Antibacterial polyurethane functional material as well as preparation method and application thereof

Abstract

The invention relates to the technical field of polyurethane modified coatings, and discloses an antibacterial polyurethane functional material as well as a preparation method and application thereof, and the preparation method comprises the following steps: oxidizing graphite under a strong acidic condition to obtain G0; g0, EDA and DMF are mixed and subjected to ultrasonic treatment until a sample is placed on a magnet, magnetism is observed, and graphene oxide powder is obtained through washing and drying; the preparation method comprises the following steps: mixing graphene oxide powder with polyol, and performing ultrasonic treatment to obtain a polymer dispersion; the preparation method comprises the following steps: mixing isocyanate, an acrylic acid compound, a polymerization inhibitor and a catalyst, and reacting to prepare a prepolymer; mixing polyol with the polymer dispersion, adding a catalyst, and adding the prepolymer to obtain a modified polyurethane coating base material; and adding a photoinitiator into the modified polyurethane coating base material to produce the antibacterial polyurethane functional material which is cured into a film. The light-cured polyurethane shoe and clothing coating prepared under the action of a magnetic field has good antibacterial property and heat dissipation or heat preservation performance.

Description

Technical Field

[0001] The invention relates to the technical field of polyurethane modified coatings, and in particular to an antibacterial polyurethane functional material and a preparation method and application thereof. Background Art

[0002] As people pay more and more attention to personal health and environmental protection, the demand for the application of antibacterial materials in consumer goods such as footwear and clothing is also increasing. Footwear and clothing materials need not only to have good comfort and aesthetics, but also to have excellent antibacterial properties to deal with problems such as odor and infection caused by microorganisms such as bacteria and fungi. However, the existing antibacterial coating technology has the following technical problems in practical applications: the functional materials of footwear and clothing need not only to provide a comfortable wearing experience, but also to have good heat dissipation or thermal insulation effects. Existing polyurethane coatings are mostly used to improve comfort, but have certain limitations in heat dissipation or thermal insulation effects, and it is difficult to meet the needs of different climates and environments. In addition, antibacterial coatings often focus on antibacterial effects, and it is difficult to take into account both antibacterial properties and thermal conductivity in the same material, resulting in the inability to achieve ideal comprehensive performance in practical applications. Summary of the invention

[0003] In view of this, the present invention proposes an antibacterial polyurethane functional material and a preparation method and application thereof, aiming to solve the problem in the current technology that antibacterial properties cannot be taken into account with heat dissipation or heat preservation.

[0004] On the one hand, the present invention provides a method for preparing an antibacterial polyurethane functional material, comprising the following steps: S1: Based on the Hummers method, graphite is oxidized under strong acidic conditions to obtain G0; Mixing G0, EDA and DMF by ultrasonication until the sample is placed on a magnet and magnetism is observed, and then washing and drying in a vacuum oven to obtain functionalized graphene oxide powder; S2: mixing the graphene oxide powder with a polyol, and maintaining the mixture under an ultrasonic environment for 7-8 hours to obtain a polymer dispersion; S3: mixing isocyanate, acrylic compound, polymerization inhibitor and catalyst and reacting them to obtain a prepolymer; A catalyst is added after mixing the polyol and the polymer dispersion, and then the prepolymer is added in batches, and the reaction is carried out at 65° C. for 3-4 hours until the NCO value is less than 0.5%, thereby obtaining a modified polyurethane coating base material; S4: Under light-proof conditions, add a photoinitiator to the modified polyurethane coating base material, stir at 30°C for 0.5-0.8h to mix evenly, pour into a mold with a magnetic field, let it stand for 1-3 minutes under a uniform magnetic field, and irradiate with an ultraviolet lamp for 4-8min to obtain a cured film-forming antibacterial polyurethane functional material.

[0005] Furthermore, in step S3, isocyanate, acrylic compound, polymerization inhibitor and catalyst are mixed and reacted at 55° C. for 2-3 hours to obtain the prepolymer.

[0006] Furthermore, the polyol is one or more of isophorone diisocyanate, hexamethylene diisocyanate, toluene-2,4-diisocyanate and diphenylmethane diisocyanate.

[0007] Furthermore, the catalyst is one or more of methanesulfonic acid, triphenylphosphine, dibutyltin dilaurate, bismuth neodecanoate, and bismuth isooctanoate.

[0008] Furthermore, the acrylic compound is one or more of hydroxyethyl acrylate, hydroxyethyl methacrylate and pentaerythritol triacrylate.

[0009] Furthermore, the polymerization inhibitor is p-hydroxyanisole.

[0010] Furthermore, the photoinitiator is one or more of phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide, 2-hydroxy-2methyl-1-phenylpropanone and 1-hydroxy-cyclohexylphenylketone.

[0011] Furthermore, when the direction of the magnetic field is perpendicular or parallel to the plane where the antibacterial polyurethane functional material solidified into a film in the mold is located; When in a vertical relationship, the antibacterial polyurethane functional material exhibits a heat preservation effect; When in a parallel relationship, the antibacterial polyurethane functional material exhibits a heat dissipation effect.

[0012] On the other hand, the present invention also provides an antibacterial polyurethane functional material obtained according to the above preparation method.

[0013] In another aspect, the present invention also provides an application of an antibacterial polyurethane functional material as a coating material for footwear and clothing.

[0014] In terms of functionalization and dispersion performance improvement of graphene oxide of the present invention: graphene oxide is functionalized by reacting with ethylenediamine (EDA), and the amino group (-NH 2) groups react with the hydroxyl (-OH) or carboxyl (-COOH) groups on the graphene oxide surface to introduce ethylenediamine groups to the graphene oxide surface or edge. Functionalized graphene oxide not only improves its dispersibility, but also increases its compatibility with polyurethane materials. Through this process, the surface properties of graphene oxide are changed, enabling it to better interact with other substances and enhance the stability and functionality of the composite material.

[0015] Dispersion performance: The functionalized graphene oxide can be effectively dispersed during the polyurethane synthesis process, avoiding the agglomeration problem that may exist in unfunctionalized graphene oxide, which provides a guarantee for the uniformity and performance of the subsequent polyurethane coating.

[0016] Preparation of polymer dispersion: Functionalized graphene oxide powder is mixed with polyol and kept for a certain period of time under ultrasonic conditions to ensure that graphene oxide can be evenly dispersed in the polymer matrix. This process can ensure the good combination of graphene oxide and polyurethane material, and improve the mechanical properties and antibacterial properties of the final coating material.

[0017] Synthesis and reaction of prepolymer: In step S3, the prepolymer is prepared by the reaction of isocyanate, acrylic compound, inhibitor and catalyst. Subsequently, the prepolymer is mixed with polymer dispersion and polyol, and a catalyst is added to react. This process is the core step of polyurethane synthesis, ensuring that the final coating material has the required physical, chemical and antibacterial properties.

[0018] The role of photoinitiator: Adding photoinitiator to the polyurethane coating base material will trigger the photocuring reaction of polyurethane under ultraviolet light. This process can quickly cure the coating into a film, forming a tough polyurethane film. Photocuring technology not only improves production efficiency, but also provides excellent durability for coating materials without affecting material performance.

[0019] Effect of magnetic field: During the curing process, by applying a magnetic field, the functionalized graphene oxide is rearranged under the action of the magnetic field, which helps to improve the thermal properties of the coating. When the direction of the magnetic field is perpendicular to the plane of the coating, the coating material exhibits good thermal insulation performance; when the direction of the magnetic field is parallel to the plane of the coating, the coating exhibits a heat dissipation effect.

[0020] Antibacterial properties: EDTA-functionalized graphene oxide has its own antibacterial properties, which are enhanced by combining with polyurethane. Graphene oxide can form an active interface in the coating, inhibiting the growth and reproduction of bacteria, thereby achieving the antibacterial function of the coating. This property makes the material particularly suitable for use in the field of footwear and clothing, especially in materials that come into direct contact with the skin, which can reduce bacterial growth and provide long-term antibacterial effects.

[0021] Compared with the prior art, the present invention has the following beneficial effects: The present invention utilizes the dispersion performance of ethylenediamine functionalized graphene oxide added in polyurethane synthesis to improve the full dispersion of graphene oxide in its synthesis, rearranges it under the action of a magnetic field and combines it with a method for preparing a photocurable polyurethane shoe and clothing coating, so as to quickly prepare a shoe and clothing coating with antibacterial, heat dissipation or thermal insulation properties, and provides a new direction for the development of the production of new shoe and clothing coatings. DETAILED DESCRIPTION

[0022] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. 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. Example 1

[0023] S1. Preparation of ethylenediamine functionalized graphene oxide: Using the Hummers method: oxidize graphite under strong acidic conditions to obtain graphene oxide (GO); mix GO, ethylenediamine, and DMF by ultrasonication for 7-8 hours until the sample is placed in a glass dish and placed on a magnet and observed to be magnetic; the mass ratio of GO, ethylenediamine, and DMF is 1:5:90. Then wash repeatedly and dry in a vacuum oven to obtain functionalized graphene oxide powder.

[0024] S2. Preparation of polymer dispersion: The functionalized graphene oxide prepared in step S1 was mixed with PEG400 and sonicated in an ultrasonic bath for 7-8 hours.

[0025] S3. Preparation of modified polyurethane shoe coating base material: 0.4 mol of isophorone diisocyanate, p-hydroxyanisole (accounting for 0.02% of the total mass), and catalyst (accounting for 0.05% of the mass fraction of isophorone diisocyanate) were mixed, and the temperature was raised to 55°C. Then, 0.4 mol of hydroxyethyl acrylate was added three times in 2 hours, while the reaction temperature was kept at 55°C to obtain a prepolymer; 0.04 mol of PTMG2000 and 0.016 mol of the polymer dispersion in S2 and the catalyst (accounting for 0.05% of the mass fraction of the polyol) were mixed, and then the synthesized prepolymer was added dropwise for 1.5 hours, and the temperature was raised to 65°C. After the addition was completed, the -NCO value was tested every half an hour until the -NCO content was less than 0.5%, and then a small amount of hydroxyethyl acrylate (accounting for 1% of the mass fraction of the polyol) was added to eliminate the excess -NCO content. This reaction process took 3-4 hours.

[0026] S4. Preparation of modified photocurable polyurethane footwear coating: Add phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide (3% of the total mass fraction) in step S3 under light-proof conditions, stir at 30°C for half an hour to mix evenly, and then pour into a mold with NdFeB magnets on the upper and lower parts. After standing for 1 minute under a uniform magnetic field, irradiate under ultraviolet light for 5 minutes to obtain a polyurethane footwear coating. The direction of the magnetic field is perpendicular to the plane where the antibacterial polyurethane functional material cured into a film in the mold is located.

[0027] This example also provides a photocurable polyurethane shoe and clothing coating based on ethylenediamine functionalized graphene oxide modified by the above method, which has good antibacterial and heat dissipation effects. Example 2

[0028] S1. Preparation of ethylenediamine functionalized graphene oxide: Using the Hummers method: oxidize graphite under strong acidic conditions to obtain graphene oxide (GO); mix GO, ethylenediamine, and DMF by ultrasonication for 7-8 hours until the sample is placed in a glass dish and placed on a magnet and observed to be magnetic; the mass ratio of GO, ethylenediamine, and DMF is 1:5:90. Then wash repeatedly and dry in a vacuum oven to obtain functionalized graphene oxide powder.

[0029] S2. Preparation of polymer dispersion: The functionalized graphene oxide prepared in step S1 was mixed with PEG600 and sonicated in an ultrasonic bath for 7-8 hours.

[0030] S3. Preparation of modified polyurethane shoe coating base material: 0.6 mol of isophorone diisocyanate, p-hydroxyanisole (accounting for 0.02% of the total mass), and catalyst (accounting for 0.05% of the mass fraction of isophorone diisocyanate) were mixed, and the temperature was raised to 55°C. Then, 0.3 mol of hydroxyethyl acrylate was added three times in 2 hours, while the reaction temperature was kept at 60°C to obtain a prepolymer; 0.1 mol of PTMG2000 and 0.3 mol of the polymer dispersion in S2 and the catalyst (accounting for 0.05% of the mass fraction of the polyol) were mixed, and then the synthesized prepolymer was added dropwise for 1.5 hours, and the temperature was raised to 65°C. After the addition was completed, the -NCO value was tested every half an hour until the -NCO content was less than 0.5%, and then a small amount of hydroxyethyl acrylate (accounting for 1% of the mass fraction of the polyol) was added to eliminate the excess -NCO content. This reaction process took 3-4 hours.

[0031] S4. Preparation of modified photocurable polyurethane shoe and clothing coating: Under light-proof conditions, add phenyl bis (2,4,6-trimethylbenzoyl) phosphine oxide (3% of the total mass fraction) in step S3 and stir at 30°C for half an hour to mix evenly, then pour into a mold with NdFeB magnets on both sides. After standing for 1 minute in a uniform magnetic field, irradiate under ultraviolet light for 5 minutes to obtain a polyurethane shoe and clothing coating. The direction of the magnetic field is parallel to the plane where the antibacterial polyurethane functional material that is cured into a film in the mold is located. This example also provides a photocurable polyurethane shoe and clothing coating based on ethylenediamine functionalized graphene oxide modified by the above method, which has good antibacterial and heat preservation effects. Example 3

[0032] This embodiment provides a method for preparing a photocurable polyurethane shoe and clothing coating based on ethylenediamine functionalized graphene oxide, which specifically comprises the following steps: S1. Preparation of ethylenediamine functionalized graphene oxide: Using the Hummers method: oxidize graphite under strong acidic conditions to obtain graphene oxide (GO); mix GO, ethylenediamine, and DMF by ultrasonication for 7-8 hours until the sample is placed in a glass dish and placed on a magnet and observed to be magnetic; the mass ratio of GO, ethylenediamine, and DMF is 1:5:90. Then wash repeatedly and dry in a vacuum oven to obtain functionalized graphene oxide powder.

[0033] S2. Preparation of polymer dispersion: The functionalized graphene oxide prepared in step S1 was mixed with PEG400 and sonicated in an ultrasonic bath for 7-8 hours.

[0034] S3. Preparation of modified polyurethane shoe coating base material: 0.5 mol of isophorone diisocyanate, p-hydroxyanisole (accounting for 0.02% of the total mass), and catalyst (accounting for 0.05% of the mass fraction of isophorone diisocyanate) were mixed, and the temperature was raised to 55°C. Then, 0.3 mol of hydroxyethyl acrylate was added in 3 times within 2 hours, while the reaction temperature was kept at 55-60°C to obtain a prepolymer; 0.05 mol of PTMG2000 and 0.3 mol of the polymer dispersion in S2 and the catalyst (accounting for 0.05% of the mass fraction of the polyol) were mixed, and then the synthesized prepolymer was added dropwise for 1.5 hours, and the temperature was raised to 65°C. After the addition was completed, the -NCO value was tested every half an hour until the -NCO content was less than 0.5%, and then a small amount of hydroxyethyl acrylate (accounting for 1% of the mass fraction of the polyol) was added to eliminate the excess -NCO content. This reaction process took 3-4 hours.

[0035] S4. Preparation of modified photocurable polyurethane footwear coating: Under light-proof conditions, add phenyl bis (2,4,6-trimethylbenzoyl) phosphine oxide (3% of the total mass fraction) in step S3, stir at 30°C for half an hour to mix evenly, and then apply it to the film-forming mold with neodymium iron boron magnets on the top and bottom. After standing for 1 minute in a uniform magnetic field, irradiate under ultraviolet light for 5 minutes to obtain a polyurethane footwear coating. The direction of the magnetic field is perpendicular to the plane where the antibacterial polyurethane functional material that is cured and film-formed in the mold is located. This example also provides a photocurable polyurethane shoe and clothing coating based on ethylenediamine functionalized graphene oxide modified by the above method, which has good antibacterial and heat dissipation effects.

[0036] The performance of Examples 1-3 was tested, and the test items were antibacterial properties, heat dissipation and thermal insulation. The test process and method were as follows: Antimicrobial testing method: The antimicrobial testing was conducted using the method in the Chinese national standard GB / T 20944.3-2008 “Determination of the antimicrobial properties of antimicrobial products”. Specifically, the plate diffusion method (AATCC 100) was used to evaluate the antimicrobial properties by measuring the inhibitory effect of the material on common pathogens (such as Escherichia coli, Staphylococcus aureus, etc.).

[0037] step: The coating material sample is placed on the surface of the culture medium and inoculated with bacteria such as Escherichia coli or Staphylococcus aureus.

[0038] The samples are placed in an incubator and cultured for typically 24 hours.

[0039] The diameter of the inhibition zone was measured to evaluate the antibacterial properties.

[0040] The antibacterial effect is determined by colony count or inhibition zone size.

[0041] Test results: Example 1: The coating material has a significant inhibitory effect on Staphylococcus aureus and Escherichia coli, with the diameters of the inhibition zones being 25 mm and 20 mm respectively, indicating that the coating has strong antibacterial properties.

[0042] Example 2: The antibacterial performance is also excellent, with the diameters of the inhibition zones being 24 mm and 19 mm, still showing good antibacterial effects.

[0043] Example 3: The antibacterial effect is slightly lower than the previous two, but still effective, with the diameters of the inhibition zones being 23 mm and 18 mm, demonstrating the antibacterial properties of the material.

[0044] Heat dissipation test: Testing method: Thermal conductivity test, using a thermal conductivity meter (TPS 2500S) to measure the thermal conductivity of the coating material. A lower thermal conductivity indicates better heat dissipation performance.

[0045] The heat flow and temperature change are measured by contacting the sensor with the sample surface.

[0046] The thermal conductivity is calculated using the formula.

[0047] Infrared thermal imager test: Use an infrared thermal imager (FLIR) to analyze the thermal images of the coating material to detect its surface temperature distribution and heat dissipation capacity.

[0048] Scan the coating surface using an infrared thermal imager.

[0049] Analyze the heat dissipation efficiency of the material based on the temperature changes shown in the image.

[0050] Test results: Example 1: The thermal conductivity of the coating material is 0.35 W / m·K. The thermal image shows that the temperature distribution of the coating surface after continuous heating is uniform, showing a good heat dissipation effect.

[0051] Embodiment 3: The thermal conductivity is 0.40 W / m·K. The heat dissipation performance is slightly inferior to the first two embodiments, but still has good heat dissipation capacity and is suitable for applications with low heat dissipation requirements.

[0052] Thermal insulation test: Testing method: Use a thermal resistance tester to evaluate thermal insulation performance and test the thermal resistance (R value) of the coating material. A higher thermal resistance indicates good thermal insulation performance.

[0053] The thermal conductivity of the coating is measured and the thermal resistance is calculated.

[0054] According to the analysis of thermal resistance value, materials with larger thermal resistance have better thermal insulation effect.

[0055] Thermal stability test: Use a thermogravimetric analyzer (TGA) to test the thermal stability of the coating material to evaluate its heat resistance in a high temperature environment.

[0056] By heating the coating material and recording the mass change, its thermal stability can be observed.

[0057] High thermal stability means that the material retains heat well for a long time.

[0058] Test results: Example 2: Thermal resistance is 2.8 m 2 ·K / W, the thermal stability is also good, the mass loss is less than 2%, showing stronger thermal insulation performance than Example 1.

[0059] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the relevant field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents. Any modification or equivalent replacement that does not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A method for preparing an antibacterial polyurethane functional material, characterized in that: The following steps are involved: S1: Based on the Hummers method, graphite is oxidized under strong acidic conditions to obtain G0; Mixing G0, EDA and DMF by ultrasonication until the sample is placed on a magnet and magnetism is observed, and then washing and drying in a vacuum oven to obtain functionalized graphene oxide powder; S2: mixing the graphene oxide powder with a polyol, and maintaining the mixture under an ultrasonic environment for 7-8 hours to obtain a polymer dispersion; S3: mixing isocyanate, acrylic compound, polymerization inhibitor and catalyst and reacting them to obtain a prepolymer; A catalyst is added after mixing the polyol and the polymer dispersion, and then the prepolymer is added in batches, and the reaction is carried out at 65° C. for 3-4 hours until the NCO value is less than 0.5%, thereby obtaining a modified polyurethane coating base material; S4: Under light-proof conditions, add a photoinitiator to the modified polyurethane coating base material, stir at 30°C for 0.5-0.8h to mix evenly, pour into a mold with a magnetic field, let it stand for 1-3 minutes under a uniform magnetic field, and irradiate with an ultraviolet lamp for 4-8min to obtain a cured film-forming antibacterial polyurethane functional material.

2. The method for preparing the antibacterial polyurethane functional material according to claim 1, characterized in that: In step S3, isocyanate, acrylic compound, polymerization inhibitor and catalyst are mixed and reacted at 55° C. for 2-3 hours to obtain the prepolymer.

3. The method for preparing the antibacterial polyurethane functional material according to claim 1, characterized in that: The polyol is one or more of isophorone diisocyanate, 1,6-hexamethylene diisocyanate, toluene-2,4-diisocyanate and diphenylmethane diisocyanate.

4. The method for preparing the antibacterial polyurethane functional material according to claim 1, characterized in that: The catalyst is one or more of methanesulfonic acid, triphenylphosphine, dibutyltin dilaurate, bismuth neodecanoate and bismuth isooctanoate.

5. The method for preparing the antibacterial polyurethane functional material according to claim 1, characterized in that: The acrylic compound is one or more of hydroxyethyl acrylate, hydroxyethyl methacrylate and pentaerythritol triacrylate.

6. The method for preparing the antibacterial polyurethane functional material according to claim 1, characterized in that: The polymerization inhibitor is p-hydroxyanisole.

7. The method for preparing the antibacterial polyurethane functional material according to claim 1, characterized in that: The photoinitiator is one or more of phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide, 2-hydroxy-2methyl-1-phenylacetone and 1-hydroxy-cyclohexylphenyl ketone.

8. The method for preparing the antibacterial polyurethane functional material according to claim 1, characterized in that: When the direction of the magnetic field is perpendicular or parallel to the plane where the antibacterial polyurethane functional material solidified into a film in the mold is located; When in a vertical relationship, the antibacterial polyurethane functional material exhibits a heat preservation effect; When in a parallel relationship, the antibacterial polyurethane functional material exhibits a heat dissipation effect.

9. An antibacterial polyurethane functional material obtained according to the preparation method according to any one of claims 1 to 8.

10. Use of the antibacterial polyurethane functional material according to claim 9 as a coating material for footwear and clothing.