyclotrisiloxane, decamethylcyclopentasiloxane and DMC (mixture of octamethylcyclotetrasiloxane, hexamethylcyclotrisiloxane and decamethylcyclopentasiloxane), and is preferably dimethylcyclotetrasiloxane;
the catalyst 2 is one or more of trifluoromethanesulfonic acid, trifluoroacetic acid, sulfonic acid resin and sulfuric acid, and is preferably trifluoromethanesulfonic acid.
The preparation method comprises the following reaction conditions in the step (2): the reaction temperature is 100-130 ℃, and preferably 115-125 ℃; the reaction time is 4-6 h, preferably 4.5-5.5 h;
the preparation method comprises the following steps of (2) washing, drying and other post-treatment processes, wherein in some examples, the post-treatment process comprises the steps of cooling the reaction system to room temperature, washing with water until the pH value is 6.0-7.0, adding anhydrous calcium chloride, drying until the reaction system is clear and transparent, and filtering to remove salt to obtain the branched vinyl silicone oil.
In the preparation method, in the step (3), the platinum catalyst is a Karster catalyst.
The preparation method of the invention, in the step (3), the reaction conditions are as follows: the reaction temperature is 50-70 ℃, and preferably 55-65 ℃; the reaction time is 1-3 h, preferably 1.5-2.5 h.
In the preparation method, the step (3) further comprises post-treatment processes such as filtering, drying and the like, and in some examples, the post-treatment method is specifically that the reaction system is cooled to room temperature, and then the reaction system is subjected to adsorption filtering and rotary evaporation to obtain modified MQ resin;
preferably, the adsorption filtration is carried out, and the adsorbent is diatomite; the rotary evaporation temperature is 130-150 ℃.
On the other hand, the invention provides the application of the modified MQ resin in the field of pouring sealant. The modified MQ resin is particularly suitable for preparing addition type organic silicon pouring sealant.
An addition type organic silicon pouring sealant comprises the following raw materials in parts by mass:
150-250 parts of modified MQ resin, preferably 200-250 parts;
5-20 parts of hydrogen-containing silicone oil, preferably 8-15 parts;
0.3-2 parts of tackifier, preferably 0.5-1.5 parts;
0.5-4 parts of surfactant, preferably 1-3 parts;
0.01 to 0.2 part of catalyst, preferably 0.05 to 0.15 part.
In the addition type organic silicon pouring sealant, the hydrogen-containing silicone oil is selected from the hydrogen-containing silicone oil with the hydrogen content of 0.1-1.6 wt%, and preferably the hydrogen-containing silicone oil with the hydrogen content of 0.5-1.2 wt%;
the tackifier is selected from one or two of gamma- (2, 3-epoxypropoxy) propyl trimethoxy silane (KH-570) or beta- (3, 4-epoxycyclohexyl) ethyl trimethoxy silane (A-186);
the surfactant is selected from one or more of fluorinated acrylate copolymer, sodium alkyl benzene sulfonate and sodium sulfate, preferably fluorinated acrylic acid polymer;
the catalyst is selected from one or more of chloroplatinic acid and a platinum catalyst, preferably a platinum catalyst.
In the addition type organosilicon pouring sealant, the raw materials also contain optional auxiliary components such as an inhibitor, a thickening agent, a filler and the like, and the auxiliary components account for 300-400 parts by mass, preferably 330-380 parts by mass; 5-15 parts of inhibitor, 1-2 parts of thickener and 300-400 parts of filler;
preferably, the inhibitor is 1, 1-diphenyl-2-propyn-1-ol, the thickener is fumed silica, and the filler is alumina.
The preparation method of the addition type organic silicon pouring sealant comprises the following steps:
under the stirring condition, sequentially adding an auxiliary agent (such as 1, 1-diphenyl-2-propyne-1-ol, aluminum oxide), a catalyst, a surfactant, an optional thickener and the like (such as fumed silica) into the modified MQ resin, then stirring at a high speed of 3000-4000 r/min for 55-65 min, and finally carrying out vacuum defoaming treatment under the pressure of 0.095-0.1 MPa to obtain the addition type organic silicon pouring sealant.
The technical scheme of the invention has the beneficial effects that:
the modified MQ resin structure prepared by the method is liquid under similar M/Q ratio due to the access of the D chain link, belongs to solvent-free liquid MQ resin, is environment-friendly and low in VOC, reduces the mixing difficulty with other systems, and simplifies the process; secondly, the modified MQ resin structure not only contains a Q-type chain and a D-type chain, but also has the characteristics of resin and silicone oil, and the Q-type chain and the D-type chain are relatively independent, so that the reinforcing property of a Q chain link and the flexibility of a D chain link are respectively maintained; the specific branched structure of the D chain can obtain a solvent-free product with lower viscosity under the condition of the same molecular weight.
The pouring sealant prepared by the modified MQ resin not only solves the technical problems of oil leakage and the like of the existing addition type silicone rubber pouring sealant after curing, but also shortens the dissolution time of the prepared sealant, reduces the dissolution process time and improves the efficiency; the viscosity is reduced, the fluidity is increased, the encapsulation and leveling are more sufficient, and the process operation is facilitated; the steric hindrance is reduced, the crosslinking and curing are easy, the process time is further shortened, and the like.
Wherein the D-type chain structure and the Q-type chain structure are well known in the art, and are specifically as follows:type Q:
drawings
Fig. 1 is an infrared spectrum of a modified MQ resin prepared in example 1;
fig. 2 is an infrared spectrum of a modified MQ resin prepared in example 2;
FIG. 3 is an infrared spectrum of a modified MQ resin prepared in example 3;
fig. 4 is an infrared spectrum of a modified MQ resin prepared in example 4;
FIG. 5 is an infra-red spectrum of a modified MQ resin prepared in example 5;
fig. 6 is an infrared spectrum of a modified MQ resin prepared in example 6;
fig. 7 is an infrared spectrum of a modified MQ resin prepared in example 7;
fig. 8 is an infrared spectrum of a modified MQ resin prepared in comparative example 1;
fig. 9 is an infrared spectrum of the MDQ resin prepared in comparative example 2.
Detailed Description
The technical solution of the present invention is further illustrated by the following specific examples, which are only used for illustrating the method of the present invention and do not limit the scope of the present invention.
< analytical test method >
1. The product hydrogen content was tested by titration: accurately weighing 0.1000-0.3000 g (hydrogen content is lower than 0.2%, maximum sampling amount is 0.3g) of sample in a 250ml iodine measuring flask, and adding 20ml of carbon tetrachloride for dissolving; then adding 10ml of 0.2mol/L bromine-acetic acid solution and 0.5ml of water, covering a plug, shaking up, sealing the bottle mouth with carbon tetrachloride liquid, and placing in a dark place for reaction for 30 min; after the reaction is completed, adding 25ml of potassium iodide solution with the mass fraction of 10%, forcibly shaking for 2-3 min, and washing the bottle mouth with deionized water; titrating with 0.1mol/L sodium thiosulfate standard solution, adding 3 drops of starch solution when the solution changes from dark red to bright red, and continuing to titrate, wherein the end point is determined when the solution just changes from blue to colorless. And simultaneously carrying out a blank experiment, carrying out parallel titration for 2 times in the blank experiment, taking an average value, and if the difference value of the two titration results is large, carrying out titration again.
Calculation formula of hydrogen content:
WH-the mass fraction of hydrogen,
C——Na2S2O3the molar concentration of (a) is mol/L,
V0blank experiment consuming Na2S2O3The volume of the solution is ml, and the volume of the solution,
V1titration of the sample to consume Na2S2O3The volume of the solution is ml, and the volume of the solution,
m-mass of sample g.
2. Adopt infrared test product structure: thermo Scientific IS 5; the positions of the groups in the infrared test spectrogram are as follows: Si-CH ═ CH2：1500-1600cm-1；Si-CH3：1200-1300cm-1；C-H:2900-3000cm-1；Si-O-Si:1100-1300cm-1；Si-Ph:1000-1100cm-1；Si-H：2050-2300cm-1。
3. And (3) testing oil permeability: a certain mass (m)0) The pouring sealant is coated on a tinplate, vulcanized for 24 hours at room temperature and placed in an environment with the temperature of 10 ℃. Wiping off the oil exuded from the surface of the product every 2 days, testing the residual mass, and calculating the total mass (m) of the oil lost at each time point1). The oil permeability is expressed by the following formula: oil permeability is m1/m0*100％；
4. Testing the bonding strength: GB/T7124-.
< Source information of raw Material >
Tetraethoxysilane, caruncle cheng chemicals ltd, AR;
tetramethoxysilane, caruncle cheng chemicals ltd, AR;
tetrapropoxysilane, caruncle cheng optical chemical ltd, AR;
hexamethyldisiloxane, alatin reagent ltd, AR;
trimethylchlorosilane, alatin reagent, ltd, AR;
diphenyltetramethyldisiloxane, Aladdin reagent, Inc., AR;
phenyldimethylchlorosilane, alatin reagent, ltd, AR;
tetramethyldisiloxane, Aladdin reagent, Inc., AR;
ethanol, julong chemical co ltd, AR;
xylene, julong chemical limited, AR;
concentrated hydrochloric acid, cromion chemical reagents ltd, AR;
octamethylcyclotetrasiloxane, caruncle cheng photochemical ltd, AR;
decamethylcyclopentasiloxane, caruncle cheng chemicals ltd, AR;
hexamethylcyclotrisiloxane, caruncle cheng photochemical ltd, AR;
DMC, caruncle cheng chemicals ltd, AR;
vinyl-terminated silicone oil, model number DY-V401E, Dayi Limited, Shandong;
divinyltetramethyldisiloxane, caruncle cheng optical chemicals, inc, AR;
tetravinyl tetramethylcyclotetrasiloxane, caruncle chenopodium chemical ltd, AR;
trivinyltrimethylcyclotrisiloxane, caruncle cheng photochemical ltd, AR;
pentavinyl pentamethylcyclopentasiloxane, caruncle chenopodium chemical ltd, AR;
trifluoromethanesulfonic acid, alatin reagent, ltd, AR;
trifluoroacetic acid, alatin reagent, ltd, AR;
sulfonic acid resins, alatin reagent ltd, AR;
sulfuric acid, cromion chemical agents ltd, AR;
platinum catalyst, Anbia Limited, Karster platinum catalyst Pt-5000
Hydrogen-containing silicone oil, model 202 of a new material Kaiser Material Co., Ltd., of Zhejiang, with a hydrogen content of 1.55 wt%;
1, 1-diphenyl-2-propyn-1-ol, alatin reagent ltd, AR;
vinyl MQ resin, Jiangxi Xinjiayi Limited, model XJY-8206A, AR;
fumed silica, winning moraxel limited, model R972;
surfactant FS-60, DuPont, AR;
alumina filler, Guangdong ultra-new material science and technology limited, particle size 10-30 um;
silane coupling agent A-186, Guangzhou Viruna chemical Co., Ltd., AR;
diatomaceous earth, cromion chemical reagents ltd, CP.
Other raw materials and reagents may be purchased from commercial sources unless otherwise specified.
[ example 1 ]
(1) Preparation of hydrogen-containing MQ resin:
equipped with a stirrer, a thermometer, a condenser and N2Adding 208g of tetraethoxysilane, 59g of hexamethyldisiloxane, 5g of tetramethyldisiloxane, 22g of ethanol, 49g of xylene and 0.5g of 98 wt% concentrated sulfuric acid into a three-neck flask in the atmosphere, stirring for 30min, then dropwise adding 50g of water, completing dropwise adding for 30min, then heating to 85 ℃ for reaction for 1h, heating to distill off ethanol and water, steaming to a liquid phase temperature of 130 ℃, preserving heat for 4.5h, and then cooling to room temperature; extracting with dimethylbenzene, washing with water until the pH value is 6.0-7.0, adding anhydrous calcium chloride, drying until the mixture is clear and transparent, filtering to remove salt, and then carrying out rotary evaporation at 130 ℃ to obtain hydrogen-containing MQ resin solid powder.
The hydrogen content of the product was determined by the hydrogen content determination method, the hydrogen content was measured to be 0.06 wt%, and the molar ratio M/Q was calculated by the amount of the added materials to be 0.8, wherein the molar content of M was 0.8.
(2) Preparing branched vinyl silicone oil:
equipped with a stirrer, a thermometer, a condenser and N21000g of vinyl-terminated silicone oil (the viscosity is 1500cp), 5g of tetravinyl tetramethylcyclotetrasiloxane, 500g of octamethylcyclotetrasiloxane and 2.5g of trifluoromethanesulfonic acid are added into a three-neck flask in the atmosphere, stirring is started, the stirring speed is controlled at 400r/min, the temperature is raised to 130 ℃, then the reaction is carried out for 4h, then a heating system is closed, and the temperature is reduced to the room temperature. Washing with water until the pH value is 6.0-7.0, adding anhydrous calcium chloride, drying until the mixture is clear and transparent, and filtering to remove salt to obtain the branched vinyl silicone oil.
(3) Preparation of modified MQ resin:
equipped with a stirrer, a thermometer, a condenser and N21505g of branched vinyl silicone oil prepared in the step (2) and 0.8g of platinum catalyst were added to a three-necked flask in an atmosphere, and stirred for 1 hour, 124.26g of hydrogen-containing MQ resin powder prepared in the step (1) and 125g of xylene were premixed and added dropwise to the system, and the mixture was heated to 70 ℃ to react for 1 hour. Then turn off heatingStirring the system, cooling to room temperature, performing adsorption filtration (adsorbent diatomite) and rotary evaporation at 130 deg.C to obtain modified MQ resin (shown in figure 1 by infrared test), wherein M is of structureThe average n value is 100. The positions of the various groups in FIG. 1 are as follows: Si-CH ═ CH2：1500-1600cm-1；Si-CH3：1200-1300cm-1；C-H:2900-3000cm-1；Si-O-Si:1100-1300cm-1. The modified MQ resin product of the example is proved to contain Si-CH ═ CH in the structure2，Si-CH3Si-O-Si groups, free of Si-H groups.
The hydrogen content of the product is measured by a hydrogen content measuring method to be 75ppm (the Si-H group content is proved to be extremely low, and the hydrogen content can be considered to be complete reaction after being less than 100 ppm), which indicates that the hydrogen-containing MQ resin and the side vinyl silicone oil are completely reacted.
[ example 2 ]
(1) Preparation of hydrogen-containing MQ resin:
adding 152g of tetramethoxysilane, 80g of trimethylchlorosilane, 4.7g of tetramethyldisiloxane, 19g of ethanol, 43g of xylene and 0.5g of 38 wt% concentrated hydrochloric acid into a three-neck flask with an atmosphere of N2, stirring for 30min, then dropwise adding 53g of water, after dropwise adding for 25min, heating to 80 ℃, reacting for 1.5h, heating, distilling to remove ethanol and water, evaporating to a liquid phase temperature of 120 ℃, preserving heat for 4h, and then cooling to room temperature; extracting with dimethylbenzene, washing with water until the pH value is 6.0-7.0, adding anhydrous calcium chloride, drying until the mixture is clear and transparent, filtering to remove salt, and performing rotary evaporation to obtain hydrogen-containing MQ resin solid powder.
Determination of the hydrogen content of the product by means of the determination of the hydrogen content determination method, the hydrogen content is 0.048 wt%, the molar ratio M/Q is 0.8 by means of the amount of the added materials, and the molar content of M is 0.8.
(2) Preparing branched vinyl silicone oil:
1250g of vinyl-terminated silicone oil (with the viscosity of 1500cp), 6g of trivinyltrimethylcyclotetrasiloxane, 525g of hexamethylcyclotrisiloxane and 2g of trifluoroacetic acid are added into a three-neck flask provided with a stirrer, a thermometer, a condenser and an N2 atmosphere, stirring is started, the stirring speed is controlled at 400r/min, the temperature is increased to 125 ℃, then the reaction is carried out for 4.5h, and then a heating system is closed, and the temperature is reduced to the room temperature. Washing with water until the pH value is 6.0-7.0, adding anhydrous calcium chloride, drying until the mixture is clear and transparent, and filtering to remove salt to obtain the branched vinyl silicone oil.
(3) Preparation of modified MQ resin:
into a three-necked flask equipped with a stirrer, a thermometer, a condenser and an atmosphere of N2, 1781g of branched vinyl silicone oil and 0.5g of platinum catalyst were charged and stirred for 1 hour, 144g of hydrogen-containing MQ resin powder and 145g of xylene were premixed and slowly dropped into the system, and heated to 65 ℃ to react for 1.5 hours. Then closing the heating and stirring system, cooling to room temperature, and then performing adsorption filtration and rotary evaporation on the mixture to obtain the modified MQ resin (the infrared test pattern is shown in figure 2), wherein the M structure isThe average n value was 88. The positions of the groups in FIG. 2 are as follows:
Si-CH＝CH2：1500-1600cm-1；Si-CH3：1200-1300cm-1；C-H:2900-3000cm-1；Si-O-Si:1100-1300cm-1. The modified MQ resin product of the example is proved to contain Si-CH ═ CH in the structure2，Si-CH3Si-O-Si groups, free of Si-H groups.
The hydrogen content of the product is measured by a hydrogen content measuring method to be 74ppm <100ppm, which indicates that the hydrogen-containing MQ resin and the side vinyl silicone oil completely react.
[ example 3 ]
(1) Preparation of hydrogen-containing MQ resin:
adding 264g of tetrapropoxysilane, 106g of diphenyl tetramethyldisiloxane, 4.5g of tetramethyldisiloxane, 30g of ethanol, 67g of xylene and 0.75g of trifluoromethanesulfonic acid into a three-neck flask with an atmosphere of N2, stirring for 30min, dropwise adding 55g of water for 35min, heating to 75 ℃ for reacting for 2h, heating to distill off ethanol and water, steaming to 140 ℃ of liquid phase temperature, keeping the temperature for 5h, and cooling to room temperature; extracting with dimethylbenzene, washing with water until the pH value is 6.0-7.0, adding anhydrous calcium chloride, drying until the mixture is clear and transparent, filtering to remove salt, and performing rotary evaporation to obtain hydrogen-containing MQ resin solid powder.
Determination of the hydrogen content of the product by means of the determination of the hydrogen content determination method the hydrogen content is 0.039 wt.%, the molar ratio M/Q is 0.8, calculated by means of the amount of material added, where the molar content of M is 0.8.
(2) Preparing branched vinyl silicone oil:
1500g of vinyl silicone oil (with the viscosity of 1500cp), 7.5g of pentavinyl pentamethyl cyclotetrasiloxane, 550g of decamethyl cyclopentasiloxane and 3g of sulfonic acid resin are added into a three-neck flask with an atmosphere of a stirrer, a thermometer, a condenser and N2, stirring is started, the stirring speed is controlled to be 400r/min, the temperature is increased to 120 ℃, then the reaction is carried out for 3h, and then a heating system is closed and the temperature is reduced to the room temperature. Washing with water until the pH value is 6.0-7.0, adding anhydrous calcium chloride, drying until the mixture is clear and transparent, and filtering to remove salt to obtain the branched vinyl silicone oil.
(3) Preparation of modified MQ resin:
equipped with a stirrer, a thermometer, a condenser and N2Adding 2058g of branched vinyl silicone oil and 1g of platinum catalyst into a three-neck flask in the atmosphere, stirring for 1h, premixing 170g of hydrogen-containing MQ resin powder and 170g of dimethylbenzene, slowly dripping into the system, and heating to 60 ℃ for reaction for 2 h. Then closing the heating and stirring system, cooling to room temperature, and then performing adsorption filtration and rotary evaporation on the mixture to obtain the modified MQ resin (the infrared test pattern is shown in figure 3), wherein the M structure isThe average n value was 73. The positions of the groups in fig. 3 are as follows: Si-CH ═ CH2：1500-1600cm-1；Si-CH3：1200-1300cm-1；C-H:2900-3000cm-1；Si-O-Si:1100-1300cm-1(ii) a The modified MQ resin product of the example is proved to contain Si-CH ═ CH in the structure2，Si-CH3Si-O-Si groups, free of Si-H groups.
The hydrogen content of the product is measured by a hydrogen content measuring method to be 77ppm <100ppm, which indicates that the hydrogen-containing MQ resin and the side vinyl silicone oil completely react.
[ example 4 ]
(1) Preparation of hydrogen-containing MQ resin:
adding 208g of tetraethoxysilane, 126g of phenyldimethylchlorosilane, 4.3g of tetramethyldisiloxane, 27g of ethanol, 61g of xylene and 0.7g of 98 wt% concentrated sulfuric acid into a three-neck flask with an atmosphere of N2, stirring for 30min, then dropwise adding 58g of water, after finishing dropwise adding for 27min, heating to 70 ℃, reacting for 2.5h, heating, distilling to remove ethanol and water, evaporating to a liquid phase temperature of 125 ℃, preserving heat for 3h, and then cooling to room temperature; extracting with dimethylbenzene, washing with water until the pH value is 6.0-7.0, adding anhydrous calcium chloride, drying until the mixture is clear and transparent, filtering to remove salt, and performing rotary evaporation to obtain hydrogen-containing MQ resin solid powder.
Determination of the hydrogen content of the product by means of the hydrogen content determination method the hydrogen content is measured to be 0.034 wt.%, the molar ratio M/Q is calculated by adding material amounts to be 0.75, the molar content of M being 0.75.
(2) Preparing branched vinyl silicone oil:
1575g of vinyl terminated silicone oil (with the viscosity of 1000cp), 9g of tetravinyl tetramethylcyclotetrasiloxane, 500g of DMC and 2.5g of concentrated sulfuric acid are added into a three-neck flask with an atmosphere of stirrer, thermometer, condenser and N2, stirring is started, the stirring speed is controlled at 400r/min, the temperature is increased to 115 ℃, then the reaction is carried out for 5.5h, and then the heating system is closed, and the temperature is reduced to the room temperature. Washing with water until the pH value is 6.0-7.0, adding anhydrous calcium chloride, drying until the mixture is clear and transparent, and filtering to remove salt to obtain the branched vinyl silicone oil.
(3) Preparation of modified MQ resin:
equipped with a stirrer, a thermometer, a condenser and N22159g of branched vinyl silicone oil and 1.5g of platinum catalyst are added into a three-neck flask in the atmosphere, stirred for 1h, 191g of hydrogen-containing MQ resin powder and 190g of xylene are premixed and slowly dripped into the system, and the mixture is heated to 55 ℃ to react for 2.5 h. Then closing the heating and stirring system, cooling to room temperature, and then performing adsorption filtration and rotary evaporation on the mixture to obtain the modified MQ resin (the infrared test pattern is shown in figure 4), wherein the M structure isThe average n value is 64. The positions of the groups in fig. 4 are as follows:
Si-CH＝CH2：1500-1600cm-1；Si-CH3：1200-1300cm-1；C-H:2900-3000cm-1；Si-O-Si:1100-1300cm-1；Si-Ph:1000-1100cm-1(ii) a The modified MQ resin product of the example is proved to contain Si-CH ═ CH in the structure2，Si-CH3Si-O-Si group, Si-Ph group, Si-H group being absent.
The hydrogen content of the product is measured by a hydrogen content measuring method to be 70ppm <100ppm, which indicates that the hydrogen-containing MQ resin and the side vinyl silicone oil completely react.
[ example 5 ]
(1) Preparation of hydrogen-containing MQ resin:
adding 208g of tetraethoxysilane, 59g of hexamethyldisiloxane, 4g of tetramethyldisiloxane, 22g of ethanol, 49g of xylene and 0.5g of 98 wt% concentrated sulfuric acid into a three-neck flask with an atmosphere of N2, stirring for 30min, then dropwise adding 60g of water, finishing dropwise adding 32min, then heating to 65 ℃ for reaction for 3h, heating to distill off ethanol and water, steaming to a liquid phase temperature of 135 ℃, preserving heat for 6h, and then cooling to room temperature; extracting with dimethylbenzene, washing with water until the pH value is 6.0-7.0, adding anhydrous calcium chloride, drying until the mixture is clear and transparent, filtering to remove salt, and performing rotary evaporation to obtain hydrogen-containing MQ resin solid powder.
Determination of the hydrogen content of the product by the determination of the hydrogen content determination method the hydrogen content is 0.048 wt%, the molar ratio M/Q is 0.85 by the amount of the added materials, wherein the molar content of M is 0.85.
(2) Preparing branched vinyl silicone oil:
1600g of vinyl-terminated silicone oil (the viscosity is 2000cp), 10g of tetravinyl tetramethylcyclotetrasiloxane, 600g of octamethylcyclotetrasiloxane and 3g of trifluoromethanesulfonic acid are added into a three-neck flask equipped with a stirrer, a thermometer, a condenser and an atmosphere of N2, stirring is started, the stirring speed is controlled at 400r/min, the temperature is increased to 110 ℃, then the reaction is carried out for 6 hours, and then a heating system is closed, and the temperature is reduced to the room temperature. Washing with water until the pH value is 6.0-7.0, adding anhydrous calcium chloride, drying until the mixture is clear and transparent, and filtering to remove salt to obtain the branched vinyl silicone oil.
(3) Preparation of modified MQ resin:
equipped with a stirrer, a thermometer, a condenser and N22210g of branched vinyl silicone oil and 1.2g of platinum catalyst are added into a three-neck flask with atmosphere, stirred for 1h, 123g of hydrogen-containing MQ resin powder and 120g of xylene are premixed and slowly dripped into the system, and the mixture is heated to 50 ℃ to react for 3 h. Then closing the heating and stirring system, cooling to room temperature, and then performing adsorption filtration and rotary evaporation on the mixture to obtain the modified MQ resin (the infrared test pattern is shown in figure 5), wherein the M structure isThe average n value was 60. The positions of the various groups in FIG. 5 are as follows: Si-CH ═ CH2：1500-1600cm-1；Si-CH3：1200-1300cm-1；C-H:2900-3000cm-1；Si-O-Si:1100-1300cm-1(ii) a The product of this example is proved to contain Si-CH ═ CH2，Si-CH3Si-O-Si, no Si-H groups.
The hydrogen content of the product is determined by a hydrogen content determination method to be 72ppm <100ppm, which indicates that the hydrogen-containing MQ resin and the side vinyl silicone oil completely react.
[ example 6 ]
(1) Preparation of hydrogen-containing MQ resin:
adding 250g of tetraethoxysilane, 71g of hexamethyldisiloxane, 6g of tetramethyldisiloxane, 26g of ethanol, 59g of xylene and 0.7g of 98 wt% concentrated sulfuric acid into a three-neck flask with a stirrer, a thermometer, a condenser and an N2 atmosphere, stirring for 30min, then dropwise adding 60g of water, finishing dropwise adding 30min, then heating to 85 ℃ for reaction for 1h, heating to distill off ethanol and water, steaming to a liquid phase temperature of 130 ℃, preserving heat for 4h, and then cooling to room temperature; extracting with dimethylbenzene, washing with water until the pH value is 6.0-7.0, adding anhydrous calcium chloride, drying until the mixture is clear and transparent, filtering to remove salt, and performing rotary evaporation to obtain hydrogen-containing MQ resin solid powder.
Determination of the hydrogen content of the product by means of the determination of the hydrogen content determination method the hydrogen content is determined to be 0.048 wt%, the molar ratio M/Q is calculated to be 0.9 by adding the material amount, wherein the molar content value M is 1.13.
(2) Preparing branched vinyl silicone oil:
1200g of vinyl-terminated silicone oil (with the viscosity of 1500cp), 6g of tetravinyl tetramethylcyclotetrasiloxane, 600g of octamethylcyclotetrasiloxane and 3g of trifluoromethanesulfonic acid are added into a three-neck flask equipped with a stirrer, a thermometer, a condenser and an atmosphere of N2, stirring is started, the stirring speed is controlled at 400r/min, the temperature is increased to 100 ℃, then the reaction is carried out for 5 hours, and then a heating system is closed, and the temperature is reduced to the room temperature. Washing with water until the pH value is 6.0-7.0, adding anhydrous calcium chloride, drying until the mixture is clear and transparent, and filtering to remove salt to obtain the branched vinyl silicone oil.
(3) Preparation of modified MQ resin:
equipped with a stirrer, a thermometer, a condenser and N21800g of branched vinyl silicone oil and 0.95g of platinum catalyst are added into a three-neck flask with atmosphere, stirred for 1h, 149g of hydrogen-containing MQ resin powder and 150g of xylene are premixed and slowly dripped into the system, and the mixture is heated to 60 ℃ to react for 2 h. Then closing the heating and stirring system, cooling to room temperature, and then performing adsorption filtration and rotary evaporation on the mixture to obtain the modified MQ resin (the infrared test pattern is shown in figure 6), wherein the M structure isThe average n value is 100. The positions of the groups in fig. 6 are as follows:
Si-CH＝CH2：1500-1600cm-1；Si-CH3：1200-1300cm-1；C-H:2900-3000cm-1；Si-O-Si:1100-1300cm-1(ii) a The modified MQ resin product of the example is proved to contain Si-CH ═ CH in the structure2，Si-CH3Si-O-Si groups, free of Si-H groups.
The hydrogen content of the product is determined by a hydrogen content determination method to be 75ppm <100ppm, which indicates that the hydrogen-containing MQ resin and the side vinyl silicone oil completely react.
[ example 7 ]
(1) Preparation of hydrogen-containing MQ resin:
adding 166g of tetraethoxysilane, 47g of hexamethyldisiloxane, 4g of tetramethyldisiloxane, 17g of ethanol, 39g of xylene and 0.4g of 98 wt% concentrated sulfuric acid into a three-neck flask with an atmosphere of N2, stirring for 30min, then dropwise adding 40g of water, finishing dropwise adding 30min, heating to 68 ℃, reacting for 1h, heating, distilling to remove ethanol and water, steaming to a liquid phase temperature of 140 ℃, preserving the temperature for 5h, and then cooling to room temperature; extracting with dimethylbenzene, washing with water until the pH value is 6.0-7.0, adding anhydrous calcium chloride, drying until the mixture is clear and transparent, filtering to remove salt, and performing rotary evaporation to obtain hydrogen-containing MQ resin solid powder.
Determination of the hydrogen content of the product by means of the determination of the hydrogen content determination method the hydrogen content is determined to be 0.048 wt%, the molar ratio M/Q is calculated to be 0.7 by adding the material amount, wherein the molar content value M is 0.56.
(2) Preparing branched vinyl silicone oil:
adding 800g of vinyl-terminated silicone oil (the viscosity is 1500cp), 4g of tetravinyl tetramethylcyclotetrasiloxane, 400g of octamethylcyclotetrasiloxane and 2g of trifluoromethanesulfonic acid into a three-neck flask with a stirrer, a thermometer, a condenser and an N2 atmosphere, starting stirring, controlling the stirring speed to be 400r/min, heating to 130 ℃, reacting for 3 hours, then closing a heating system, and cooling to room temperature. Washing with water until the pH value is 6.0-7.0, adding anhydrous calcium chloride, drying until the mixture is clear and transparent, and filtering to remove salt to obtain the branched vinyl silicone oil.
(3) Preparation of modified MQ resin:
equipped with a stirrer, a thermometer, a condenser and N21200g of branched vinyl silicone oil and 0.65g of platinum catalyst are added into a three-neck flask with atmosphere, stirred for 1h, 99.4g of hydrogen-containing MQ resin powder and 100g of dimethylbenzene are premixed and then slowly dripped into the system, and the mixture is heated to 60 ℃ to react for 2 h. Then closing the heating and stirring system, cooling to room temperature, and then performing adsorption filtration and rotary evaporation on the mixture to obtain the modified MQ resin (the infrared test pattern is shown in figure 7), wherein the M structure isThe average n value is 100. The positions of the groups in fig. 7 are as follows:
Si-CH＝CH2：1500-1600cm-1；Si-CH3：1200-1300cm-1；C-H:2900-3000cm-1；Si-O-Si:1100-1300cm-1(ii) a The modified MQ resin product of the example is proved to contain Si-CH ═ CH in the structure2，Si-CH3Si-O-Si groups, free of Si-H groups.
The hydrogen content of the product is determined by a hydrogen content determination method to be 75ppm <100ppm, which indicates that the hydrogen-containing MQ resin and the side vinyl silicone oil completely react.
Comparative example 1
Preparation of modified MQ resin:
compared with example 1, the difference is that the MQ resin is modified by the non-branched vinyl silicone oil: equipped with a stirrer, a thermometer, a condenser and N21500g of vinyl silicone oil and 0.8g of platinum catalyst were added to a three-necked flask in an atmosphere and stirred for 1 hour, 218g of the hydrogen-containing MQ resin prepared in step (1) of example 1 and 220g of xylene were premixed and then slowly added dropwise to the system, and the mixture was heated to 70 ℃ to react for 1 hour. Then closing the heating and stirring system, cooling to room temperature, and then performing adsorption filtration and rotary evaporation on the mixture to obtain the modified MQ resin (the infrared test pattern is shown in figure 8), wherein the M structure isThe value of n is 300. The positions of the groups in fig. 8 are as follows:
Si-CH＝CH2：1500-1600cm-1；Si-CH3：1200-1300cm-1；C-H:2900-3000cm-1；Si-O-Si:1100-1300cm-1(ii) a The comparative example proves that the modified MQ resin product contains Si-CH ═ CH in the structure2，Si-CH3Si-O-Si groups, free of Si-H groups.
The hydrogen content of the product is measured by a hydrogen content measuring method to be 74ppm (the Si-H group content is proved to be extremely low, and the complete reaction can be considered to be 100 ppm), which indicates that the hydrogen-containing MQ resin and the vinyl silicone oil are completely reacted.
Comparative example 2
MDQ resin preparation (linear D mer added directly to MQ resin):
equipped with a stirrer, a thermometer, a condenser and N2Into a three-necked flask in an atmosphere, 208g of tetraethoxysilane, 59g of hexamethyldisiloxane, 5g of divinyltetramethyldisiloxane, and,500g of octamethylcyclotetrasiloxane, 22g of ethanol, 49g of xylene and 0.5g of 98 wt% concentrated sulfuric acid, stirring for 30min, then dropwise adding 50g of water, heating to 85 ℃ to react for 1h after dropwise adding is completed for 25-35 min, heating to distill off ethanol and water, steaming to 130 ℃ of liquid phase temperature, preserving heat for 5 hours, and then cooling to room temperature; extracting with xylene, washing with water until pH is 6.0-7.0, adding anhydrous calcium chloride, drying to obtain clear transparent solution, filtering to remove salt, and rotary steaming to obtain MDQ resin (infrared test pattern is shown in figure 9), wherein M is of structureThe positions of the groups in fig. 9 are as follows:
Si-CH＝CH2：1500-1600cm-1；Si-CH3：1200-1300cm-1；C-H:2900-3000cm-1；Si-O-Si:1100-1300cm-1. The comparative example MDQ resin product structure was confirmed to contain Si-CH ═ CH2，Si-CH3Si-O-Si groups, free of Si-H groups.
No hydrogen content was detected by the hydrogen content measurement method.
[ examples 8 to 14 ]
The modified MQ resins obtained in examples 1 to 7 were used to prepare addition type silicone potting adhesives, and the performance of the addition type silicone potting adhesives was tested, and the results are shown in Table 1.
The specific preparation method of the addition type organic silicon pouring sealant comprises the following steps: respectively adding 210g of modified MQ resin into a stirred kettle, sequentially adding 1g of silane coupling agent A-186, 10g of hydrogen-containing silicone oil, 10g of 1, 1-diphenyl-2-propyne-1-ol, 350g of alumina, 0.1g of platinum catalyst, 2g of surfactant FS-60 and 2g of fumed silica, stirring at a high speed of 3500r/min for 60min, and finally performing vacuum defoaming treatment under the pressure of 0.1MPa to obtain the addition type organic pouring sealant product.
Comparative examples 3 to 4
The resins obtained in comparative examples 1-2 were used to prepare potting adhesives, the preparation methods were the same as in example 8, and the properties were tested, respectively, with the results shown in table 1.
Comparative example 5
Adding 200g of vinyl-terminated silicone oil into 20g of dimethylbenzene solution of 50 wt% vinyl MQ resin, uniformly stirring, carrying out reduced pressure distillation to remove low-boiling-point substances, sequentially adding 1g of silane coupling agent A-186, 10g of hydrogen-containing silicone oil, 10g of 1, 1-diphenyl-2-propyne-1-ol, 350g of alumina, 0.1g of platinum catalyst, 2g of surfactant FS-60 and 2g of fumed silica, stirring at a high speed of 3500r/min, and finally carrying out vacuum defoaming treatment under the pressure of 0.1MPa to obtain a pouring sealant product, and testing the performance of the pouring sealant product, wherein the results are shown in Table 1.
TABLE 1 Property test of pouring sealants prepared in examples and comparative examples
The preparation method can be known that the modified MQ resin prepared by the method belongs to solvent-free liquid MQ resin, the added system does not need to be subjected to reduced pressure distillation to remove low-boiling-point substances, the operation process is simplified, and the environment is protected.
As can be seen from Table 1, when the modified MQ resin prepared by the method of the present invention is added into a system, the oil leakage of the pouring sealant can be effectively improved due to the absence of free silicone oil under the condition that the reinforcing effect is basically unchanged. And because a branched structure is introduced, the viscosity of the base adhesive can be reduced, and the process operation is facilitated.
As can be seen from the comparative examples in Table 1, the modified MQ resin synthesized in the comparative example 1 has a certain improvement on the oil permeability, but the characteristic effect of the branched D structure is still insufficient compared with the examples, and the reinforcement of the pouring sealant is slightly weakened; although the MDQ resin synthesized in comparative example 2 improves the oil leakage to a certain extent by introducing a branched structure, the introduction manner and the introduced D structure damage the Q structure, which does not completely solve the oil leakage problem and greatly reduces the reinforcement of the potting adhesive.
[ test examples ]
The oil permeability and the change in adhesion with time of the addition type silicone prepared in example 8 and the pouring sealant prepared in comparative examples 3 to 5 were respectively measured and are shown in table 2.
Table 2 oil permeability and bonding property change test results of the pouring sealant prepared in example 8 and comparative examples 3-5
As can be seen from table 2, the addition of the modified MQ resin prepared by the method of the present invention to the system can stably improve the oil bleeding problem for a long period of time, and solve the adhesion problem that may occur due to the fracture of the contact surface of the substrate caused by the oil bleeding thereof.
The above description is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, several modifications and additions can be made without departing from the method of the present invention, and these modifications and additions should also be regarded as the protection scope of the present invention.