Modified silica sol, and preparation method and application thereof

Abstract

The invention discloses modified silica sol, and a preparation method and application thereof. The preparation method for the modified silica sol comprises the following steps: preparing olefinic-bond-grafted silica sol; preparing sulfonic-group-grafted silica sol; and subjecting the olefinic-bond-grafted silica sol and the sulfonic-group-grafted silica sol to mixing, stirring and aging so as to obtain silica sol simultaneously grafted with an olefinic bond and a sulfonic group, wherein a mass ratio of the olefinic-bond-grafted silica sol to the sulfonic-group-grafted silica sol is 0.2-1: 1. The modified silica sol prepared by using the method in the invention has excellent hydrophilic property and good compatibility with an organic polymer monomer, and can be used as an important raw material of a super hydrophilic and antifogging coating.

Description

technical field

[0001] The invention relates to the modification technology of functional materials, in particular to a modified silica sol and its preparation method and application. Background technique

[0002] Silica sol is a dispersion of nano-scale silica particles in water or other solvents. Among them, the surface of silica particles contains a large number of hydroxyl groups, so it has a large specific surface area, high dispersibility, adsorption and fire resistance and heat insulation. It is widely used in machinery manufacturing, petrochemical industry, light textile and electronic industry and other fields.

[0003] Since silica sol contains a large number of hydroxyl groups, it has better hydrophilic properties and can be used as an important raw material for super-hydrophilic anti-fog coatings. However, the compatibility between silica sol and organic polymer monomers is poor. In the process of in-situ preparation of silica-polymer composite materials, silica...

Examples

preparation example Construction

[0035] The invention provides a kind of preparation method of modified silica sol, comprises the following steps:

[0036] S100: preparing silica sol grafted with ethylenic bonds.

[0037] Preferably, as a possible embodiment, the preparation of the silica sol grafted with ethylenic bonds comprises the following steps:

[0038] S110, taking a certain amount of silica sol for activation treatment.

[0039] Since the silica sol is prone to agglomeration when standing still, preferably, before use, the silica sol needs to be activated to disperse the particles in the silica sol uniformly, so as to increase the uniformity of the subsequent reaction. As a possible implementation manner, the silica sol is activated in ultrasonic waves for 10 minutes to 60 minutes. In addition, other ways can also be used for activation, for example, the silica sol can be activated by heating or high-speed stirring.

[0040] It should be noted that the silica sol described in this step refers to u...

Embodiment 1

[0078] 1. Activate the silica sol by ultrasonic waves for 30 minutes, wherein the solid content of the silica sol is 5wt%, and the particle size of the silica particles in the silica sol is 5nm;

[0079] 2. Take the partially activated silica sol in step 1, adjust its pH value to 2.5 with acetic acid and stir under a nitrogen atmosphere, and add γ-(methacryloyloxy)propyltrimethoxysilane dropwise while stirring, The dropping time is 30min, wherein, the mass fraction ratio of the added γ-(methacryloyloxy)propyltrimethoxysilane to the solid content of the silica sol taken is 0.5:1; Stirring under a nitrogen atmosphere for 1 h, and then aging for 12 h at room temperature to obtain a silica sol grafted with ethylenic bonds;

[0080] 3. Take the partially activated silica sol in step 1, adjust its pH value to 3 with acetic acid and stir it under a nitrogen atmosphere, add γ-mercaptopropyltriethoxysilane dropwise while stirring, and the dropping time is 30 minutes , wherein, the mas...

Embodiment 2

[0084] 1. Activate the silica sol by ultrasonic waves for 20 minutes, wherein the solid content of the silica sol is 10wt%, and the particle size of the silica particles in the silica sol is 10nm;

[0085] 2. Take the partially activated silica sol in step 1, adjust its pH value to 3 with hydrochloric acid and stir under an argon atmosphere, and add γ-methacryloxypropyltriethoxysilane dropwise while stirring , the dropping time is 40min, wherein, the mass fraction ratio of the added γ-methacryloxypropyltriethoxysilane to the solid content of the silica sol is 0.8:1; Stirring under argon atmosphere for 3h, then aging at room temperature for 16h, to obtain silica sol grafted with ethylenic bonds;

[0086] 3. Take the partially activated silica sol in step 1, adjust its pH value to 4 with hydrochloric acid and stir it under an argon atmosphere, add γ-mercaptopropyltrimethoxysilane dropwise while stirring, and the dropping time is 40 minutes , wherein, the mass fraction ratio of ...

technical field

[0001] The invention relates to the modification technology of functional materials, in particular to a modified silica sol and its preparation method and application. Background technique

[0002] Silica sol is a dispersion of nano-scale silica particles in water or other solvents. Among them, the surface of silica particles contains a large number of hydroxyl groups, so it has a large specific surface area, high dispersibility, adsorption and fire resistance and heat insulation. It is widely used in machinery manufacturing, petrochemical industry, light textile and electronic industry and other fields.

[0003] Since silica sol contains a large number of hydroxyl groups, it has better hydrophilic properties and can be used as an important raw material for super-hydrophilic anti-fog coatings. However, the compatibility between silica sol and organic polymer monomers is poor. In the process of in-situ preparation of silica-polymer composite materials, silica...

Examples

preparation example Construction

[0035] The invention provides a kind of preparation method of modified silica sol, comprises the following steps:

[0036] S100: preparing silica sol grafted with ethylenic bonds.

[0037] Preferably, as a possible embodiment, the preparation of the silica sol grafted with ethylenic bonds comprises the following steps:

[0038] S110, taking a certain amount of silica sol for activation treatment.

[0039] Since the silica sol is prone to agglomeration when standing still, preferably, before use, the silica sol needs to be activated to disperse the particles in the silica sol uniformly, so as to increase the uniformity of the subsequent reaction. As a possible implementation manner, the silica sol is activated in ultrasonic waves for 10 minutes to 60 minutes. In addition, other ways can also be used for activation, for example, the silica sol can be activated by heating or high-speed stirring.

[0040] It should be noted that the silica sol described in this step refers to u...

Embodiment 1

[0078] 1. Activate the silica sol by ultrasonic waves for 30 minutes, wherein the solid content of the silica sol is 5wt%, and the particle size of the silica particles in the silica sol is 5nm;

[0079] 2. Take the partially activated silica sol in step 1, adjust its pH value to 2.5 with acetic acid and stir under a nitrogen atmosphere, and add γ-(methacryloyloxy)propyltrimethoxysilane dropwise while stirring, The dropping time is 30min, wherein, the mass fraction ratio of the added γ-(methacryloyloxy)propyltrimethoxysilane to the solid content of the silica sol taken is 0.5:1; Stirring under a nitrogen atmosphere for 1 h, and then aging for 12 h at room temperature to obtain a silica sol grafted with ethylenic bonds;

[0080] 3. Take the partially activated silica sol in step 1, adjust its pH value to 3 with acetic acid and stir it under a nitrogen atmosphere, add γ-mercaptopropyltriethoxysilane dropwise while stirring, and the dropping time is 30 minutes , wherein, the mas...

Embodiment 2

[0084] 1. Activate the silica sol by ultrasonic waves for 20 minutes, wherein the solid content of the silica sol is 10wt%, and the particle size of the silica particles in the silica sol is 10nm;

[0085] 2. Take the partially activated silica sol in step 1, adjust its pH value to 3 with hydrochloric acid and stir under an argon atmosphere, and add γ-methacryloxypropyltriethoxysilane dropwise while stirring , the dropping time is 40min, wherein, the mass fraction ratio of the added γ-methacryloxypropyltriethoxysilane to the solid content of the silica sol is 0.8:1; Stirring under argon atmosphere for 3h, then aging at room temperature for 16h, to obtain silica sol grafted with ethylenic bonds;

[0086] 3. Take the partially activated silica sol in step 1, adjust its pH value to 4 with hydrochloric acid and stir it under an argon atmosphere, add γ-mercaptopropyltrimethoxysilane dropwise while stirring, and the dropping time is 40 minutes , wherein, the mass fraction ratio of ...

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