CN103304818A - Preparation method of methyl phenyl silicone oil - Google Patents

Abstract

The invention relates to a preparation method of methylphenyl silicone oil, which belongs to the technical field of organosilicon synthesis. The method is to add a certain proportion of dimethyldichlorosilane and diphenyldichlorosilane monomers into a mixed solvent of xylene and acetone and mix evenly, and then add a mixed hydrolyzate of acetone and water dropwise to it by reverse hydrolysis method, After the dropwise addition, a certain amount of end-capping agent was added, and the reaction was continued for a period of time at 30° C., and the hydrolysis was completed. Stand for stratification, separate the lower layer of acid water, and wash the upper layer of hydrolyzate with hot distilled water until neutral to obtain a siloxane prepolymer, add a certain amount of condensation catalyst to it for condensation reaction, wash off the catalyst with hot distilled water to neutrality, and then distill off the solvent xylene and low boilers under reduced pressure to obtain methyl phenyl silicone oil products. The methylphenyl silicone oil prepared by the invention is a clear translucent oily liquid, has good product uniformity, high purity, simple preparation process conditions, recyclable solvent and is easy for industrialized production.

Description

A kind of preparation method of methylphenyl silicone oil

Technical field:

The invention relates to a method for preparing silicone oil, in particular to a method for preparing trimethylsiloxane-terminated dimethyldiphenyl silicone oil. The product is a clear translucent oily liquid with good uniformity and high purity.

Background technique:

Silicone oil usually refers to a linear polysiloxane that maintains a liquid state at room temperature. The organic groups of the most commonly used silicone oil are all methyl, called methyl silicone oil, and methyl phenyl silicone oil is part of the methyl group in methyl silicone oil that is covered with benzene. The products substituted with radicals have excellent high and low temperature resistance, lubricity and radiation resistance, and are products with broad development prospects.

At present, there are many preparation methods for methylphenyl silicone oil. For example, patent CN 102070785A discloses a method of using methylphenyldichlorosilane hydrolyzate, dimethyldichlorosilane hydrolyzate, methylphenylcyclosiloxane Alkane is the method for preparing hydroxyl-terminated polymethylphenylsiloxane as raw material; Patent CN 101851333A discloses a method of using methylphenylcyclosiloxane, dimethylcyclosiloxane, methylhydrogencyclosiloxane As raw material, rare earth super acid is used as catalyst to prepare methyl phenyl hydrogen-containing silicone oil. The above method mainly uses cyclosiloxane as a raw material to prepare methylphenyl silicone oil, which increases the cost of product preparation and is not conducive to industrial production. Patent CN 102516546A discloses a kind of using methylphenyl dichlorosilane as raw material and weak organic alkali aqueous solution as acid-binding agent to prepare low-viscosity methylphenyl hydroxy silicone oil. Although the raw material is cheap, a large amount of weak organic Alkali increases the cost of industrialized production.

Invention content:

The present invention proposes a method for preparing methylphenyl silicone oil, specifically a method for preparing trimethylsiloxane-terminated dimethyldiphenyl silicone oil. The method has simple process, mild reaction conditions, and easy raw materials. The invention has the advantages of low cost and easy industrial production.

The present invention is achieved through the following technical solutions:

A preparation method of methyl phenyl silicone oil is characterized in that it is carried out in the following steps:

(1) Add 5.06 to 35.45 g of diphenyldichlorosilane, 80 mL of xylene, and 50 mL of acetone for every 7.74 to 23.23 g of dimethyldichlorosilane in a 500 mL three-necked flask, and stir and mix evenly at 30 °C; Use acetone and distilled water to prepare the hydrolyzate. The dosage of acetone and distilled water is to add 100 mL of acetone and 57.6 g of dichlorosilane for every 7.74~23.23g of dimethyldichlorosilane and 5.06~35.45g of diphenyldichlorosilane, stir well, and use The constant pressure titration funnel was added drop by drop to the three-necked flask, and the dropping rate was controlled to keep 1d/2s. After the dropwise addition, a certain amount of end-capping agent was added, and the reaction was continued at 30°C for 5 h, and the hydrolysis was completed;

(2) Stand for stratification, separate the lower layer of acid water, and wash the upper layer of hydrolyzate with distilled water at 50-60 °C until neutral to obtain a siloxane prepolymer, and then add a condensation catalyst at 80-120 °C for condensation reaction 1 to 8 hours, after the reaction is over, wash the catalyst with distilled water at 50 to 60 °C until neutral, and then under reduced pressure at 130 °C

The solvent xylene and low boilers are distilled off to obtain methylphenyl silicone oil product.

Wherein the amount of dimethyl dichlorosilane and diphenyl dichlorosilane added in the step (1) is: the total molar weight of dimethyl dichlorosilane and diphenyl dichlorosilane is 0.2 mol, dimethyl dichlorosilane The mass ratio of chlorosilane and diphenyldichlorosilane is preferably 18.07:15.19;

Wherein the capping agent described in the step (1) is trimethylchlorosilane, and the addition amount is: the total molar ratio of trimethylchlorosilane to dimethyldichlorosilane and diphenyldichlorosilane is 1:10 ~1:80, 0.2716~2.1728 g;

Wherein step (2) when adding a condensation catalyst to carry out the condensation reaction, the amount of the condensation catalyst added is 0.01% to 0.2% of the total mass of dimethyldichlorosilane and diphenyldichlorosilane, which is 0.0133 g to 0.2660 g;

Wherein the condensation catalyst described in step (2) is the ethanolic solution of 25wt% sodium ethylate;

Wherein the optimal reaction temperature of the catalyst condensation reaction described in step (2) is 100° C., and the optimal condensation reaction time is 3 hours.

The advantages of the present invention are:

1. The raw material used in the present invention is chlorosilane monomer, which is simple, can be produced by direct method, has large output, low cost, and is easy to obtain, which makes industrial production of methylphenyl silicone oil easier, and at the same time, the process is simple and the reaction conditions are mild; The solvent xylene can be recovered and reused by vacuum distillation.

2. The present invention uses a strong base, sodium ethoxide, as a catalyst with a small dosage, which can effectively catalyze the condensation of siloxane prepolymers to prepare methylphenyl silicone oil.

3. The silicone oil synthesized by the present invention is a clear translucent oily liquid with small molecular weight distribution, good uniformity and high purity.

4. The present invention produces a large amount of waste hydrochloric acid during the hydrolysis of chlorosilane, which can be mixed with bauxite, and the supernatant liquid is heated and evaporated to obtain aluminum chloride crystals, which are used as water purifiers to achieve the effect of comprehensive recycling and reduce environmental pollution.

Description of drawings

Figure 1 is the GPC spectrum of methylphenyl silicone oil prepared when the Ph/R ratio is 0.1.

Fig. 2 is the infrared spectrogram of methylphenyl silicone oil prepared when the Ph/R ratio is 0.3.

Figure 3 is the GPC spectrum of methylphenyl silicone oil prepared when the Ph/R ratio is 0.3.

Detailed ways:

The following are preferred embodiments of the present invention, which can better understand the present invention, but the embodiments of the present invention are not limited thereto, and the data shown therein do not represent limitations to the scope of the present invention.

Example 1

The Ph/R ratio (molar ratio) was 0.1. Add 80 mL of xylene, 50 mL of acetone, 23.23 g of dimethyldichlorosilane and 5.06 g of diphenyldichlorosilane into a 500 mL three-neck flask, stir and mix evenly at 30 °C; configure a certain proportion of hydrolyzate, of which Acetone 100 mL and distilled water 57.6 g, stir evenly, add drop by drop to the three-necked flask with a constant pressure titration funnel, control the dropping speed to keep 1d/2s, the total titration time is about 3 h, add 0.5432 g capping after the dropwise addition Chlorotrimethylsilane, continue to react at 30°C for 5h, and the hydrolysis is completed; stand for stratification, separate the lower layer of acid water, wash the upper layer of hydrolyzate with distilled water at 50-60°C until neutral, and obtain a siloxane prepolymer , and then add 0.0570 g of condensation catalyst sodium ethylate (0.05% of the total monomer mass) at 100 °C for condensation reaction for 3 h. After the reaction, wash the catalyst with 50-60 °C distilled water to neutrality, and then The solvent xylene and low boilers were distilled off under reduced pressure to obtain a clear translucent liquid methyl phenyl silicone oil product. Its GPC spectrum is shown in Figure 1. Its GPC spectrum shows a single-peak dispersion mode, and the silicone oil has good uniformity, high purity and small molecular weight distribution.

Example 2

The Ph/R ratio (molar ratio) was 0.3. Add 80 mL of xylene, 50 mL of acetone, 18.07 g of dimethyldichlorosilane and 15.19 g of diphenyldichlorosilane into a 500 mL three-necked flask, and stir and mix evenly at 30 °C; prepare a certain proportion of hydrolyzate, of which Acetone 100 mL and distilled water 57.6 g, stir evenly, add drop by drop to the three-necked flask with a constant pressure titration funnel, control the dropping rate to keep 1d/2s, the total titration time is about 3 h, add 0.5432 g capped Chlorotrimethylsilane, continue to react at 30°C for 5h, and the hydrolysis is completed; stand for stratification, separate the lower layer of acid water, wash the upper layer of hydrolyzate with distilled water at 50-60°C until neutral, and obtain a siloxane prepolymer , and then add 0.0665 g of condensation catalyst sodium ethylate (0.05% of the total monomer mass) at 100 °C for condensation reaction for 3 h. The solvent xylene and low boilers were distilled off under reduced pressure to obtain a clear translucent liquid methyl phenyl silicone oil product. Its infrared spectrogram is shown in Figure 2, and its GPC spectrum is shown in Figure 3. In its infrared spectrum, the absorption peaks at 3051.6 cm ^-1 and 3071.1 cm ^-1 belong to the stretching vibration absorption of phenyl unsaturated hydrogen; the absorption peaks at 2962.2 and 2904.2 are CH stretching vibration peaks in CH ₃ -Si; at 1429.7 cm The strong absorption peak ^{of -1} is attributed to the vibration absorption peak of the aromatic ring in Si-Ph; the sharp absorption peak at 1261.4 is the absorption peak of Si-CH ₃ ; there is a broad and strong absorption band at 1000-1120 cm ^-1 Attributed to the antisymmetric stretching vibration of Si-O-Si. Its GPC spectrum shows a single-peak dispersion mode, and the silicone oil has good uniformity, high purity and small molecular weight distribution.

Example 3

The Ph/R ratio (molar ratio) was 0.7. Add 80 mL of xylene, 50 mL of acetone, 7.74 g of dimethyldichlorosilane, and 35.45 g of diphenyldichlorosilane into a 500 mL three-neck flask, stir and mix evenly at 30 °C; configure a certain proportion of hydrolyzate, of which Acetone 100 mL and distilled water 57.6 g, stir evenly, add drop by drop to the three-necked flask with a constant pressure titration funnel, control the dropping speed to keep 1d/2s, the total titration time is about 3 h, add 0.5432 g capping after the dropwise addition Chlorotrimethylsilane, continue to react at 30°C for 5 hours, and the hydrolysis is completed; stand for stratification, separate the lower layer of acid water, wash the upper layer of hydrolyzate with distilled water at 50-60°C until neutral, and obtain a siloxane prepolymer , and then add 0.0864 g of condensation catalyst sodium ethylate (0.05% of the total mass of the monomer) at 100 °C for condensation reaction for 3 h. The solvent xylene and low boilers were distilled off under reduced pressure to obtain a white soft methyl phenyl silicone oil product.

Example 4

The Ph/R ratio (molar ratio) was 0.3. Add 80 mL of xylene, 50 mL of acetone, 18.07 g of dimethyldichlorosilane, and 15.19 g of diphenyldichlorosilane into a 500 mL three-neck flask, stir and mix evenly at 30 °C; configure a certain proportion of hydrolyzate, of which Acetone 100 mL and distilled water 57.6 g, stir evenly, add drop by drop to the three-necked flask with a constant pressure titration funnel, control the dropping speed to keep 1d/2s, the total titration time is about 3 h, add 2.1728 g capping after the dropwise addition Chlorotrimethylsilane, continue to react at 30°C for 5 hours, and the hydrolysis is completed; stand for stratification, separate the lower layer of acid water, wash the upper layer of hydrolyzate with distilled water at 50-60°C until neutral, and obtain a siloxane prepolymer , and then add 0.0665 g of condensation catalyst sodium ethylate (the mass is 0.05% of the total mass of the monomer) at 100 °C for condensation reaction for 3 h. The solvent xylene and low boilers were distilled off under reduced pressure to obtain a clear translucent liquid methyl phenyl silicone oil product.

Example 5

The Ph/R ratio (molar ratio) was 0.3. Add 80 mL of xylene, 50 mL of acetone, 18.07 g of dimethyldichlorosilane, and 15.19 g of diphenyldichlorosilane into a 500 mL three-neck flask, stir and mix evenly at 30 °C; configure a certain proportion of hydrolyzate, of which Acetone 100 mL and distilled water 57.6 g, stir evenly, add drop by drop to the three-necked flask with a constant pressure titration funnel, control the dropping speed to keep 1d/2s, the total titration time is about 3 h, add 0.2716 g capping after the dropwise addition Chlorotrimethylsilane, continue to react at 30°C for 5 hours, and the hydrolysis is completed; stand for stratification, separate the lower layer of acid water, wash the upper layer of hydrolyzate with distilled water at 50-60°C until neutral, and obtain a siloxane prepolymer , and then add 0.0665 g of condensation catalyst sodium ethylate (the mass is 0.05% of the total mass of the monomer) at 100 °C for condensation reaction for 3 h. The solvent xylene and low boilers were distilled off under reduced pressure to obtain a clear translucent liquid methyl phenyl silicone oil product.

Example 6

The Ph/R ratio (molar ratio) was 0.3. Add 80 mL of xylene, 50 mL of acetone, 18.07 g of dimethyldichlorosilane, and 15.19 g of diphenyldichlorosilane into a 500 mL three-neck flask, stir and mix evenly at 30 °C; configure a certain proportion of hydrolyzate, of which Acetone 100 mL and distilled water 57.6 g, stir evenly, add drop by drop to the three-necked flask with a constant pressure titration funnel, control the dropping speed to keep 1d/2s, the total titration time is about 3 h, add 0.5432 g capping after the dropwise addition Chlorotrimethylsilane, continue to react at 30°C for 5 hours, and the hydrolysis is completed; stand for stratification, separate the lower layer of acid water, wash the upper layer of hydrolyzate with distilled water at 50-60°C until neutral, and obtain a siloxane prepolymer , and then add 0.0665 g of condensation catalyst sodium ethylate (0.05% of the total mass of the monomer) at 100 °C for condensation reaction for 1 h. The solvent xylene and low boilers were distilled off under reduced pressure to obtain a clear translucent liquid methyl phenyl silicone oil product.

Example 7

The Ph/R ratio (molar ratio) was 0.3. Add 80 mL of xylene, 50 mL of acetone, 18.07 g of dimethyldichlorosilane, and 15.19 g of diphenyldichlorosilane into a 500 mL three-neck flask, stir and mix evenly at 30 °C; configure a certain proportion of hydrolyzate, of which Acetone 100 mL and distilled water 57.6 g, stir evenly, add drop by drop to the three-necked flask with a constant pressure titration funnel, control the dropping speed to keep 1d/2s, the total titration time is about 3 h, add 0.5432 g capping after the dropwise addition Chlorotrimethylsilane, continue to react at 30°C for 5 hours, and the hydrolysis is completed; stand for stratification, separate the lower layer of acid water, wash the upper layer of hydrolyzate with distilled water at 50-60°C until neutral, and obtain a siloxane prepolymer , and then add 0.0665 g of condensation catalyst sodium ethylate (the mass is 0.05% of the total mass of the monomer) at 100 °C for condensation reaction for 8 h. The solvent xylene and low boilers were distilled off under reduced pressure to obtain a yellow translucent liquid methyl phenyl silicone oil product.

Example 8

The Ph/R ratio (molar ratio) was 0.3. Add 80 mL of xylene, 50 mL of acetone, 18.07 g of dimethyldichlorosilane, and 15.19 g of diphenyldichlorosilane into a 500 mL three-neck flask, stir and mix evenly at 30 °C; configure a certain proportion of hydrolyzate, of which Acetone 100 mL and distilled water 57.6 g, stir evenly, add drop by drop to the three-necked flask with a constant pressure titration funnel, control the dropping speed to keep 1d/2s, the total titration time is about 3 h, add 0.5432 g capping after the dropwise addition Chlorotrimethylsilane, continue to react at 30°C for 5 hours, and the hydrolysis is completed; stand for stratification, separate the lower layer of acid water, wash the upper layer of hydrolyzate with distilled water at 50-60°C until neutral, and obtain a siloxane prepolymer , and then add 0.0665 g of condensation catalyst sodium ethylate (the mass is 0.05% of the total mass of the monomer) at 80 °C for condensation reaction for 3 h. The solvent xylene and low boilers were distilled off under reduced pressure to obtain a clear translucent liquid methyl phenyl silicone oil product.

Example 9

The Ph/R ratio (molar ratio) was 0.3. Add 80 mL of xylene, 50 mL of acetone, 18.07 g of dimethyldichlorosilane, and 15.19 g of diphenyldichlorosilane into a 500 mL three-neck flask, stir and mix evenly at 30 °C; configure a certain proportion of hydrolyzate, of which Acetone 100 mL and distilled water 57.6 g, stir evenly, add drop by drop to the three-necked flask with a constant pressure titration funnel, control the dropping speed to keep 1d/2s, the total titration time is about 3 h, add 0.5432 g capping after the dropwise addition Chlorotrimethylsilane, continue to react at 30°C for 5 hours, and the hydrolysis is completed; stand for stratification, separate the lower layer of acid water, wash the upper layer of hydrolyzate with distilled water at 50-60°C until neutral, and obtain a siloxane prepolymer , and then add 0.0665 g of condensation catalyst sodium ethylate (0.05% of the total mass of the monomer) at 120 °C for condensation reaction for 3 h. The solvent xylene and low boilers were distilled off under reduced pressure to obtain a yellow translucent liquid methyl phenyl silicone oil product.

Example 10

The Ph/R ratio (molar ratio) was 0.3. Add 80 mL of xylene, 50 mL of acetone, 18.07 g of dimethyldichlorosilane, and 15.19 g of diphenyldichlorosilane into a 500 mL three-neck flask, stir and mix evenly at 30 °C; configure a certain proportion of hydrolyzate, of which Acetone 100 mL and distilled water 57.6 g, stir evenly, add drop by drop to the three-necked flask with a constant pressure titration funnel, control the dropping speed to keep 1d/2s, the total titration time is about 3 h, add 0.5432 g capping after the dropwise addition Chlorotrimethylsilane, continue to react at 30°C for 5 hours, and the hydrolysis is completed; stand for stratification, separate the lower layer of acid water, wash the upper layer of hydrolyzate with distilled water at 50-60°C until neutral, and obtain a siloxane prepolymer , and then add 0.0133 g of condensation catalyst sodium ethylate (0.01% of the total mass of the monomer) at 100 °C for condensation reaction for 3 h. The solvent xylene and low boilers were distilled off under reduced pressure to obtain a clear translucent liquid methyl phenyl silicone oil product.

Example 11

The Ph/R ratio (molar ratio) was 0.3. Add 80 mL of xylene, 50 mL of acetone, 18.07 g of dimethyldichlorosilane, and 15.19 g of diphenyldichlorosilane into a 500 mL three-neck flask, stir and mix evenly at 30 °C; configure a certain proportion of hydrolyzate, of which Acetone 100 mL and distilled water 57.6 g, stir evenly, add drop by drop to the three-necked flask with a constant pressure titration funnel, control the dropping speed to keep 1d/2s, the total titration time is about 3 h, add 0.5432 g capping after the dropwise addition Chlorotrimethylsilane, continue to react at 30°C for 5 hours, and the hydrolysis is completed; stand for stratification, separate the lower layer of acid water, wash the upper layer of hydrolyzate with distilled water at 50-60°C until neutral, and obtain a siloxane prepolymer , and then add 0.2660 g of condensation catalyst sodium ethylate (the mass is 0.2% of the total mass of the monomer) at 100 °C for condensation reaction for 3 h. The solvent xylene and low boilers were distilled off under reduced pressure to obtain a yellow translucent liquid methyl phenyl silicone oil product.

Claims (6)

1. the preparation method of a methyl phenyl silicone oil, carry out in the steps below:

(1) in there-necked flask, adds 5.06～35.45 g diphenyl dichlorosilanes, 80 mL dimethylbenzene, 50 mL acetone by per 7.74 ~ 23.23 g dimethyldichlorosilane(DMCS)s, under 30 ℃, mix; With acetone and distilled water configuration hydrolyzed solution, the consumption of acetone and distilled water is for to add 100 mL acetone and 57.6 g distilled water by per 7.74 ~ 23.23g dimethyldichlorosilane(DMCS) and 5.06～35.45 g diphenyl dichlorosilanes, stir, dropwise drip in there-necked flask with constant voltage titration funnel, the control rate of addition keeps 1d/2s, dropwise a certain amount of end-capping reagent of rear adding, at 30 ℃ of lower reaction 5 h that continue, hydrolysis finishes;

(2) standing demix, tell lower floor's sour water, the upper strata hydrolyzate is washed till neutrality with 50～60 ℃ distilled water, obtain siloxane prepolymer, then carry out condensation reaction 1～8 h at 80～120 ℃ of lower condensation catalysts that add, after reaction finishes, extremely neutral with 50～60 ℃ distilled water flush away catalyzer, then 130 ℃ of reduced pressure

Under steam solvent xylene and low-boiling-point substance, obtain the methyl phenyl silicone oil product.

2. the preparation method of methyl phenyl silicone oil according to claim 1, it is characterized in that, the dimethyldichlorosilane(DMCS) that wherein adds in the step (1), the amount of diphenyl dichlorosilane are: the integral molar quantity of dimethyldichlorosilane(DMCS) and diphenyl dichlorosilane is 0.2 mol, and the mass ratio of dimethyldichlorosilane(DMCS) and diphenyl dichlorosilane is 18.07:15.19.

3. the preparation method of methyl phenyl silicone oil according to claim 1, it is characterized in that, wherein the end-capping reagent described in the step (1) is trimethylchlorosilane, add-on is: total mol ratio of trimethylchlorosilane and dimethyldichlorosilane(DMCS) and diphenyl dichlorosilane is 1:10～1:80, is 0.2716～2.1728 g.

4. the preparation method of methyl phenyl silicone oil according to claim 1, it is characterized in that, when wherein the adding condensation catalyst carries out condensation reaction in the step (2), the condensation catalyst add-on is 0.01% ~ 0.2% of dimethyldichlorosilane(DMCS) and diphenyl dichlorosilane total mass, is 0.0133 g～0.2660 g.

5. the preparation method of methyl phenyl silicone oil according to claim 1 is characterized in that, wherein the condensation catalyst described in the step (2) is the ethanolic soln of 25wt% sodium ethylate.

6. the preparation method of methyl phenyl silicone oil according to claim 1 is characterized in that, the temperature of reaction of the described catalyzer condensation reaction of step (2) is 100 ℃, and condensation reaction time is 3h.

Images