Solvent-free antibacterial floor coating and preparation method thereof

Abstract

The invention belongs to the technical field of floor coatings, and particularly relates to a solvent-free antibacterial floor coating and a preparation method thereof. The solvent-free antibacterial terrace coating provided by the invention comprises a component A and a component B. The preparation method comprises the step of uniformly mixing the component A and the component B according to the mass ratio of (2.5-4): 1, so that the solvent-free antibacterial terrace coating can be used. The component A comprises the following components in parts by mass: 60-75 parts of polyol; 20-40 parts by mass of pigment and filler; and 4-8 parts by mass of an auxiliary agent. The component B is an isocyanate-terminated prepolymer containing an antibacterial group, and the component B is prepared by the following steps: placing dehydrated polyol and a catalyst dibutyltin dilaurate in a reaction container, adding isophorone diisocyanate and a quaternary phosphonium salt compound in a nitrogen protective atmosphere, reacting for 1 hour, and then adding dimethylolpropionic acid to obtain the component B. The floor coating prepared by the invention is high in solid content, low in VOC (volatile organic compound) emission, environment-friendly and long-acting in antibacterial property.

Description

Technical Field

[0001] The invention belongs to the technical field of floor coatings, and in particular relates to a solvent-free antibacterial floor coating and a preparation method thereof. Background Art

[0002] Floor coatings not only decorate the floor, but also provide the floor with functions such as dust and moisture proof, wear resistance, pressure resistance, and easy cleaning. Therefore, they have been widely used in many industries.

[0003] Common floor coatings mainly include the following three categories: oil-based, water-based and solvent-free. Although oil-based floor coatings are excellent in abrasion resistance, pressure resistance and solvent resistance, they are not environmentally friendly because they contain high volatile organic compounds (VOC) and emit unpleasant odors. In contrast, water-based floor coatings are more environmentally friendly, but they have problems such as low film quality and difficulty in construction. Solvent-free floor coatings can not only provide high-quality coatings, but also have low VOC emissions.

[0004] On the other hand, as people's requirements for environmental hygiene increase, the market demand for floor coatings with antibacterial functions is growing. Traditional antibacterial coatings usually achieve antibacterial effects by adding antibacterial agents, such as quaternary ammonium compounds. Quaternary ammonium salts have the advantages of high broad-spectrum antibacterial properties and low bacterial resistance. The antibacterial mechanism is that the cations in quaternary ammonium salts can interact with the negatively charged bacterial cell membrane and further combine with the phospholipid bilayer in the cell membrane, thereby destroying the cell membrane structure, causing the leakage of intracellular substances, and ultimately killing the bacteria.

[0005] This type of antibacterial coating, which is made by directly adding antibacterial ingredients to the coating, is simple to prepare and has a good initial antibacterial effect. However, over time, the antibacterial effect will weaken as the active ingredients of the antibacterial agent are gradually released or migrate out of the coating. Summary of the invention

[0006] In view of the shortcomings of the prior art, the present invention provides a solvent-free antibacterial floor coating and a preparation method thereof. The purpose of the present invention is to ensure that the floor coating has excellent stability and adhesion while also having long-lasting and efficient antibacterial properties and excellent environmental protection.

[0007] The solvent-free antibacterial floor coating provided by the present invention comprises a component A and a component B. The preparation method comprises uniformly mixing the component A and the component B in a mass ratio of (2.5-4):1, and then the coating can be used.

[0008] The component A comprises: 60 to 75 parts by weight of polyol; 20 to 40 parts by weight of pigment and filler; and 4 to 8 parts by weight of auxiliary agent.

[0009] Among them, the B component is a terminal isocyanate prepolymer containing an antibacterial group, and the preparation of the B component includes the following steps: adding a polyol into a 200 ml three-necked flask, stirring at 100-120° C. for 30 minutes, and then transferring it to a reactor, keeping it for 4 hours under the conditions of a vacuum degree of -0.10 MPa and a temperature of 200° C., and then cooling it to room temperature and transferring it back to the three-necked flask, adding a catalyst dibutyltin dilaurate, and then heating it to 50-60° C. under the protection of dry nitrogen, adding isophorone diisocyanate and a quaternary phosphonium salt compound, reacting for 1 hour, and then adding dihydroxymethylpropionic acid. After reacting for 2 hours, the B component is obtained.

[0010] As a further optimization scheme, in component A, the polyol is selected from one or more of ethylene glycol, propylene glycol, and glycerol.

[0011] As a further optimization scheme, in component A, the pigment filler is selected from one or more of 15 to 20 parts of titanium dioxide, 1 to 5 parts of carbon black, 1 to 3 parts of silicon dioxide, 10 to 25 parts of talc, and 5 to 10 parts of heavy calcium.

[0012] As a further optimization scheme, in component A, the additives include 0.2 to 0.6 parts of a defoamer, 2 to 5 parts of a wetting and leveling agent, and 1.8 to 3 parts of a dispersant, wherein the defoamer can be a polyether-modified polysiloxane-based silicone defoamer, the wetting and leveling agent can be DISPERBYK-344 or DISPERBYK-326, and the dispersant can be DISPERBYK-2014, DISPERBYK-180 or DISPERBYK-2155.

[0013] As a further optimization scheme, the synthesis of component A includes the following steps: 75 parts by mass of polyol, 0.4 parts by mass of defoamer, and 3 parts by mass of dispersant are placed in a high-speed disperser, mechanically stirred for 10 minutes at a speed of 1000-1200 r / min, and then 15 parts by mass of titanium dioxide, 10 parts by mass of talcum powder, and 2 parts by mass of silicon dioxide are added to the disperser in sequence, mechanically stirred for 60 minutes at a speed of 1300-1500 r / min, and finally 2.5 parts by mass of wetting and leveling agent are added and mechanically stirred for 10 minutes at a speed of 1000-1200 r / min to obtain a crude product, and the crude product is filtered through a 300-mesh gauze and packaged to obtain component A.

[0014] As a further optimization scheme, in the process of preparing component B, the polyol is dehydrated for 4 hours at 200°C and a vacuum degree of ≤-0.1 MPa before use.

[0015] As a further optimization scheme, during the preparation of component B, the protective atmosphere is dry nitrogen.

[0016] As a further optimization scheme, the synthesis of the quaternary phosphonium salt compound used in the preparation of component B includes the following steps: first, 1,6-bis(diphenylphosphino)hexane is synthesized using 1,6-dibromohexane and diphenylphosphine as raw materials; then, 1,6-bis(diphenylphosphino)hexane is reacted with p-bromophenol to generate a quaternary phosphonium salt compound.

[0017] As a further optimization scheme, 1,6-bis(diphenylphosphino)hexane and p-bromophenol are heated to react in a solvent of ethylene glycol in the presence of a catalyst of nickel bromide to generate a quaternary phosphonium salt compound.

[0018] As a further optimization scheme, 1,6-bis(diphenylphosphino)hexane and p-bromophenol are added to a reaction vessel in a molar ratio of 1:(4-5), and solvent ethylene glycol and catalyst nickel bromide are added. Under a nitrogen protective atmosphere, the temperature is raised to 160-190° C., and the mixture is stirred at a constant temperature for 10-15 hours, then cooled to room temperature, and the resulting reaction mixture is dissolved in dichloromethane, and then washed alternately with deionized water and anhydrous ethanol for 3-5 times, and the solvent is removed by rotary evaporation. Ether and tetrahydrofuran are used as washing filtrate, and the washing product is stirred and filtered at room temperature to obtain a quaternary phosphonium salt compound.

[0019] Beneficial Effects

[0020] The innovative solvent-free antibacterial floor coating provided by the present invention is a high-solid, low-viscosity coating that does not contain volatile toxic substances such as formaldehyde and benzene, has a solid content of nearly 100%, and does not require the addition of any solvents or diluents during use. The VOC emissions are extremely low, so it is a truly environmentally friendly coating.

[0021] The solvent-free antibacterial floor coating provided by the present invention connects the quaternary phosphonium salt group to the polymer resin through a chemical reaction, so that the polymer resin skeleton has antibacterial properties, which enables the antibacterial coating to exert an antibacterial durability almost as long as the service life of the coating film.

[0022] The solvent-free antibacterial floor coating provided by the present invention has a quaternary phosphonium salt group on the internal polymer chain. Since the atomic radius of P is larger than the atomic radius of N and the corresponding electronegativity is lower, the positive charge of the quaternary phosphonium cation is stronger than that of the quaternary ammonium cation, the attraction to the negatively charged bacterial cell membrane is stronger, and the antibacterial and bactericidal effect is better. DETAILED DESCRIPTION

[0023] The present invention is further illustrated by specific examples below. These examples are exemplary and are intended to illustrate the problem and explain the present invention, but are not intended to be limiting.

[0024] The solvent-free antibacterial floor coating is composed of component A and component B. Component A includes 60-75 parts of polyol, 20-40 parts of pigments and fillers, and 4-8 parts of additives by weight. Polyols mainly include ethylene glycol, propylene glycol, glycerol, etc. Pigments and fillers include one or more of 15-20 parts of titanium dioxide, 1-5 parts of carbon black, 1-3 parts of silicon dioxide, 10-25 parts of talc, and 5-10 parts of heavy calcium. The additives include 0.2-0.6 parts of defoamers, 2-5 parts of wetting and leveling agents, and 1.8-3 parts of dispersants, wherein the defoamer can be a polyether-modified polysiloxane silicone defoamer, the wetting and leveling agent can be DISPERBYK-344 or DISPERBYK-326, and the dispersant can be DISPERBYK-2014, DISPERBYK-180 or DISPERBYK-2155.

[0025] The synthesis of the component A comprises the following steps: placing 75 parts by mass of a polyol, 0.4 parts by mass of a defoamer, and 3 parts by mass of a dispersant in a high-speed disperser, mechanically stirring for 10 minutes at a speed of 1000-1200 r / min, then sequentially adding 15 parts by mass of titanium dioxide, 10 parts by mass of talcum powder, and 2 parts by mass of silicon dioxide into the disperser, mechanically stirring for 60 minutes at a speed of 1300-1500 r / min, and finally adding 2.5 parts by mass of a wetting and leveling agent, mechanically stirring for 10 minutes at a speed of 1000-1200 r / min, to obtain a crude product, filtering the crude product through a 300-mesh gauze and packaging to obtain the component A.

[0026] Component B is the curing agent of component A. The weight ratio of component A to component B is (2.5-4):1. Component A and component B can be used after being evenly mixed.

[0027] The synthesis of the B component includes the following steps: adding a polyol into a 200 ml three-necked flask, stirring at 100-120° C. for 30 minutes, transferring the mixture into a reactor, maintaining the mixture at 200° C. for 4 hours under a vacuum degree of -0.10 MPa, cooling the mixture to room temperature, transferring the mixture back into the three-necked flask, adding a catalyst dibutyltin dilaurate, and subsequently heating the mixture to 50-60° C. under the protection of dry nitrogen, adding isophorone diisocyanate and a quaternary phosphonium salt compound, reacting the mixture for 1 hour, and then adding dimethylolpropionic acid. After reacting the mixture for 2 hours, the B component is obtained.

[0028] The synthesis of the quaternary phosphonium salt compound used in the B component includes the following steps: First, 1,6-dibromohexane and diphenylphosphine are used as raw materials to synthesize 1,6-bis(diphenylphosphino)hexane. 1,6-bis(diphenylphosphino)hexane and p-bromophenol are added to a four-necked flask in a molar ratio of 1:(4-5), and solvent ethylene glycol and catalyst nickel bromide are added. In an atmosphere of dry nitrogen, the temperature is raised to 160-190°C and stirred at a constant temperature for 10-15h. After the reaction is complete and cooled to room temperature, the above-mentioned obtained product is dissolved in dichloromethane, and then washed alternately with deionized water and anhydrous ethanol for 3-5 times, and the solvent is removed by rotary evaporation. Finally, ether and tetrahydrofuran are used as washing filtrate, and the washing product obtained by stirring and filtering at room temperature is the quaternary phosphonium salt compound.

[0029] Example 1

[0030] A solvent-free antibacterial floor coating provided by a preferred embodiment of the present invention is composed of component A and component B. Component A includes, by weight: 75 parts of polyol, 15 parts of titanium dioxide, 10 parts of talc, 2 parts of silicon dioxide, 0.4 parts of defoamer, 3 parts of dispersant, and 2.5 parts of wetting and leveling agent.

[0031] The synthesis of the component A comprises the following steps: placing 75 parts by mass of a polyol, 0.4 parts by mass of a defoamer, and 3 parts by mass of a dispersant in a high-speed disperser, mechanically stirring for 10 minutes at a speed of 1000-1200 r / min, then sequentially adding 15 parts by mass of titanium dioxide, 10 parts by mass of talcum powder, and 2 parts by mass of silicon dioxide into the disperser, mechanically stirring for 60 minutes at a speed of 1300-1500 r / min, and finally adding 2.5 parts by mass of a wetting and leveling agent, mechanically stirring for 10 minutes at a speed of 1000-1200 r / min, to obtain a crude product, filtering the crude product through a 300-mesh gauze and packaging to obtain the component A.

[0032] Component B is the curing agent of component A. The weight ratio of component A to component B is 4:1. Component A and component B can be used after being evenly mixed.

[0033] The synthesis of the B component includes the following steps: adding a polyol into a 200 ml three-necked flask, stirring at 100-120° C. for 30 min, then transferring the mixture into a reactor, maintaining the mixture for 4 h under the conditions of a vacuum degree of -0.10 MPa and a temperature of 200° C., then cooling the mixture to room temperature and then transferring the mixture back into the three-necked flask, adding a catalyst dibutyltin dilaurate, then heating the mixture to 50-60° C. under the protection of dry nitrogen, adding isophorone diisocyanate and a quaternary phosphonium salt compound, reacting the mixture for 1 h, then adding dimethylolpropionic acid, and reacting the mixture for 2 h to obtain the B component.

[0034] Synthesis of the quaternary phosphonium salt compound used in the B component: First, 1,6-dibromohexane and diphenylphosphine are used as raw materials to synthesize 1,6-bis(diphenylphosphino)hexane. 1,6-bis(diphenylphosphino)hexane and p-bromophenol are added to a four-necked flask in a molar ratio of 1:(4-5), and solvent ethylene glycol and catalyst nickel bromide are added. In an atmosphere of dry nitrogen, the temperature is raised to 160-190°C and stirred at a constant temperature for 10-15h. After the reaction is complete and cooled to room temperature, the above-mentioned product is dissolved in dichloromethane, and then washed alternately with deionized water and anhydrous ethanol for 3-5 times, and the solvent is removed by rotary evaporation. Finally, ether and tetrahydrofuran are used as washing filtrate, and the washing product obtained by stirring and filtering at room temperature is the quaternary phosphonium salt compound.

[0035] Example 2

[0036] This embodiment is based on the embodiment 1, and is different from the embodiment 1 in that the component A in this embodiment includes the following components in parts by weight: 65 parts of polyol, 25 parts of titanium dioxide, 5 parts of silicon dioxide, 0.2 parts of defoamer, 1.8 parts of wetting and leveling agent, and 3 parts of dispersant. By weight, the mass ratio of component A to component B is 4:1, and the rest is the same as that in embodiment 1.

[0037] Example 3

[0038] This embodiment is based on Embodiment 1. The difference from Embodiment 1 is that, in this embodiment, the mass ratio of component A to component B is 3:1 by weight, and the rest is the same as Embodiment 1.

[0039] Example 4

[0040] This embodiment is based on Embodiment 1. The difference from Embodiment 1 is that, in this embodiment, the mass ratio of component A to component B is 2.5:1 by weight, and the rest is the same as Embodiment 1.

[0041] Comparative Example 1

[0042] This comparative example is based on Example 1. The difference from Example 1 is that in this comparative example, the mass ratio of component A to component B is 5:1 by weight, and the rest is the same as Example 1.

[0043] Comparative Example 2

[0044] This comparative example is based on Example 1. The difference from Example 1 is that in this comparative example, the mass ratio of component A to component B is 2:1 by weight, and the rest is the same as Example 1.

[0045] Comparative Example 3

[0046] This comparative example is based on Example 1, and the difference from Example 1 is that no quaternary phosphonium salt compound is added when preparing component B. By weight, the mass ratio of component A to component B is 4:1, and the rest is the same as Example 1.

[0047] The above embodiments and comparative examples all produce high-solid, low-viscosity coatings, which contain almost no volatile organic compounds, have a solid content of nearly 100%, and do not require the addition of any solvents or diluents during use. The VOC emissions are extremely low, and therefore are truly environmentally friendly coatings.

[0048] In addition, the antibacterial properties of the coatings prepared in the above embodiments and comparative examples were tested with reference to GB / T 21866-2008 standard. The results are shown in Table 1. The antibacterial properties of each embodiment are better than those of the comparative solution, and have significant advantages in moisture resistance and antibacterial properties.

[0049] Table 1 Antibacterial performance test results

[0050] Example Antibacterial rate Example 1 99.99％ Example 2 99.98％ Example 3 99.95％ Example 4 99.91％ Comparative Example 1 98.89％ Comparative Example 2 96.45％ Comparative Example 3 <90％

[0051] The above embodiments are exemplary, and their purpose is to illustrate the technical concept and features of the present invention so that people familiar with the technology in this field can understand the content of the present invention and implement it accordingly, and they cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for preparing a solvent-free antibacterial floor coating, characterized in that: The solvent-free antibacterial floor coating comprises component A and component B; component A and component B are uniformly mixed in a mass ratio of (2.5-4):1 and then used; The component A comprises: 60-75 parts by weight of polyol; 20-40 parts by weight of pigment and filler; and 4-8 parts by weight of auxiliary agent. The preparation of the B component includes the following steps: placing a polyol and a catalyst dibutyltin dilaurate in a reaction container, adding isophorone diisocyanate and a quaternary phosphonium salt compound under a nitrogen protective atmosphere, heating for reaction, and then adding dimethylol propionic acid and reacting for 2 hours to obtain the B component.

2. The method for preparing the solvent-free antibacterial floor coating according to claim 1, characterized in that: The preparation of the B component comprises the following steps: adding a polyol into a 200 ml three-necked flask, stirring at 100-120° C. for 30 min, transferring the mixture into a reactor, maintaining the mixture at 200° C. and a vacuum degree of -0.10 MPa for 4 h, cooling the mixture to room temperature and then transferring the mixture back into the three-necked flask, adding a catalyst dibutyltin dilaurate, then heating the mixture to 50-60° C. under the protection of dry nitrogen, adding isophorone diisocyanate and a quaternary phosphonium salt compound, reacting the mixture for 1 h, then adding dimethylolpropionic acid, and reacting the mixture for 2 h to obtain the B component; Among them, the weight of polyol accounts for 55% of the total mass of raw materials, the weight of isophorone diisocyanate accounts for 30% of the total mass of raw materials, the weight of quaternary phosphonium salt compound accounts for 5% of the total mass of raw materials, the weight of dimethylol propionic acid accounts for 10% of the total mass of raw materials, and the weight of catalyst dibutyltin dilaurate accounts for 0.1% of the weight of polyol.

3. The method for preparing the solvent-free antibacterial floor coating according to claim 1, characterized in that: In component A, the polyol is selected from one or more of ethylene glycol, propylene glycol, and glycerol; The pigments and fillers in component A include one or more of the following components in parts by weight: 15 to 20 parts of titanium dioxide, 1 to 5 parts of carbon black, 1 to 3 parts of silicon dioxide, 10 to 25 parts of talc, and 5 to 10 parts of heavy calcium.

4. The method for preparing the solvent-free antibacterial floor coating according to claim 1, characterized in that: In the component A, the auxiliary agent includes the following components in parts by weight: 0.2-0.6 parts of defoaming agent, 2-5 parts of wetting and leveling agent, and 1.8-3 parts of dispersing agent, wherein the defoaming agent can be a polyether-modified polysiloxane silicone defoaming agent, the wetting and leveling agent can be DISPERBYK-344 or DISPERBYK-326, and the dispersing agent can be DISPERBYK-2014, DISPERBYK-180 or DISPERBYK-2155.

5. The method for preparing the solvent-free antibacterial floor coating according to claim 1, characterized in that: It includes component A and component B; The component A comprises the following components in parts by weight: 75 parts by weight of polyol; 27 parts by weight of pigment and filler; 5.9 parts by weight of additive; wherein the polyol comprises one or more of ethylene glycol, propylene glycol and glycerol; The pigments and fillers in component A include the following components by weight: 15 parts of titanium dioxide, 10 parts of talc, and 2 parts of silicon dioxide; The auxiliary agent includes the following components in parts by weight: 0.4 parts of defoamer, 3 parts of dispersant, and 2.5 parts of wetting and leveling agent; The synthesis of the component A comprises the following steps: placing 75 parts by mass of a polyol, 0.4 parts by mass of a defoamer, and 3 parts by mass of a dispersant in a high-speed disperser, mechanically stirring for 10 minutes at a speed of 1000-1200 r / min, then sequentially adding 15 parts by mass of titanium dioxide, 10 parts by mass of talc, and 2 parts by mass of silicon dioxide into the disperser, mechanically stirring for 60 minutes at a speed of 1300-1500 r / min, and finally adding 2.5 parts by mass of a wetting and leveling agent, mechanically stirring for 10 minutes at a speed of 1000-1200 r / min, to obtain a crude product, filtering the crude product through a 300-mesh gauze and packaging to obtain the component A.

6. The B component is an isocyanate-terminated prepolymer containing an antibacterial group; the mass ratio of the A component to the B component is 4:1; The method for preparing the solvent-free antibacterial floor coating according to claim 1 is characterized in that: During the preparation of component B, the polyol was dehydrated for 4 h at a temperature of 200° C. and a vacuum degree of ≤-0.1 MPa before use.

7. The method for preparing the solvent-free antibacterial floor coating according to any one of claims 1 to 6, characterized in that: The synthesis of the quaternary phosphonium salt compound used in the preparation process of component B includes the following steps: firstly, 1,6-dibromohexane and diphenylphosphine are used as raw materials to synthesize 1,6-bis(diphenylphosphino)hexane; then, 1,6-bis(diphenylphosphino)hexane is reacted with p-bromophenol to generate the quaternary phosphonium salt compound.

8. The method for preparing the solvent-free antibacterial floor coating according to claim 7, characterized in that: 1,6-Bis(diphenylphosphino)hexane and p-bromophenol are heated and reacted in ethylene glycol as a solvent under the action of nickel bromide as a catalyst to generate a quaternary phosphonium salt compound.

9. The method for preparing the solvent-free antibacterial floor coating according to claim 8, characterized in that: 1,6-bis(diphenylphosphino)hexane and p-bromophenol are added to a reaction vessel in a molar ratio of 1:(4-5), and solvent ethylene glycol and catalyst nickel bromide are added. Under a nitrogen protective atmosphere, the temperature is raised to 160-190°C, and the mixture is stirred at a constant temperature for 10-15 hours, then cooled to room temperature, and the resulting reaction mixture is dissolved in dichloromethane, and then washed alternately with deionized water and anhydrous ethanol for 3-5 times, and the solvent is removed by rotary evaporation. Ether and tetrahydrofuran are used as washing filtrate, and the washing product is stirred and filtered at room temperature to obtain a quaternary phosphonium salt compound.

10. A solvent-free antibacterial floor coating, characterized in that: Prepared according to the preparation method according to any one of claims 1 to 9.