Antibacterial mildew-proof coloring agent for silicone adhesive and preparation method of antibacterial mildew-proof coloring agent

Abstract

The invention belongs to the technical field of assistants for silicone rubber, and particularly relates to an antibacterial mildew-proof coloring agent for a silicone adhesive and a preparation method of the antibacterial mildew-proof coloring agent. The preparation method comprises the following steps: (1) adding inorganic toner, silicate ester and dimethyl octadecyl [3-(trimethoxysilyl) propyl] ammonium chloride into a solvent, uniformly stirring and mixing, heating to 40-80 DEG C, then dropwise adding ammonia water, stirring for reaction, and performing vacuum drying after the reaction is completed to obtain quaternary ammonium salt modified TQ silicon resin coated inorganic toner; and (2) uniformly mixing and dispersing the obtained quaternary ammonium salt modified TQ silicon resin coated inorganic toner and hydroxyl silicone oil to obtain the antibacterial mildew-proof coloring agent for the silicone adhesive. According to the invention, quaternary ammonium salt modified TQ silicon resin is used for coating and modifying the inorganic toner, so that the coloring effect can be obviously improved, and the silicone adhesive is endowed with obvious antibacterial and mildew-proof characteristics.

Description

Technical Field

[0001] The invention belongs to the technical field of silicone rubber additives, and specifically relates to an antibacterial and anti-mildew colorant for silicone rubber and a preparation method thereof. Background Art

[0002] Silicone adhesive, also known as silicone rubber, is widely used in the fields of bonding, caulking, jointing, sealing, waterproofing, and reinforcement in construction engineering and decoration. Silicone adhesive itself is colorless. In order to give silicone adhesive different colors, color powder needs to be added to improve its color richness. However, due to the strong hydrophobic and oleophobic properties of silicone adhesive, the dispersion effect of pure color powder in silicone adhesive is poor. The color powder is difficult to be wetted and dispersed by the silicone adhesive base material, resulting in the aggregation of color powder and the decrease of coloring strength.

[0003] In order to improve the dispersion effect of toner in silicone adhesive base material, the industry generally mixes toner with silicone plasticizer to prepare colorant, so as to achieve the effect of pre-wetting the toner. For example, patent CN 114149767 A discloses a weather-resistant and heat-resistant inorganic silicone adhesive color paste, which includes the following components by mass: 40-50 parts of silicone resin, 40-60 parts of composite inorganic pigment, 10-15 parts of plasticizer, 5-7 parts of wetting agent, 2-5 parts of dispersant, and 0.5-1 part of silane coupling agent; the composite inorganic pigment includes one or more of titanium chromium pigment, titanium nickel pigment and cobalt pigment; the silicone resin includes dihydroxy polysiloxane and / or dodecamethylcyclohexasiloxane. By using dihydroxy polysiloxane and / or dodecamethylcyclohexasiloxane in combination with silane coupling agent, the dispersion uniformity of composite inorganic pigment is improved. However, the plasticizer used is non-reactive polydimethylsiloxane, which has a weak binding force with the color paste. During the mixing process with the silicone adhesive base, it is still impossible to avoid the aggregation of color powder; at the same time, the low-viscosity polydimethylsiloxane has an adverse effect on the strength of the silicone adhesive.

[0004] In addition, silicone adhesive is easily attacked by microorganisms when used in a humid environment, which can cause mold, discoloration, and blackening. In order to give silicone adhesive antibacterial and antifungal properties, inorganic or organic antibacterial and antifungal agents are generally added to achieve the corresponding antibacterial and antifungal effects. However, the addition of antibacterial and antifungal agents also needs to consider the dispersibility effect in the silicone adhesive system and the impact on the mechanical strength of the silicone adhesive. Summary of the invention

[0005] In view of the shortcomings and deficiencies of the above prior art, the primary purpose of the present invention is to provide a method for preparing an antibacterial and antifungal colorant for silicone adhesive.

[0006] Another object of the present invention is to provide an antibacterial and antifungal colorant prepared by the above method.

[0007] Another object of the present invention is to provide the use of the above-mentioned antibacterial and antifungal colorant in dealcoholized silicone adhesive.

[0008] The purpose of the present invention is achieved through the following technical solutions:

[0009] A method for preparing an antibacterial and antifungal colorant for silicone adhesive comprises the following preparation steps:

[0010] (1) adding an inorganic color powder, a silicate and dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride to a solvent and stirring to mix uniformly, heating to 40 to 80° C., then dropping ammonia water and stirring to react, and vacuum drying after the reaction is completed to obtain a quaternary ammonium salt-modified TQ silicone resin-coated inorganic color powder;

[0011] (2) The obtained quaternary ammonium salt-modified TQ silicone resin-coated inorganic color powder is mixed and dispersed evenly with hydroxy silicone oil to obtain an antibacterial and antifungal colorant for silicone glue.

[0012] Preferably, the inorganic color powder includes carbon powder, titanium dioxide, zinc oxide powder or iron oxide series color powder.

[0013] Preferably, the silicate is methyl orthosilicate, ethyl orthosilicate, propyl orthosilicate or butyl orthosilicate.

[0014] Preferably, the inorganic color powder, silicate and dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride are added in a mass ratio of 100:10-30:10-30.

[0015] Preferably, the solvent is methanol, ethanol or propanol.

[0016] Preferably, the mass concentration of the ammonia water is 25% to 28%, and the amount of ammonia water added is 10% to 50% of the total mass of the silicate and dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride.

[0017] Preferably, the hydroxyl content of the hydroxy silicone oil is 0.5% to 10% (wt.%) and the viscosity is 15 to 200 mm 2 / s(25℃).

[0018] Preferably, the mass ratio of the quaternary ammonium salt modified TQ silicone resin coated inorganic color powder to the hydroxy silicone oil is 100:50-200.

[0019] More preferably, the method for uniformly dispersing the quaternary ammonium salt-modified TQ silicone resin-coated inorganic colorant and hydroxy silicone oil is as follows: adding the quaternary ammonium salt-modified TQ silicone resin-coated inorganic colorant and hydroxy silicone oil to methylcyclosiloxane, heating and stirring for homogenization, and then vacuum removing the methylcyclosiloxane to obtain an antibacterial and antifungal colorant for silicone glue.

[0020] Preferably, the methylcyclosiloxane is hexamethylcyclotrisiloxane (D3), octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5) or a dimethylsiloxane mixed ring (DMC); the amount of the methylcyclosiloxane added is 50% to 200% of the mass of the hydroxy silicone oil; the temperature of the heating and stirring for homogenization treatment is 60 to 100° C., and the time is 1 to 4 hours.

[0021] An antibacterial and anti-mildew colorant for silicone adhesive is prepared by the method.

[0022] Application of the above antibacterial and antifungal colorant in dealcoholized silicone adhesive.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] (1) The present invention adopts quaternary ammonium salt-modified TQ silicone resin to coat and modify the inorganic color powder. On the one hand, TQ silicone resin has strong adhesion to the inorganic color powder and good compatibility with the silicone adhesive base material, which can effectively improve the dispersion effect of the inorganic color powder in the silicone adhesive base material, reduce the aggregation of the color powder, and improve the coloring effect; on the other hand, the inorganic color powder is coated with quaternary ammonium salt, and its cationic properties can significantly reduce the attraction and agglomeration between the color powder particles, thereby improving the dispersion effect; on the other hand, the introduction of quaternary ammonium salt can give the silicone adhesive obvious antibacterial and antifungal properties.

[0025] (2) The antibacterial and antifungal colorant of the present invention uses hydroxy silicone oil as a plasticizer, which can directly participate in the chemical cross-linking reaction of the dealcoholized silicone adhesive and has no adverse effect on the mechanical properties of the dealcoholized silicone adhesive.

[0026] (3) The present invention further adds the quaternary ammonium salt-modified TQ silicone resin-coated inorganic color powder and hydroxy silicone oil into methylcyclosiloxane and heats and stirs to perform a homogenization treatment. Through the swelling effect of methylcyclosiloxane on the TQ silicone resin and the dissolving effect of hydroxy silicone oil on the hydroxy silicone oil, the formation of a semi-interpenetrating network of the hydroxy silicone oil in the TQ silicone resin coating can be significantly promoted, thereby better forming a reinforcing structure in the process of participating in the chemical crosslinking reaction of the dealcoholized silicone glue, thereby achieving a good reinforcement effect. DETAILED DESCRIPTION

[0027] The present invention is further described in detail below in conjunction with examples, but the embodiments of the present invention are not limited thereto.

[0028] Example 1

[0029] A method for preparing an antibacterial and antifungal colorant for silicone adhesive comprises the following preparation steps:

[0030] (1) 150 g of methanol was added to a four-necked flask, and then 100 g of carbon black powder, 20 g of ethyl orthosilicate and 20 g of dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride were added and stirred to mix evenly, and the temperature was raised to 50° C., and then 10 g of 25% ammonia water was added dropwise and stirred to react for 5 h. After the reaction was completed, vacuum rotary evaporation and drying were performed to obtain quaternary ammonium salt-modified TQ silicone resin-coated carbon black powder.

[0031] (2) 100 g of DMC was added to a three-necked flask, followed by 100 g of quaternary ammonium salt-modified TQ silicone resin coated carbon black powder and 100 g of a hydroxyl content of 5% (wt.%) and a viscosity of 60 mm 2 / s (25℃) hydroxy silicone oil was heated to 80℃ and stirred for 2h for homogenization, then vacuum evaporated to remove DMC, cooled to room temperature, and obtained a viscosity of 2650mm 2 / s antibacterial and antifungal colorant for silicone adhesive.

[0032] Example 2

[0033] A method for preparing an antibacterial and antifungal colorant for silicone adhesive comprises the following preparation steps:

[0034] (1) 150 g of ethanol was added to a four-necked flask, and then 100 g of carbon black powder, 10 g of ethyl orthosilicate and 30 g of dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride were added and stirred to mix evenly, and the temperature was raised to 70° C., and then 10 g of 28% ammonia water was added dropwise and stirred to react for 4 h. After the reaction was completed, vacuum rotary evaporation was performed to obtain quaternary ammonium salt-modified TQ silicone resin-coated carbon black powder.

[0035] (2) Add 50g of DMC into a three-necked flask, then add 50g of quaternary ammonium salt-modified TQ silicone resin coated carbon black powder and 100g of a hydroxyl content of 5% (wt.%) and a viscosity of 60mm 2 / s (25℃) hydroxy silicone oil was heated to 60℃ and stirred for 4h for homogenization, then vacuum evaporation was performed to remove DMC, and the mixture was cooled to room temperature to obtain a viscosity of 1600mm 2 / s antibacterial and antifungal colorant for silicone adhesive.

[0036] Example 3

[0037] A method for preparing an antibacterial and antifungal colorant for silicone adhesive comprises the following preparation steps:

[0038] (1) 150 g of isopropanol was added to a four-necked flask, and then 100 g of carbon black powder, 30 g of ethyl orthosilicate and 10 g of dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride were added and stirred to mix evenly, and the temperature was raised to 80° C., and then 15 g of 25% ammonia water was added dropwise and stirred to react for 5 h. After the reaction was completed, vacuum rotary evaporation and drying were performed to obtain quaternary ammonium salt-modified TQ silicone resin-coated carbon black powder.

[0039] (2) 100 g of DMC was added to a three-necked flask, followed by 100 g of quaternary ammonium salt-modified TQ silicone resin coated carbon black powder and 50 g of a hydroxyl content of 5% (wt.%) and a viscosity of 60 mm 2 / s (25℃) hydroxy silicone oil was heated to 100℃ and stirred for 3h for homogenization, then vacuum evaporation was performed to remove DMC, and the mixture was cooled to room temperature to obtain a viscosity of 4700mm 2 / s antibacterial and antifungal colorant for silicone adhesive.

[0040] Example 4

[0041] A method for preparing an antibacterial and antifungal colorant for silicone adhesive comprises the following preparation steps:

[0042] (1) 150 g of methanol was added to a four-necked flask, and then 100 g of titanium dioxide, 20 g of methyl orthosilicate and 20 g of dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride were added and stirred to mix evenly, and the temperature was raised to 40° C., and then 15 g of 25% ammonia water was added dropwise and stirred to react for 6 h. After the reaction was completed, vacuum rotary evaporation and drying were performed to obtain quaternary ammonium salt-modified TQ silicone resin-coated titanium dioxide.

[0043] (2) Add 100g of D5 into a three-necked flask, then add 100g of quaternary ammonium salt-modified TQ silicone resin-coated titanium dioxide and 100g of a hydroxyl content of 2% (wt.%) and a viscosity of 100mm. 2 / s (25℃) hydroxy silicone oil was heated to 90℃ and stirred for 3h for homogenization, then vacuum evaporated to remove D5, cooled to room temperature, and obtained a viscosity of 2860mm 2 / s antibacterial and antifungal colorant for silicone adhesive.

[0044] Example 5

[0045] A method for preparing an antibacterial and antifungal colorant for silicone adhesive comprises the following preparation steps:

[0046] (1) 150 g of methanol was added to a four-necked flask, and then 100 g of iron oxide color powder, 20 g of propyl orthosilicate and 20 g of dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride were added and stirred to mix evenly, and the temperature was raised to 50° C., and then 15 g of 25% ammonia water was added dropwise and stirred to react for 4 h. After the reaction was completed, vacuum rotary evaporation and drying were performed to obtain quaternary ammonium salt-modified TQ silicone resin-coated iron oxide color powder.

[0047] (2) Add 100g of D4 into a three-necked flask, then add 100g of quaternary ammonium salt-modified TQ silicone resin coated iron oxide toner and 100g of a hydroxyl content of 6% (wt.%) and a viscosity of 40mm. 2 / s (25℃) hydroxy silicone oil, heated to 80℃ and stirred for 1h for homogenization, then vacuum evaporated to remove D4, cooled to room temperature, and obtained a viscosity of 2520mm 2 / s antibacterial and antifungal colorant for silicone adhesive.

[0048] Example 6

[0049] A method for preparing an antibacterial and antifungal colorant for silicone adhesive, compared with Example 1, wherein DMC is not added in step (2) for homogenization treatment, and the method comprises the following preparation steps:

[0050] Step (1) is the same as in Example 1.

[0051] (2) 100 g of quaternary ammonium salt-modified TQ silicone resin coated carbon black powder and 100 g of a 5% (wt.%) hydroxyl content and a viscosity of 60 mm 2 / s (25 ° C) hydroxy silicone oil was heated to 80 ° C and stirred for 2 hours to obtain a viscosity of 840mm 2 / s antibacterial and antifungal colorant for silicone adhesive.

[0052] Example 7

[0053] A method for preparing an antibacterial and antifungal colorant for silicone adhesive, compared with Example 2, wherein DMC is not added in step (2) for homogenization treatment, and the method comprises the following preparation steps:

[0054] Step (1) is the same as in Example 1.

[0055] (2) 50 g of quaternary ammonium salt-modified TQ silicone resin coated carbon black powder and 100 g of hydroxyl content of 5% (wt.%) and viscosity of 60 mm 2 / s (25 ° C) hydroxy silicone oil was heated to 60 ° C and stirred for 4 hours to obtain a viscosity of 510mm 2 / s antibacterial and antifungal colorant for silicone adhesive.

[0056] Example 8

[0057] A method for preparing an antibacterial and antifungal colorant for silicone adhesive, compared with Example 3, wherein DMC is not added in step (2) for homogenization treatment, and the method comprises the following preparation steps:

[0058] Step (1) is the same as in Example 1.

[0059] (2) 100 g of quaternary ammonium salt-modified TQ silicone resin coated carbon black powder and 50 g of a hydroxyl content of 5% (wt.%) and a viscosity of 60 mm 2 / s (25 ° C) hydroxy silicone oil was heated to 100 ° C and stirred for 3 hours to obtain a viscosity of 2150mm 2 / s antibacterial and antifungal colorant for silicone adhesive.

[0060] Comparative Example 1

[0061] A method for preparing an antibacterial and antifungal colorant for silicone adhesive, compared with Example 6, uses unmodified carbon black powder, and includes the following preparation steps:

[0062] 100g of carbon black powder and 100g of a 5% (wt.%) hydroxyl content and a viscosity of 60mm 2 / s (25 ° C) hydroxy silicone oil was heated to 80 ° C and stirred for 2 hours to obtain a viscosity of 750mm 2 / s antibacterial and antifungal colorant for silicone adhesive.

[0063] The coloring strength of the colorants obtained in the above Examples 1 to 3 and Examples 6 to 8 (reference GB / T 3780.6-2016, using the ratio of the light reflectance of the industrial coloring reference carbon black (ITRB) to the test sample, based on the effective mass of the carbon black powder as 0.1g) and the application performance (antibacterial and mildew resistance (reference QB / T 2591-2003, test antibacterial grade and mildew growth grade); mechanical properties refer to GB / T 528-2009 to test tensile strength and elongation at break) in dealcoholized silicone rubber (100 parts of hydroxy silicone oil, 50 parts of calcium carbonate, 20 parts of fumed silica, 10 parts of silane coupling agent KH-560, 10 parts of colorant, 1 part of titanate catalyst) are shown in Table 1 below.

[0064] Table 1

[0065] Test sample Tinting Strength Antimicrobial grade Mildew Level Tensile Strength Elongation at break Example 1 96.6％ ≥99％ Level 0 5.2MPa 460％ Example 2 97.1％ ≥99％ Level 0 4.5MPa 410％ Example 3 96.0％ ≥99％ Level 0 5.6MPa 495％ Example 6 96.7％ ≥99％ Level 0 4.6MPa 415％ Example 7 96.8％ ≥99％ Level 0 4.0MPa 382％ Example 8 96.0％ ≥99％ Level 0 4.7MPa 420％ Comparative Example 1 88.5％ No antibacterial effect No antifungal effect 3.8MPa 346％

[0066] It can be seen from the results in Table 1 that the present invention can significantly improve the dispersion effect of inorganic toner in hydroxy silicone oil and the final silicone glue by coating and modifying inorganic toner with quaternary ammonium salt TQ silicone resin, reduce the attraction and agglomeration between toner particles, thereby improving the tinting strength of the colorant and improving the mechanical strength of the silicone glue. And it can give the obtained silicone glue good antibacterial and mildew-proof effects. It can be seen from the comparison results of Examples 1 to 3 with Examples 6 to 8 that by further adding the quaternary ammonium salt modified TQ silicone resin coated inorganic toner and hydroxy silicone oil to methyl cyclosiloxane for heating and stirring for homogenization treatment, the mechanical properties of the obtained silicone glue can be improved by more than 10%. The reason is that the swelling effect of methyl cyclosiloxane on TQ silicone resin and the dissolving effect on hydroxy silicone oil during the homogenization process can significantly promote the formation of a semi-interpenetrating network of hydroxy silicone oil in the TQ silicone resin coating layer, thereby better forming a reinforcing structure in the chemical crosslinking reaction process of the dealcohol silicone glue, and achieving a good reinforcing effect.

[0067] The above embodiments are preferred implementation modes of the present invention, but the implementation modes of the present invention are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be equivalent replacement methods and are included in the protection scope of the present invention.

Claims

1. A method for preparing an antibacterial and antifungal colorant for silicone adhesive, characterized in that: The method comprises the following preparation steps: (1) adding an inorganic color powder, a silicate and dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride to a solvent and stirring to mix uniformly, heating to 40 to 80° C., then dropping ammonia water and stirring to react, and vacuum drying after the reaction is completed to obtain a quaternary ammonium salt-modified TQ silicone resin-coated inorganic color powder; (2) The obtained quaternary ammonium salt-modified TQ silicone resin-coated inorganic color powder is mixed and dispersed evenly with hydroxy silicone oil to obtain an antibacterial and antifungal colorant for silicone glue.

2. The method for preparing an antibacterial and antifungal colorant for silicone adhesive according to claim 1, characterized in that: The inorganic color powder includes carbon powder, titanium dioxide, zinc oxide powder or iron oxide series color powder; the silicate is methyl orthosilicate, ethyl orthosilicate, propyl orthosilicate or butyl orthosilicate.

3. The method for preparing an antibacterial and antifungal colorant for silicone adhesive according to claim 1, characterized in that: The inorganic color powder, silicate and dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride are added in a mass ratio of 100:10-30:10-30.

4. The method for preparing an antibacterial and antifungal colorant for silicone adhesive according to claim 1, characterized in that: The solvent is methanol, ethanol or propanol.

5. The method for preparing an antibacterial and antifungal colorant for silicone adhesive according to claim 1, characterized in that: The mass concentration of the ammonia water is 25% to 28%, and the amount of the ammonia water added is 10% to 50% of the total mass of the silicate and dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride.

6. The method for preparing an antibacterial and antifungal colorant for silicone adhesive according to claim 1, characterized in that: The hydroxy silicone oil has a hydroxy content of 0.5% to 10% and a viscosity of 15 to 200 mm 2 / s; the mass ratio of the quaternary ammonium salt modified TQ silicone resin coated inorganic color powder and the hydroxy silicone oil is 100:50-200.

7. The method for preparing an antibacterial and antifungal colorant for silicone adhesive according to claim 1, characterized in that: The method for uniformly dispersing the quaternary ammonium salt modified TQ silicone resin coated inorganic color powder and hydroxy silicone oil is as follows: adding the quaternary ammonium salt modified TQ silicone resin coated inorganic color powder and hydroxy silicone oil to methyl cyclosiloxane, heating and stirring for homogenization, and then vacuum removing the methyl cyclosiloxane to obtain the antibacterial and antifungal colorant for silicone glue.

8. The method for preparing an antibacterial and antifungal colorant for silicone adhesive according to claim 7, characterized in that: The methylcyclosiloxane is a mixed ring of hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane or dimethylsiloxane; the added amount of the methylcyclosiloxane is 50% to 200% of the mass of the hydroxy silicone oil; the temperature of the heating and stirring for homogenization treatment is 60 to 100° C., and the time is 1 to 4 hours.

9. An antibacterial and antifungal colorant for silicone adhesive, characterized in that: It is prepared by the method according to any one of claims 1 to 8.

10. Use of the antibacterial and antifungal colorant according to claim 9 in dealcoholized silicone adhesive.