A kind of preparation method of dimethylvinylsiloxy-terminated low-hydroxyl content mdt silicone oil

Abstract

The invention relates to the field of organic synthesis, in order to solve the poor storage stability of the silicone oil caused by the high content of silanol in the MDT silicone oil molecule of the branched chain structure and the release of gas from the reaction with the platinum catalyst when used as a release agent component, resulting in the presence of bubbles in the release agent. To solve the problem of curing rate and quality of the release agent, the present invention proposes a method for preparing dimethylvinylsiloxy-terminated MDT silicone oil with low hydroxyl content by reactive distillation. The prepared dimethylvinylsiloxy-terminated The high-end MDT silicone oil has low residual silanol content, uniform molecular weight distribution of silicone oil, simple preparation process, and is convenient for large-scale production.

Description

technical field

[0001] The invention relates to the field of organic synthesis, in particular to a method for preparing dimethylvinylsiloxy-terminated MDT silicone oil with low hydroxyl content by adopting a reactive distillation coupling method. Background technique

[0002] MDT silicone oil is a kind of branched chain silicone oil, which is a kind of liquid polyorganosiloxane containing polyorganosiloxane branches formed by introducing trifunctional chains into the linear silicone oil molecular chain as branch points. The existence of branched chain structure in the molecule leads to the degree of entanglement of branched silicone oil molecular chains greater than that of linear polydimethylsiloxane. Under the action of shear force, the viscosity of branched chain silicone oil decreases, that is, there is a shear thinning effect, which belongs to non-Newtonian fluid. At present, branched chain silicone oil has been widely used in cosmetics, paper anti-adhesive release age...

Examples

Embodiment 1

[0038] (1) Add 727.20g (3.90mol) of 1,3-divinyl-1,1,3,3-tetramethyldisilazium to a 3000mL three-necked flask equipped with a stirring device, a thermometer and a reflux condenser at room temperature Oxygen, the temperature was raised to 35°C under stirring, and then the mixed solution consisting of 702.00g (39.0mol) of deionized water and 62.88g (0.637mol) of concentrated HCl with a concentration of 37% was mixed for 2h through a constant pressure dropping funnel. Add it dropwise to the reaction vessel at a constant speed. After the dropwise addition, raise the temperature of the reactant to 70° C. and react at this temperature for 3 hours. After the reaction was finished, it was cooled to room temperature, and the reaction product was two layers up and down;

[0039] (2) Add 531.60g (3.90mol) of methyltrimethoxysilane and 314.40g of toluene into another 5000mL three-necked flask equipped with a stirring device, a thermometer and a reflux condenser, and keep the system tempera...

Embodiment 2

[0043] (1) Add 727.20 g (3.90 mol) of 1,3-divinyl-1,1,3,3-tetramethyldisilazium to a 3000 mL three-necked flask equipped with a stirring device, a thermometer and a reflux condenser at room temperature Oxygen, under stirring, be warmed up to 45 ℃, then through the constant pressure dropping funnel, the mixed solution that the premixed 702.00g (39.0mol) deionized water and 62.88g (0.637mol) concentration is the concentrated HCl composition of 37% is passed through 2.5 h was added dropwise to the reaction vessel at a constant speed. After the dropwise addition, the temperature of the reactant was raised to 70° C. and reacted at this temperature for 3 h. After the reaction was finished, it was cooled to room temperature, and the reaction product was two layers up and down;

[0044] (2) Add 531.60g (3.90mol) of methyltrimethoxysilane and 314.40g of toluene to another 5000mL three-necked flask equipped with a stirring device, a thermometer and a reflux condenser, and keep the syste...

Embodiment 3

[0048] (1) Add 181.80 g (0.975 mol) of 1,3-divinyl-1,1,3,3-tetramethyldisilazium to a 1000 mL three-necked flask equipped with a stirring device, a thermometer and a reflux condenser at room temperature Oxygen, the temperature was raised to 30°C under stirring, and then the mixed solution composed of 175.50g (9.75mol) deionized water and 15.72g (0.159mol) concentration of 37% concentrated HCl was passed through a constant pressure dropping funnel through 0.75 h was added dropwise to the reaction vessel at a constant speed. After the dropwise addition, the temperature of the reactant was raised to 65° C. and reacted at this temperature for 4 hours. After the reaction was finished, it was cooled to room temperature, and the reaction product was two layers up and down;

[0049] (2) Add 132.90g (0.976mol) of methyltrimethoxysilane and 78.60g of toluene to another 1000mL three-necked flask equipped with a stirring device, a thermometer and a reflux condenser, and keep the system te...

technical field

[0001] The invention relates to the field of organic synthesis, in particular to a method for preparing dimethylvinylsiloxy-terminated MDT silicone oil with low hydroxyl content by adopting a reactive distillation coupling method. Background technique

[0002] MDT silicone oil is a kind of branched chain silicone oil, which is a kind of liquid polyorganosiloxane containing polyorganosiloxane branches formed by introducing trifunctional chains into the linear silicone oil molecular chain as branch points. The existence of branched chain structure in the molecule leads to the degree of entanglement of branched silicone oil molecular chains greater than that of linear polydimethylsiloxane. Under the action of shear force, the viscosity of branched chain silicone oil decreases, that is, there is a shear thinning effect, which belongs to non-Newtonian fluid. At present, branched chain silicone oil has been widely used in cosmetics, paper anti-adhesive release age...

Examples

Embodiment 1

[0038] (1) Add 727.20g (3.90mol) of 1,3-divinyl-1,1,3,3-tetramethyldisilazium to a 3000mL three-necked flask equipped with a stirring device, a thermometer and a reflux condenser at room temperature Oxygen, the temperature was raised to 35°C under stirring, and then the mixed solution consisting of 702.00g (39.0mol) of deionized water and 62.88g (0.637mol) of concentrated HCl with a concentration of 37% was mixed for 2h through a constant pressure dropping funnel. Add it dropwise to the reaction vessel at a constant speed. After the dropwise addition, raise the temperature of the reactant to 70° C. and react at this temperature for 3 hours. After the reaction was finished, it was cooled to room temperature, and the reaction product was two layers up and down;

[0039] (2) Add 531.60g (3.90mol) of methyltrimethoxysilane and 314.40g of toluene into another 5000mL three-necked flask equipped with a stirring device, a thermometer and a reflux condenser, and keep the system tempera...

Embodiment 2

[0043] (1) Add 727.20 g (3.90 mol) of 1,3-divinyl-1,1,3,3-tetramethyldisilazium to a 3000 mL three-necked flask equipped with a stirring device, a thermometer and a reflux condenser at room temperature Oxygen, under stirring, be warmed up to 45 ℃, then through the constant pressure dropping funnel, the mixed solution that the premixed 702.00g (39.0mol) deionized water and 62.88g (0.637mol) concentration is the concentrated HCl composition of 37% is passed through 2.5 h was added dropwise to the reaction vessel at a constant speed. After the dropwise addition, the temperature of the reactant was raised to 70° C. and reacted at this temperature for 3 h. After the reaction was finished, it was cooled to room temperature, and the reaction product was two layers up and down;

[0044] (2) Add 531.60g (3.90mol) of methyltrimethoxysilane and 314.40g of toluene to another 5000mL three-necked flask equipped with a stirring device, a thermometer and a reflux condenser, and keep the syste...

Embodiment 3

[0048] (1) Add 181.80 g (0.975 mol) of 1,3-divinyl-1,1,3,3-tetramethyldisilazium to a 1000 mL three-necked flask equipped with a stirring device, a thermometer and a reflux condenser at room temperature Oxygen, the temperature was raised to 30°C under stirring, and then the mixed solution composed of 175.50g (9.75mol) deionized water and 15.72g (0.159mol) concentration of 37% concentrated HCl was passed through a constant pressure dropping funnel through 0.75 h was added dropwise to the reaction vessel at a constant speed. After the dropwise addition, the temperature of the reactant was raised to 65° C. and reacted at this temperature for 4 hours. After the reaction was finished, it was cooled to room temperature, and the reaction product was two layers up and down;

[0049] (2) Add 132.90g (0.976mol) of methyltrimethoxysilane and 78.60g of toluene to another 1000mL three-necked flask equipped with a stirring device, a thermometer and a reflux condenser, and keep the system te...

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