阅读说明：本技术 一种含埃洛石的阻燃抗菌复合物及其制备方法 (Halloysite-containing flame-retardant antibacterial compound and preparation method thereof ) 是由 李秋影 张善钰 金谊 吴维光 于 2019-11-12 设计创作，主要内容包括：一种含埃洛石的阻燃抗菌复合物及其制备方法。本发明提供一种含埃洛石纳米管的阻燃抗菌复合物,其为负载有铜单质和磷酸酯的埃洛石纳米管。本发明的含埃洛石纳米管的阻燃抗菌复合物可以均匀分散在聚合物基体中,并可以在赋予聚合物抗菌性能和阻燃性能的同时,不显著影响聚合物的力学性能,扩展聚合物的应用范围。(A flame-retardant antibacterial compound containing halloysite and a preparation method thereof. The invention provides a flame-retardant antibacterial compound containing a halloysite nanotube, which is a halloysite nanotube loaded with a copper simple substance and phosphate. The flame-retardant antibacterial compound containing the halloysite nanotube can be uniformly dispersed in a polymer matrix, and can not significantly influence the mechanical property of the polymer and expand the application range of the polymer while endowing the polymer with antibacterial property and flame retardant property.)

1. The flame-retardant antibacterial compound containing the halloysite nanotube is characterized by being a halloysite nanotube loaded with a copper simple substance and phosphate, wherein in the flame-retardant antibacterial compound, the content of the copper simple substance is 5-15 wt%, and the content of the phosphate is 5-15 wt%.

2. The halloysite nanotube containing flame retardant antimicrobial composite of claim 1, wherein the phosphate is triphenyl phosphate, tricresyl phosphate, or triethyl phosphate.

3. The flame retardant, antimicrobial composite comprising halloysite nanotubes of claim 1, wherein the halloysite nanotubes are silane coupling agent modified halloysite nanotubes.

4. The flame-retardant antibacterial composite containing halloysite nanotubes according to claim 3, wherein the silane coupling agent is a silane coupling agent with amino groups, preferably 3-aminopropyltriethoxysilane, gamma-aminopropyltrimethoxysilane or N-aminoethyl-3-aminopropylmethyldimethoxysilane.

5. A method of making a halloysite nanotube containing flame retardant antimicrobial composite of any one of claims 1-4, comprising:

(1) dispersing the halloysite nanotube modified by the silane coupling agent and soluble copper salt in water, and stirring to obtain a halloysite nanotube loaded with copper ions; preferably, the dosage of the soluble copper salt is 1 to 1.5 times of the mass of the halloysite nanotube modified by the silane coupling agent;

(2) dispersing the copper ion loaded halloysite nanotubes in water, and adding a reducing agent for reaction to obtain copper simple substance loaded halloysite nanotubes; preferably, the amount of the reducing agent is 5-10% of the mass of the copper ion-loaded halloysite nanotube;

(3) dispersing the copper simple substance loaded halloysite nanotubes and phosphate into a solvent to obtain a mixed solution, and loading the phosphate into the halloysite nanotubes by using pressure to obtain a flame-retardant antibacterial compound loaded with the copper simple substance and the phosphate; preferably, the amount of the phosphate is 10-50% of the mass of the halloysite nanotubes loaded with the copper simple substance.

6. The method of claim 5, wherein the method has one or more of the following features:

(a) the silane coupling agent is a silane coupling agent with amino, preferably 3-aminopropyltriethoxysilane, gamma-aminopropyltrimethoxysilane or N-aminoethyl-3-aminopropylmethyldimethoxysilane;

(b) the soluble copper salt is copper chloride, copper sulfate or copper nitrate;

(c) the reducing agent is ascorbic acid or sodium borohydride;

(d) the solvent in the step (3) is acetone or ethanol;

(e) the phosphate is triphenyl phosphate, tricresyl phosphate or triethyl phosphate.

7. The method of claim 5, wherein the method has one or more of the following features:

(A) the step (1) comprises the following steps: dispersing the halloysite nanotube and a silane coupling agent in a solvent, and stirring to obtain a silane coupling agent modified halloysite nanotube; preferably, the mass of the silane coupling agent is 0.5-2 times that of the halloysite nanotube; preferably, the solvent is ethanol or toluene; preferably, the stirring temperature is 50-70 ℃; preferably, the stirring time is 4h-6 h;

(B) in the step (1), the stirring temperature is 50-70 ℃;

(C) in the step (1), stirring for 6-8 h;

(D) in the step (2), the reaction temperature is 75-95 ℃;

(E) in the step (2), the reaction time is 1h-3 h;

(F) in the step (3), the step of loading the phosphate into the halloysite nanotube by using pressure comprises the steps of placing the mixed solution into a vacuum filtration bottle, vacuumizing by using a vacuum pump, then opening a piston, and loading the phosphate into the halloysite nanotube by using atmospheric pressure; preferably, the operation of pumping vacuum by using a vacuum pump, then opening a piston, and loading the phosphate into the halloysite nanotube by using atmospheric pressure is repeated 3 times or more.

8. A fire retardant antimicrobial composite containing halloysite nanotubes prepared by the method of any one of claims 5-7.

9. A polymer composite comprising the halloysite nanotube-containing flame-retardant antimicrobial composite of any one of claims 1-4 or 8; preferably, the polymer composite is a PP composite or a PET composite.

10. Use of a halloysite nanotube containing flame retardant antimicrobial composite according to any one of claims 1-4 or 8 to improve the antimicrobial and/or flame retardant properties of a polymer composite; preferably, the polymer composite is a PP composite or a PET composite.

Technical Field

The invention belongs to the field of polymer composite material additives, and particularly relates to a halloysite-containing flame-retardant antibacterial compound and a preparation method thereof.

Background

In recent years, the polymer industry has been rapidly developed, and plastics have been used in various fields of life. With the increasing living environment and level, it is desirable that the commonly used plastics have both flame retardant and antibacterial properties. Therefore, on the basis of flame retardance, the development trend of plastics is to endow the plastics with antibacterial property. The multifunctional plastic product with flame retardance and antibacterial property has great application value in the emerging fields of aviation and the like.

According to the traditional antibacterial and flame-retardant modification method, an antibacterial agent and a flame retardant are respectively added into a polymer matrix, so that the polymer is endowed with flame retardance and antibacterial property. However, this method requires the addition of various additives, which results in uneven dispersion of flame retardant and antibacterial agent in the polymer, affecting its antibacterial and flame retardant properties, and in addition, reducing the mechanical properties of the polymer, limiting the application of the polymer.

Halloysite Nanotubes (HNTs) are a ubiquitous natural clay nanotube with a crystal structure similar to kaolin, and have the chemical formula Al₂O₃·2SiO₂·2H₂And O. The halloysite nanotube is a multi-walled tubular structure, the outer diameter of a tube cavity is 50-70nm, the inner diameter of an inner cavity is 10-15nm, and the length is about 1 mu m. The inner surface of the tube being Al₂O₃The outer surface of the tube is SiO₂Has abundant hydroxyl groups. Crystal water decomposed from the halloysite nanotube at high temperature can dilute combustible gas and inhibit combustion from spreading, but the flame retardant effect is not obvious when only halloysite is added into polymers, so the halloysite is generally used as a synergistic flame retardant.

Disclosure of Invention

The invention provides a halloysite-containing flame-retardant antibacterial compound which has good compatibility with a polymer, can endow the polymer with flame retardant property and antibacterial property when being added into the polymer, does not obviously influence the mechanical property of the polymer, and further expands the application range of the polymer.

Specifically, the invention provides a flame-retardant antibacterial compound containing a halloysite nanotube, wherein the flame-retardant antibacterial compound is a halloysite nanotube loaded with a copper simple substance and phosphate, and in the flame-retardant antibacterial compound, the content of the copper simple substance is 5 wt% -15 wt%, and the content of the phosphate is 5 wt% -15 wt%.

In one or more embodiments, the phosphate ester is triphenyl phosphate, tricresyl phosphate, or triethyl phosphate.

In one or more embodiments, the halloysite nanotubes are silane coupling agent modified halloysite nanotubes.

In one or more embodiments, the silane coupling agent is an amino-bearing silane coupling agent.

In one or more embodiments, the silane coupling agent is 3-aminopropyltriethoxysilane, gamma-aminopropyltrimethoxysilane, or N-aminoethyl-3-aminopropylmethyldimethoxysilane.

The invention also provides a method for preparing the flame-retardant antibacterial compound containing the halloysite nanotube, which comprises the following steps:

(1) dispersing the halloysite nanotube modified by the silane coupling agent and soluble copper salt in water, and stirring to obtain a halloysite nanotube loaded with copper ions; preferably, the dosage of the copper salt is 1 to 1.5 times of the mass of the halloysite nanotube modified by the silane coupling agent;

(2) dispersing the copper ion loaded halloysite nanotubes in water, and adding a reducing agent for reaction to obtain copper simple substance loaded halloysite nanotubes; preferably, the amount of the reducing agent is 5-10% of the mass of the copper ion-loaded halloysite nanotube; and

(3) dispersing the copper simple substance loaded halloysite nanotubes and phosphate into a solvent to obtain a mixed solution, and loading the phosphate into the halloysite nanotubes by using pressure to obtain a flame-retardant antibacterial compound loaded with the copper simple substance and the phosphate; preferably, the amount of the phosphate is 10-50% of the mass of the halloysite nanotubes loaded with the copper simple substance.

In one or more embodiments, the silane coupling agent is an amino-bearing silane coupling agent, preferably 3-aminopropyltriethoxysilane, gamma-aminopropyltrimethoxysilane or N-aminoethyl-3-aminopropylmethyldimethoxysilane.

In one or more embodiments, the soluble copper salt is copper chloride, copper sulfate, or copper nitrate.

In one or more embodiments, the reducing agent is ascorbic acid or sodium borohydride.

In one or more embodiments, the solvent described in step (3) is acetone or ethanol.

In one or more embodiments, the phosphate ester is triphenyl phosphate, tricresyl phosphate, or triethyl phosphate.

In one or more embodiments, step (1) comprises: dispersing the halloysite nanotube and a silane coupling agent in a solvent, and stirring to obtain a silane coupling agent modified halloysite nanotube; preferably, the mass of the silane coupling agent is 0.5-2 times that of the halloysite nanotube; preferably, the solvent is ethanol or toluene; preferably, the temperature of the stirring is 50-70 ℃; preferably, the stirring time is 4h to 6 h.

In one or more embodiments, the stirring temperature in step (1) is from 50 ℃ to 70 ℃.

In one or more embodiments, the stirring time in step (1) is from 6h to 8 h.

In one or more embodiments, the reaction temperature in step (2) is from 75 ℃ to 95 ℃.

In one or more embodiments, the reaction time in step (2) is from 1h to 3 h.

In one or more embodiments, in the step (3), the loading of the phosphate ester in the halloysite nanotube by pressure is that the mixed solution is placed in a vacuum filtration bottle, vacuum pumping is performed by using a vacuum pump, then a piston is opened, and the phosphate ester is loaded in the halloysite nanotube by using atmospheric pressure; preferably, the operation of pumping vacuum by using a vacuum pump, then opening a piston, and loading the phosphate into the halloysite nanotube by using atmospheric pressure is repeated 3 times or more.

The invention also provides a flame-retardant antibacterial compound containing halloysite nanotubes prepared by the method of any embodiment of the invention.

The invention also provides a polymer composite material containing the halloysite nanotube-containing flame-retardant antibacterial composite according to any embodiment of the invention; preferably, the polymer composite is a PP composite or a PET composite.

The invention also provides application of the flame-retardant antibacterial composite containing the halloysite nanotube in any embodiment of the invention in improving the antibacterial performance and/or the flame-retardant performance of a polymer composite material; preferably, the polymer composite is a PP composite or a PET composite.

Drawings

FIG. 1 is a schematic diagram of the mechanism for preparing the halloysite nanotube-containing flame-retardant antibacterial composite of the invention;

FIG. 2 is an electron micrograph of a halloysite nanotube loaded with elemental copper obtained in example 3;

FIG. 3 is a thermogravimetric plot of halloysite nanotubes and the halloysite nanotubes loaded with tricresyl phosphate and copper simple substance obtained in example 3, wherein HNTs are halloysite nanotubes and T-HNTs are halloysite nanotubes loaded with tricresyl phosphate and copper simple substance;

FIG. 4 is an X-ray energy spectrum (EDS) chart of the halloysite nanotubes loaded with elemental copper obtained in example 3;

fig. 5 is a photograph of inhibition zones of the flame-retardant antibacterial composite containing halloysite nanotubes obtained in example 1 against escherichia coli (e.coli) and streptococcus aureus (s.aureus);

FIG. 6 is a photograph of the inhibition zones of the flame-retardant antibacterial composite containing halloysite nanotubes obtained in example 2 against Escherichia coli and Streptococcus aureus;

FIG. 7 is a photograph of the inhibition zones of the flame retardant and antibacterial composite containing halloysite nanotubes obtained in example 3 against Escherichia coli and Streptococcus aureus.

Detailed Description

To make the features and effects of the present invention comprehensible to those skilled in the art, general description and definitions are made below with reference to terms and expressions mentioned in the specification and claims. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

The theory or mechanism described and disclosed herein, whether correct or incorrect, should not limit the scope of the present invention in any way, i.e., the present disclosure may be practiced without limitation to any particular theory or mechanism.

All features defined herein as numerical ranges or percentage ranges, such as amounts, amounts and concentrations, are for brevity and convenience only. Accordingly, the description of numerical ranges or percentage ranges should be considered to cover and specifically disclose all possible subranges and individual numerical values (including integers and fractions) within the range.

In this context, for the sake of brevity, not all possible combinations of features in the various embodiments or examples are described. Therefore, the respective features in the respective embodiments or examples may be arbitrarily combined as long as there is no contradiction between the combinations of the features, and all the possible combinations should be considered as the scope of the present specification.

The invention utilizes the characteristic that the halloysite nanotube has modifiable inner and outer surfaces and a hollow inner cavity to prepare the flame-retardant antibacterial compound containing the halloysite nanotube. Firstly, modifying a halloysite nanotube by adopting a silane coupling agent with amino to improve the blending performance with a polymer and the mechanical property of the polymer; then modifying the surface of the modified nano-tube with copper nano-particles so as to solve the agglomeration problem of the copper nano-particles and improve the antibacterial property; and the phosphate flame retardant is loaded in the hollow inner cavity of the nanotube, and the phosphate flame retardant and the halloysite nanotube have a synergistic flame retardant effect, so that the flame retardant effect is improved.

Halloysite Nanotubes (HNTs) suitable for use in the present invention can be halloysite nanotubes commonly used as adjuvants for polymer composites. Typically, halloysite nanotubes have a tubular structure with two open ends, a length of 0.2-2 μm, an inner diameter of 10-30nm, and an outer diameter of 40-70 nm. The halloysite nanotubes used in the present invention are commercially available, for example, from toming and high temperature materials ltd, and have a tube length of 0.2-2 μm.

Herein, copper ions, copper simple substance or phosphate ester are supported on the halloysite nanotube, which means that the copper ions, copper simple substance or phosphate ester are bonded on the halloysite nanotube through chemical or physical interaction. Generally, after washing the halloysite nanotubes with a solvent (e.g., water, ethanol, acetone, or toluene), if copper ions, elemental copper, or phosphate are not washed away, it is considered that the copper ions, elemental copper, or phosphate are supported on the halloysite nanotubes. In the invention, copper ions and copper simple substances are usually loaded in the hollow inner cavity of the halloysite nanotube or on the outer side of the tube wall, and phosphate is usually loaded in the hollow inner cavity of the halloysite nanotube.

In the antibacterial flame-retardant compound of the invention, the content of the copper simple substance is usually 5 wt% to 15 wt%, for example 8 wt% to 12 wt%, of the total weight of the antibacterial flame-retardant compound; the phosphate ester is typically present in an amount of 5 wt% to 15 wt%, for example 10 wt% to 15 wt%, based on the total weight of the antimicrobial flame retardant composite.

The halloysite nanotubes of the invention are preferably silane coupling agent modified halloysite nanotubes (hereinafter referred to as modified halloysite nanotubes). The silane coupling agent used for modifying the halloysite nanotubes is not particularly limited, and is preferably a silane coupling agent having an amino group, such as 3-aminopropyltriethoxysilane (coupling agent KH-550), γ -aminopropyltrimethoxysilane (coupling agent A-1110), N-aminoethyl-3-aminopropylmethyldimethoxysilane (coupling agent KH-602), and the like. The amount of silane coupling agent used to modify the halloysite nanotubes is typically 0.5 to 2 times the mass of the halloysite nanotubes.

The copper simple substance loaded on the halloysite nanotube is obtained by reducing copper ions. Typically, the copper ions are derived from soluble copper salts, such as copper chloride, copper sulfate, copper nitrate, and the like. Copper ion-loaded halloysite nanotubes can be prepared by stirring an aqueous solution of a soluble copper salt in which the halloysite nanotubes are dispersed. Typically, copper salts are used in amounts of 1 to 1.5 times the mass of the halloysite nanotubes or modified halloysite nanotubes when preparing copper ion loaded halloysite nanotubes. The concentration of the aqueous solution of the copper salt is usually 0.2 to 1mol/L, preferably 0.5 to 1 mol/L.

The reducing agent for reducing copper ions is not particularly limited, and is preferably sodium borohydride or ascorbic acid. The amount of reducing agent may be an amount conventionally used for reducing copper ions, for example, when sodium borohydride or ascorbic acid is used as the reducing agent, it may be 5% to 10% by mass of the copper ion-loaded halloysite nanotubes.

The phosphate esters suitable for use in the present invention may be various phosphate esters known in the art to be useful as flame retardants, including aromatic phosphate esters and aliphatic phosphate esters such as, but not limited to, triphenyl phosphate, tricresyl phosphate, triethyl phosphate, and the like. Generally, when preparing the halloysite nanotube loaded with phosphate, the phosphate is 10 to 50 percent of the halloysite nanotube loaded with copper simple substance.

FIG. 1 shows the preparation mechanism of the flame-retardant antibacterial composite containing halloysite nanotubes of the invention. The method for preparing the flame-retardant antibacterial compound containing the halloysite nanotube comprises the steps of preparing the halloysite nanotube loaded with copper ions, preparing the halloysite nanotube loaded with a copper simple substance and preparing the halloysite nanotube loaded with the copper simple substance and phosphate.

Generally, the halloysite nanotube loaded with copper ions can be obtained by dispersing a halloysite nanotube and a soluble copper salt in water and stirring.

The present invention preferably uses the silane coupling agent modified halloysite nanotubes described herein to prepare copper ion loaded halloysite nanotubes. The silane coupling agent modified halloysite nanotubes can be prepared by conventional methods, for example, in certain embodiments, the invention disperses halloysite nanotubes and a silane coupling agent into a solvent, and the mixture is refluxed and stirred for 4-6h at 50-70 ℃, and the product is washed and dried to obtain the silane coupling agent modified halloysite nanotubes. Wherein, the mass of the silane coupling agent is preferably 0.5 to 2 times of that of the halloysite nanotube; the solvent may be, for example, ethanol or toluene; the amount of solvent is not particularly critical, and typically from 5 to 20ml of solvent is used per gram of halloysite nanotubes; the dispersion can be ultrasonic dispersion at room temperature for 10-30 min; the washing may be with ethanol or toluene; the drying may be vacuum drying at 60-100 deg.c for 2-8 hr.

In certain embodiments, the step of preparing copper ion loaded halloysite nanotubes comprises: dispersing the halloysite nanotube modified by the silane coupling agent into an aqueous solution of soluble copper salt, stirring for 6-8h at 50-70 ℃, and washing and drying a product to obtain the halloysite nanotube loaded with copper ions. Wherein the addition amount of the copper salt is preferably 1-1.5 times of the mass of the halloysite nanotube; the concentration of the aqueous solution of the copper salt is not particularly limited, and is usually 0.2 to 1mol/L, preferably 0.5 to 1mol/L, for example 0.5 mol/L; the dispersion can be ultrasonic dispersion at room temperature for 10-30 min; the washing may be washing with water; the drying may be vacuum drying at 60-100 deg.c for 2-8 hr. Herein, unless otherwise specified, the water is preferably deionized water.

In certain embodiments, the step of preparing the halloysite nanotubes loaded with elemental copper comprises: and dispersing the copper ion loaded halloysite nanotube in water, slowly heating to 75-95 ℃, adding a reducing agent, stirring for reaction for 1-3h, washing and drying a product to obtain the copper simple substance loaded halloysite nanotube. Wherein the amount of water is not particularly limited, and typically 5-20ml of water is dispersed per gram of halloysite nanotubes; the dispersion can be ultrasonic dispersion at room temperature for 10-30 min; the reducing agent is not particularly limited and may be, for example, sodium borohydride or ascorbic acid; the dosage of the reducing agent is generally 5 to 10 percent of the mass of the copper ion-loaded halloysite nanotube; the washing may be washing with water; the drying may be at 50-80 ℃ for 5-15 h.

The invention utilizes pressure to load phosphate into the halloysite nanotube. In certain embodiments, the step of preparing the halloysite nanotubes loaded with elemental copper and phosphate comprises: dispersing phosphate into a solvent, adding the halloysite nanotube loaded with the copper simple substance, uniformly dispersing to obtain a mixed solution, placing the mixed solution into a vacuum filtration bottle, vacuumizing by using a vacuum pump, opening a piston to allow air to enter, loading the phosphate into the halloysite nanotube by using atmospheric pressure, washing and drying the obtained product to obtain the halloysite nanotube loaded with the copper simple substance and the phosphate, namely the flame-retardant antibacterial compound containing the halloysite nanotube. Among them, the solvent may be, for example, acetone or ethanol; the amount of the solvent is not particularly limited, and usually 50 to 100ml of the solvent is used per gram of the phosphate ester for dispersion; the using amount of the halloysite nanotube loaded with the copper simple substance is preferably 2-10 times of the mass of the phosphate; the dispersion can be ultrasonic dispersion at room temperature for 10-30 min; the vacuumizing time can be 15-30 min; the washing may be with acetone or ethanol; the drying may be at 80-120 deg.c for 5-10 hr. In a preferred embodiment, the operations of evacuating and opening the piston to allow air to enter are repeated 3 or more times to improve the load efficiency.

Generally, the flame-retardant antibacterial composite containing halloysite nanotubes of the invention can be prepared by the following steps:

(a) the halloysite nanotubes are dispersed in a reaction solvent (such as ethanol or toluene), then a silane coupling agent (such as a coupling agent KH-550, a coupling agent A-1110 or a coupling agent KH-602) with the mass of 0.5-2 times that of the halloysite nanotubes is added, and the mixture is ultrasonically dispersed uniformly at room temperature. Then refluxing and stirring for 4-6h at 60 ℃, and washing and drying the obtained product to obtain a silane coupling agent modified halloysite nanotube;

(b) adding the halloysite nanotube modified by the silane coupling agent prepared in the step (a) into a copper salt aqueous solution (such as a copper chloride aqueous solution, a copper sulfate aqueous solution or a copper nitrate aqueous solution), wherein the amount of the copper salt is 100-150% of the mass of the modified halloysite nanotube, the concentration of the copper salt aqueous solution is 0.2-1mol/L, ultrasonically dispersing the mixture uniformly at room temperature, stirring the mixture at 60 ℃ for 6-8h, and washing and drying the obtained product to obtain the halloysite nanotube loaded with copper ions;

(c) dispersing the copper ion-loaded halloysite nanotubes prepared in the step (b) in deionized water, ultrasonically dispersing the halloysite nanotubes uniformly at room temperature, adding a reducing agent (such as ascorbic acid or sodium borohydride) in an amount of 5-10% of the mass of the copper ion-loaded halloysite nanotubes, fully reacting (such as reacting at 75-95 ℃ for 1-3h), washing and drying to obtain copper simple substance-loaded halloysite nanotubes;

(d) dispersing phosphate (such as triphenyl phosphate, tricresyl phosphate or triethyl phosphate) into a reaction solvent (such as acetone or ethanol), adding the halloysite nanotube loaded with the copper simple substance, which is prepared in the step (c) and has the mass 2-10 times of that of the phosphate, ultrasonically dispersing the halloysite nanotube uniformly at room temperature, placing the obtained mixed solution into a vacuum filtration bottle, vacuumizing by using a vacuum pump, opening a piston to enable air to completely enter, loading the phosphate into the halloysite nanotube by using atmospheric pressure, and washing and drying the obtained product to obtain the flame-retardant antibacterial compound of the halloysite nanotube loaded with the copper simple substance and the phosphate.

The flame-retardant antibacterial compound containing the halloysite nanotube is used as an auxiliary agent of a polymer material, so that the antibacterial performance and the flame-retardant performance of the material can be obviously improved, and the mechanical performance of the polymer can not be obviously influenced. Therefore, the invention also comprises the application of the flame-retardant antibacterial composite containing the halloysite nanotubes in improving the antibacterial performance and/or the flame-retardant performance of the polymer composite material, and the polymer composite material containing the flame-retardant antibacterial composite containing the halloysite nanotubes.

In certain embodiments, the polymer in the polymer composite of the present invention is PP or PET.

In certain embodiments, the halloysite nanotube-containing flame-retardant, antimicrobial composite is present in the polymer composite in an amount of 5 wt% to 15 wt%, preferably 6 wt% to 12 wt%, such as 6 wt% to 8 wt%, 8 wt% to 12 wt%, 6 wt% to 10 wt%, 8 wt% to 10 wt%, 9 wt% to 11 wt%, and the like.

The polymer composite may optionally contain various common additives including, but not limited to, antioxidants, thermal stabilizers, and the like. The amount of additives in the polymer composite may be that which is conventional in the art. In certain embodiments, the polymer composites of the present invention comprise or consist of 95 wt% to 85 wt%, preferably 92.5 wt% to 88.5 wt% of a polymer (e.g., PP, PET), 5 wt% to 15 wt%, preferably 6 wt% to 12 wt% of a halloysite nanotube-containing flame retardant antimicrobial compound, 0 to 1 wt%, preferably 0.5 wt% to 1 wt% of an antioxidant (e.g., antioxidant 1010) and 0 to 2 wt%, preferably 1 wt% to 2 wt% of a heat stabilizer (e.g., calcium stearate).

The invention has the following advantages:

1. the halloysite nanotube used is a natural mineral resource, is easy to obtain raw materials, and is economic and environment-friendly;

2. compared with free copper, the copper loaded on the halloysite nanotube has better antibacterial effect;

3. the halloysite nanotube has a synergistic flame retardant effect, a phosphate flame retardant is loaded in an inner cavity to improve the flame retardant effect, and a small amount of the halloysite nanotube-containing flame-retardant antibacterial compound is added to ensure that polymerization can obtain excellent flame retardant performance;

4. the phosphate flame retardant is loaded in the halloysite nanotube, so that the plasticizing effect of the phosphate flame retardant can be reduced, and the influence of the phosphate flame retardant on the mechanical property is reduced;

5. the modified halloysite nanotube has good compatibility with a polymer, and the copper simple substance and the phosphate are loaded on the modified halloysite nanotube, so that the dispersibility of the copper simple substance and the phosphate in the polymer can be improved, and the phenomena of agglomeration and precipitation are avoided.

The invention is further illustrated by the following specific examples. The following examples use instrumentation conventional in the art. The experimental procedures, in which specific conditions are not noted in the following examples, are generally carried out under conventional conditions or conditions recommended by the manufacturers. In the following examples, various starting materials were used, and unless otherwise specified, conventional commercially available products were used. Unless otherwise specified, the percentages in the examples are percentages by mass.

In the following examples, halloysite nanotubes were obtained from tomming and high temperature materials ltd and had a tube length of 0.2 μm to 2 μm; PET is purchased from Zhejiang Sheng Yuan chemical fiber Co., Ltd, and the model is JK-BB; PP was purchased from the Yankee petrochemical company and was model number T30S.