CN107384303A - Silicone sealant that steam-preventing passes through and preparation method thereof - Google Patents

Abstract

The present invention proposes the silicone sealant that a kind of steam-preventing passes through, according to the number of parts by weight, including following raw material：α, 0.2~1 part of 80~90 parts of ω dialkyl polydimethylsiloxanes, 10~20 parts of Petropols, 30~50 parts of dimethicone, 20~40 parts of fire retardant, 20~40 parts of reinforced filling, 2~6 parts of aerosil, 2~5 parts of crosslinking agent, 2~5 parts of coupling agent and catalyst, the reinforced filling is made up of nano-cellulose whisker, ZnOw and CNT, and the fire retardant is made up of TDE and aluminium hydroxide.The fluid sealant has good fire-retardant and mechanical performance, while can prevent water vapour from passing through.

Description

Water vapor permeable silicone sealant and preparation method thereof

technical field

The invention belongs to the technical field of sealing materials, and in particular relates to a waterproof vapor permeable silicone sealant and a preparation method thereof.

Background technique

Silicone sealant has excellent resistance to weather, heat and humidity, ultraviolet rays and ozone aging performance, and is one of the preferred materials for building sealants. With the wide application of building curtain walls, silicone sealant has been developed rapidly. Dry-hanging stone curtain walls are rising rapidly, and stone has become one of the mainstream decorations for exterior walls of high-end buildings. Therefore, the application of silicone stone sealants is increasing year by year.

Chinese Invention Patent Application Publication No. CN1865383A discloses an electronic flame retardant silicone sealant and its manufacturing method, which explains the advantages of using magnesium hydroxide and aluminum hydroxide instead of halogen flame retardants, but the patent application scheme does not involve The problem of water vapor penetration. The applicant has also retrieved other relevant patent documents, for example, in the flame-retardant silicone structural sealant disclosed in CN1687288A and its manufacturing method and the intumescent flame-retardant silicone sealant and its manufacturing method provided by CN101368080A, none of them have improved the silicon The waterproof vapor transmission performance of ketone sealant gives technical inspiration.

Contents of the invention

The present invention proposes a silicone sealant that is waterproof and vapor permeable. The sealant has good flame retardancy and mechanical properties, and can prevent water vapor permeation at the same time.

Technical scheme of the present invention is realized like this:

A silicone sealant for water vapor penetration, calculated in parts by weight, comprising the following raw materials:

80-90 parts of α, ω-dihydroxy polydimethylsiloxane, 10-20 parts of petroleum resin, 30-50 parts of dimethyl silicone oil, 20-40 parts of flame retardant, 20-40 parts of reinforcing filler, 2-6 parts of fumed silica, 2-5 parts of cross-linking agent, 2-5 parts of coupling agent and 0.2-1 part of catalyst, the reinforcing filler is composed of nano-cellulose whiskers, zinc oxide whiskers and carbon nano The flame retardant is composed of decabromodiphenylethane and aluminum hydroxide.

Preferably, the mass ratio of the nanocellulose whiskers, zinc oxide whiskers and carbon nanotubes is 5-6:3-4:1-3.

Preferably, the crosslinking agent is one or more selected from methyltriacetoxysilane, vinyltriacetoxysilane and propyltriacetoxysilane.

Preferably, the coupling agent is selected from γ-(2,3 glycidoxy)propyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane or γ-aminopropyltriethylsilane Oxysilane.

Preferably, the catalyst is a mixture of dibutyltin dilaurate, stannous octoate and isopropyl titanate.

Another object of the present invention is to provide a method for preparing a waterproof vapor permeable silicone sealant, comprising the following steps:

1) Add α, ω-dihydroxypolydimethylsiloxane, petroleum resin, catalyst and reinforcing filler into the vacuum kneader, dehydrate and blend at a temperature of 100-160°C and a vacuum of 0.06-0.085MPa for 60 ~300 minutes, cooled to room temperature to obtain mixture A;

2) Add simethicone oil, flame retardant, cross-linking agent, fumed silica and coupling agent into mixture A, stir and mix, and carry out chemical reaction for 60-120 minutes at a vacuum degree of 0.06-0.085 MPa to obtain the product.

Beneficial effects of the present invention:

1. The reinforcing filler used in the present invention is composed of nano-cellulose whiskers, zinc oxide whiskers and carbon nanotubes, which not only promotes the dispersion of reinforcing fillers with more content in the silicone rubber matrix, but also greatly enhances its chemical reaction contact. Surface and activity, improve the tensile strength and elongation at break of the product, ideal weather resistance and corrosion resistance, the tensile strength after immersion in water is 2.15 ~ 2.34MPa. The reinforcing filler also acts synergistically with the petroleum resin to promote the dispersion and wrapping of the resin on the silicone rubber matrix and reduce the water vapor transmission rate of the silicone rubber matrix.

2. The present invention uses a flame retardant composed of decabromodiphenylethane and aluminum hydroxide, and its combustion performance reaches FV-0 level.

detailed description

Example 1

A silicone sealant for water vapor penetration, calculated in parts by weight, comprising the following raw materials:

86 parts of α, ω-dihydroxy polydimethylsiloxane, 15 parts of petroleum resin, 40 parts of dimethyl silicone oil, 31 parts of flame retardant, 28 parts of reinforcing filler, 4 parts of fumed silica, 3.5 parts of acetoxysilane, 3.5 parts of γ-methacryloxypropyltrimethoxysilane, and 0.6 parts of catalyst.

The reinforcing filler is composed of nanocellulose whiskers, zinc oxide whiskers and carbon nanotubes, and the mass ratio of nanocellulose whiskers, zinc oxide whiskers and carbon nanotubes is 5:3:3. The flame retardant consists of decabromodiphenylethane and aluminum hydroxide. The catalyst is a mixture of dibutyltin dilaurate, stannous octoate and isopropyl titanate.

Preparation:

1) Add α, ω-dihydroxy polydimethylsiloxane, petroleum resin, catalyst and reinforcing filler into a vacuum kneader, dehydrate and blend for 100 minutes at a temperature of 120°C and a vacuum of 0.075MPa, and cool down to Mixture A is obtained at room temperature;

2) Add simethicone oil, flame retardant, methyltriacetoxysilane, fumed silica and γ-methacryloxypropyltrimethoxysilane to mixture A and stir to mix, the vacuum degree is 0.06 MPa, carry out chemical reaction for 120 minutes, that is.

Example 2

A silicone sealant for water vapor penetration, calculated in parts by weight, comprising the following raw materials:

80 parts of α, ω-dihydroxy polydimethylsiloxane, 20 parts of petroleum resin, 30 parts of dimethyl silicone oil, 20 parts of flame retardant, 20 parts of reinforcing filler, 6 parts of fumed silica, vinyl tri 2 parts of acetoxysilane, 2 parts of γ-(2,3 glycidoxy)propyltrimethoxysilane and 0.2 parts of catalyst.

The reinforcing filler is composed of nanocellulose whiskers, zinc oxide whiskers and carbon nanotubes, and the mass ratio of nanocellulose whiskers, zinc oxide whiskers and carbon nanotubes is 6:3:2. The flame retardant consists of decabromodiphenylethane and aluminum hydroxide. The catalyst is a mixture of dibutyltin dilaurate, stannous octoate and isopropyl titanate.

Preparation:

1) Add α, ω-dihydroxy polydimethylsiloxane, petroleum resin, catalyst and reinforcing filler into the vacuum kneader, dehydrate and blend for 300 minutes at a temperature of 160°C and a vacuum of 0.06MPa, and cool down to Mixture A is obtained at room temperature;

2) Add simethicone oil, flame retardant, vinyltriacetoxysilane, fumed silica and γ-(2,3 glycidoxy)propyltrimethoxysilane to mixture A and stir to mix. The density is 0.06MPa, and the chemical reaction is carried out for 120 minutes.

Example 3

A silicone sealant for water vapor penetration, calculated in parts by weight, comprising the following raw materials:

90 parts of α, ω-dihydroxy polydimethylsiloxane, 10 parts of petroleum resin, 50 parts of dimethyl silicone oil, 40 parts of flame retardant, 40 parts of reinforcing filler, 2 parts of fumed silica, propyl trimethicone 5 parts of acetoxysilane, 5 parts of γ-aminopropyltriethoxysilane and 1 part of catalyst.

The reinforcing filler is composed of nano-cellulose whiskers, zinc oxide whiskers and carbon nanotubes, and the mass ratio of nano-cellulose whiskers, zinc oxide whiskers and carbon nanotubes is 5:4:3. The flame retardant consists of decabromodiphenylethane and aluminum hydroxide. The catalyst is a mixture of dibutyltin dilaurate, stannous octoate and isopropyl titanate.

Preparation:

1) Add α, ω-dihydroxy polydimethylsiloxane, petroleum resin, catalyst and reinforcing filler into the vacuum kneader, dehydrate and blend for 60-300 minutes at a temperature of 100°C and a vacuum of 0.085MPa, Cool to room temperature to obtain mixture A;

2) Add simethicone oil, flame retardant, propyltriacetoxysilane, fumed silica and γ-aminopropyltriethoxysilane to mixture A and stir to mix, the vacuum degree is 0.06-0.085MPa, The chemical reaction is carried out for 60-120 minutes, and the product is obtained.

Example 4

A silicone sealant for water vapor penetration, calculated in parts by weight, comprising the following raw materials:

82 parts of α, ω-dihydroxy polydimethylsiloxane, 15 parts of petroleum resin, 30 parts of dimethyl silicone oil, 20 parts of flame retardant, 20 parts of reinforcing filler, 6 parts of fumed silica, vinyl tri 2 parts of acetoxysilane, 2 parts of γ-(2,3 glycidoxy)propyltrimethoxysilane and 0.2 parts of catalyst.

The reinforcing filler is composed of nano-cellulose whiskers, zinc oxide whiskers and carbon nanotubes, and the mass ratio of nano-cellulose whiskers, zinc oxide whiskers and carbon nanotubes is 5:4:3. The flame retardant consists of decabromodiphenylethane and aluminum hydroxide. The catalyst is a mixture of dibutyltin dilaurate, stannous octoate and isopropyl titanate.

Preparation:

1) Add α, ω-dihydroxy polydimethylsiloxane, petroleum resin, catalyst and reinforcing filler into the vacuum kneader, dehydrate and blend for 200 minutes at a temperature of 150°C and a vacuum of 0.07MPa, and cool down to Mixture A is obtained at room temperature;

2) Add simethicone oil, flame retardant, vinyltriacetoxysilane, fumed silica and γ-(2,3 glycidoxy)propyltrimethoxysilane to mixture A and stir to mix. The density is 0.075MPa, and the chemical reaction is carried out for 80 minutes.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included in the scope of the present invention. within the scope of protection.

Claims (6)

1. A silicone sealant for water vapor penetration, characterized in that, calculated in parts by weight, comprising the following raw materials: 80-90 parts of α, ω-dihydroxy polydimethylsiloxane, 10-20 parts of petroleum resin, 30-50 parts of dimethyl silicone oil, 20-40 parts of flame retardant, 20-40 parts of reinforcing filler, 2-6 parts of fumed silica, 2-5 parts of cross-linking agent, 2-5 parts of coupling agent and 0.2-1 part of catalyst, the reinforcing filler is composed of nano-cellulose whiskers, zinc oxide whiskers and carbon nano The flame retardant is composed of decabromodiphenylethane and aluminum hydroxide. 2. The silicone sealant for waterproof vapor permeation according to claim 1, characterized in that, the mass ratio of the nanocellulose whiskers, zinc oxide whiskers and carbon nanotubes is 5～6:3～ 4:1～3. 3. The waterproof vapor permeable silicone sealant according to claim 1, wherein the crosslinking agent is selected from the group consisting of methyltriacetoxysilane, vinyltriacetoxysilane and propyltriacetylsilane One or two or more of oxysilanes. 4. The silicone sealant according to claim 1, wherein said coupling agent is selected from γ-(2,3 glycidoxy) propyltrimethoxysilane, γ- Methacryloxypropyltrimethoxysilane or γ-aminopropyltriethoxysilane. 5 . The waterproof vapor permeable silicone sealant according to claim 1 , wherein the catalyst is a mixture of dibutyltin dilaurate, stannous octoate and isopropyl titanate. 6. the preparation method of the silicone sealant of waterproof vapor permeation as claimed in claim 1, is characterized in that, comprises the following steps: 1) Add α, ω-dihydroxypolydimethylsiloxane, petroleum resin, catalyst and reinforcing filler into the vacuum kneader, dehydrate and blend at a temperature of 100-160°C and a vacuum of 0.06-0.085MPa for 60 ~300 minutes, cooled to room temperature to obtain mixture A; 2) Add simethicone oil, flame retardant, cross-linking agent, fumed silica and coupling agent into mixture A, stir and mix, and carry out chemical reaction for 60-120 minutes at a vacuum degree of 0.06-0.085 MPa to obtain the product.