Antibacterial and insect-proof waterborne polyurethane emulsion as well as preparation method and application thereof

Abstract

The invention discloses antibacterial and insect-proof waterborne polyurethane emulsion as well as a preparation method and application thereof, and belongs to the technical field of antibacterial and insect-proof impregnated resin. The emulsion is prepared from the following components in parts by weight: 40 to 50 parts of diisocyanate; 100 to 150 parts of macromolecular polyol; 5-6 parts of a hydrophilic chain extender; 0-13 parts of a small molecule chain extender; 0.3 to 0.6 part of a catalyst; 3.5 to 4.5 parts of a neutralizing agent; 1 to 10 parts of linalool; 120 to 355 parts of a solvent; and 400-500 parts of an ice-water mixture. According to the invention, linalool is introduced into a molecular chain segment of waterborne polyurethane in an end-capping manner, and good antibacterial and insect-proof effects can be achieved without adding any antibacterial agent or antibacterial component containing metal ions.

Description

Technical Field

[0001] The invention belongs to the technical field of antibacterial and insect-proof impregnated resins, and specifically relates to an antibacterial and insect-proof water-based polyurethane emulsion and a preparation method and application thereof. Background Art

[0002] As global awareness of environmental protection increases, many countries and regions have introduced strict environmental regulations to restrict and prohibit the use of volatile organic compounds (VOCs) and harmful organic solvents. These regulations have caused traditional solvent-based polyurethane products in industries such as coatings, adhesives, and leather finishing agents to face huge environmental pressures, which has promoted the research and development and application of waterborne polyurethanes.

[0003] Antibacterial fabric is a fabric that has the function of inhibiting or killing microorganisms such as bacteria, fungi, and viruses. It is endowed with antibacterial properties on the surface of fibers or fabrics through special processing technology. With the improvement of people's requirements for health and hygiene, antibacterial fabrics have been widely used in medical, home, sports, clothing and other fields. Insect-proof fabric is a textile with special functions. It achieves insect-proof effect through special treatment or adding functional additives. This fabric can effectively eliminate or repel common harmful organisms in life, such as mites, mosquitoes, moths, etc., and is widely used in decorative fabrics such as bedding, carpets, mosquito nets, and outdoor clothing. With the large-scale and long-term use of organic synthetic insecticides, mosquito resistance has become increasingly serious, and the impact of insecticides on the environment has also become increasingly significant. In recent years, it has become a trend to find bioactive substances from natural products, especially plants, to replace chemical insecticides.

[0004] In the prior art, contact antibacterial is mainly achieved by chemically bonding quaternary ammonium salt molecules to polyurethane materials; however, quaternary ammonium salt monomers are positively charged and repel each other, and it is not easy to obtain high molecular weight polymers by direct homopolymerization; quaternary ammonium salts are mostly small molecule quaternary ammonium salts or short-chain quaternary ammonium salts, which are difficult to diffuse into and penetrate the cell wall, cannot bind to the cell membrane and destroy the cell membrane structure, resulting in poor antibacterial effect and easy migration. On the other hand, commonly used water-based polyurethanes mainly use ethanolamine and methanol as end-capping agents. The advantage of ethanolamine is that one side is an amine group and the other side is an alcohol group. The amine group reacts quickly with isocyanate, while the alcohol group reacts slowly. This characteristic makes ethanolamine very useful in two-component polyurethanes. After the reaction is completed, ethanolamine can be used to cap the end, exposing the hydroxyl group, and then cross-linking with the isocyanate cross-linking agent; however, the disadvantage of ethanolamine is that the alcohol group part reacts slowly, which may affect the final performance and stability of the polyurethane. Methanol as an end-capping agent has a dissociation temperature of 150 to 155°C in the presence of a catalyst. This means that methanol requires a higher temperature to effectively dissociate. Therefore, there is an urgent need for an aqueous polyurethane emulsion to solve the problems of insufficient antibacterial properties and high pollution of existing antibacterial fabrics. Summary of the invention

[0005] One of the purposes of the present invention is to provide an antibacterial and insect-proof water-based polyurethane emulsion to solve the problem that the existing water-based polyurethane has insufficient antibacterial properties;

[0006] The second object of the present invention is to provide a method for preparing an antibacterial and insect-proof water-based polyurethane emulsion;

[0007] The third object of the present invention is to provide an application of an antibacterial and insect-proof water-based polyurethane emulsion in fabrics to solve the problems of insufficient antibacterial properties and high pollution of existing antibacterial fabrics.

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

[0009] In a first aspect, an antibacterial and insect-proof water-based polyurethane emulsion comprises the following raw materials in parts by weight:

[0010] 40-50 parts of diisocyanate;

[0011] 100-150 parts of macromolecular polyol;

[0012] 5-6 parts of hydrophilic chain extender;

[0013] 0-13 parts of small molecule chain extender;

[0014] 0.3-0.6 parts of catalyst;

[0015] 3.5-4.5 parts of neutralizer;

[0016] 1-10 parts of linalool;

[0017] 120-355 parts of solvent;

[0018] 400-500 parts of ice-water mixture.

[0019] As a further embodiment of the present invention, the diisocyanate is one or a combination of two or more of toluene diisocyanate, isophorone diisocyanate, dicyclohexylmethane diisocyanate, 1,6-hexyl diisocyanate, and tetramethylcyclohexylmethane diisocyanate.

[0020] As a further embodiment of the present invention, the macromolecular polyol is one or a combination of two or more of polytetramethylene glycol, polypropylene glycol, polyethylene glycol and polycarbonate diol.

[0021] As a further embodiment of the present invention, the hydrophilic chain extender is one of dimethylol propionic acid and dimethylol butyric acid.

[0022] As a further embodiment of the present invention, the small molecule chain extender is one or a combination of two or more of 1,4-butanediol, ethylene glycol, isophorone diol, methyl propylene glycol, and neopentyl glycol.

[0023] As a further embodiment of the present invention, the catalyst is one of dibutyltin dilaurate, stannous octoate, and organic bismuth.

[0024] As a further embodiment of the present invention, the neutralizing agent is one of triethylamine and diethanolamine.

[0025] As a further embodiment of the present invention, the solvent is acetone.

[0026] In a second aspect, a method for preparing an antibacterial and insect-proof water-based polyurethane impregnated emulsion comprises the following steps:

[0027] Weigh the raw materials in parts by weight, mix the diisocyanate and the macromolecular polyol uniformly, and react at 85-90° C. for 1.5-2.5 hours;

[0028] Cool down to 75-80° C., add a hydrophilic chain extender, 6-10% of a solvent (according to the weighed weight of the solvent × 6-10%) and 30-50% of a catalyst (according to the weighed weight of the catalyst × 30-50%) and react for 2-3 hours;

[0029] Cool down to 65-70°C, add small molecule chain extender and remaining catalyst, react for 2-3h, add appropriate amount of solvent to reduce viscosity; then add linalool, react at 65-70°C for 1-2h;

[0030] Subsequently, the remaining solvent is added to reduce the viscosity, and the temperature is then lowered to 35-40° C. A neutralizer is added to neutralize for 4-6 minutes, and then the material is discharged and mixed with an ice-water mixture under high-speed shearing to emulsify, thereby obtaining an antibacterial and insect-proof water-based polyurethane emulsion.

[0031] In a third aspect, an application of an antibacterial and insect-proof water-based polyurethane emulsion in fabrics comprises the following steps:

[0032] At room temperature (25-30°C), the fabric is immersed in the antibacterial and insect-proof water-based polyurethane emulsion and taken out after a certain period of time; the impregnated base fabric is squeezed to remove excess impregnation liquid and control the liquid content of the fabric; finally, the squeezed base fabric is placed in an oven for drying to remove the solvent and solidify the resin on the base fabric.

[0033] Compared with the prior art, the present invention has the following beneficial effects:

[0034] 1. The present invention provides an antibacterial and insect-proof water-based polyurethane emulsion, which is prepared by uniformly mixing a macromolecular polyol and a diisocyanate, then adding a hydrophilic chain extender, a small molecule chain extender, a catalyst, and linalool as a capping agent, neutralizing with a neutralizing agent, synthesizing a water-based polyurethane prepolymer, and emulsifying and dispersing to obtain a water-based polyurethane emulsion. The water-based polyurethane is non-toxic, non-distortion-inducing, non-irritating and non-allergic to local areas, and has good biocompatibility. Linalool, as a chain terpene alcohol compound, is a natural antibacterial and insect-proof biological component. Linalool is introduced into the water-based polyurethane molecular chain segment by capping, without adding any antibacterial agent and antibacterial component containing metal ions, and has excellent antibacterial and insect-proof effects, and has stable and excellent antibacterial properties. The textile fabric (textile fabric, etc.) is immersed in the emulsion at room temperature and taken out after a certain period of time. The impregnated base fabric is squeezed to remove excess impregnation liquid and control the liquid content of the fabric. Finally, the squeezed base fabric is placed in an oven for drying, and the solvent is removed to solidify the resin on the base fabric. The textile fabric is impregnated with the emulsion, and the obtained fabric has excellent long-term antibacterial property and less pollution.

[0035] 2. Linalool is a chain terpene alcohol compound with the structural formula It is a colorless liquid with a scent similar to that of fresh lily of the valley, which varies with its source. It comes from camphor wood oil, camphor leaf oil, kiang wood oil, rosewood oil, coriander seed oil, white orchid leaf oil, etc. in nature. The linalool in these plant essential oils is extracted by fractionation with an efficient fractionation column to obtain a natural linalool product with a content of more than 99.9%. Linalool not only has antibacterial effects, but also has good antibacterial activity against Escherichia coli, Proteus, Enterobacter, Staphylococcus, etc. It also has an insect repellent effect. As an acyclic monoterpene, it can repel mosquitoes and flies. Linalool undergoes a nucleophilic substitution reaction between -OH and -NCO groups to generate a stable compound, realize the closure of the -NCO group, and connect it to the molecular chain segment of waterborne polyurethane, which can achieve long-lasting antibacterial and insect repellent effects at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The present invention will be further described below in conjunction with the accompanying drawings.

[0037] Figure 1 It is a reaction mechanism diagram of the waterborne polyurethane synthesis part of the present invention. DETAILED DESCRIPTION

[0038] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0039] Unless otherwise specified, the parameters such as the rate of heating and / or cooling in the present invention are based on the instruments or equipment used and are not particularly limited as long as they meet industry standards.

[0040] An antibacterial and insect-proof water-based polyurethane emulsion comprises the following raw materials in parts by weight:

[0041] 40-50 parts of diisocyanate;

[0042] 100-150 parts of macromolecular polyol;

[0043] 5-6 parts of hydrophilic chain extender;

[0044] 0-13 parts of small molecule chain extender;

[0045] 0.3-0.6 parts of catalyst;

[0046] 3.5-4.5 parts of neutralizer;

[0047] 1-10 parts of linalool;

[0048] 120-355 parts of solvent;

[0049] 400-500 parts of ice-water mixture.

[0050] The method for preparing the antibacterial and insect-proof water-based polyurethane emulsion comprises the following steps:

[0051] Weigh the raw materials in parts by weight, mix the diisocyanate and the macromolecular polyol uniformly, and react at 85-90° C. for 1.5-2.5 hours;

[0052] Cool down to 75-80° C., add a hydrophilic chain extender, 6-10% of a solvent (according to the weighed weight of the solvent × 6-10%) and 30-50% of a catalyst (according to the weighed weight of the catalyst × 30-50%) and react for 2-3 hours;

[0053] Cool down to 65-70°C, add small molecule chain extender and remaining catalyst, react for 2-3h, add appropriate amount of solvent to reduce viscosity; then add linalool, react at 65-70°C for 1-2h;

[0054] Then, the remaining solvent was added to reduce the viscosity, and the temperature was lowered to 35-40°C. After adding a neutralizer and neutralizing for 4-6 minutes, the material was discharged and mixed with an ice-water mixture under high-speed shearing to emulsify and obtain an antibacterial and insect-proof water-based polyurethane emulsion. The reaction mechanism of the water-based polyurethane synthesis part is shown in the figure. Figure 1 As shown;

[0055] The application of the antibacterial and insect-proof water-based polyurethane emulsion in fabrics comprises the following steps:

[0056] Under room temperature, the textile fabric is immersed in the antibacterial and insect-proof water-based polyurethane emulsion and taken out after a certain period of time; the impregnated base fabric is squeezed to remove excess impregnation liquid and control the liquid content of the fabric; finally, the squeezed base fabric is placed in an oven for drying to remove the solvent and solidify the resin on the base fabric.

[0057] In a specific embodiment, the diisocyanate is toluene diisocyanate, isophorone diisocyanate, dicyclohexylmethane diisocyanate, 1,6-hexyl diisocyanate, tetramethylcyclohexylmethane diisocyanate, or a combination of two or more thereof.

[0058] In a specific embodiment, the macromolecular polyol is one or a combination of two or more of polytetramethylene glycol, polypropylene glycol, polyethylene glycol, and polycarbonate diol.

[0059] In a specific embodiment, the hydrophilic chain extender is one of dimethylol propionic acid and dimethylol butyric acid.

[0060] In a specific embodiment, the small molecule chain extender is one or a combination of two or more of 1,4-butanediol, ethylene glycol, isophorone diol, methyl propylene glycol, and neopentyl glycol.

[0061] In a specific embodiment, the catalyst is one of dibutyltin dilaurate, stannous octoate, and organic bismuth.

[0062] In a specific embodiment, the neutralizing agent is one of triethylamine and diethanolamine.

[0063] In a specific embodiment, the solvent is acetone.

[0064] Example 1

[0065] An antibacterial and insect-proof water-based polyurethane emulsion comprises the following raw materials in parts by weight:

[0066] Diisocyanate (isophorone diisocyanate) 50g;

[0067] 150g of macromolecular polyol (polytetramethylene glycol);

[0068] Hydrophilic chain extender (dimethylolpropionic acid) 5g;

[0069] Small molecule chain extender (neopentyl glycol) 1.7 g;

[0070] Catalyst (dibutyltin dilaurate) 0.5 g;

[0071] Neutralizing agent (triethylamine) 3.8g;

[0072] Linalool 8g;

[0073] Solvent (acetone) 350g;

[0074] 500g ice water mixture.

[0075] The method for preparing the antibacterial and insect-proof water-based polyurethane emulsion comprises the following steps:

[0076] Weigh the raw materials in parts by weight, evenly mix 50 g of isophorone diisocyanate and 150 g of polytetrahydrofuran diol, and slowly heat to 90° C. to react for 2 h;

[0077] Cool down to 80°C, add 5g dimethylolpropionic acid, 25g acetone and 0.2g dibutyltin dilaurate and react for 2h;

[0078] Cool down to 65°C, add 1.7g neopentyl glycol and the remaining 0.3g dibutyltin dilaurate, react for 2h, add appropriate amount of acetone to reduce viscosity; then add 8g linalool, react at 65°C for 1h;

[0079] Subsequently, the remaining amount of acetone was added to reduce the viscosity, and the temperature was lowered to 40° C. 3.8 g of triethylamine was added for neutralization for 5 minutes, and the material was discharged and mixed with 500 g of ice-water mixture under high-speed shearing to obtain an antibacterial and insect-proof water-based polyurethane emulsion.

[0080] Example 2

[0081] An antibacterial and insect-proof water-based polyurethane emulsion is different from Example 1 in that the amount of linalool is replaced by 3 g, and the other raw material components remain the same. The preparation method of the antibacterial and insect-proof water-based polyurethane emulsion comprises the following steps:

[0082] Weigh the raw materials in parts by weight, evenly mix 50 g of isophorone diisocyanate and 150 g of polytetrahydrofuran diol, and slowly heat to 90° C. to react for 2 h;

[0083] Cool down to 80°C, add 5g dimethylolpropionic acid, 25g acetone and 0.2g dibutyltin dilaurate and react for 2h;

[0084] Cool down to 65°C, add 1.7g neopentyl glycol and the remaining 0.3g dibutyltin dilaurate, react for 2h, add appropriate amount of acetone to reduce viscosity; then add 3g linalool, react at 65°C for 1h;

[0085] Subsequently, the remaining amount of acetone was added to reduce the viscosity, and the temperature was lowered to 40° C. 3.8 g of triethylamine was added for neutralization for 5 minutes, and the material was discharged and mixed with 500 g of ice-water mixture under high-speed shearing to obtain an antibacterial and insect-proof water-based polyurethane emulsion.

[0086] Example 3

[0087] An antibacterial and insect-proof water-based polyurethane emulsion is different from Example 1 in that the amount of linalool is replaced with 5 g, and the other raw material components remain the same. The preparation method of the antibacterial and insect-proof water-based polyurethane emulsion comprises the following steps:

[0088] Weigh the raw materials in parts by weight, evenly mix 50 g of isophorone diisocyanate and 150 g of polytetrahydrofuran diol, and slowly heat to 90° C. to react for 2 h;

[0089] Cool down to 80°C, add 5g dimethylolpropionic acid, 25g acetone and 0.2g dibutyltin dilaurate and react for 2h;

[0090] Cool down to 65°C, add 1.7g neopentyl glycol and the remaining 0.3g dibutyltin dilaurate, react for 2h, add appropriate amount of acetone to reduce viscosity; then add 5g linalool, react at 65°C for 1h;

[0091] Subsequently, the remaining amount of acetone was added to reduce the viscosity, and the temperature was lowered to 40° C. 3.8 g of triethylamine was added for neutralization for 5 minutes, and the material was discharged and mixed with 500 g of ice-water mixture under high-speed shearing to obtain an antibacterial and insect-proof water-based polyurethane emulsion.

[0092] Comparative Example 1

[0093] A method for preparing an aqueous polyurethane emulsion, which is different from Example 1 in that linalool is not added, and the other raw material components remain the same. The method for preparing the aqueous polyurethane emulsion comprises the following steps:

[0094] Weigh the raw materials in parts by weight, evenly mix 50 g of isophorone diisocyanate and 150 g of polytetrahydrofuran diol, and slowly heat to 90° C. to react for 2 h;

[0095] Cool down to 80°C, add 5g dimethylolpropionic acid, 25g acetone and 0.2g dibutyltin dilaurate and react for 2h;

[0096] The temperature was lowered to 65°C, and 1.7 g of neopentyl glycol and the balance of 0.3 g of dibutyltin dilaurate were added. The mixture was reacted for 2 h, during which an appropriate amount of acetone was added to reduce the viscosity.

[0097] Subsequently, the remaining amount of acetone was added to reduce the viscosity, and the temperature was lowered to 40° C. 3.8 g of triethylamine was added for neutralization for 5 minutes, and the material was discharged and mixed and emulsified with 500 g of ice-water mixture under high-speed shearing to obtain a water-based polyurethane emulsion.

[0098] Comparative Example 2

[0099] A method for preparing an aqueous polyurethane emulsion, which is different from Example 1 in that 8 g of linalool is replaced by 3.2 g of ethanolamine, and the other raw material components remain the same. The method for preparing the aqueous polyurethane emulsion comprises the following steps:

[0100] Weigh the raw materials in parts by weight, evenly mix 50 g of isophorone diisocyanate and 150 g of polytetrahydrofuran diol, and slowly heat to 90° C. to react for 2 h;

[0101] Cool down to 80°C, add 5g dimethylolpropionic acid, 25g acetone and 0.2g dibutyltin dilaurate and react for 2h;

[0102] Cool down to 65°C, add 1.7g neopentyl glycol and the remaining 0.3g dibutyltin dilaurate, react for 2h, add appropriate amount of acetone to reduce viscosity; then add 3.2g ethanolamine, react at 65°C for 1h;

[0103] Subsequently, the remaining amount of acetone was added to reduce the viscosity, and the temperature was lowered to 40° C. 3.8 g of triethylamine was added for neutralization for 5 minutes, and the material was discharged and mixed and emulsified with 500 g of ice-water mixture under high-speed shearing to obtain a water-based polyurethane emulsion.

[0104] Comparative Example 3

[0105] A method for preparing an aqueous polyurethane emulsion, which is different from Example 1 in that 8 g of linalool is replaced by 1.2 g of ethanolamine, and the other raw material components remain the same. The method for preparing the aqueous polyurethane emulsion comprises the following steps:

[0106] Weigh the raw materials in parts by weight, evenly mix 50 g of isophorone diisocyanate and 150 g of polytetrahydrofuran diol, and slowly heat to 90° C. to react for 2 h;

[0107] Cool down to 80°C, add 5g dimethylolpropionic acid, 25g acetone and 0.2g dibutyltin dilaurate and react for 2h;

[0108] Cool down to 65°C, add 1.7g neopentyl glycol and the remaining 0.3g dibutyltin dilaurate, react for 2h, add appropriate amount of acetone to reduce viscosity; then add 1.2g ethanolamine, react at 65°C for 1h;

[0109] Subsequently, the remaining amount of acetone was added to reduce the viscosity, and the temperature was lowered to 40° C. 3.8 g of triethylamine was added for neutralization for 5 minutes, and the material was discharged and mixed and emulsified with 500 g of ice-water mixture under high-speed shearing to obtain a water-based polyurethane emulsion.

[0110] Comparative Example 4

[0111] A method for preparing an aqueous polyurethane emulsion, which is different from Example 1 in that 8 g of linalool is replaced by 4.5 g of methanol, and the other raw material components remain the same. The method for preparing the aqueous polyurethane emulsion comprises the following steps:

[0112] Weigh the raw materials in parts by weight, evenly mix 50 g of isophorone diisocyanate and 150 g of polytetrahydrofuran diol, and slowly heat to 90° C. to react for 2 h;

[0113] Cool down to 80°C, add 5g dimethylolpropionic acid, 25g acetone and 0.2g dibutyltin dilaurate and react for 2h;

[0114] Cool down to 65°C, add 1.7g neopentyl glycol and the remaining 0.3g dibutyltin dilaurate, react for 2h, add appropriate amount of acetone to reduce viscosity; then add 4.5g methanol, react at 65°C for 1h;

[0115] Subsequently, the remaining amount of acetone was added to reduce the viscosity, and the temperature was lowered to 40° C. 3.8 g of triethylamine was added for neutralization for 5 minutes, and the material was discharged and mixed and emulsified with 500 g of ice-water mixture under high-speed shearing to obtain a water-based polyurethane emulsion.

[0116] The performance of the aqueous polyurethane emulsions prepared in Examples 1 to 3 and Comparative Examples 1 to 4 was tested:

[0117] Mechanical stability: simulated by centrifugal accelerated sedimentation test. Pour an appropriate amount of waterborne polyurethane emulsion into a clean dry centrifuge tube, centrifuge it in a centrifuge for 15 minutes at a speed of 3000r / min. If there is no precipitation in the emulsion after taking it out, it can be proved that the emulsion can be stably stored for 90 days.

[0118] Storage stability: Leave it at room temperature and observe whether stratification occurs. The stratification time is used as the standard for stability determination. The stratification time of an emulsion with poor stability is several days or even hours; the stratification time of an emulsion with good stability is 2 to 3 months; and the stratification time of an emulsion with good stability can reach more than 3 months.

[0119] The test results are shown in Table 1:

[0120] Table 1

[0121] project Mechanical stability Placement stability Example 1 Stable, no precipitation ≥90 days Example 2 Stable, no precipitation ≥90 days Example 3 Stable, no precipitation ≥90 days Comparative Example 1 Unstable, with a lot of precipitation ≤35 days Comparative Example 2 Relatively stable, with a small amount of precipitation ≤80 days Comparative Example 3 Relatively stable, with a small amount of precipitation ≤76 days Comparative Example 4 Unstable, with some precipitation ≤70 days

[0122] It can be seen from Table 1 that the present invention introduces linalool as a capping agent into the aqueous polyurethane emulsion system, so that the system has excellent stability.

[0123] application:

[0124] The aqueous polyurethane emulsions prepared in Examples 1 to 3 and Comparative Examples 1 to 4 are respectively applied to fabrics, comprising the following steps:

[0125] Under room temperature, the textile fabric is immersed in the water-based polyurethane emulsion, and after a certain period of time, the impregnation is evenly taken out; the impregnated base fabric is squeezed to remove excess impregnation liquid and control the liquid content of the fabric; finally, the squeezed base fabric is placed in an oven for drying to remove the solvent and solidify the resin on the base fabric, thereby obtaining 7 groups of impregnated textile fabrics numbered respectively.

[0126] The antibacterial and anti-insect performance tests were conducted on 7 groups of impregnated textile fabrics:

[0127] Antibacterial test: Three circular specimens of equal size were randomly cut from the selected non-woven fabric, placed in a sterile culture dish, and inoculated with Escherichia coli and Staphylococcus aureus. The culture was cultured at a constant temperature for seven days, and the number of colonies growing in the culture dish was observed; colony survival rate = colony number in each experimental group / average colony number in the control experiment.

[0128] Anti-insect test: Three circular samples of equal size are randomly cut from the selected non-woven fabric, and the samples are placed in a sterile culture dish. 40 mites of equal number are put into the culture dish. The culture is carried out under suitable conditions for three days, and the number of mites that survive in the culture dish is observed; mite survival rate = number of surviving mites in each experimental group / initial number of mites in the experimental group.

[0129] The test results are shown in Table 2:

[0130] Table 2

[0131]

[0132]

[0133] From the test data in Table 2, we can see that compared with ethanolamine and methanol, linalool has good antibacterial and insect repellent effects; as a chain terpene alcohol compound, linalool is a natural antibacterial and insect repellent biological component. Linalool is introduced into the molecular chain segment of waterborne polyurethane by end-capping. As the content of linalool increases until it is completely end-capped, the antibacterial and insect repellent ability of the impregnated fabric increases.

[0134] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0135] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. An antibacterial and insect-proof water-based polyurethane emulsion, characterized in that: According to weight parts, it includes the following raw materials: 40-50 parts of diisocyanate; 100-150 parts of macromolecular polyol; 5-6 parts of hydrophilic chain extender; 0-13 parts of small molecule chain extender; Catalyst 0.3-0.6 parts; 3.5-4.5 parts of neutralizer; 1-10 parts of linalool; 120-355 parts of solvent; 400-500 parts of ice-water mixture.

2. The antibacterial and insect-proof aqueous polyurethane emulsion according to claim 1, characterized in that: The diisocyanate is one or a combination of two or more of toluene diisocyanate, isophorone diisocyanate, dicyclohexylmethane diisocyanate, 1,6-hexyl diisocyanate, and tetramethylcyclohexylmethane diisocyanate.

3. The antibacterial and insect-proof aqueous polyurethane emulsion according to claim 1, characterized in that: The macromolecular polyol is one or a combination of two or more of polytetramethylene glycol, polypropylene glycol, polyethylene glycol and polycarbonate diol.

4. The antibacterial and insect-proof aqueous polyurethane emulsion according to claim 1, characterized in that: The hydrophilic chain extender is one of dimethylol propionic acid and dimethylol butyric acid.

5. The antibacterial and insect-proof aqueous polyurethane emulsion according to claim 1, characterized in that: The small molecule chain extender is one or a combination of two or more of 1,4-butanediol, ethylene glycol, isophorone diol, methyl propylene glycol and neopentyl glycol.

6. The antibacterial and insect-proof water-based polyurethane emulsion according to claim 1, characterized in that: The neutralizing agent is one of triethylamine and diethanolamine.

7. The antibacterial and insect-proof aqueous polyurethane emulsion according to claim 1, characterized in that: The solvent is acetone.

8. A method for preparing the antibacterial and insect-proof water-based polyurethane emulsion according to claim 1, characterized in that: The following steps are involved: Weigh the raw materials in parts by weight, mix the diisocyanate and the macromolecular polyol uniformly, and react at 85-90° C. for 1.5-2.5 hours; Cool down to 75-80°C, add hydrophilic chain extender, 6-10% solvent and 30-50% catalyst and react for 2-3h; Cool down to 65-70°C, add small molecule chain extender and remaining catalyst, react for 2-3h, add solvent to reduce viscosity; then add linalool, react at 65-70°C for 1-2h; Add the remaining solvent to reduce the viscosity, then cool to 35-40°C, add a neutralizer to neutralize for 4-6 minutes, and then mix the discharged material with an ice-water mixture for emulsification to obtain an antibacterial and insect-proof water-based polyurethane emulsion.

9. Use of the antibacterial and insect-proof aqueous polyurethane emulsion according to claim 1 in fabrics, characterized in that: The following steps are involved: Under room temperature, immerse the fabric in the antibacterial and insect-proof water-based polyurethane emulsion, immerse it evenly, take it out, squeeze out the excess impregnation liquid and then dry it.

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