Branched fluoroalkyl short-chain quaternary ammonium salt antibacterial agent

Abstract

The invention discloses a branched fluoroalkyl short-chain quaternary ammonium salt antibacterial agent. The branched fluoroalkyl short-chain quaternary ammonium salt antibacterial agent is formed by combining one or more of compounds shown in a formula I, a formula II and a formula III. The invention has stronger hydrophobic and oleophobic properties, can keep quaternary ammonium salt immobilized in thalli to improve and prolong the bactericidal performance, and obviously reduces the biotoxicity at the same time.

Description

Technical Field

[0001] The invention relates to the technical field of antibacterial compound production, in particular to a branched fluoroalkyl short-chain quaternary ammonium salt antibacterial agent. Background Art

[0002] Since Damark pioneered the field of cationic antimicrobial agents in 1935, quaternary ammonium salts have been widely used in daily life because of their strong bactericidal effect and low biological hazard. The fluorocarbon chain has a very low surface tension and exhibits hydrophobic and oleophobic properties. If the fluorocarbon chain is linked to the quaternary ammonium salt, the fluorocarbon chain can fix the quaternary ammonium salt in the bacteria and enhance the bactericidal effect of the quaternary ammonium salt. At present, linear fluoroalkyl quaternary ammonium salts can only exhibit high bactericidal properties and fluorine surface properties when the number of fluorocarbon groups reaches or exceeds 8. The main reason is that only when the number of linear fluorocarbon groups reaches or exceeds 8 can the fluorocarbon groups form fluorine crystals on the surface of the material, so that the fluorocarbon groups on the surface are arranged regularly, achieving stable fluorine surface properties ( Figure 1 a). When the number of fluorocarbon groups is less than 8, the fluorocarbon groups will be irregularly arranged on the surface of the material, making it difficult to form surface fluorine crystals, which will result in reduced surface stability of fluorine, and the quaternary ammonium salt will not be completely fixed in the bacteria, resulting in reduced antibacterial effect ( Figure 1 b). At present, the quaternary ammonium salt antibacterial agent of the fluoroalkyl chain is a linear fluoroalkyl chain quaternary ammonium salt. CN103572594A describes a trimethoxysilylpropyl-N, N-dipropyl tridecafluorooctyl ammonium chloride antibacterial agent, which exhibits high antibacterial properties. However, perfluorooctyl compounds have high biological toxicity and are banned in many countries. For example: perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS), the EU has partially banned their use in July 2020. The toxicity of short-chain fluoroalkyl compounds is relatively reduced, but it has a small number of fluorocarbon groups, and it is more difficult to form fluorine crystals or fluorine accumulation on the surface, resulting in its fluorine surface properties. The effect is not obvious. Summary of the invention

[0003] The object of the present invention is to provide a branched fluoroalkyl short-chain quaternary ammonium salt antibacterial agent, which has stronger hydrophobic and oleophobic properties than linear alkyl quaternary ammonium salts, can keep the quaternary ammonium salt fixed in the bacteria to improve and prolong the bactericidal performance, and significantly reduce the biological toxicity.

[0004] The technical solution adopted by the present invention to solve its technical problem is: A branched fluoroalkyl short-chain quaternary ammonium salt antibacterial agent, characterized in that the branched fluoroalkyl short-chain quaternary ammonium salt antibacterial agent is one or a combination of the compounds described in Formula I, Formula II, and Formula III: Wherein, R is -CH3 or -CH2CH3, X is Cl or Br, n is 1 or 2; m is a natural number of 1-4, i is a natural number of 1-4, and h is 1 or 2.

[0005] The present invention forms a branched fluoroalkyl short-chain quaternary ammonium salt by increasing the number of short-chain fluoroalkyl chains. The multiple branches act as umbrellas or masks to shield the hydrophilic groups, which is manifested as an increase in the surface fluorine content and the formation of surface fluorine accumulation, which is beneficial to the improvement of surface performance and stability control ( Figure 1 c).

[0006] Short-chain linear fluorinated groups have relatively low surface energy, and the fluorine surface is unstable and cannot exhibit strong fluorine properties ( Figure 1 b) In order to increase the surface fluorine properties, the conventional method in the prior art is to increase the length of the linear fluoroalkyl chain so that the fluorocarbon group can form fluorine crystals on the surface of the material and better fix the quaternary ammonium salt in the bacteria, thereby improving the fluorine surface performance and prolonging the bactericidal performance ( Figure 1 a) However, increasing the length of the linear fluoroalkyl chain will significantly increase biological toxicity and processing difficulty.

[0007] The inventor has found through research that by increasing the number of fluorine-containing alkyl short chains of a specific length, "umbrella accumulation" can be formed on the material surface, which increases stability and plays a stronger surface fluorine performance. At the same time, the quaternary ammonium salt can be squeezed into the bacterial body to prevent oil pollution to maintain the bactericidal performance of the quaternary ammonium salt. Relative to linear short-chain fluoroalkyl, the problem of poor stability due to the relatively low surface energy of fluorine atoms is overcome. At the same time, relative to long-chain linear fluoroalkyl, fluorine crystals can be formed on the material surface, thereby forming a stable fluorine-containing surface difference. The multi-branched fluoroalkyl of the present invention plays the same or even better surface fluorine performance and antibacterial performance while significantly reducing biological toxicity by increasing the umbrella-shaped accumulation of surface fluorine atoms.

[0008] The present invention increases the amount of fluorine in the compound by increasing the number of fluorocarbon side chains without increasing the length of the fluorocarbon chain, and easily forms fluorine accumulation on the material surface, thereby enhancing the fluorine performance of the material surface of the compound; more fluorine accumulation can squeeze the quaternary ammonium salt into the bacterial body, preventing oil pollution to maintain the bactericidal performance of the quaternary ammonium salt. The present invention increases the number of fluorocarbon side chains, improves the surface fluorine density and improves the regularity of the surface fluorocarbon chain, thereby improving the fluorine performance and stability of the surface of the invention, and at the same time, the surface fluoroalkyl increases, forcing the quaternary ammonium salt to stay in the bacterial body, thereby achieving a better antibacterial effect.

[0009] The preparation method of the compound described in formula I is: quaternization reaction of haloalkyltrialkoxysilane with fluoroalkyl tertiary amine to obtain branched fluoroalkyl quaternary ammonium salt antibacterial agent, the process flow is as follows:

[0010] The fluoroalkyl tertiary amine is selected from one of perfluorotriethylamine, perfluorotripropylamine, perfluorotributylamine, perfluorotripentylamine and perfluorotrihexylamine.

[0011] The preparation method of the compound described in formula II is: a fluoroalkyl primary amine is reacted with a fluorinated alkyl acrylate to synthesize a branched fluoroalkyl tertiary amine, and the branched fluoroalkyl tertiary amine is then reacted with a haloalkyl trialkoxysilane to obtain the compound. The process flow is as follows:

[0012] The fluorine-containing alkyl acrylate is selected from one of perfluoromethylethyl acrylate, perfluoroethylethyl acrylate, perfluoropropylethyl acrylate, perfluorobutylethyl acrylate, perfluoropentylethyl acrylate and perfluorohexylethyl acrylate.

[0013] The preparation method of the compound of formula III is: a fluoroalkyl primary amine is reacted with a fluorinated alkyl epoxy compound to synthesize a branched fluoroalkyl tertiary amine, and the branched fluoroalkyl tertiary amine is then reacted with a haloalkyl trialkoxysilane to synthesize a branched fluoroalkyl short-chain quaternary ammonium salt antibacterial agent of formula III; the process flow is as follows:

[0014] The fluorine-containing alkyl epoxy compound is selected from one of 2,2,3,3,3-pentafluoropropyl oxirane, 2,2,3,3,4,4,4-heptafluorobutyl oxirane, 2,2,3,3,4,4,5,5,5-nonafluoropentyl oxirane, 2,2,3,3,4,4,5,5,6,6,6-undecafluorohexyl oxirane and 2,2,3,3,4,4,5,5,6,6,7,7,7-tridecafluoroheptyl oxirane.

[0015] The fluoroalkyl primary amine is selected from one of 2,2,3,3,3-pentafluoropropylamine, 2,2,3,3,4,4,4-heptafluorobutylamine, and 2,2,3,3,4,4,5,5,5,-nonafluorohexylamine.

[0016] The haloalkyltrialkoxysilane is selected from one of chloromethyltrimethoxysilane, chloroethyltrimethoxysilane, chloropropyltrimethoxysilane, chloromethyltriethoxysilane, chloroethyltriethoxysilane, chloropropyltriethoxysilane, bromomethyltrimethoxysilane, bromoethyltrimethoxysilane, bromopropyltrimethoxysilane, bromomethyltriethoxysilane, bromoethyltriethoxysilane, bromopropyltriethoxysilane, iodomethyltrimethoxysilane, iodoethyltrimethoxysilane, iodopropyltrimethoxysilane, iodomethyltriethoxysilane, iodoethyltriethoxysilane and iodopropyltriethoxysilane.

[0017] The beneficial effects of the present invention are as follows: the antibacterial agent of the present invention has a siloxane group at one end, which can react with a material surface group to improve the adhesion and friction resistance of the branched fluoroalkyl quaternary ammonium salt on the material surface; the other end is a branched fluoroalkyl short chain, which can fix the quaternary ammonium salt in the bacteria to improve the bactericidal effect, and the branched fluoroalkyl side chain improves the hydrophobic and oleophobic properties of the material surface, prevents oil pollution, and maintains the bactericidal performance of the quaternary ammonium salt. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the arrangement of fluoroalkyl compounds with different structures on the interface; Figure 2 This is the antibacterial test chart of the blank control, with an inhibition rate of 9.48%; Figure 3 This is the antibacterial test diagram of comparative example 1, with an antibacterial rate of 95.3%; Figure 4 This is the antibacterial test diagram of comparative example 2, with an antibacterial rate of 44.8%; Figure 5 This is the antibacterial test diagram of Example 1, with an antibacterial rate of 99.5%; Figure 6 This is the antibacterial test diagram of Example 2, with an antibacterial rate of 98.6%; Figure 7 This is the antibacterial test diagram of Example 3, with an antibacterial rate of 97.7%; Figure 8 This is the contact angle test diagram of comparative example 1, the left side is the water contact angle, and the right side is the oil contact angle; Fig. 9 This is the contact angle test diagram of comparative example 2, the left side is the water contact angle, and the right side is the oil contact angle; Fig.10 This is a contact angle test diagram of Example 1, with the left side showing the water contact angle and the right side showing the oil contact angle; Fig.11 This is a contact angle test diagram of Example 2, with the left side showing the water contact angle and the right side showing the oil contact angle; Fig.12 This is a contact angle test diagram of Example 3, with the left side being the water contact angle and the right side being the oil contact angle. DETAILED DESCRIPTION

[0019] The technical solution of the present invention is further described in detail below through specific embodiments.

[0020] In the present invention, unless otherwise specified, the raw materials and equipment used can be purchased from the market or are commonly used in the art. The methods in the following embodiments, unless otherwise specified, are all conventional methods in the art.

[0021] Comparative Example 1: Linear long-chain fluorinated alkyl quaternary ammonium salt Synthesis of N,-trimethoxysilylpropyl-N,N-dimethylheptadecafluoroquinoline quaternary ammonium bromide, the synthesis steps are as follows: (1) N,N-dimethyl-heptadecafluoro-decyl tertiary amine Add 16.50g of 33% dimethylamine aqueous solution and 4g of sodium hydroxide to a three-necked flask equipped with a magnetic stirrer and a thermometer, heat to 70°C, add 20.85g of heptadecafluoroquinoline bromide dropwise, and continue to react for 24h after the addition is complete. After the reaction is completed, add 100mL of ethyl acetate to extract 3 times, combine the extracts, and wash with 100mL of water 3 times. Add 10g of anhydrous sodium sulfate to the oil phase and dry it for 24h, then filter out the desiccant sodium sulfate, and remove the extractant by vacuum rotary evaporation to obtain 7.60g of a light yellow transparent product.

[0022] (2) Quaternization In a three-necked flask equipped with a magnetic stirrer and a thermometer, 6.80 g of N,N-dimethyl-heptadecafluoroquinoline tertiary amine and 15 ml of acetonitrile were added, heated to 85°C, and 8.20 g of bromopropyltrimethoxysilane was added dropwise. After the addition, the reaction was continued for 24 hours. After the reaction was completed, the solvent was evaporated under reduced pressure to obtain 6.50 g of a yellow product.

[0023] Comparative Example 2: Branched fluoroalkyl ultra-short chain quaternary ammonium salt Preparation of N-trimethoxyethyl-N,N-triperfluoroethyl quaternary ammonium bromide, the synthesis steps are as follows: Perfluorotriethylamine (17g, 0.05mol), add 100ml acetonitrile, add bromoethyltrimethoxysilane (20g, 0.1ml), and react for 6-8 hours at 85°C. The mixture is directly distilled under reduced pressure to remove the solvent acetonitrile to obtain the product N-trimethoxyethyl-N,N-triperfluoroethyl quaternary ammonium bromide.

[0024] Example 1 A branched fluoroalkyl short-chain quaternary ammonium salt antibacterial agent having the following structure: R is -CH3 or -CH2CH3; X is Cl or Br; n is 1 or 2; m is 2, 3 or 4.

[0025] Preparation of N-trimethoxyethyl-N,N,N-triperfluorohexyl quaternary ammonium bromide, the synthesis steps are as follows: Perfluorotrihexylamine (25g, 0.05mol), add 100ml acetonitrile, add bromoethyltrimethoxysilane (20g, 0.1ml), and react for 6-8 hours at 85°C. The mixture is directly distilled under reduced pressure to remove the solvent acetonitrile to obtain the product N-trimethoxyethyl-N,N,N-triperfluorohexyl quaternary ammonium bromide.

[0026] Other branched fluoroalkyl short-chain quaternary ammonium salt antibacterial agents can be synthesized using the method of this embodiment as follows: Serial number Haloalkylalkoxysilane Fluoroalkyl tertiary amine Product Name 1 Bromoethyltrimethoxysilane Perfluorotributylamine N-Trimethoxyethyl-N,N,N-triperfluorohexyl ammonium bromide 2 Bromoethyltrimethoxysilane Perfluorotripropylamine N-Trimethoxyethyl-N,N,N-triperfluorohexyl ammonium bromide 3 Bromoethyltrimethoxysilane Perfluorotripentylamine N-Trimethoxyethyl-N,N,N-triperfluorohexyl ammonium bromide 4 Chloromethyltrimethoxysilane Perfluorotributylamine N-Trimethoxymethyl-N,N,N-triperfluorohexyl quaternary ammonium chloride 5 Chloromethyltrimethoxysilane Perfluorotripropylamine N-Trimethoxymethyl-N,N,N-triperfluorohexyl quaternary ammonium chloride 6 Chloromethyltrimethoxysilane Perfluorotripentylamine N-Trimethoxymethyl-N,N,N-triperfluorohexyl quaternary ammonium chloride .

[0027] Example 2 A branched short-chain fluorinated alkyl quaternary ammonium salt antibacterial agent having the following structure: R is -CH3 or -CH2CH3; X is Cl or Br; n and h are both 1 or 2; m and i are both 2, 3 or 4.

[0028] Preparation of N-trimethoxyethyl-N-2,2,3,3,4,4,4-heptafluorobutyl-N,N-di-acetic acid-(2-perfluoropentylethyl) ester quaternary ammonium bromide, the synthesis steps are as follows: (1) Synthesize N-2,2,3,3,4,4,4-heptafluorobutyl-N,N-di-acetic acid-(2-perfluoropentylethyl) ester 2,2,3,3,4,4,4-heptafluorobutylamine (2.0 g, 10 mmol), add it into 10 ml of trifluorotoluene, add perfluoropentylethyl acrylate (8.4 g, 20 mmol), react at 25° C. for 6 hours, directly distill the mixture under reduced pressure to remove the solvent trifluorotoluene, and obtain N-2,2,3,3,4,4,4-heptafluorobutyl-N,N-di-2-perfluoropentylethyl acetate.

[0029] (2) Synthesis of N-trimethoxyethyl-N-2,2,3,3,4,4,4-heptafluorobutyl-N,N-di-acetic acid-(2-perfluoropentylethyl) ester quaternary ammonium bromide N-2,2,3,3,4,4,4-heptafluorobutyl-N,N-di-acetic acid-(2-perfluoropentylethyl) ester (2.0 g, 3.3 mmol), 10 ml of acetonitrile, bromoethyltrimethoxysilane (1.6 g, 8.0 mml), the reaction was continued for 6-8 hours at a temperature of 85°C. The mixture was directly distilled under reduced pressure to remove the solvent acetonitrile to obtain the product N-trimethoxyethyl-N-2,2,3,3,4,4,4-heptafluorobutyl-N,N-di-acetic acid-(2-perfluoropentylethyl) ester quaternary ammonium bromide.

[0030] The intermediate (1) can be synthesized by the method of this example as follows:

[0031] The method of this embodiment can be used to synthesize a branched fluoroalkyl short-chain quaternary ammonium salt antibacterial agent as follows:

[0032] Example 3 A branched short-chain fluorinated alkyl quaternary ammonium salt antibacterial agent having the following structure: R is -CH3 or -CH2CH3; X is Cl or Br; n and h are both 1 or 2; m and i are both 2, 3 or 4.

[0033] Preparation of N-trimethoxyethyl-N-2,2,3,3,4,4,4-heptafluorobutyl-N,N-di-2-perfluoropentyl isopropanol quaternary ammonium bromide, the synthesis steps are as follows: (1) Synthesis of N-2,2,3,3,4,4,4-heptafluorobutyl-N,N-di-2-perfluoropentyl isopropanol 2,2,3,3,4,4,4-heptafluorobutylamine (2.0 g, 10 mmol) was added to 10 ml of trifluorotoluene, and 3-(perfluoro-n-pentyl)propylene oxide (7.6 g, 20 mmol) was added. The mixture was reacted at 25°C for 6 hours. The mixture was directly distilled under reduced pressure to remove the solvent trifluorotoluene to obtain N-2,2,3,3,4,4,4-heptafluorobutyl-N,N-di-2-perfluoropentyl isopropanol.

[0034] (2) Synthesis of N-trimethoxyethyl-N-2,2,3,3,4,4,4-heptafluorobutyl-N,N-di-2-perfluoropentyl isopropanol quaternary ammonium bromide N-2,2,3,3,4,4,4-heptafluorobutyl-N,N-di-2-perfluoropentyl isopropanol (2.0 g, 5 mmol), 10 ml of acetonitrile, bromoethyl trimethoxysilane (2 g, 10 mml) were added, and the reaction lasted for 6-8 hours at 85°C. The mixture was directly distilled under reduced pressure to remove the solvent acetonitrile to obtain the product N-trimethoxyethyl-N-2,2,3,3,4,4,4-heptafluorobutyl-N,N-di-2-perfluoropentyl isopropanol quaternary ammonium bromide.

[0035] The intermediate (1) can be synthesized by the method of this example as follows:

[0036] The method of this embodiment can be used to synthesize a branched fluoroalkyl short-chain quaternary ammonium salt antibacterial agent as follows:

[0037] Antimicrobial testing Take 0.4ml-0.5ml of the experimental bacterial solution and add it dropwise to the blank control sample, the antibacterial agent sample of comparative example 1, the antibacterial agent sample of comparative example 2, and the branched fluoroalkyl short-chain quaternary ammonium salt antibacterial agent sample of examples 1-3.

[0038] Use fire-extinguishing tweezers to pick up the sterilization cover film and place it on the surface of the sample. Make sure it is flat and free of bubbles, so that the bacteria can evenly contact the sample. Place it in a sterilized plate and culture it at (37±1)℃ and relative humidity RH>9 for 24 hours. Perform 3 parallel experiments for each sample.

[0039] Take out the samples cultured for 24 hours, add 20 ml of washing solution respectively, wash the sample plate and covering film repeatedly, shake well, take the washing solution and inoculate it into nutrient agar medium, culture at (37±1)℃ for (24-48) hours, and count the viable bacteria. Determine the number of viable bacteria in the washing solution according to the method of GB / T 4789.2.

[0040] Test result calculation The viable count measured above is multiplied by 1000 to obtain the actual viable count after 24 hours of sample culture. The three parallel viable counts of the same blank control must meet the requirement of (highest logarithm value - lowest logarithm value) / average viable count logarithm value less than or equal to 0.3.

[0041] The calculation formula of antibacterial rate is: R=(AC) / A×100 In the formula: Antibacterial rate, expressed as (%), the figures are valid values, according to the provisions of GB / T 1250; A- Average number of recovered bacteria after 24 hours in the blank control sample (cfu / piece) C- Average number of recovered bacteria (cfu / plate) after 24 hours of antibacterial sample.

[0042] Contact angle test 1○ Wash the slide (76mm*26mm*2mm) with alkaline water and deionized water for later use; 2○ Prepare -N,-trimethoxysilylpropyl-N,N-dimethylheptadecafluoroquinazone bromide DMF solution, solid content is 10%; prepare N-trimethoxyethyl-N,N-triperfluoroethyl quaternary ammonium bromide DMF solution, solid content is 10%; prepare N-trimethoxyethyl-N,N,N-triperfluorohexyl quaternary ammonium bromide DMF solution, solid content is 10%; prepare N-trimethoxyethyl-N-2,2,3,3,4,4,4-heptafluorobutyl-N,N-di-acetic acid-(2-perfluoropentylethyl) ester quaternary ammonium bromide DMF solution, solid content is 10%; prepare N-trimethoxyethyl-N-2,2,3,3,4,4,4-heptafluorobutyl-N,N-di-acetic acid-(2-perfluoropentylethyl) ester quaternary ammonium bromide DMF solution, solid content is 10% 3○ Drop several solutions onto the glass slide respectively, cover it with water, dry it at 50℃, and then measure the water contact angle with a contact angle meter.

[0043] The branched fluoroalkyl quaternary ammonium salt antibacterial agent prepared in the above example and the comparative example were tested under the same conditions, and the results were as follows: Product Name Contact angle (water)° Contact angle (oil)° Antibacterial rate (%) Comparative Example 1 145.9 87.2 95.3 Comparative Example 2 104.4 82.2 44.8 Example 1 145.5 95.4 99.5 Example 2 142.3 94.2 98.6 Example 3 141.9 82 97.7 .

[0044] Compared with the antibacterial rate, the branched fluoroalkyl quaternary ammonium salt antibacterial agent of the present invention has a stronger bactericidal effect than the long-chain linear fluoroalkyl quaternary ammonium salt antibacterial agent of Comparative Example 1; it can be seen from Comparative Example 2 that if the side chain is too short, even if there are multiple branches, it is impossible to form a specific fluorine accumulation to effectively improve the antibacterial and hydrophobic and oleophobic properties; compared with Comparative Example 1, the hydrophobic and oleophobic properties of the branched fluoroalkyl quaternary ammonium salt of the present invention are close to or even exceed those of Comparative Example 1.

[0045] The above-described embodiment is only a preferred solution of the present invention and does not limit the present invention in any form. There are other variations and modifications without exceeding the technical solution described in the claims.

Claims

1. A branched fluoroalkyl short-chain quaternary ammonium salt antibacterial agent, characterized in that: The branched fluoroalkyl short-chain quaternary ammonium salt antibacterial agent is one or a combination of the compounds of formula I, formula II, and formula III: Wherein, R is -CH3 or -CH2CH3, X is Cl or Br, n is 1 or 2; m is a natural number of 1-4, i is a natural number of 1-4, and h is 1 or 2.

2. The branched fluoroalkyl short-chain quaternary ammonium salt antibacterial agent according to claim 1, characterized in that: The preparation method of the compound of formula I is: quaternization reaction of haloalkyltrialkoxysilane with fluoroalkyl tertiary amine to obtain a branched fluoroalkyl quaternary ammonium salt antibacterial agent of formula I, and the process flow is as follows:

3. The branched fluoroalkyl short-chain quaternary ammonium salt antibacterial agent according to claim 2, characterized in that: The fluoroalkyl tertiary amine is selected from one of perfluorotriethylamine, perfluorotripropylamine, perfluorotributylamine, perfluorotripentylamine and perfluorotrihexylamine.

4. The branched fluoroalkyl short-chain quaternary ammonium salt antibacterial agent according to claim 1, characterized in that: The preparation method of the compound of formula II is: a fluoroalkyl primary amine is reacted with a fluorinated alkyl acrylate to synthesize a branched fluoroalkyl tertiary amine, and the branched fluoroalkyl tertiary amine is reacted with a haloalkyl trialkoxysilane to synthesize a branched fluoroalkyl quaternary ammonium salt antibacterial agent of formula II. The process flow is as follows:

5. The branched fluoroalkyl short-chain quaternary ammonium salt antibacterial agent according to claim 4, characterized in that: The fluorine-containing alkyl acrylate is selected from one of perfluoromethylethyl acrylate, perfluoroethylethyl acrylate, perfluoropropylethyl acrylate, perfluorobutylethyl acrylate, perfluoropentylethyl acrylate and perfluorohexylethyl acrylate.

6. The branched fluoroalkyl short-chain quaternary ammonium salt antibacterial agent according to claim 1, characterized in that: The preparation method of the compound of formula III is: a fluoroalkyl primary amine is reacted with a fluorinated alkyl epoxy compound to synthesize a branched fluoroalkyl tertiary amine, and the branched fluoroalkyl tertiary amine is then reacted with a haloalkyl trialkoxysilane to synthesize a branched fluoroalkyl short-chain quaternary ammonium salt antibacterial agent of formula III; the process flow is as follows:

7. The branched fluoroalkyl short-chain quaternary ammonium salt antibacterial agent according to claim 6, characterized in that: The fluorine-containing alkyl epoxy compound is selected from one of 2,2,3,3,3-pentafluoropropyl oxirane, 2,2,3,3,4,4,4-heptafluorobutyl oxirane, 2,2,3,3,4,4,5,5,5-nonafluoropentyl oxirane, 2,2,3,3,4,4,5,5,6,6,6-undecafluorohexyl oxirane and 2,2,3,3,4,4,5,5,6,6,7,7,7-tridecafluoroheptyl oxirane.

8. The branched fluoroalkyl short-chain quaternary ammonium salt antibacterial agent according to claim 4 or 6, characterized in that: The fluoroalkyl primary amine is selected from one of 2,2,3,3,3-pentafluoropropylamine, 2,2,3,3,4,4,4-heptafluorobutylamine, and 2,2,3,3,4,4,5,5,5,-nonafluorohexylamine.

9. The branched fluoroalkyl short-chain quaternary ammonium salt antibacterial agent according to claim 2, 4 or 6, characterized in that: The haloalkyltrialkoxysilane is selected from one of chloromethyltrimethoxysilane, chloroethyltrimethoxysilane, chloropropyltrimethoxysilane, chloromethyltriethoxysilane, chloroethyltriethoxysilane, chloropropyltriethoxysilane, bromomethyltrimethoxysilane, bromoethyltrimethoxysilane, bromopropyltrimethoxysilane, bromomethyltriethoxysilane, bromoethyltriethoxysilane, bromopropyltriethoxysilane, iodomethyltrimethoxysilane, iodoethyltrimethoxysilane, iodopropyltrimethoxysilane, iodomethyltriethoxysilane, iodoethyltriethoxysilane and iodopropyltriethoxysilane.

Images