Preparation method of vinyl MQ silicon resin

Abstract

The invention belongs to the technical field of organic silicon, and particularly relates to a preparation method of vinyl MQ silicon resin, which comprises the following steps: dispersing and hydrolyzing vinyl dimethyl chlorosilane to obtain homogeneous liquid; adding an acid solution into the homogeneous solution, fully stirring, and then blowing at a constant temperature until the volume is unchanged to obtain a reaction precursor solution; the preparation method comprises the following steps: preparing a reaction solution from ethyl silicate and vinyltriethoxysilane; synchronously adding the reaction precursor solution and the pre-reaction solution into a reaction kettle, and stirring at a constant temperature for 20-30 minutes to obtain a reaction solution; and carrying out extraction, washing, rotary evaporation and vacuum drying on the reaction liquid to obtain the vinyl silicone resin. The balance problem of the vinyl MQ silicon resin is solved, vinyl dimethyl chlorosilane and vinyl triethoxy silane are used as raw materials, different silicon atoms are connected to vinyl, and the reaction activity of the vinyl MQ silicon resin and the balance of the reaction activity are improved.

Description

Technical Field

[0001] The present invention belongs to the field of organosilicon technology, and in particular relates to a method for preparing vinyl MQ silicone resin. Background Art

[0002] MQ silicone resin is an organic polysiloxane with a nonlinear structure, which is composed of a tetrafunctional siloxane chain and a monofunctional siloxane chain. Vinyl MQ silicone resin is a type of MQ silicone resin. Vinyl MQ silicone resin has good heat resistance, film-forming properties, adhesion and water repellency. It also has the characteristics of aging resistance and UV resistance. It is widely used in many fields, including defoaming agents, mold release agents, waterproof materials, silicone rubber reinforcement, silicone pressure-sensitive adhesive tackifiers, etc. In actual use, the reactive group of vinyl MQ silicone resin is vinyl, and it reacts through silicon-hydrogen bonds. The distribution of vinyl in vinyl MQ silicone resin will directly affect the connection structure of vinyl MQ silicone resin in the material, that is, the more uniform the distribution of vinyl on MQ silicone resin, the more balanced the performance of vinyl MQ silicone resin. However, there are no reports on balanced vinyl MQ silicone resins. Summary of the invention

[0003] In view of the problems in the prior art, the present invention provides a method for preparing a vinyl MQ silicone resin, which solves the balance problem of the vinyl MQ silicone resin. Vinyl dimethyl chlorosilane and vinyl triethoxysilane are used as raw materials, and different silicon atoms are connected in the vinyl group, thereby improving the reactivity of the vinyl MQ silicone resin and the balance of the reactivity.

[0004] In order to achieve the above technical objectives, the technical solution of the present invention is:

[0005] A method for preparing a vinyl MQ silicone resin comprises the following steps:

[0006] Step 1, adding vinyldimethylsilyl chloride to diethyl ether, dispersing and stirring, then slowly adding ethanol to dissolve, obtaining a vinyldimethylsilyl chloride solution, and finally slowly adding distilled water and dispersing at low temperature by ultrasonic to obtain a homogeneous solution, wherein the concentration of the vinyldimethylsilyl chloride in diethyl ether is 100-200g / L, the stirring speed of the dispersion stirring is 300-500r / min, the amount of the ethanol added is 40-50% of the diethyl ether, the speed of slow addition is 10-20mL / min, the amount of the distilled water added is 60-80% of the mass of the vinyldimethylsilyl chloride, the speed of slow addition is 1-2mL / min, the temperature of the low temperature ultrasonic dispersion is 5-10°C, and the ultrasonic frequency is 70-90kHz; this step is used Using the solubility of vinyldimethylchlorosilane in ether, the vinyldimethylsilane is homogeneously dispersed in ether to form an ether solution, and then the mutual solubility of ether and ethanol is used to stably expand the ether solution to form an ether-ethanol composite solvent; finally, distilled water is added, and the water molecules are quickly dispersed into the entire solvent by controlling the droplet acceleration and the mutual solubility relationship between ethanol and water, in combination with the high-frequency vibration dispersion of low-temperature ultrasound, and directly react with the vinyldimethylchlorosilane in situ to hydrolyze and obtain vinyldimethylhydroxysilane; this expansion method can homogeneously disperse the vinyldimethylchlorosilane, reduce the content per unit area, and fully open the molecular structure, thereby improving the dispersion of the vinyldimethylhydroxysilane and the full opening of the molecular structure of the material;

[0007] Step 2, adding acid solution to the homogenized liquid and stirring fully, then purging at a constant temperature until the volume remains unchanged to obtain a reaction precursor solution, wherein the acid solution uses hydrochloric acid, and the mass fraction of concentrated hydrochloric acid is 30-34%, the amount of the acid solution added is 28-30% of the mass of vinyldimethylsilyl chloride, the stirring speed for sufficient stirring is 100-300r / min, the constant temperature purge uses dry nitrogen at 30-35°C, and the purge speed is 20-30mL / min. This step utilizes the volatility of the ether in the homogenized liquid, and cooperates with the nitrogen purge at 30-35°C to effectively accelerate the volatility of the ether, thereby forming an ethanol aqueous solution of an acidic system;

[0008] Step 3, adding ethyl silicate and vinyl triethoxysilane to ether and stirring evenly, then slowly adding distilled water and ultrasonicating for 20-30 minutes to obtain a pre-reaction solution, wherein the mass ratio of ethyl silicate to vinyl triethoxysilane is 10:1-4, and the mass ratio of ether to ethyl silicate is 15-20:1, the stirring speed for uniform stirring is 100-200r / min, the amount of distilled water added is 1-2% of the volume of ether, the dropping speed is 2-4mL / min, the ultrasonic frequency is 80-100kHz, and the temperature is 5-10°C. This step utilizes the dissolution and dispersion of ethyl silicate and vinyl triethoxysilane in ether, and disperses distilled water into ether by slow dropping and ultrasonic dispersion, and hydrolyzes ethyl silicate and vinyl triethoxysilane in situ;

[0009] Step 4, adding the reaction precursor liquid and the pre-reaction liquid into the reactor simultaneously, and stirring at a constant temperature for 20-30 minutes to obtain a reaction liquid, and recovering the steam to obtain ether liquid, wherein the volume ratio of the reaction precursor liquid to the pre-reaction liquid is 1:3-6, the temperature of the constant temperature stirring is 60-70°C, the time is 3-4h, and the recovered steam is recovered at low temperature to convert the ether vapor into ether liquid, and the temperature of the low temperature recovery is 5-10°C; this step utilizes synchronous addition under constant temperature conditions, and the volume added per unit time is relatively constant, which can ensure continuous reaction, and the molecular weight is controlled by controlling the content in the unit area. At the same time, the ether evaporates at this temperature and is recovered at a low temperature, thereby reducing environmental pressure and realizing recycling;

[0010] Step 5, extracting, washing, rotary evaporating and vacuum drying the reaction solution to obtain vinyl silicone resin, wherein toluene is used for the extraction, the water bath temperature of the rotary evaporation is 80-90°C, the time is 30-60min, and the temperature of the vacuum drying is 80-100°C, and the time is 1-3h; this step uses extraction to remove the solvent and low-boiling substances, thereby obtaining a vinyl MQ silicone resin with higher purity.

[0011] It can be seen from the above description that the present invention has the following advantages:

[0012] 1. The present invention solves the problem of the balance of vinyl MQ silicone resin, uses vinyl dimethyl chlorosilane and vinyl triethoxysilane as raw materials, connects different silicon atoms in the vinyl group, and improves the reactivity of the vinyl MQ silicone resin and the balance of the reactivity.

[0013] 2. The present invention utilizes the pre-reaction liquid and the reaction precursor liquid to form a synchronous addition, and utilizes the contact reaction amount control of the reactants to achieve the effect of molecular weight control, and the molecular weight is relatively concentrated.

[0014] 3. The invention has a simple formula and strong operability, can effectively reduce the production cycle, and can be widely used in industry. At the same time, the vinyl MQ silicone resin prepared by the method has stable performance and high purity. DETAILED DESCRIPTION

[0015] The present invention is described in detail with reference to the embodiments, but no limitation is imposed on the claims of the present invention.

[0016] Example 1

[0017] A method for preparing a vinyl MQ silicone resin comprises the following steps:

[0018] Step 1, adding vinyldimethylchlorosilane to diethyl ether for dispersion and stirring, then slowly adding ethanol to dissolve, obtaining a vinyldimethylchlorosilane solution, and finally slowly adding distilled water and performing low-temperature ultrasonic dispersion to obtain a homogeneous solution, wherein the concentration of the vinyldimethylchlorosilane in diethyl ether is 100 g / L, the stirring speed of the dispersion and stirring is 300 r / min, the amount of the ethanol added is 40% of the diethyl ether, the speed of slow dripping is 10 mL / min, the amount of the distilled water added is 60% of the mass of the vinyldimethylchlorosilane, the speed of slow dripping is 1 mL / min, the temperature of the low-temperature ultrasonic dispersion is 5° C., and the ultrasonic frequency is 70 kHz;

[0019] Step 2, adding the acid solution to the homogenized liquid and stirring it fully, and then purging it at a constant temperature until the volume remains unchanged to obtain a reaction precursor solution, wherein the acid solution uses hydrochloric acid, and the mass fraction of concentrated hydrochloric acid is 30%, the amount of the acid solution added is 28% of the mass of vinyldimethylsilyl chloride, the stirring speed of the sufficient stirring is 100r / min, the constant temperature purging uses dry nitrogen at 30°C, and the purging speed is 20mL / min;

[0020] Step 3, adding ethyl silicate and vinyl triethoxysilane to ether and stirring evenly, then slowly dropping distilled water and ultrasonicating for 20 minutes to obtain a pre-reaction liquid, wherein the mass ratio of ethyl silicate to vinyl triethoxysilane is 10:1, and the mass ratio of ether to ethyl silicate is 15:1, the stirring speed for stirring evenly is 100 r / min, the amount of distilled water added is 1% of the volume of ether, the dropping speed is 2 mL / min, the ultrasonic frequency is 80 kHz, and the temperature is 5°C;

[0021] Step 4, adding the reaction precursor liquid and the pre-reaction liquid into the reactor simultaneously, and stirring at a constant temperature for 20 minutes to obtain a reaction liquid, and recovering the steam to obtain ether liquid, the volume ratio of the reaction precursor liquid to the pre-reaction liquid is 1:3, the temperature of the constant temperature stirring is 60° C., the time is 3 hours, and the recovered steam adopts a low-temperature recovery method to convert the ether vapor into ether liquid, and the low-temperature recovery temperature is 5° C.;

[0022] Step 5, extracting, washing, rotary evaporating and vacuum drying the reaction solution to obtain vinyl silicone resin, wherein toluene is used for the extraction, the water bath temperature of the rotary evaporation is 80° C., the time is 30 minutes, and the temperature of the vacuum drying is 80° C., and the time is 1 hour.

[0023] Example 2

[0024] A method for preparing a vinyl MQ silicone resin comprises the following steps:

[0025] Step 1, adding vinyldimethylchlorosilane to diethyl ether for dispersion and stirring, then slowly adding ethanol to dissolve, obtaining a vinyldimethylchlorosilane solution, and finally slowly adding distilled water and performing low-temperature ultrasonic dispersion to obtain a homogeneous solution, wherein the concentration of the vinyldimethylchlorosilane in diethyl ether is 200 g / L, the stirring speed of the dispersion and stirring is 500 r / min, the amount of the ethanol added is 50% of the diethyl ether, the speed of the slow addition is 20 mL / min, the amount of the distilled water added is 80% of the mass of the vinyldimethylchlorosilane, the speed of the slow addition is 2 mL / min, the temperature of the low-temperature ultrasonic dispersion is 10° C., and the ultrasonic frequency is 90 kHz;

[0026] Step 2, adding the acid solution to the homogenized liquid and stirring it fully, and then purging it at a constant temperature until the volume remains unchanged to obtain a reaction precursor solution, wherein the acid solution uses hydrochloric acid, and the mass fraction of concentrated hydrochloric acid is 34%, the amount of the acid solution added is 30% of the mass of vinyldimethylsilyl chloride, the stirring speed of the sufficient stirring is 300r / min, and the constant temperature purging uses dry nitrogen at 35°C, and the purging speed is 30mL / min;

[0027] Step 3, adding ethyl silicate and vinyl triethoxysilane to diethyl ether and stirring evenly, then slowly adding distilled water and ultrasonicating for 30 minutes to obtain a pre-reaction liquid, wherein the mass ratio of ethyl silicate to vinyl triethoxysilane is 5:2, and the mass ratio of diethyl ether to ethyl silicate is 20:1, the stirring speed for stirring evenly is 200r / min, the amount of distilled water added is 2% of the volume of diethyl ether, the dropping speed is 4mL / min, the ultrasonic frequency is 100kHz, and the temperature is 10°C;

[0028] Step 4, adding the reaction precursor liquid and the pre-reaction liquid into the reactor simultaneously, and stirring at a constant temperature for 30 minutes to obtain a reaction liquid, and recovering the steam to obtain ether liquid, the volume ratio of the reaction precursor liquid to the pre-reaction liquid is 1:6, the temperature of the constant temperature stirring is 70°C, the time is 4 hours, and the recovered steam adopts a low-temperature recovery method to convert the ether vapor into ether liquid, and the low-temperature recovery temperature is 10°C;

[0029] Step 5, extracting, washing, rotary evaporating and vacuum drying the reaction solution to obtain vinyl silicone resin, wherein toluene is used for the extraction, the water bath temperature of the rotary evaporation is 90° C., the time is 60 min, and the temperature of the vacuum drying is 100° C., and the time is 3 h.

[0030] Example 3

[0031] A method for preparing a vinyl MQ silicone resin comprises the following steps:

[0032] Step 1, adding vinyldimethylsilyl chloride to diethyl ether and dispersing and stirring, then slowly adding ethanol to dissolve, obtaining a vinyldimethylsilyl chloride solution, and finally slowly adding distilled water and performing low-temperature ultrasonic dispersion to obtain a homogeneous solution, wherein the concentration of the vinyldimethylsilyl chloride in diethyl ether is 150 g / L, the stirring speed of the dispersion stirring is 400 r / min, the amount of the ethanol added is 45% of the diethyl ether, the speed of the slow addition is 15 mL / min, the amount of the distilled water added is 70% of the mass of the vinyldimethylsilyl chloride, the speed of the slow addition is 2 mL / min, the temperature of the low-temperature ultrasonic dispersion is 8° C., and the ultrasonic frequency is 80 kHz;

[0033] Step 2, adding the acid solution to the homogenized liquid and stirring it fully, and then purging it at a constant temperature until the volume remains unchanged to obtain a reaction precursor solution, wherein the acid solution uses hydrochloric acid, and the mass fraction of concentrated hydrochloric acid is 33%, the amount of the acid solution added is 29% of the mass of vinyldimethylsilyl chloride, the stirring speed of the sufficient stirring is 200r / min, the constant temperature purging uses dry nitrogen at 33°C, and the purging speed is 25mL / min;

[0034] Step 3, adding ethyl silicate and vinyl triethoxysilane to diethyl ether and stirring evenly, then slowly adding distilled water and ultrasonicating for 25 minutes to obtain a pre-reaction solution, wherein the mass ratio of ethyl silicate to vinyl triethoxysilane is 10:3, and the mass ratio of diethyl ether to ethyl silicate is 18:1, the stirring speed for stirring evenly is 150r / min, the amount of distilled water added is 1-2% of the volume of diethyl ether, the dropping speed is 3mL / min, the ultrasonic frequency is 90kHz, and the temperature is 8°C;

[0035] Step 4, adding the reaction precursor liquid and the pre-reaction liquid into the reactor simultaneously, and stirring at a constant temperature for 25 minutes to obtain a reaction liquid, and recovering the steam to obtain ether liquid, the volume ratio of the reaction precursor liquid to the pre-reaction liquid is 1:5, the temperature of the constant temperature stirring is 65°C, the time is 4 hours, and the recovered steam adopts a low-temperature recovery method to convert the ether vapor into ether liquid, and the low-temperature recovery temperature is 8°C;

[0036] Step 5, extracting, washing, rotary evaporating and vacuum drying the reaction solution to obtain vinyl silicone resin, wherein toluene is used for the extraction, the water bath temperature of the rotary evaporation is 85° C., the time is 50 min, and the temperature of the vacuum drying is 90° C., and the time is 2 h.

[0037] Comparative Example 1

[0038] A method for preparing a vinyl MQ silicone resin comprises the following steps:

[0039] Step 1, adding vinyldimethylsilyl chloride to diethyl ether and dispersing and stirring, then slowly adding ethanol to dissolve, obtaining a vinyldimethylsilyl chloride solution, and finally slowly adding distilled water and performing low-temperature ultrasonic dispersion to obtain a homogeneous solution, wherein the concentration of the vinyldimethylsilyl chloride in diethyl ether is 150 g / L, the stirring speed of the dispersion stirring is 400 r / min, the amount of the ethanol added is 45% of the diethyl ether, the speed of the slow addition is 15 mL / min, the amount of the distilled water added is 70% of the mass of the vinyldimethylsilyl chloride, the speed of the slow addition is 2 mL / min, the temperature of the low-temperature ultrasonic dispersion is 8° C., and the ultrasonic frequency is 80 kHz;

[0040] Step 2, adding the acid solution to the homogenized liquid and stirring it fully, and then purging it at a constant temperature until the volume remains unchanged to obtain a reaction precursor solution, wherein the acid solution uses hydrochloric acid, and the mass fraction of concentrated hydrochloric acid is 33%, the amount of the acid solution added is 29% of the mass of vinyldimethylsilyl chloride, the stirring speed of the sufficient stirring is 200r / min, the constant temperature purging uses dry nitrogen at 33°C, and the purging speed is 25mL / min;

[0041] Step 3, adding ethyl silicate to ether and stirring evenly, then slowly dropping distilled water and ultrasonicating for 25 minutes to obtain a pre-reaction solution, wherein the mass ratio of ether to ethyl silicate is 18:1, the stirring speed for stirring evenly is 150r / min, the amount of distilled water added is 1-2% of the volume of ether, the dropping speed is 3mL / min, the ultrasonic frequency is 90kHz, and the temperature is 8°C;

[0042] Step 4, adding the reaction precursor liquid and the pre-reaction liquid into the reactor simultaneously, and stirring at a constant temperature for 25 minutes to obtain a reaction liquid, and recovering the steam to obtain ether liquid, the volume ratio of the reaction precursor liquid to the pre-reaction liquid is 1:5, the temperature of the constant temperature stirring is 65°C, the time is 4 hours, and the recovered steam adopts a low-temperature recovery method to convert the ether vapor into ether liquid, and the low-temperature recovery temperature is 8°C;

[0043] Step 5, extracting, washing, rotary evaporating and vacuum drying the reaction solution to obtain vinyl silicone resin, wherein toluene is used for the extraction, the water bath temperature of the rotary evaporation is 85° C., the time is 50 min, and the temperature of the vacuum drying is 90° C., and the time is 2 h.

[0044] Comparative Example 2

[0045] Comparative Example 2 uses commercially available vinyl MQ silicone resin, selected from Wuhan Lanabai Pharmaceutical Chemical Co., Ltd.

[0046] Performance Testing

[0047] The products of Examples 1-3 and Comparative Examples 1-2 were used as test samples for performance testing, and the results are as follows:

[0048] Table 1 Performance test of vinyl MQ silicone resin

[0049]

[0050] Comparison of the data of the above-mentioned Examples 1-3 and Comparative Examples 1-2 shows that the present technical solution utilizes vinyldimethylchlorosilane and vinyltriethoxysilane to increase the content of vinyl, and vinyldimethylchlorosilane and vinyltriethoxysilane are added in different processes to ensure the uniform distribution of vinyl, and exhibit excellent flexibility, reactivity and film-forming properties in the subsequent use of silicone rubber. At the same time, the resin purity of the present technical solution reaches more than 99%, which is slightly higher than the product of Wuhan Lanabai Pharmaceutical Chemical Co., Ltd.

[0051] It is understood that the above specific description of the present invention is only used to illustrate the present invention and is not limited to the technical solutions described in the embodiments of the present invention. Those skilled in the art should understand that the present invention can still be modified or replaced by equivalents to achieve the same technical effects; as long as the use requirements are met, they are within the protection scope of the present invention.

Claims

1. A method for preparing a vinyl MQ silicone resin, characterized in that: The steps include: Step 1, adding vinyldimethylsilyl chloride to ether and dispersing and stirring, then slowly adding ethanol to dissolve, to obtain a vinyldimethylsilyl chloride solution, and finally slowly adding distilled water and dispersing by low temperature ultrasonication, to obtain a homogeneous solution; Step 2, adding the acid solution to the homogenized liquid and stirring thoroughly, and then blowing at a constant temperature until the volume remains unchanged to obtain a reaction precursor solution; Step 3, adding ethyl silicate and vinyl triethoxysilane to diethyl ether and stirring evenly, then slowly adding distilled water and ultrasonicating for 20-30 minutes to obtain a pre-reaction solution; Step 4, adding the reaction precursor liquid and the pre-reaction liquid into the reactor simultaneously, and stirring at a constant temperature for 20-30 minutes to obtain a reaction liquid, and recovering the steam to obtain an ether liquid; Step 5, extracting, washing, rotary evaporating and vacuum drying the reaction solution to obtain vinyl silicone resin.

2. The method for preparing vinyl MQ silicone resin according to claim 1, characterized in that: The concentration of vinyldimethylsilyl chloride in diethyl ether in step 1 is 100-200 g / L, the stirring speed of the dispersion stirring is 300-500 r / min, the amount of ethanol added is 40-50% of the diethyl ether, and the speed of slow dripping is 10-20 mL / min.

3. The method for preparing the vinyl MQ silicone resin according to claim 1, characterized in that: The amount of distilled water added in step 1 is 60-80% of the mass of vinyldimethylchlorosilane, the speed of slow dripping is 1-2 mL / min, the temperature of low-temperature ultrasonic dispersion is 5-10° C., and the ultrasonic frequency is 70-90 kHz.

4. The method for preparing the vinyl MQ silicone resin according to claim 1, characterized in that: The acid solution in step 2 is hydrochloric acid, and the mass fraction of concentrated hydrochloric acid is 30-34%. The amount of the acid solution added is 28-30% of the mass of vinyldimethylchlorosilane, and the stirring speed for sufficient stirring is 100-300r / min.

5. The method for preparing the vinyl MQ silicone resin according to claim 1, characterized in that: The constant temperature purging in step 2 uses dry nitrogen at 30-35° C., and the purging speed is 20-30 mL / min.

6. The method for preparing the vinyl MQ silicone resin according to claim 1, characterized in that: The mass ratio of ethyl silicate to vinyl triethoxysilane in step 3 is 10:1-4, and the mass ratio of ether to ethyl silicate is 15-20:1, and the stirring speed for uniform stirring is 100-200 r / min.

7. The method for preparing the vinyl MQ silicone resin according to claim 1, characterized in that: The amount of distilled water added in step 3 is 1-2% of the volume of ether, the dropping speed is 2-4 mL / min, the frequency of ultrasound is 80-100 kHz, and the temperature is 5-10° C.

8. The method for preparing the vinyl MQ silicone resin according to claim 1, characterized in that: The volume ratio of the reaction precursor solution to the pre-reaction solution in step 4 is 1:3-6, the temperature of constant temperature stirring is 60-70° C., and the time is 3-4 hours.

9. The method for preparing the vinyl MQ silicone resin according to claim 1, characterized in that: The recovered steam in step 4 is recovered at low temperature to convert the ether vapor into ether liquid, and the temperature of the low temperature recovery is 5-10°C.

10. The method for preparing the vinyl MQ silicone resin according to claim 1, characterized in that: The extraction in step 5 uses toluene, the water bath temperature of the rotary evaporation is 80-90°C, the time is 30-60min, and the temperature of the vacuum drying is 80-100°C, the time is 1-3h.

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