Ketoxime quick-drying neutral silicone door and window sealant and preparation method thereof

Abstract

In order to solve the technical problems, the invention provides the ketoxime quick-drying neutral silicone door and window sealant and the preparation method thereof, and the ketoxime quick-drying neutral silicone door and window sealant comprises the following main components: alpha, omega-dihydroxy polysiloxane, methyl silicone oil, a modified filler, a compound cross-linking agent, N-methylimidazole, silane coupling agents, an organic tin catalyst and the like. The ketoxime type neutral silicone weather-proof sealant disclosed by the invention can be quickly cured, and has the functions of good adhesion, operability, aging resistance, waterproof sealing and the like. The silicone sealant disclosed by the invention has the characteristic of rapid curing, can meet the requirement of rapid turn-over gluing of door and window factories, and greatly shortens the time of waiting for turn-over construction of the door and window factories.

Description

Technical Field

[0001] The invention relates to the field of sealants, and in particular to a ketoxime quick-drying neutral silicone door and window sealant and a preparation method thereof. Background Art

[0002] Silicone sealants have good adhesion, displacement ability, and insulation, and are widely used in the construction, electronics, automobile, lighting and other industries. Among them, single-component silicone sealants are widely used in door and window sealing due to their convenient operation, good adhesion and good sealing effect. However, as door and window manufacturers pursue higher and higher efficiency requirements, especially in the low temperature and low humidity environment in winter, the curing speed of sealants seriously affects the manufacturer's delivery speed. The curing speed of conventional single-component silicone door and window sealants obviously cannot meet the requirements of door and window manufacturers. Therefore, it is of great significance to prepare a neutral silicone door and window sealant with good compatibility and quick drying.

[0003] CN202211337440.7 discloses the use of α, ω-dihydroxy polydimethylsiloxane (107 glue) as a basic prepolymer, using hydrophobic silicon powder, hydrophobic gas phase SiO2 as a reinforcing material, adding acetylene black, high-speed mixing and dispersion in a high-speed disperser, and obtaining a delicate basic mixture, and then exposing the material to the air by adding a composite fast-curing cross-linking agent and a catalyst to enable rapid curing, and then coordinating with a coupling agent with high reaction functionality to keep the material and construction materials in good adhesion, and then adding matting powder, it is possible to achieve the purpose of silicone sealant with quick drying and matte black. Hydrophobic silicon powder, hydrophobic nano calcium carbonate, and hydrophobic gas phase silica are added to its reinforcing filler, the moisture of the base glue is greatly reduced, and the stability of the sealant is improved, but only by the compounding of the cross-linking agent, there is a certain restriction on the improvement of the curing speed of the colloid, especially when the door and window factory is used to seal the doors and windows, the curing speed still cannot meet the requirements of its quick drying.

[0004] CN202010042052.0 discloses that α,ω-dihydroxy polydimethylsiloxane is used as a base polymer, and a compound of curing agent ethylenediamine, hexamethylenediamine or triethylenetetramine and synergist hydroxyethyl methacrylate, isocyanate ethyl acrylate and epoxy resin is added to increase the curing speed of the sealant and achieve rapid curing. However, since isocyanate ethyl acrylate has a double bond at one end and can be free radical polymerized, and has an isocyanate at one end and can react with a functional group with active hydrogen, while rapidly increasing the binding capacity, its stability performance decreases, and the addition of a compound synergist can easily cause the hardness of the colloid to be too large and the displacement capacity is almost lost. Summary of the invention

[0005] In order to solve the problem of slow curing speed of door and window sealants, the present application provides a ketoxime quick-drying neutral silicone door and window sealant and a preparation method thereof.

[0006] In a first aspect, the present application provides a ketoxime quick-drying neutral silicone door and window sealant, which is made of the following components in parts by weight: 35-50 parts of α,ω-dihydroxy polysiloxane; 0-20 parts of dimethyl silicone oil; 40-50 parts of modified filler; Compound silane crosslinking agent 4-6 parts; Curing accelerator 0.01-1 part; 1-2 parts of silane coupling agent; Catalyst 0.005-0.03 parts; The viscosity of the α,ω-dihydroxy polysiloxane is 5000-20000 mPa.s, and the viscosity of the dimethyl silicone oil is 100-1000 mPa.s. α,ω-dihydroxy polysiloxane as a base rubber has a certain viscosity to ensure its adhesion; at the same time, dimethyl silicone oil has a certain fluidity to promote its wettability to the collection, and at the same time, as a plasticizer, it plays a certain viscosity reduction role to improve the rheological properties of the rubber.

[0007] By adopting the above technical scheme, α,ω-dihydroxy polysiloxane reacts with excess crosslinking agent to form crosslinking agent-terminated polysiloxane, the curing speed of which is greatly related to the hydrolysis reaction of the crosslinking agent. The condensation crosslinking agent is a silane compound containing multiple easily hydrolyzed groups, and the general formula is R 4-n S Y n Indicates, where R is an alkyl group, usually a methyl group, and the Y group refers to a hydrolyzable group, and n=3 or 4. Different Y groups form different cross-linking systems, and the corresponding order of reactivity is roughly as follows: R 4-n Si[OC(CH3)=CH2] n >R 4-n Si(NR 1 COR 2 ) n >R 4-n Si[OR 1 ] n >R 4-n Si[ON=C(R 1 R 2 )2] n , , in this application, it is preferred to use R 4-n Si[ON=C(R 1 R 2 )2] n (Deoxime type) crosslinking agent and R 4-n Si[OC(CH3)=CH2] n (Deacetone type) cross-linking agent is used in combination.

[0008] Preferably, the compound silane crosslinking agent is compounded with one or more of tetrakis(methyl isobutyl ketone oxime)silane, vinyl triacetone oxime silane, methyl tris(methyl isobutyl ketone oxime) and methyl tris(isopropyleneoxy)silane; in terms of mass ratio, the compounding ratio is (2-3):(0.5-1), thereby improving the vulcanization speed of the finished product.

[0009] Furthermore, the present application adopts a compound of monoaminosilane coupling agent and polyaminosilane coupling agent, which can reduce the product defect rate in the process of glue making and improve product quality. The reason may be that the diaminosilane coupling agent has high activity and poor stability in the process of glue making. After adding the above-mentioned compound cross-linking agent, it is easy to dry the surface too quickly, resulting in undesirable phenomena such as crusting and particles, which is not conducive to improving product quality. Therefore, after the monoaminosilane coupling agent and polyaminosilane coupling agent are compounded, the reaction activity of the sealant is effectively slowed down, thereby avoiding the sealant from drying too quickly and reducing undesirable phenomena such as crusting and particles.

[0010] Preferably, the silane coupling agent comprises at least one monoaminosilane coupling agent and at least one polyaminosilane coupling agent, and the mass ratio of the monoaminosilane coupling agent to the polyaminosilane coupling agent is 1:(1-1.5); wherein the monoaminosilane coupling agent is one or more of γ-aminopropyltrimethoxysilane or γ-aminopropyltriethoxysilane; wherein the polyaminosilane coupling agent is one or more of N-2-aminoethyl-3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane, and 3-diethylenetriaminopropylmethyldimethoxysilane.

[0011] Furthermore, the filler surface used in the present application is modified and prepared according to the following method: S1-1: Add calcium carbonate and stabilizer to the aqueous solution in sequence, disperse evenly by centrifugation, control the temperature at 50-60°C, and keep warm for 30 minutes to obtain a nano calcium carbonate suspension; the stabilizer is sodium nitrilotriacetate; the amount thereof is 1-2% of the dry mass of calcium carbonate; S1-2: After the modifier is heated and melted in an aqueous solution, an emulsifier is added, and the mixture is stirred for 10 to 30 minutes to obtain a modifier emulsion; the modifier is lauric acid, and the total amount thereof is 2.0 to 3.0% of the dry mass of calcium carbonate; the emulsifier is diglycerol polypropylene glycol ether, and the amount thereof is 7 to 20% of the total amount of the modifier; S1-3: Add the nano calcium carbonate suspension obtained in S1-1 to the modifier emulsion, stir thoroughly for 30 to 60 minutes, and then filter press to dehydrate, dry, and grind to obtain the modified filler.

[0012] Preferably, the composite cross-linking agent is a mixture of one or more of tetrakis(methyl isobutyl ketone oxime)silane, vinyl triacetone oxime silane, methyl tris(methyl isobutyl ketone oxime) and methyl tris(isopropyleneoxy)silane, and the composite ratio is 2-3:0-1 in mass proportion; Preferably, the curing accelerator is N-methylimidazole, which is used to ensure that the rubber material is fine and not easy to form a skin during the rubber making process, while ensuring that the finished rubber has a fast deep curing speed.

[0013] Preferably, the catalyst is an organic tin catalyst. The present application has no special restrictions on the organic tin catalyst. Dibutyltin dilaurate, stannous octoate, dibutyltin diacetate, and chelated tin can effectively increase the curing speed of silicone sealant.

[0014] In a second aspect, the present application provides a method for preparing a ketoxime quick-drying neutral silicone door and window sealant, comprising the following steps: S2-1: adding the weight portions of α,ω-dihydroxypolysiloxane, dimethyl silicone oil and modified filler into a kneader, heating to 110-130° C., dehydrating and blending under vacuum, and cooling to room temperature to obtain a semi-finished product; S2-2: Add the above semi-finished product into a planetary mixer, and then add pigment, compound silane crosslinking agent, curing accelerator, silane coupling agent and catalyst in sequence, and obtain the finished product after sufficient reaction under vacuum environment.

[0015] In summary, this application has the following beneficial effects: The present application uses a compound of a deoxime cross-linking agent and a deacetone cross-linking agent, and through a suitable matching process, not only can the chemical resistance of the sealant be improved, so that it can maintain stable performance in various environments; it also overcomes the disadvantage of the slow vulcanization speed of the ketoxime sealant and increases the vulcanization speed of the colloid; it is suitable for the requirements of turning over and re-constructing on the day of construction in the door and window factory, which greatly improves the operability of the workers and the construction efficiency of the door and window factory.

[0016] The present application improves the mechanical properties of the colloid by preparing the base material with modified fillers, and simultaneously adds N-methylimidazole, a coupling agent and a catalyst together, thereby ensuring that the rubber is fine and not prone to skinning during the rubber making process, while also ensuring that the finished rubber has a fast deep curing speed.

[0017] In the present application, a ketoxime quick-drying neutral silicone door and window sealant is prepared by synergistically combining a monoaminosilane coupling agent and a polyaminosilane coupling agent, and at the same time, the problem of a reduced defect rate in the production process of silicone sealants is overcome. DETAILED DESCRIPTION

[0018] The following examples illustrate the present invention, but the present invention is not limited to these examples. Modifications to the specific embodiments of the present invention or equivalent replacement of some technical features without departing from the spirit of the present invention should be included in the scope of the technical solution claimed by the present invention.

[0019] Example 1 A ketoxime quick-drying neutral silicone door and window sealant, comprising the following raw materials and weight proportions: 35 parts of 5000cp α,ω-dihydroxypolysiloxane, 10 parts of 1000cp dimethyl silicone oil, 40 parts of modified filler, 3.2 parts of methyltri(methyl isobutyl ketone oxime), 0.8 parts of methyltri(isopropenyloxy)silane, 0.01 parts of N-methylimidazole, 1 part of γ-aminopropyltriethoxysilane and N-2-aminoethyl-3-aminopropyltrimethoxysilane in a mass ratio of 1:1, and 0.01 parts of dibutyltin dilaurate.

[0020] Preparation of a ketoxime quick-drying neutral silicone door and window sealant, comprising the following steps: S2-1: adding the weight portions of α,ω-dihydroxypolysiloxane, dimethyl silicone oil and modified filler into a kneader, heating to 110-130° C., dehydrating and blending under vacuum, and cooling to room temperature to obtain a semi-finished product; S2-2: Add the above semi-finished product into a planetary mixer, and then add methyl tri(methyl isobutyl ketone oxime), methyl tri(isopropenyloxy) silane, N-methylimidazole, γ-aminopropyl trimethoxysilane, N-2-aminoethyl-3-aminopropyl trimethoxysilane and dibutyl tin dilaurate in sequence, and after sufficient reaction under vacuum environment, obtain the finished product.

[0021] Example 2 A ketoxime quick-drying neutral silicone door and window sealant, comprising the following raw materials and weight proportions: 35 parts of α,ω-dihydroxypolysiloxane with a viscosity of 15000cp, 5 parts of dimethyl silicone oil with a viscosity of 450cp, 45 parts of modified filler, 4 parts of tetrakis(methyl isobutyl ketone oxime)silane, 1 part of methyltri(isopropenyloxy)silane, 0.4 parts of N-methylimidazole, 1.5 parts of γ-aminopropyltriethoxysilane and N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane in a mass ratio of 1:1, and 0.015 parts of dibutyltin dilaurate.

[0022] Preparation of a ketoxime quick-drying neutral silicone door and window sealant, comprising the following steps: S2-1: adding the weight portions of α,ω-dihydroxypolysiloxane, dimethyl silicone oil and modified filler into a kneader, heating to 110-130° C., dehydrating and blending under vacuum, and cooling to room temperature to obtain a semi-finished product; S2-2: Add the above semi-finished product into a planetary mixer, and then add tetra(methyl isobutyl ketone oxime) silane, methyl tri(isopropenyloxy) silane, N-methylimidazole, γ-aminopropyl triethoxysilane, N-(2-aminoethyl)-3-aminopropyl methyl dimethoxysilane and dibutyl tin dilaurate in sequence, and after sufficient reaction under vacuum environment, obtain the finished product.

[0023] Example 3 A ketoxime quick-drying neutral silicone door and window sealant, comprising the following raw materials and weight proportions: 50 parts of α,ω-dihydroxypolysiloxane with a viscosity of 20000cp, 15 parts of dimethyl silicone oil with a viscosity of 100cp, 45 parts of modified filler, 4.8 parts of vinyl triacetone oxime silane, 1.2 parts of methyl tri(isopropyleneoxy) silane, 0.8 parts of N-methylimidazole, 2 parts of γ-aminopropyltriethoxysilane and 3-diethylenetriaminopropylmethyldimethoxysilane in a mass ratio of 1:1, and 0.03 parts of dibutyltin dilaurate.

[0024] Preparation of a ketoxime quick-drying neutral silicone door and window sealant, comprising the following steps: S2-1: adding the weight portions of α,ω-dihydroxypolysiloxane, dimethyl silicone oil and modified filler into a kneader, heating to 110-130° C., dehydrating and blending under vacuum, and cooling to room temperature to obtain a semi-finished product; S2-2: Add the above semi-finished product into a planetary mixer, and then add vinyl triacetone oxime silane, methyl tri(isopropenyloxy) silane, N-methylimidazole, γ-aminopropyl triethoxysilane, 3-diethylenetriaminopropyl methyldimethoxysilane and dibutyltin dilaurate in sequence, and after sufficient reaction under vacuum environment, obtain the finished product.

[0025] Comparative Example 1 A ketoxime quick-drying neutral silicone door and window sealant, comprising the following raw materials and weight proportions: 100 parts of α,ω-dihydroxypolysiloxane with a viscosity of 20000cp, 3 parts of dimethyl silicone oil, 100 parts of nano calcium carbonate, 5 parts of heavy calcium carbonate, 4 parts of methyl tributylidene oxime silane, 2 parts of vinyl tributylidene oxime silane, 2.5 parts of γ-aminopropyltriethoxysilane, and 0.05 parts of dibutyltin diacetate.

[0026] Preparation of a ketoxime quick-drying neutral silicone door and window sealant, comprising the following steps: S2-1: adding the weight portions of α,ω-dihydroxypolysiloxane, dimethyl silicone oil, nano calcium carbonate and heavy calcium carbonate into a kneader, heating to 110-130° C., dehydrating and blending under vacuum, and cooling to room temperature to obtain a semi-finished product; S2-2: Add the above semi-finished product into a planetary mixer, and then add methyl tributylacetoximate silane, vinyl tributylacetoximate silane, and dibutyltin diacetate of γ-aminopropyltriethoxysilane in turn, and after sufficient reaction under vacuum, obtain the finished product.

[0027] Comparative Example 2 A ketoxime quick-drying neutral silicone door and window sealant, comprising the following raw materials and weight proportions: 100 parts of α,ω-dihydroxy polysiloxane with a viscosity of 10000cp, 3 parts of dimethyl silicone oil, 100 parts of nano calcium carbonate, 6 parts of methyl tributylacetoximate silane, 2 parts of vinyl tributylacetoximate silane, 3 parts of γ-aminopropyl triethoxysilane and N-(β-aminoethyl)-γ-aminopropyl trimethoxy(ethyl)silane in a ratio of 1:1, and 0.05 parts of chelated tin Preparation of a ketoxime quick-drying neutral silicone door and window sealant, comprising the following steps: S2-1: adding the weight portions of α,ω-dihydroxypolysiloxane, dimethyl silicone oil and nano calcium carbonate into a kneader, heating to 110-130° C., dehydrating and blending under vacuum conditions, and cooling to room temperature to obtain a semi-finished product; S2-2: Add the above semi-finished product into a planetary mixer, and then add methyl tributylacetoximate silane, vinyl tributylacetoximate silane, γ-aminopropyl triethoxysilane, N-(β-aminoethyl)-γ-aminopropyl trimethyl(ethyl)oxysilane, and chelated tin in sequence, and after sufficient reaction under vacuum environment, obtain the finished product.

[0028] The performance of the silane-modified polyether sealants prepared in Examples 1 to 3 and Comparative Examples 1 to 2 was tested, and the results are shown in Table 1.

[0029] Table 1 Performance test of door and window sealants Surface drying time (min) Curing depth (24h / mm) Consistency (cm) Thermal storage stability Example 1 23 Practical 8.3 No thickening, no obvious change in solidification Example 2 25 Practical 8.5 No thickening, no obvious change in solidification Example 3 20 Practical 8.2 No thickening, no obvious change in solidification Comparative Example 1 45 2 8.2 No thickening, extended curing time Comparative Example 2 33 2 8.4 Thickening, curing, no obvious changes Among them, the surface drying time is tested according to GB / T13477; for the curing depth test, a 10mm thick rubber strip is punched out, which is cut after 24 hours to measure its radius after curing; and the consistency test uses a putty consistency meter.

[0030] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A ketoxime quick-drying neutral silicone door and window sealant, characterized in that: The composition comprises the following parts by weight: 35-50 parts of α,ω-dihydroxy polysiloxane; 0-20 parts of dimethyl silicone oil; 40-50 parts of modified filler; Compound silane crosslinking agent 4-6 parts; Curing accelerator 0.01 to 1 part; 1-2 parts of silane coupling agent; Catalyst 0.005-0.03 parts; The modified filler surface is modified and prepared according to the following method: S1-1: Add calcium carbonate and stabilizer to the aqueous solution in sequence, disperse evenly by centrifugation, control the temperature at 50-60°C, and keep warm for 30 minutes to obtain a nano calcium carbonate suspension; the stabilizer is sodium nitrilotriacetate; the amount thereof is 1-2% of the dry mass of calcium carbonate; S1-2: After the modifier is heated and melted in an aqueous solution, an emulsifier is added, and the mixture is stirred for 10 to 30 minutes to obtain a modifier emulsion; the modifier is lauric acid, and the total amount thereof is 2.0 to 3.0% of the dry mass of calcium carbonate; the emulsifier is diglycerol polypropylene glycol ether, and the amount thereof is 7 to 20% of the total amount of the modifier; S1-3: Add the nano calcium carbonate suspension obtained in S1-1 to the modifier emulsion, stir thoroughly for 30 to 60 minutes, and then filter press to dehydrate, dry, and grind to obtain the modified filler.

2. A ketoxime quick-drying neutral silicone door and window sealant as claimed in claim 1, characterized in that: The compound silane crosslinking agent is a compound of one or more of tetrakis(methyl isobutyl ketone oxime)silane, vinyl triacetone oxime silane, methyl tris(methyl isobutyl ketone oxime) and methyl tris(isopropyleneoxy)silane; in terms of mass ratio, the compounding ratio is (2-3):(0.5-1).

3. A ketoxime quick-drying neutral silicone door and window sealant as claimed in claim 1, characterized in that: The curing accelerator is N-methylimidazole.

4. A ketoxime quick-drying neutral silicone door and window sealant as claimed in claim 1, characterized in that: The silane coupling agent comprises at least one monoaminosilane coupling agent and at least one polyaminosilane coupling agent, and the mass ratio of the monoaminosilane coupling agent to the polyaminosilane coupling agent is 1:(1-1.5); wherein the monoaminosilane coupling agent is one or more of γ-aminopropyltrimethoxysilane or γ-aminopropyltriethoxysilane; wherein the polyaminosilane coupling agent is one or more of N-2-aminoethyl-3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane, and 3-diethylenetriaminopropylmethyldimethoxysilane.

5. The ketoxime quick-drying neutral silicone door and window sealant according to claim 1, characterized in that: The viscosity of the α,ω-dihydroxy polysiloxane is 5000-20000 mPa.s, and the viscosity of the dimethyl silicone oil is 100-1000 mPa.s.

6. A ketoxime quick-drying neutral silicone door and window sealant as claimed in claim 1, characterized in that: The catalyst is an organic tin catalyst.

7. A method for preparing a ketoxime quick-drying neutral silicone door and window sealant according to any one of claims 1 to 6, characterized in that: The method comprises the following preparation steps: S2-1: adding the weight portions of α,ω-dihydroxypolysiloxane, dimethyl silicone oil and modified filler into a kneader, heating to 110-130° C., dehydrating and blending under vacuum, and cooling to room temperature to obtain a semi-finished product; S2-2: Add the above semi-finished product into a planetary mixer, and then add the compound silane cross-linking agent, curing accelerator, silane coupling agent and catalyst in sequence, and after sufficient reaction under vacuum environment, obtain the finished product.