Polycation-pi antibacterial agent as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of antibacterial agents, and relates to a polycation-pi antibacterial agent as well as a preparation method and application thereof. The antibacterial agent has a controllable sequence structure, the main chain of the polymer is composed of alternate hydrophobic chain segments and hydrophilic chain segments, guanidine salts are regularly arranged, surface positive charges are intensively distributed, and multiple interactions of cation-pi, hydrogen bonds and pi-pi stacking can be generated among molecules of the antibacterial agent. The preparation method comprises the following steps: in the presence of a catalyst or in the absence of the catalyst, carrying out melt polymerization or solution polymerization on polycation guanidine salt and a compound with a benzene ring in a molar ratio of (0.8-1.2): 1 to obtain the polycation-pi antibacterial agent. According to the application, the antibacterial agent is used for finishing a fabric to obtain an antibacterial fabric, and the fabric is made of hydrophobic fibers. The preparation method of the antibacterial agent is simple, and the antibacterial fabric with durable antibacterial, directional moisture permeable and refrigeration effects can be prepared by adopting the antibacterial agent.

Description

Technical Field

[0001] The invention belongs to the technical field of antimicrobial agents and relates to a polycationic-π antimicrobial agent and a preparation method and application thereof. Background Art

[0002] With the frequent outbreak of epidemics, pathogenic microorganisms in droplets / aerosols pose a serious threat to human health, and existing clothing and other fabrics often lead to the cultivation and spread of bacteria and viruses. In order to cope with this escalating threat, developing appropriate methods to make fabrics antibacterial can reduce cross-infection of diseases and alleviate the economic pressure on families and society, which has broad application prospects.

[0004] Antimicrobial agents are one of the prerequisites for the preparation of antimicrobial fabrics. Commonly used antimicrobial agents include inorganic antimicrobial agents and organic antimicrobial agents. Among inorganic antimicrobial agents, silver nanoparticles, copper nanoparticles and their metal oxides are widely used, which have broad-spectrum and high-efficiency antimicrobial properties. However, one problem exposed by these nanoparticles is that nanoscale metals can cause cytotoxicity and genotoxicity to organisms when immersed in the environment. Chitosan, as a representative of natural antimicrobial agents, tends to be eco-friendly and is abundant on the earth. However, due to the sensitivity of chitosan to the pH value of the finishing liquid and its poor adhesion to the fabric in the absence of a cross-linking agent, its application is limited. Quaternary ammonium compounds, halamine compounds, guanidine salts, triclosan, etc. are widely used as organic antibacterial agents. However, the composition and structural properties of their macromolecular chains determine that their intermolecular interaction forces are limited, and it is difficult to physically adsorb them on fabrics. Therefore, they are generally fixed on fabrics by grafting to obtain washable antibacterial fabrics. In the grafting method, a cross-linking agent with high reaction activity is usually used, and the process is complicated. This is easy to cause a large amount of waste of antibacterial agents, and it will bring about equipment transformation problems and a large amount of energy waste. At the same time, long-term use of quaternary ammonium compounds and triclosan will make bacteria resistant. Halamine compounds and triclosan have high antibacterial efficacy, but they are highly toxic, have irritating odors, and have negative effects on the human body.

[0005] The improvement of the prior art on guanidine salt antibacterial agents containing aromatic rings is mainly reflected in the formation of small molecule compounds by functionalized terminal groups. For example, patent CN104230760B proposes a method for preparing N-aryl-substituted biguanidine hydrobromide compounds, which is to covalently connect benzene rings at both ends of biguanidine salts to form small molecule compounds. However, this small molecule compound has poor antibacterial effect and low fastness for fabric finishing. Patent application CN105566547A proposes a method for preparing guanidine polymer antibacterial agents, which is achieved by copolymerizing maleic anhydride functionalized with styrene. The patent with application number CN202410769129.2 proposes a method for preparing antibacterial and deodorizing particles using polyhexamethylene guanidine salt as a base material and grafting with halogenated hydrocarbons with benzene rings. However, the position of their aromatic rings is on the polymer side chain, the antibacterial effect is limited, and the preparation process is complicated. The antibacterial properties of guanidine salt antibacterial agents containing aromatic rings need to be further improved. At the same time, the antibacterial fabrics made with this type of antibacterial agent have poor water washing resistance and friction resistance. Summary of the invention

[0006] The purpose of the present invention is to solve the problems in the prior art and to provide a polycationic antibacterial agent and a preparation method and application thereof.

[0007] In order to achieve the above object, the present invention adopts the following technical scheme:

[0008] A polycationic antibacterial agent having a structural formula of one of the following formulas A to F:

[0009]

[0010] Where n 1 、n 2 and n 4 The value range is 1-10, n 3 and n 5 The value range is 2-50, X - Cl - ,PO 4 3- 、NO 3 - , CO 3 2- or C 6 H 5 SO 3 - , -M is -OH, -COOCH 3 or -Cl.

[0011] As the preferred technical solution:

[0012] The polycationic-π antibacterial agent as described above has a number average molecular weight of 500-20000 Da, a minimum inhibitory concentration of 1-128 μg / mL, and a minimum bactericidal concentration of 1-256 μg / mL.

[0013] The present invention also provides a method for preparing a polycation-π antibacterial agent as described in any one of the above items, wherein a polycation guanidine salt and a compound having a benzene ring in a molar ratio of 0.8-1.2:1 are subjected to melt polymerization or solution polymerization in the presence of a catalyst or in the absence of a catalyst to obtain the polycation-π antibacterial agent;

[0014] The structural formula of the cationic guanidine salt is one of the following formulas i to iv:

[0015]

[0016] The compound with a benzene ring is one of the following formulas Ⅰ to Ⅳ:

[0017]

[0018] As the preferred technical solution:

[0019] In the method described above, the process of melt polymerization is: first, the temperature is raised to 100-160°C under stirring, and the reaction is carried out for 2-12 hours, then the temperature is raised to 150-260°C, and the reaction is carried out for 1-5 hours, and finally, the vacuum is evacuated to a vacuum degree of ≤200Pa, and the reaction is carried out for 0-10 hours (the reaction time is 0, that is, no vacuum is evacuated, and this operation is omitted).

[0020] In the method described above, the molar ratio of the cationic guanidine salt to the compound having a benzene ring is 0.8-1.2:1.

[0021] In the method described above, the solvent used for solution polymerization is one or more of dimethyl sulfoxide, N,N-dimethylformamide, water, isopropanol, methanol, ethanol and acetone; the temperature of solution polymerization is 0-130° C., and the time is 0.5-20 hours.

[0022] The method as described above, wherein the catalyst is an acidic catalyst (HCl or H 2 SO 4 ), alkaline catalyst (NaOH) or metal catalyst (aluminum or copper based), the amount of catalyst added is 0.01-0.5% of the total mass of the polycationic guanidine salt and the compound with a benzene ring.

[0023] The present invention also provides an antibacterial fabric, which is formed by finishing the fabric with an antibacterial agent (the finishing method may be impregnation, spraying, etc.), the fabric is made of hydrophobic fibers, the antibacterial agent is one or more of compounds A to F, and the structural formula of compounds A to F corresponds to the following formulas A to F:

[0024]

[0025] Where n 1 、n 2 and n 4 The value range is 1-10, n 3 and n 5 The value range is 2-50, X - Cl - ,PO 4 3- 、NO 3 - , CO 3 2- or C 6 H 5 SO 3 - , -M is -OH, -COOCH 3 or -Cl.

[0026] As the preferred technical solution:

[0027] In the antibacterial fabric as described above, the mass of the antibacterial agent is 1-5% of the mass of the fabric.

[0028] The antibacterial fabric as described above is a polyethylene terephthalate fabric, a polytrimethylene terephthalate fabric, a polybutylene terephthalate fabric, a polybutylene terephthalate-adipate fabric, a polylactic acid fabric, a polyethylene fabric, a polypropylene fabric, a polyterephthalamide fabric, a polyisophthalamide fabric, a heterocyclic polybenzimidazole fabric or a poly(p-phenylene benzobisoxazole) fabric.

[0029] An antibacterial fabric as described above is finished by spraying, and the antibacterial agent is only finished on one side of the fabric; the water evaporation rate of the antibacterial fabric is greater than 0.6g / h; the temperature of the antibacterial fabric after being placed on the skin surface sprayed with water for 1 minute is at least 2°C lower than the temperature of the fabric before finishing after being placed on the skin surface sprayed with water for 1 minute.

[0030] After spraying the antibacterial agent on one side of the fabric, the sprayed surface showed good wetting ability and smaller pores, while the unsprayed surface maintained poor hydrophilicity. In view of the difference in wettability and pore size between the two sides of the fabric, the resulting antibacterial fabric showed unilateral moisture conduction ability, and after wearing the antibacterial fabric, a dry and cool microenvironment could be formed between the antibacterial fabric and the human body.

[0031] Because antibacterial fabrics have unidirectional moisture conduction capabilities and the hydrophobic segments in the antibacterial agent can quickly dissipate moisture into space, when the human body sweats, the fabric can quickly absorb moisture from the skin surface and transfer it from the inside of the fabric to the outside of the fabric. The evaporation of moisture on the outside of the fabric takes away the body's heat, thereby lowering the skin surface temperature. Therefore, antibacterial fabrics have a good cooling effect.

[0032] The antibacterial fabric as described above has an antibacterial rate of ≥97% against Escherichia coli, Staphylococcus aureus and Candida albicans; after being washed 50 times, the antibacterial rate of the antibacterial fabric against Escherichia coli, Staphylococcus aureus and Candida albicans is ≥90%; after 100 friction resistance tests, the antibacterial rate of the antibacterial fabric against Escherichia coli, Staphylococcus aureus and Candida albicans is ≥90%.

[0033] Principle of the invention:

[0034] Under the premise that both "guanidine salt" and "aromatic ring" are contained in the structural formula, the antibacterial performance of the antibacterial agent of the present invention is better than that of the antibacterial agent of the prior art, mainly because: the antibacterial agent of the present invention has a controllable sequence structure, and the polymer main chain is composed of alternating hydrophobic segments and hydrophilic segments, which helps to form a relatively rigid one-dimensional structure of macromolecules with a certain molecular weight, which is of great help to the antibacterial effect of the antibacterial agent. In addition, the guanidine salts are arranged regularly and the surface positive charges are concentratedly distributed, which is also of great help to the antibacterial effect of the antibacterial agent. The molecular chain length of the antibacterial agent of the prior art is relatively short, and it is a small molecule compound. It is difficult to penetrate the bacterial cell membrane and kill bacteria when acting with bacteria, or it is difficult for the guanidine salts to form an effective positive charge concentration distribution at the side group position of the macromolecular chain of the polymer, so the antibacterial effect of the antibacterial agent of the prior art is relatively poor.

[0035] In addition, under the premise that both "guanidine salt" and "aromatic ring" are contained in the structural formula, the antibacterial fabric prepared by using the antibacterial agent of the present invention has better water washing resistance and friction resistance, mainly for the following reasons:

[0036] (1) In terms of the interaction between the molecular chains of the antimicrobial agent, the molecules of the antimicrobial agent of the present invention can generate multiple interactions such as cation-π, hydrogen bonding and π-π stacking. Figure 1 As shown, it causes strong self-cohesion, which helps to form a stable antibacterial adhesive (resistant to washing and friction) on the fabric surface.

[0037] (2) The antibacterial agent of the present invention can generate multiple interactions of cation-π, hydrogen bonding and π-π stacking with the fabric, thereby stably adhering to the surface of the fabric. Now, take the antibacterial agent as PXDAG (structural formula corresponding to Formula A) and the fabric as polyethylene terephthalate (PET) fabric as an example for explanation. In order to determine whether cation-π and hydrogen bonding interactions can promote strong interfacial adhesion between PXDAG and PET, we first performed density functional theory (DFT) simulations to demonstrate the intrinsic stability of the PXDAG and PET system. The possible structures and electrostatic potential distributions of PET, PXDAG and PET / PXDAG were optimized by DFT ( Figure 2 (a)). When PET / PXDAG is close to each other, the intermolecular interaction energy is lower than the interaction energy of two single molecules due to the cation-π interaction between the nitrogen cations and benzene rings of the adjacent molecules. The Gibbs free energy change (ΔG) of the formation of the PET / PXDAG composite is -8.2 kcal / mol. In order to effectively demonstrate the non-covalent interaction, the molecular density based Hirshfeld partition (IGMH) analysis was further used to find that there are cation-π interactions and hydrogen bonds in PET / PXDAG, as shown in the figure. Figure 2 As shown in (b).

[0038] Two-dimensional NMR spectroscopy further identified interfacial interactions including hydrogen bond networks and cation-π. As shown in Figure 3, when 2M BHET (a model compound for PET) and PXDAG (a polycation-π antimicrobial agent) were added to the solution, a weak NOE occurred between the aromatic ring groups and the guanidine groups in BHET. These data further demonstrate the existence of non-covalent interactions between benzene and guanidine, again indicating that cation-π and hydrogen bond interactions may also exist in PET and PXDAG. The cation-π interactions and hydrogen bonds in PXDAG-PET will cause the material to exhibit strong non-covalent cohesion, dissipate more fracture energy, and significantly increase the interfacial fracture threshold.

[0039] Beneficial Effects

[0040] The preparation method of the polycationic-π antibacterial agent of the present invention is simple, especially melt polymerization, which can introduce aromatic rings with controllable sequence into guanidine polymers in only one step of reaction.

[0041] The polycationic-π antibacterial agent of the present invention introduces aromatic rings to increase multiple interactions with fabrics, and can improve water washing fastness only through simple adsorption without adding crosslinking agents, fastness agents, etc.

[0042] The repellent fabric of the present invention can effectively inhibit bacteria, has a long-lasting effect, and has a significant washing resistance effect, which shows the robust interaction between the functional additive and the fabric achieved through chemical sequence structure design.

[0043] The antibacterial fabric developed by the spraying technology in the present invention has a spontaneous perspiration function, the skin temperature is lower than the surrounding environment, and has good softness, appearance and wear resistance.

[0044] The antibacterial fabric of the present invention can quickly absorb moisture from the skin surface and transfer it from the inside of the fabric to the outside of the fabric. Since the evaporation of moisture takes away the heat of the human body, the skin surface temperature can be reduced.

[0045] The raw materials used in the invention are low-cost and the preparation method is simple, and durable antibacterial, directional moisture permeable and refrigeration multifunctional fabrics can be prepared on a large scale, which is conducive to industrial application. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 Schematic diagram of the intermolecular forces of PXDAG (cation-π, hydrogen bond, π-π stacking).

[0047] Figure 2 (a) Structure and electrostatic potential distribution of PET, PXDAG and PET / PXDAG;

[0048] Figure 2 (b) Analysis of the interaction of IGMH in the PET / PXDAG system;

[0049] Figure 3 (a) is a schematic diagram of the cation-π interaction between PET and PXDAG;

[0050] Figure 3(b) is the 1H-1H NOESY spectrum of the mixture of BHET and PXDAG;

[0051] Figure 3(c) is the amplified signal of the coupling of Ha-He and Hb-He;

[0052] Figure 4 The polycation-π antimicrobial agent of Example 1 1 H-NMR spectrum;

[0053] Figure 5 is the MALDI-TOF-MS spectrum of the polycation-π antibacterial agent of Example 1;

[0054] Figure 6 From left to right, the MBC results of PXDAG aqueous solution with concentrations of 64 μg / mL, 32 μg / mL, and 16 μg / mL against Staphylococcus aureus;

[0055] Figure 7 From left to right, the MBC results of PXDAG aqueous solution with concentrations of 256 μg / mL, 128 μg / mL, and 64 μg / mL against E. coli;

[0056] Figure 8 This is the 1H NMR spectrum of the polycationic antibacterial agent of Example 2. DETAILED DESCRIPTION

[0057] The present invention will be further described below in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not intended to limit the scope of the present invention. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms fall within the scope limited by the appended claims of the application equally.

[0058] Detection methods of relevant indicators in the embodiments and comparative examples:

[0059] Minimum inhibitory concentration and minimum bactericidal concentration of antimicrobial agents: tested by micro-dilution method;

[0060] Water evaporation rate: Tested in accordance with GB / T 21655.1-2008 Evaluation of moisture absorption and quick-drying properties of textiles Part 1: Single item combined test method;

[0061] The temperature of the antibacterial fabric after being placed on the skin surface sprayed with water for 1 minute and the temperature of the fabric before finishing after being placed on the skin surface sprayed with water for 1 minute were measured and tested using an infrared thermal imager (FOTRIC 315, USA) and analyzed by AnalyzIR software.

[0062] Antibacterial rate: Tested in accordance with standard GB / T 20944.3-2008 Evaluation of antibacterial properties of textiles Part 3: Oscillation method.

[0063] Washing: Refer to GB / T 20944.3-2008 Evaluation of antibacterial properties of textiles Part 3: Oscillation method.

[0064] Friction resistance test: The test was conducted in accordance with ASTM D4966-22, Standard Test Method for Abrasion Resistance of Textile Fabrics (Martindale Abrasion Tester Method).

[0065] Example 1

[0066] A method for preparing a polycationic antibacterial agent is as follows:

[0067] (1) Raw material preparation:

[0068] Cationic guanidine salts:

[0069] Compounds with benzene rings:

[0070] (2) Preparation of antibacterial agent:

[0071] First, a cationic guanidine salt and a compound with a benzene ring in a molar ratio of 1:1 are mixed, then the temperature is raised to 100°C under stirring, the reaction is carried out for 12 hours, and then the temperature is raised to 190°C, the reaction is carried out for 5 hours, and finally the vacuum is evacuated to a vacuum degree of 200 Pa and the reaction is carried out for 10 hours to obtain a polycationic-π antibacterial agent.

[0072] The final polycation-π antibacterial agent has the structural formula:

[0073]

[0074] Where n 1 =1,n 2 =1,n 3 =50,X - Cl - ;

[0075] The polycation-π antibacterial agent 1 H-NMR spectrum Figure 4 As shown, the MALDI-TOF-MS spectrum is as follows Figure 5 As shown, the number average molecular weight is 10000Da, the minimum inhibitory concentration is 8μg / mL, and the minimum bactericidal concentration is 64μg / mL; the MBC results of 64μg / mL, 32μg / mL, and 16μg / mL concentrations of PXDAG aqueous solution against Staphylococcus aureus are as follows Figure 6 As shown in Figure 2, the MBC results of 256 μg / mL, 128 μg / mL, and 64 μg / mL PXDAG aqueous solutions on Escherichia coli are as follows: Figure 7 shown.

[0076] Example 2

[0077] A method for preparing a polycationic antibacterial agent is as follows:

[0078] (1) Raw material preparation:

[0079] Cationic guanidine salts:

[0080] Compounds with benzene rings:

[0081] (2) Preparation of antibacterial agent:

[0082] First, a cationic guanidine salt and a compound with a benzene ring in a molar ratio of 1.2:1 are mixed, then the temperature is raised to 160°C under stirring, the reaction is carried out for 2 hours, the temperature is then raised to 260°C, the reaction is carried out for 1 hour, and finally the vacuum is evacuated to a vacuum degree of -Pa and the reaction is carried out for -h to obtain a polycationic-π antibacterial agent.

[0083] The final polycation-π antibacterial agent has the structural formula:

[0084]

[0085] Where n 1 =1,n 2 =1,n 3 =50,n 4 =6,X - Cl - ;

[0086] The polycation-π antibacterial agent 1 H-NMR spectrum Figure 8 As shown, the number average molecular weight is 18800Da, the minimum inhibitory concentration is 1μg / mL, and the minimum bactericidal concentration is 1μg / mL.

[0087] Example 3

[0088] A method for preparing a polycationic antibacterial agent is as follows:

[0089] (1) Raw material preparation:

[0090] Cationic guanidine salts:

[0091] Compounds with benzene rings:

[0092] Catalyst: HCl;

[0093] (2) Preparation of antibacterial agent:

[0094] First, a cationic guanidine salt, a compound with a benzene ring and a catalyst in a molar ratio of 0.9:1 are mixed, then heated to 110°C under stirring, reacted for 2 hours, then heated to 190°C, reacted for 2 hours, and finally evacuated to a vacuum degree of 200 Pa and reacted for 1 hour to obtain a polycationic-π antibacterial agent;

[0095] The added amount of the catalyst is 0.01% of the total mass of the polycationic guanidine salt and the compound with a benzene ring.

[0096] The final polycation-π antibacterial agent has the structural formula:

[0097]

[0098] Where n 1 =1,n 2 =1,n 3 =20,X - Cl - ;

[0099] The number average molecular weight of the polycationic-π antibacterial agent is 5000Da, the minimum inhibitory concentration is 4μg / mL, and the minimum bactericidal concentration is 4μg / mL.

[0100] Example 4

[0101] A method for preparing a polycationic antibacterial agent is as follows:

[0102] (1) Raw material preparation:

[0103] Cationic guanidine salts:

[0104] Compounds with benzene rings:

[0105] Catalyst: copper oxide;

[0106] (2) Preparation of antibacterial agent:

[0107] First, a cationic guanidine salt, a compound with a benzene ring and a catalyst in a molar ratio of 0.8:1 are mixed, then the temperature is raised to 130°C under stirring, the reaction is carried out for 2 hours, then the temperature is raised to 180°C, the reaction is carried out for 5 hours, and finally the vacuum is evacuated to a vacuum degree of -Pa, and the reaction is carried out for -h to obtain a polycationic-π antibacterial agent;

[0108] The added amount of the catalyst is 0.5% of the total mass of the polycationic guanidine salt and the compound with a benzene ring.

[0109] The final polycation-π antibacterial agent has the structural formula:

[0110]

[0111] Where n 1 =1,n 2 =1,n 3 =4,n 4 =6,X - C 6 H 5 SO 3 - ;

[0112] The number average molecular weight of the polycation-π antibacterial agent is 3000Da, the minimum inhibitory concentration is 8μg / mL, and the minimum bactericidal concentration is 8μg / mL.

[0113] Example 5

[0114] A method for preparing a polycationic antibacterial agent is as follows:

[0115] (1) Raw material preparation:

[0116] Cationic guanidine salts:

[0117] Compounds with benzene rings:

[0118] Catalyst: NaOH;

[0119] (2) Preparation of antibacterial agent:

[0120] The polycationic-π antimicrobial agent was prepared by solution polymerization from cationic guanidine salt and a compound with a benzene ring in a molar ratio of 0.9:1. The solvent used was isopropanol. The solution polymerization temperature was 0°C and the time was 0.5h.

[0121] The added amount of the catalyst is 0.5% of the total mass of the polycationic guanidine salt and the compound with a benzene ring.

[0122] The final polycation-π antibacterial agent has the structural formula:

[0123]

[0124] Where n 5 =5, -M is -Cl, X - C 6 H 5 SO 3 - ;

[0125] The number average molecular weight of the polycationic-π antibacterial agent is 2000Da, the minimum inhibitory concentration is 128μg / mL, and the minimum bactericidal concentration is 256μg / mL.

[0126] Example 6

[0127] A method for preparing a polycationic antibacterial agent is as follows:

[0128] (1) Raw material preparation:

[0129] Cationic guanidine salts:

[0130] Compounds with benzene rings:

[0131] (2) Preparation of antibacterial agent:

[0132] The polycationic-π antibacterial agent was prepared by solution polymerization from cationic guanidine salt and a compound with a benzene ring in a molar ratio of 0.8:1. The solvent used was water. The solution polymerization temperature was 90°C and the time was 20 hours.

[0133] The final polycation-π antibacterial agent has the structural formula:

[0134]

[0135] Where n 4 =6,n 5 =13, -M is -COOCH 3 , X - Cl - ;

[0136] The number average molecular weight of the polycationic-π antibacterial agent is 5500Da, the minimum inhibitory concentration is 8μg / mL, and the minimum bactericidal concentration is 16μg / mL.

[0137] Example 7

[0138] A method for preparing an antibacterial fabric, specifically comprising: spraying an antibacterial agent (polycationic-π antibacterial agent prepared in Example 1) onto a single surface of a fabric (polyethylene terephthalate fabric) to prepare the antibacterial fabric;

[0139] The mass of the antibacterial agent in the antibacterial fabric is 1% of the mass of the fabric.

[0140] The moisture evaporation rate of the antibacterial fabric finally prepared is 0.82g / h. The temperature of the antibacterial fabric after being placed on the skin surface sprayed with water for 1 minute is 2.8°C lower than the temperature of the fabric before finishing after being placed on the skin surface sprayed with water for 1 minute. The antibacterial rates of the antibacterial fabric to Escherichia coli, Staphylococcus aureus and Candida albicans are 99.68%, 99.84% and 99.71% respectively; after the antibacterial fabric is washed 50 times, the antibacterial rates to Escherichia coli, Staphylococcus aureus and Candida albicans are 96.74%, 96.89% and 96.70% respectively; after 100 friction resistance tests, the antibacterial rates to Escherichia coli, Staphylococcus aureus and Candida albicans are 91.82%, 92.11% and 91.91% respectively.

[0141] Example 8

[0142] A method for preparing an antibacterial fabric, specifically comprising: spraying an antibacterial agent (polycationic-π antibacterial agent prepared in Example 2) onto a single surface of a fabric (polybutylene terephthalate-adipate fabric) to prepare the antibacterial fabric;

[0143] The mass of the antibacterial agent in the antibacterial fabric is 5% of the mass of the fabric.

[0144] The moisture evaporation rate of the antibacterial fabric finally prepared is 0.65g / h. The temperature of the antibacterial fabric after being placed on the skin surface sprayed with water for 1 minute is 2.2°C lower than the temperature of the fabric before finishing after being placed on the skin surface sprayed with water for 1 minute. The antibacterial rates of the antibacterial fabric to Escherichia coli, Staphylococcus aureus and Candida albicans are 98.75%, 99.56% and 97.72% respectively; after being washed 50 times, the antibacterial rates of the antibacterial fabric to Escherichia coli, Staphylococcus aureus and Candida albicans are 96.29%, 96.37% and 95.55% respectively; after 100 friction resistance tests, the antibacterial rates of the antibacterial fabric to Escherichia coli, Staphylococcus aureus and Candida albicans are 93.35%, 93.73% and 93.66% respectively.

[0145] Example 9

[0146] A method for preparing an antibacterial fabric, specifically comprising: spraying an antibacterial agent (polycationic-π antibacterial agent prepared in Example 3) onto a single surface of a fabric (polylactic acid fabric) to prepare the antibacterial fabric;

[0147] The mass of the antibacterial agent in the antibacterial fabric is 3.5% of the mass of the fabric.

[0148] The moisture evaporation rate of the antibacterial fabric finally prepared is 0.68g / h. The temperature of the antibacterial fabric after being placed on the skin surface sprayed with water for 1 minute is 2.2°C lower than the temperature of the fabric before finishing after being placed on the skin surface sprayed with water for 1 minute. The antibacterial rates of the antibacterial fabric to Escherichia coli, Staphylococcus aureus and Candida albicans are 98.29%, 98.79% and 98.40% respectively; after being washed 50 times, the antibacterial rates of the antibacterial fabric to Escherichia coli, Staphylococcus aureus and Candida albicans are 95.99%, 96.34% and 95.74% respectively; after 100 friction resistance tests, the antibacterial rates of the antibacterial fabric to Escherichia coli, Staphylococcus aureus and Candida albicans are 90.01%, 90.83% and 90.23% respectively.

[0149] Example 10

[0150] A method for preparing an antibacterial fabric, specifically comprising: spraying an antibacterial agent (polycationic-π antibacterial agent prepared in Example 4) onto a single surface of a fabric (polyethylene fabric) to prepare the antibacterial fabric;

[0151] The mass of the antibacterial agent in the antibacterial fabric is 5% of the mass of the fabric.

[0152] The moisture evaporation rate of the antibacterial fabric finally prepared is 0.72g / h. The temperature of the antibacterial fabric after being placed on the skin surface sprayed with water for 1 minute is 2.3°C lower than the temperature of the fabric before finishing after being placed on the skin surface sprayed with water for 1 minute. The antibacterial rates of the antibacterial fabric to Escherichia coli, Staphylococcus aureus and Candida albicans are 97.85%, 98.32% and 97.60% respectively; after the antibacterial fabric is washed 50 times, the antibacterial rates to Escherichia coli, Staphylococcus aureus and Candida albicans are 95.42%, 95.87% and 95.18% respectively; after 100 friction resistance tests, the antibacterial rates to Escherichia coli, Staphylococcus aureus and Candida albicans are 90.05%, 90.63% and 90.01% respectively.

[0153] Embodiment 11

[0154] A method for preparing an antibacterial fabric, specifically comprising: spraying an antibacterial agent (polycationic-π antibacterial agent prepared in Example 5) onto a single surface of a fabric (polyisophthalamide fabric) to prepare the antibacterial fabric;

[0155] The mass of the antibacterial agent in the antibacterial fabric is 3.5% of the mass of the fabric.

[0156] The moisture evaporation rate of the antibacterial fabric finally prepared is 0.76g / h. The temperature of the antibacterial fabric after being placed on the skin surface sprayed with water for 1 minute is 2.4°C lower than the temperature of the fabric before finishing after being placed on the skin surface sprayed with water for 1 minute. The antibacterial rates of the antibacterial fabric to Escherichia coli, Staphylococcus aureus and Candida albicans are 99.71%, 99.83% and 99.44% respectively; after the antibacterial fabric is washed 50 times, the antibacterial rates to Escherichia coli, Staphylococcus aureus and Candida albicans are 98.39%, 98.64% and 98.03% respectively; after 100 friction resistance tests, the antibacterial rates to Escherichia coli, Staphylococcus aureus and Candida albicans are 96.40%, 97.23% and 96.69% respectively.

[0157] Example 12

[0158] A method for preparing an antibacterial fabric, specifically comprising: spraying an antibacterial agent (polycationic-π antibacterial agent prepared in Example 6) onto a single surface of a fabric (heterocyclic polybenzimidazole fabric) to prepare the antibacterial fabric;

[0159] The mass of the antibacterial agent in the antibacterial fabric is 5% of the mass of the fabric.

[0160] The moisture evaporation rate of the antibacterial fabric finally prepared is 0.77g / h. The temperature of the antibacterial fabric after being placed on the skin surface sprayed with water for 1 minute is 2.6°C lower than the temperature of the fabric before finishing after being placed on the skin surface sprayed with water for 1 minute. The antibacterial rates against Escherichia coli, Staphylococcus aureus and Candida albicans are 99.93%, 99.97% and 99.86% respectively; after the antibacterial fabric is washed 50 times, the antibacterial rates against Escherichia coli, Staphylococcus aureus and Candida albicans are 98.75%, 98.91% and 98.38% respectively; after 100 friction resistance tests, the antibacterial rates against Escherichia coli, Staphylococcus aureus and Candida albicans are 97.25%, 97.65% and 97.10% respectively.

[0161] Embodiment 13

[0162] A method for preparing an antibacterial fabric, specifically comprising: finishing an antibacterial agent (polycationic-π antibacterial agent prepared in Example 2) onto a fabric (polyethylene terephthalate fabric) by impregnation to prepare the antibacterial fabric;

[0163] The bath ratio is 1:20, and the concentration of the antibacterial agent in the immersion solution is 10 g / L.

[0164] The moisture evaporation rate of the antibacterial fabric finally prepared is 0.1g / h. The temperature of the antibacterial fabric after being placed on the skin surface sprayed with water for 1 minute is 0.1°C lower than the temperature of the fabric before finishing after being placed on the skin surface sprayed with water for 1 minute. The antibacterial rates of the antibacterial fabric against Escherichia coli, Staphylococcus aureus and Candida albicans are 99.78%, 99.85% and 99.63% respectively; after being washed 50 times, the antibacterial rates of the antibacterial fabric against Escherichia coli, Staphylococcus aureus and Candida albicans are 95.65%, 96.87% and 96.22% respectively; after 100 friction resistance tests, the antibacterial rates of the antibacterial fabric against Escherichia coli, Staphylococcus aureus and Candida albicans are 91.46%, 91.85% and 91.28% respectively.

[0165] Embodiment 14

[0166] A method for preparing an antibacterial fabric, specifically comprising: spraying an antibacterial agent (polycationic-π antibacterial agent prepared in Example 1) onto a single surface of a fabric (poly(p-phenylene benzobisoxazole) fabric) to prepare the antibacterial fabric;

[0167] The mass of the antibacterial agent in the antibacterial fabric is 3% of the mass of the fabric.

[0168] The moisture evaporation rate of the antibacterial fabric finally prepared is 0.77g / h. The temperature of the antibacterial fabric after being placed on the skin surface sprayed with water for 1 minute is 2.4°C lower than the temperature of the fabric before finishing after being placed on the skin surface sprayed with water for 1 minute. The antibacterial rates against Escherichia coli, Staphylococcus aureus and Candida albicans are 99.35%, 99.58% and 99.22% respectively; after the antibacterial fabric is washed 50 times, the antibacterial rates against Escherichia coli, Staphylococcus aureus and Candida albicans are 98.52%, 98.75% and 98.10% respectively; after 100 friction resistance tests, the antibacterial rates against Escherichia coli, Staphylococcus aureus and Candida albicans are 96.33%, 96.72% and 95.54% respectively.

[0169] Comparative Example 1

[0170] A method for preparing an antibacterial fabric is basically the same as Example 14, except that the antibacterial agent used in this comparative example is an N-aryl substituted biguanide hydrobromide compound prepared in Example 1 of patent CN104230760B.

[0171] The moisture evaporation rate of the antibacterial fabric finally prepared is 0.35g / h. The temperature of the antibacterial fabric after being placed on the skin surface sprayed with water for 1 minute is 0.87°C lower than the temperature of the fabric before finishing after being placed on the skin surface sprayed with water for 1 minute. The antibacterial rates against Escherichia coli, Staphylococcus aureus and Candida albicans are 82.18%, 82.56% and 81.90% respectively; after the antibacterial fabric is washed 50 times, the antibacterial rates against Escherichia coli, Staphylococcus aureus and Candida albicans are 62.88%, 63.67% and 61.97% respectively; after 100 friction resistance tests, the antibacterial rates against Escherichia coli, Staphylococcus aureus and Candida albicans are 37.91%, 38.40% and 36.89% respectively.

[0172] Compared with Example 14, the water evaporation rate of Comparative Example 1 is low, the fabric cooling effect is poor, and the antibacterial washing resistance and friction resistance are poor. This is because the N-aryl substituted biguanide hydrobromide compound has a small molecular weight, the hydrophobic group benzene ring has a greater influence on its hydrophilicity, and the overall hydrophilicity of the antibacterial agent is poor. In addition, due to the short molecular chain, the interaction force with the fabric is easily affected by external environmental factors such as friction and washing, and the bonding fastness with the fabric is poor, resulting in poor washing resistance and friction resistance.

[0173] Comparative Example 2

[0174] A method for preparing an antibacterial fabric is basically the same as Example 14, except that the antibacterial agent used in this comparative example is the guanidine polymer antibacterial agent prepared in Example 1 of patent application CN105566547A.

[0175] The moisture evaporation rate of the antibacterial fabric finally prepared is 0.46g / h. The temperature of the antibacterial fabric after being placed on the skin surface sprayed with water for 1 minute is 0.95°C lower than the temperature of the fabric before finishing after being placed on the skin surface sprayed with water for 1 minute. The antibacterial rates of the antibacterial fabric against Escherichia coli, Staphylococcus aureus and Candida albicans are 91.06%, 91.98% and 90.82% respectively; after being washed 50 times, the antibacterial rates of the antibacterial fabric against Escherichia coli, Staphylococcus aureus and Candida albicans are 69.83%, 70.36% and 69.29% respectively; after 100 friction resistance tests, the antibacterial rates of the antibacterial fabric against Escherichia coli, Staphylococcus aureus and Candida albicans are 56.59%, 57.22% and 54.91% respectively.

[0176] Compared with Example 14, the moisture evaporation rate of Comparative Example 2 is low, the fabric cooling effect is poor, and the antibacterial, washing-resistant and friction-resistant effects are poor. This is because although a guanidine-based polymer antibacterial agent is used, the aromatic ring is located on the polymer side chain, resulting in poor hydrophilic effect, so the moisture evaporation rate is low and the fabric cooling effect is poor; in addition, the guanidine-based polymer antibacterial agent has limited antibacterial effect, and the side chain with large steric hindrance limits its direct formation of a stable interaction with the fabric. Therefore, after being subjected to washing, friction and other factors, the fabric has a poor antibacterial effect.

Claims

1. A polycation-π antibacterial agent, characterized in that The structural formula is one of the following formulas A to F: In the formula, the value range of n1, n2 and n4 is 1-10, the value range of n3 and n5 is 2-50, and X - Cl - PO4 3- 、NO3 - 、CO3 2- or C6H5SO3 - , -M is -OH, -COOCH3 or -Cl.

2. A polycationic antibacterial agent according to claim 1, characterized in that: The number average molecular weight of the polycationic-π antibacterial agent is 500-20000Da, the minimum inhibitory concentration is 1-128μg / mL, and the minimum bactericidal concentration is 1-256μg / mL.

3. A method for preparing a polycationic antibacterial agent as claimed in claim 1, characterized in that: In the presence of a catalyst or in the absence of a catalyst, a polycationic guanidine salt and a compound having a benzene ring in a molar ratio of 0.8-1.2:1 are subjected to melt polymerization or solution polymerization to obtain a polycationic-π antibacterial agent; The structural formula of the cationic guanidine salt is one of the following formulas i to iv: The compound with a benzene ring is one of the following formulas Ⅰ to Ⅳ:

4. The method according to claim 3, characterized in that The process of melt polymerization is: first, heating to 100-160°C under stirring, reacting for 2-12 hours, then heating to 150-260°C, reacting for 1-5 hours, and finally evacuating to a vacuum degree of ≤200Pa, reacting for 0-10 hours.

5. The method according to claim 3, characterized in that: The solvent used for solution polymerization is one or more of dimethyl sulfoxide, N,N-dimethylformamide, water, isopropanol, methanol, ethanol and acetone; the temperature of solution polymerization is 0-130°C, and the time is 0.5-20h.

6. The method according to claim 3, characterized in that The catalyst is an acidic catalyst, a basic catalyst or a metal catalyst, and the added amount of the catalyst is 0.01-0.5% of the total mass of the polycationic guanidine salt and the compound with a benzene ring.

7. An antibacterial fabric, which is made of a fabric treated with an antibacterial agent, and is made of hydrophobic fibers, characterized in that: The antibacterial agent is one or more of compounds A to F, and the structural formulas of compounds A to F correspond to the following formulas A to F: In the formula, the value range of n1, n2 and n4 is 1-10, the value range of n3 and n5 is 2-50, and X - Cl - PO4 3- 、NO3 - 、CO3 2- or C6H5SO3 - , -M is -OH, -COOCH3 or -Cl.

8. The antibacterial fabric according to claim 7, characterized in that: The mass of the antibacterial agent is 1-5% of the mass of the fabric.

9. The antibacterial fabric according to claim 7, characterized in that: The fabric is polyethylene terephthalate fabric, polytrimethylene terephthalate fabric, polybutylene terephthalate fabric, polybutylene terephthalate-adipate fabric, polylactic acid fabric, polyethylene fabric, polypropylene fabric, polyterephthalamide fabric, polyisophthalamide fabric, heterocyclic polybenzimidazole fabric or poly(p-phenylene benzobisoxazole) fabric.

10. The antibacterial fabric according to claim 7, characterized in that: The finishing is carried out by spraying, and the antibacterial agent is only applied to one side of the fabric; the water evaporation rate of the antibacterial fabric is greater than 0.6g / h; the temperature of the antibacterial fabric after being placed on the skin surface sprayed with water for 1 minute is at least 2°C lower than the temperature of the fabric before finishing after being placed on the skin surface sprayed with water for 1 minute.

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