CN104892944B - A kind of preparation method of (methyl) acryloyloxymethyl terminated polysiloxane - Google Patents

Abstract

The invention relates to a preparation method of (meth)acryloyloxymethyl-terminated polysiloxane, comprising the following steps: (1) adding (meth)acryloyloxymethyl (meth)acryloyloxy Mix base silane and hydroxy polysiloxane, add or not add organic solvent, mix uniformly to obtain mixed material; (2) Stir the mixed material obtained in step (1) under the protection of inert gas at 15-60°C for 5- 15 hours; (3) After the reaction is completed, cool to room temperature naturally, remove the organic solvent, extract with methanol, dry the extract, remove methanol, and obtain the product. The method of the invention has easy-to-obtain raw materials, no need for harsh reaction conditions, simple operation, high-efficiency reaction, and simple post-treatment; avoiding the use of expensive platinum catalysts as raw materials, and the reaction can effectively control the polymerization of double bonds, and the conversion rate of the reaction hydroxyl group is high and the yield is high. High rate and few side effects.

Description

A kind of preparation method of (meth)acryloxymethyl-terminated polysiloxane

technical field

The invention relates to a preparation method of (meth)acryloyloxymethyl-terminated polysiloxane, which belongs to the technical field of organosilicon polymer synthesis.

Background technique

(Meth)acryloyloxyalkyl-terminated polysiloxane is a kind of organosilicon compound with high reactivity, which can be widely used as active organosilicon polymer in the field of organosilicon polymer synthesis. The double bond and acyloxy endow this type of polysiloxane with new reactivity, so that this type of polysiloxane can be widely used as a crosslinking agent in the fields of silicone resin, silicone rubber, and silicone coatings.

In the prior art, the preparation method of (meth)acryloyloxyalkyl-terminated polysiloxane is mainly the hydrosilylation method. The polysiloxane terminated by silicon hydrogen and diolefin carboxylate are added under the condition of platinum compound catalyst. The catalyst is expensive and the reaction conditions are strict. The catalyst is easy to deactivate and the operation is complicated. Moreover, the silicon atom and the acyloxy group in the (meth)acryloyloxyalkyl-terminated polysiloxane produced by this method have more than two carbon atoms connected, and the acyloxy group cannot be obtained through only one methylene group and the polysiloxane. (Meth)acryloyloxymethyl-terminated polysiloxane with silicon atoms attached to the siloxane.

The characteristics of the prior art determine that the cost of raw materials for the preparation of (meth)acryloyloxyalkyl-terminated polysiloxane is relatively high, and the preparation method is harsh, so the obtained (meth)acryloyloxyalkyl-terminated polysiloxane The high cost of siloxanes hinders the use of these compounds. At present, there is no preparation method of (meth)acryloyloxymethyl-terminated polysiloxane with simple operation, high reaction efficiency, rapidity and low cost.

Contents of the invention

Aiming at the deficiencies of the prior art, the present invention provides a simple, safe, economical, high yield, high purity and less side reaction preparation method for (meth)acryloyloxymethyl-terminated polysiloxane.

Technical scheme of the present invention is as follows:

A preparation method of (meth)acryloyloxymethyl-terminated polysiloxane, the structural formula of the (meth)acryloyloxymethyl-terminated polysiloxane is shown in formula (I) ,

Including the following steps:

(1) Mix (meth)acryloyloxymethyl(meth)acryloyloxysilane and hydroxypolysiloxane, add or not add an organic solvent, and mix evenly to obtain a mixed material;

The structural formula of the (meth)acryloxymethyl (meth)acryloxysilane is shown in formula (II),

The structural formula of the hydroxypolysiloxane is shown in formula (III),

In formula (I), (II), (III), R ₁ is hydrogen atom or methyl group, R ₂ and R ₃ are methyl group or ethyl group, R ₄ and R ₅ are hydrogen atom, methyl group, ethyl group or Vinyl, n=10～8105, m=n+2;

(2) Stirring and reacting the mixed material obtained in step (1) at 15-60°C for 5-15 hours under the protection of an inert gas;

(3) After the reaction is completed, cool naturally to room temperature, remove the organic solvent, extract with methanol, dry the extract, remove methanol, and obtain the product.

According to the present invention, preferably, the molar ratio of the (meth)acryloyloxymethyl (meth)acryloyloxysilane described in step (1) to the hydroxyl group in the hydroxyl polysiloxane is (1-1.5 ):1;

Preferably, the molecular weight of the hydroxy polysiloxane is 1000-600000 g/mol.

According to the present invention, preferably, when an organic solvent is added in step (1), the organic solvent is toluene or xylene;

Preferably, the mass ratio of the organic solvent to the hydroxyl polysiloxane is (1-6):1.

According to the present invention, preferably, the reaction temperature in step (2) is 30-60° C., and the reaction time is 8-15 hours.

According to the present invention, the (meth)acryloyloxymethyl(meth)acryloyloxysilane is commercially available or self-made, preferably prepared as follows:

(i) adding acrylic acid or acrylic acid salt or methacrylic acid or methacrylic acid salt, a polymerization inhibitor, and a phase transfer catalyst to an organic solvent, and mixing uniformly to obtain a mixed material;

Described inhibitor is 2,6-di-tert-butyl-4-methylphenol, p-tert-butylcatechol, 4-4-methylene bis(2,6-di-tert-butylphenol) One; the amount of the polymerization inhibitor is 0.1% to 2% of the molar amount of acrylic acid or acrylate or methacrylic acid or methacrylate;

Described phase-transfer catalyst is a kind of in tetraethylammonium bromide, tetrabutylammonium chloride, tetrabutylphosphine bromide; The consumption of phase-transfer catalyst is acrylic acid or acrylate or methacrylic acid or methacrylic acid 0.2-5% of the molar amount of salt;

Described organic solvent is toluene or xylene;

(ii) Adding chloromethylchlorosilane dropwise to the mixture obtained in step (i), under the protection of an inert gas, stirring and reacting at 70-100°C for 8-15 hours;

(iii) After the reaction is completed, cool naturally to room temperature, filter under reduced pressure, remove the organic solvent from the filtrate, and distill under reduced pressure to obtain final product. The obtained product was a colorless transparent liquid.

According to the present invention, preferably, the molar ratio of the acrylic acid or acrylic acid salt or methacrylic acid or methacrylic acid salt described in step (i) to the chloromethylchlorosilane described in step (ii) is (1-3) :1, more preferably (2～2.5):1.

The hydroxypolysiloxane used in the present invention is commercially available, and can also be prepared according to conventional techniques in the art.

According to the present invention, the above reaction can be carried out in a three-neck round bottom flask equipped with a constant pressure dropping funnel, a dryer, a magnet and a T-type three-way stopcock.

Principle of the present invention:

Reaction formula of the present invention is as follows:

Si-O-CO- is an active group, and the carboxylic acid can be removed by reacting with Si-OH under mild conditions without the presence of a catalyst. The reaction is a nucleophilic reaction with simple conditions and a high degree of reaction.

Beneficial effects of the present invention:

The method of the invention has easy-to-obtain raw materials, no harsh reaction conditions, simple operation, high reaction efficiency and simple post-treatment. Avoid the use of expensive platinum catalysts as raw materials, and the reaction can effectively control the polymerization of double bonds. The conversion rate of hydroxyl groups is high, the yield is high, and side reactions are few. High temperature and high pressure reactions are avoided. Laboratory preparation and industrial production of methyl-terminated polysiloxane.

Description of drawings

Fig. 1 is an infrared spectrogram of the reactant hydroxy polydimethylsiloxane in Example 1 of the present invention.

Fig. 2 is the H NMR spectrum of the reactant hydroxy polydimethylsiloxane in Example 1 of the present invention.

Fig. 3 is the infrared spectrogram of the product obtained in Example 1 of the present invention.

Fig. 4 is the proton NMR spectrogram of the product obtained in Example 1 of the present invention.

Detailed ways

The present invention will be further described below in conjunction with embodiment, and following embodiment is illustrative, not limiting, can not limit protection scope of the present invention with following embodiment.

The raw material (meth)acryloyloxymethyl (meth)acryloyloxysilane used in the examples was prepared as follows:

(i) adding sodium acrylate or sodium methacrylate, a polymerization inhibitor, and a phase transfer catalyst into an organic solvent, and mixing uniformly to obtain a mixed material;

The polymerization inhibitor is p-tert-butylcatechol; the consumption of the polymerization inhibitor is 1% of the molar consumption of sodium acrylate or sodium methacrylate;

The phase transfer catalyst is tetrabutylammonium chloride; the amount of the phase transfer catalyst is 3% of the molar amount of sodium acrylate or sodium methacrylate;

Described organic solvent is toluene;

(ii) Adding chloromethylchlorosilane dropwise to the mixed material obtained in step (i), under the protection of an inert gas, stirred and reacted at 90° C. for 10 hours; the chloromethylchlorosilane used in the examples is a commercially available product;

(iii) After the reaction is completed, cool naturally to room temperature, filter under reduced pressure, remove the organic solvent from the filtrate, and distill under reduced pressure to obtain final product.

The hydroxypolysiloxane used in the examples is a commercially available product.

Embodiment 1, the preparation of acryloyloxymethyl-terminated polydimethylsiloxane

The structural formula of acryloyloxymethyl-terminated polydimethylsiloxane is shown in formula (IV),

Including the following steps:

In a three-neck round bottom flask equipped with a constant pressure dropping funnel, a desiccator, a magnet and a T-shaped three-way stopcock, put 20.03 g of hydroxypolydimethylsiloxane with a molecular weight of 5000 g/mol, and 1.78 g of propylene Acyloxymethacryloyloxydimethylsilane was slowly added dropwise to the reaction flask and stirred slowly. After the dropwise addition was completed, it was incubated at 20°C for 5 hours. After the reaction was completed, it was extracted with methanol, and the extract was dried and removed. Methanol yields the product, acryloxymethyl-terminated polydimethylsiloxane. Yield 84.29%.

The infrared and hydrogen NMR spectra of the reactant hydroxy polydimethylsiloxane and the obtained product in this example are shown in Figure 1, Figure 2, Figure 3, and Figure 4.

Embodiment 2, the preparation of methacryloyloxymethyl-terminated polymethylhydrogensiloxane

The structural formula of methacryloyloxymethyl-terminated polymethylhydrogensiloxane is shown in formula (Ⅴ),

Including the following steps:

In a three-neck round bottom flask equipped with a constant pressure dropping funnel, a desiccator, a magnet and a T-shaped three-way piston, put 9.82g of hydroxypolymethylhydrogensiloxane with a molecular weight of 10000g/mol, and 0.43g of formazan Acryloyloxymethylmethacryloyloxydimethylsilane was slowly added dropwise to the reaction flask and stirred slowly. After the dropwise addition was completed, the reaction was kept at 30°C for 6 hours. After the reaction was completed, it was naturally cooled to room temperature. Extract with methanol, dry the extract, and remove the methanol to obtain the product, that is, methacryloyloxymethyl-terminated polymethylhydrogensiloxane. Yield 83.16%.

Embodiment 3, preparation of acryloyloxymethyl-terminated polymethylvinylsiloxane

The structural formula of acryloxymethyl-terminated polymethylvinylsiloxane is shown in formula (Ⅵ),

Including the following steps:

In a three-necked round-bottomed flask equipped with a constant pressure dropping funnel, a desiccator, a magnet and a T-shaped three-way piston, put 50.02 g of hydroxypolymethylvinyl siloxane with a molecular weight of 200,000 g/mol, and 100.05 g of toluene , after stirring and dissolving, dissolve 0.12g of acryloyloxymethacryloyloxydimethylsilane in an organic solvent and slowly add it dropwise to the reaction flask. Naturally cool to room temperature, remove the organic solvent, extract with methanol, dry the extract, remove methanol to obtain the product, that is, acryloyloxymethyl-terminated polymethylvinylsiloxane. Yield 89.25%.

Embodiment 4, preparation of acryloyloxymethyl-terminated polydimethylsiloxane

The structural formula of acryloyloxymethyl-terminated polydimethylsiloxane is shown in formula (VII),

Including the following steps:

In a three-necked round-bottom flask equipped with a constant pressure dropping funnel, a desiccator, a magnet and a T-shaped three-way piston, put 100.06 g of hydroxypolydimethylsiloxane with a molecular weight of 600,000 g/mol, and 400.18 g of xylene , after stirring and dissolving, dissolve 0.09g of acryloyloxymethacryloyloxydimethylsilane in an organic solvent and slowly add it dropwise to the reaction flask. Naturally cool to room temperature, remove the organic solvent, extract with methanol, dry the extract, remove methanol to obtain the product, that is, acryloyloxymethyl-terminated polydimethylsiloxane. Yield 92.47%.

Claims (8)

1. A preparation method of (meth)acryloyloxymethyl-terminated polysiloxane, the structural formula of the (meth)acryloyloxymethyl-terminated polysiloxane is as formula (I) as shown, (I), Including the following steps: (1) Mix (meth)acryloyloxymethyl(meth)acryloyloxysilane and hydroxypolysiloxane, add or not add organic solvent, and mix well to obtain a mixed material; The molar ratio of the hydroxyl groups in the (meth)acryloxymethyl (meth)acryloxysilane to the hydroxyl polysiloxane is (1~1.5):1; The structural formula of the (meth)acryloyloxymethyl(meth)acryloyloxysilane is shown in formula (II), (II), The structural formula of the hydroxypolysiloxane is shown in formula (III), (III), In formula (I), (II), (III), R ₁ is hydrogen atom or methyl group, R ₂ and R ₃ are methyl group or ethyl group, R ₄ and R ₅ are hydrogen atom, methyl group, ethyl group or Vinyl, n=10~8105, m=n+2; (2) Stir the mixed material obtained in step (1) at 30-60°C for 8-15 hours under the protection of an inert gas; (3) After the reaction is completed, cool naturally to room temperature, remove the organic solvent, extract with methanol, dry the extract, and remove methanol to obtain the product. 2. The preparation method according to claim 1, characterized in that the molecular weight of the hydroxy polysiloxane in step (1) is 1000-600000 g/mol. 3. The preparation method according to claim 1, characterized in that, when an organic solvent is added in step (1), the organic solvent is toluene or xylene. 4. The preparation method according to claim 1, characterized in that, when the organic solvent is added in step (1), the mass ratio of the organic solvent to the hydroxyl polysiloxane is (1-6):1. 5. The preparation method according to claim 1, characterized in that the (meth)acryloyloxymethyl(meth)acryloyloxysilane described in step (1) is prepared as follows: (i) Add acrylic acid or acrylate or methacrylic acid or methacrylate, a polymerization inhibitor, and a phase transfer catalyst into an organic solvent, and mix well to obtain a mixed material; The polymerization inhibitor is 2,6-di-tert-butyl-4-methylphenol, p-tert-butylcatechol, 4-4-methylenebis(2,6-di-tert-butylphenol) A sort of; Described phase-transfer catalyst is the one in tetraethylammonium bromide, tetrabutylammonium chloride, tetrabutylphosphine bromide; Described organic solvent is toluene or xylene; (ii) Adding chloromethylchlorosilane dropwise to the mixed material obtained in step (i), under the protection of an inert gas, stirring and reacting at 70-100°C for 8-15 hours; (iii) After the reaction is completed, cool naturally to room temperature, filter under reduced pressure, remove the organic solvent from the filtrate, and distill under reduced pressure to obtain the product. 6. The preparation method according to claim 5, wherein the amount of the polymerization inhibitor described in step (i) is 0.1-2% of the molar amount of acrylic acid or acrylate or methacrylic acid or methacrylate . 7. The preparation method according to claim 5, wherein the amount of the phase transfer catalyst described in step (i) is 0.2-5% of the molar amount of acrylic acid or acrylate or methacrylic acid or methacrylate . 8. The preparation method according to claim 5, wherein the acrylic acid or acrylic acid salt or methacrylic acid or methacrylic acid salt described in step (i) and the chloromethyl chlorosilane described in step (ii) The molar ratio is (1~3):1.