阅读说明：本技术 一种高回弹抑菌tpu发泡材料及其制备方法 (High-resilience antibacterial TPU (thermoplastic polyurethane) foam material and preparation method thereof ) 是由 陈登龙 吴惠民 白欣 刘志鹏 林金火 于 2021-08-11 设计创作，主要内容包括：本发明采用改性石墨烯/壳聚糖插层蒙脱土制备得到新的改性抗菌剂,再将抗菌剂与TPU材料、尼龙弹性体、抗菌剂、硬脂酸、交联剂、调和剂等其他加工助剂经双螺杆挤出机注入超临界CO-(2)、剪切混合、降压挤出、升温发泡、冷却定型等工序,得到高回弹抑菌TPU发泡材料,不仅有效增强抗菌剂的热稳定性,而且克服了在材料加工过程中由于高温引起抗菌剂的失效等问题。同时利用插层技术,将抗菌剂插层至蒙脱土,能有效提高抗菌剂在TPU发泡材料的热稳定性,延缓抗菌剂的释放速度,同时有效提高抗菌剂在基体树脂中的分散性,解决石墨烯或壳聚糖单一组分抗菌剂在基体树脂中分散性不好,容易发生团聚影响材料性能的问题。同时创新性的添加尼龙弹性体,能有效降低无机抗菌剂的加入对发泡材料弹性性能的影响,在提高材料抗菌性能的同时能有效保持和提高材料的弹性性能。(The invention adopts modified graphene/chitosan intercalated montmorillonite to prepare a new modified antibacterial agent, and then the antibacterial agent is mixed with TPU material and nylon elastomerInjecting supercritical CO into other processing aids such as elastomer, antibacterial agent, stearic acid, crosslinking agent, and blending agent via a twin-screw extruder 2 The high-resilience antibacterial TPU foaming material is obtained through the processes of shearing and mixing, decompression and extrusion, heating and foaming, cooling and shaping and the like, so that the thermal stability of the antibacterial agent is effectively enhanced, and the problems of failure of the antibacterial agent caused by high temperature in the material processing process and the like are solved. Meanwhile, the antibacterial agent is intercalated into the montmorillonite by utilizing an intercalation technology, so that the thermal stability of the antibacterial agent in the TPU foaming material can be effectively improved, the release speed of the antibacterial agent is delayed, meanwhile, the dispersity of the antibacterial agent in the matrix resin is effectively improved, and the problem that the material performance is influenced because the graphene or chitosan single-component antibacterial agent is poor in dispersity and is easy to agglomerate in the matrix resin is solved. Meanwhile, the nylon elastomer is innovatively added, so that the influence of the addition of the inorganic antibacterial agent on the elastic performance of the foaming material can be effectively reduced, the antibacterial performance of the material is improved, and the elastic performance of the material can be effectively maintained and improved.)

1. The high-resilience antibacterial TPU foaming material is characterized in that:

the composition is characterized by comprising the following raw materials in parts by weight:

TPU material: 100 parts of (A);

nylon elastomer: 10-20 parts;

antibacterial agents: 1-2 parts;

stearic acid: 1-2 parts;

a crosslinking agent: 1-2 parts;

blending agent: 2-4 parts.

2. The high resilience antibacterial TPU foaming material of claim 1, which is characterized in that: the antibacterial agent is modified graphene/chitosan intercalated montmorillonite.

3. The high resilience antibacterial TPU foaming material of claim 2, wherein the modified graphene/chitosan intercalated montmorillonite antibacterial agent is prepared by the following method:

(1) preparation of modified graphene

The modified graphene oxide is prepared by adopting an improved Hummers method, 10-20 g of graphene oxide is weighed and added into a three-neck flask filled with 100mL of ethanol, 0.5-1 g of coupling agent is added while stirring, the reaction is carried out for 2-4 h at the temperature of 40-60 ℃, and the modified graphene oxide is obtained by suction filtration and drying.

(2) Preparation of modified graphene/chitosan

Accurately weighing 3-5 g of chitosan, adding 200mL of deionized water, stirring, slowly dropping 30-50 g of acetic acid solution with the concentration of 10-20%, and fully stirring for 3-5 h to obtain the chitosan solution. And (2) weighing 3-5 g of the modified graphene prepared in the step (1), slowly adding the modified graphene into the chitosan solution, fully stirring to obtain a uniformly mixed modified graphene/chitosan solution, putting the solution into a vacuum oven, and carrying out vacuum drying at 85 ℃ to obtain the modified graphene/chitosan material.

(3) Preparation of graphene/chitosan intercalated montmorillonite antibacterial agent

Weighing 10-20 g of montmorillonite, adding 600mL of deionized water, stirring and dispersing uniformly at normal temperature, slowly adding 20-40 g of small molecular amine pre-intercalation agent while stirring, fully reacting for 3-6 h, then carrying out ultrasonic treatment for 60-100 min to obtain pre-intercalated montmorillonite suspension, weighing 3-5 g of the modified graphene/chitosan material prepared in the step (2), adding into the pre-intercalated montmorillonite suspension, heating to 60-80 ℃, rapidly and mechanically stirring for 12-24 h to obtain graphene/chitosan intercalated montmorillonite suspension, and filtering, washing and drying to obtain the graphene/chitosan intercalated montmorillonite antibacterial agent.

4. The high resilience antibacterial TPU foaming material of claim 3, wherein: the coupling agent in the step (1) is at least one of silane coupling agent, aluminate coupling agent and titanate coupling agent.

5. The high resilience antibacterial TPU foaming material of claim 3, wherein: the micromolecule amine pre-intercalation agent in the step (3) is at least one of ethylenediamine, hexamethylenediamine, aniline and diethylenetriamine.

6. The high resilience antibacterial TPU foaming material of claim 1, which is characterized in that: the blending agent is prepared from the following components in a mass ratio of 2: 3 diethyl 2-oxopropanoate, ethylene glycol diethyl ether diamine tetraacetic acid; the cross-linking agent is dicumyl peroxide.

7. A preparation method of a high-resilience antibacterial TPU (thermoplastic polyurethane) foam material is characterized by comprising the following steps:

the method comprises the following steps: weighing a TPU material, a nylon elastomer, an antibacterial agent, stearic acid, a cross-linking agent and a blending agent for later use;

step two: sequentially adding the TPU material, the nylon elastomer, the antibacterial agent, the stearic acid, the cross-linking agent and the blending agent into a high-speed mixer, and mixing at a high speed to obtain a premix;

step three: adding the premix obtained in the step two into a double-screw extruder, and injecting supercritical CO₂The high-resilience antibacterial TPU foaming material is obtained through the working procedures of shearing and mixing, pressure reduction and extrusion, temperature rise and foaming, cooling and shaping and the like.

Technical Field

The invention relates to a high polymer material, in particular to a high-resilience antibacterial TPU (thermoplastic polyurethane) foam material.

Background

TPU is a high molecular material between rubber and plastic, is named as thermoplastic polyurethane elastomer rubber, and is an elastomer which can be plasticized by heating and can be dissolved by a solvent. The polyurethane thermoplastic elastomer has the characteristics of excellent wear resistance, excellent ozone resistance, high hardness, high strength, good elasticity, low temperature resistance, good oil resistance, chemical resistance, environmental resistance and the like, and is widely applied to many fields of shoe materials, clothes, pipes, films and sheets, cables, automobiles, construction, medical sanitation, national defense, sports and leisure and the like.

The TPU supercritical foaming material is generally called as 'popcorn', a large number of micro-nano-scale cells are formed inside a product by changing pressure, temperature and the like through supercritical gas raw materials, and the TPU supercritical foaming material is a green and environment-friendly high-performance foaming material. The functional additive is added to make the polymer foaming material obtain different functionalities, such as polymer antibacterial foaming material. But the single-component antibacterial agent such as chitosan, graphene and the like at the present stage has poor compatibility with TPU materials, the antibacterial agent cannot be uniformly dispersed, and the antibacterial agent is easy to fall off from a matrix, so that the antibacterial effect is poor. Meanwhile, the strength of the melt of the matrix material is also affected, the hole wall is easy to collapse, and the resilience performance is poor.

Disclosure of Invention

Aiming at the defects in the prior art, the invention aims to provide a high-resilience antibacterial TPU foaming material.

In order to achieve the purpose, the invention provides the following technical scheme:

a high-resilience antibacterial TPU (thermoplastic polyurethane) foaming material is composed of the following raw materials in parts by weight:

TPU material: 100 parts of (A);

nylon elastomer: 10-20 parts;

antibacterial agents: 1-2 parts;

stearic acid: 1-2 parts;

a crosslinking agent: 1-2 parts;

blending agent: 2-4 parts.

The antibacterial agent is modified graphene/chitosan intercalated montmorillonite, and the preparation method comprises the following steps:

(1) preparation of modified graphene

The modified graphene oxide is prepared by adopting an improved Hummers method, 10-20 g of graphene oxide is weighed and added into a three-neck flask filled with 100mL of ethanol, 0.5-1 g of coupling agent is added while stirring, the reaction is carried out for 2-4 h at the temperature of 40-60 ℃, and the modified graphene oxide is obtained by suction filtration and drying.

(2) Preparation of modified graphene/chitosan

Accurately weighing 3-5 g of chitosan, adding 200mL of deionized water, stirring, slowly dropping 30-50 g of acetic acid solution with the concentration of 10-20%, and fully stirring for 3-5 h to obtain the chitosan solution. And (2) weighing 3-5 g of the modified graphene prepared in the step (1), slowly adding the modified graphene into the chitosan solution, fully stirring to obtain a uniformly mixed modified graphene/chitosan solution, putting the solution into a vacuum oven, and carrying out vacuum drying at 85 ℃ to obtain the modified graphene/chitosan material.

(3) Preparation of modified graphene/chitosan intercalated montmorillonite antibacterial agent

Weighing 10-20 g of montmorillonite, adding 600mL of deionized water, stirring and dispersing uniformly at normal temperature, slowly adding 20-40 g of small molecular amine pre-intercalation agent while stirring, fully reacting for 3-6 h, then carrying out ultrasonic treatment for 60-100 min to obtain pre-intercalated montmorillonite suspension, weighing 3-5 g of modified graphene/chitosan material prepared in the step (2), adding into the pre-intercalated montmorillonite suspension, heating to 60-80 ℃, rapidly and mechanically stirring for 12-24 h to obtain graphene/chitosan intercalated montmorillonite suspension, and filtering, washing and drying to obtain the modified graphene/chitosan intercalated montmorillonite antibacterial agent.

The coupling agent is at least one of silane coupling agent, aluminate coupling agent and titanate coupling agent.

The micromolecule amine pre-intercalation agent is at least one of ethylenediamine, hexamethylenediamine, aniline and diethylenetriamine.

The blending agent is prepared from the following components in a mass ratio of 2: 3 diethyl 2-oxopropanoate, ethylene glycol diethyl ether diamine tetraacetic acid.

The cross-linking agent is dicumyl peroxide.

As another purpose of the invention, the invention provides a preparation method of the high-resilience antibacterial TPU foaming material, which comprises the following steps:

the method comprises the following steps: weighing TPU material, nylon elastomer, antibacterial agent, stearic acid, cross-linking agent and blending agent according to the proportion for later use;

step two: sequentially adding the TPU material, the nylon elastomer, the antibacterial agent, the stearic acid, the cross-linking agent and the blending agent into a high-speed mixer, and mixing at a high speed to obtain a premix;

step three: adding the premix obtained in the step two into a double-screw extruder, and injecting supercritical CO₂The high-resilience antibacterial TPU foaming material is obtained through the working procedures of shearing and mixing, pressure reduction and extrusion, temperature rise and foaming, cooling and shaping and the like.

The invention has the beneficial effects that the novel modified antibacterial agent is prepared by adopting the modified graphene/chitosan intercalated montmorillonite, and then the antibacterial agent and other processing aids such as TPU materials, nylon elastomers, antibacterial agents, stearic acid, cross-linking agents, blending agents and the like are injected into supercritical CO through a double-screw extruder₂The high-resilience antibacterial TPU foaming material is obtained through the working procedures of shearing and mixing, pressure reduction and extrusion, temperature rise and foaming, cooling and shaping and the like. Compared with the traditional TPU foaming material, the material has the advantages thatThe method has the following obvious advantages:

(1) the novel antibacterial agent is prepared by adopting the modified graphene/chitosan intercalated montmorillonite, so that the thermal stability of the antibacterial agent can be effectively enhanced, and the problems of failure of the antibacterial agent and the like caused by high temperature in the material processing process are solved.

(2) The antibacterial agent is intercalated into the montmorillonite by utilizing an intercalation technology, so that the migration speed of the antibacterial agent can be effectively reduced, the release speed of the antibacterial agent is delayed, and the aims of long-acting antibacterial and bacteriostatic of the composite material are fulfilled.

(3) The antibacterial agent is prepared by modifying graphene/chitosan intercalated montmorillonite, so that the dispersibility of the antibacterial agent in matrix resin can be effectively improved, and the problems that the dispersibility of the single-component antibacterial agent of graphene or chitosan in the matrix resin is poor, and the performance of the material is influenced by the easy occurrence of agglomeration are solved. Meanwhile, the nylon elastomer is added, so that the influence of the addition of the antibacterial agent on the elastic performance of the foaming material can be effectively reduced, the antibacterial performance of the material is improved, and the elastic performance of the material can be effectively maintained and improved.

Detailed Description

The present invention will be described in detail with reference to specific examples. The following examples will assist those skilled in the art in further understanding the invention, but are not intended to limit the invention in any way. It should be noted that variations and modifications can be made by persons skilled in the art without departing from the spirit of the invention. All falling within the scope of the present invention.

Example 1:

a high-resilience antibacterial TPU (thermoplastic polyurethane) foaming material is composed of the following raw materials in parts by weight:

TPU material: 100 parts of (A);

nylon elastomer: 10 parts of (A);

modified graphene/chitosan intercalated montmorillonite antibacterial agent: 1 part;

stearic acid: 1 part;

dicumyl peroxide crosslinking agent: 1 part;

the mass ratio is 2: 3 diethyl 2-oxopropanedioate and ethylene glycol diethyl ether diamine tetraacetic acid conditioner: and 2 parts.

The modified graphene/chitosan intercalated montmorillonite antibacterial agent is prepared by the following method:

(1) preparation of modified graphene

Preparing graphene oxide by adopting an improved Hummers method, weighing 10g of graphene oxide, adding the graphene oxide into a three-neck flask filled with 100mL of ethanol, adding 0.5g of silane coupling agent while stirring, reacting for 2h at the temperature of 40 ℃, performing suction filtration, and drying to obtain the modified graphene.

(2) Preparation of modified graphene/chitosan

Accurately weighing 3g of chitosan, adding 200mL of deionized water, stirring, slowly dripping 30g of 10% acetic acid solution, and fully stirring for 3h to obtain the chitosan solution. Weighing 3g of the modified graphene prepared in the step (1), slowly adding the modified graphene into the chitosan solution, fully stirring to obtain a uniformly mixed modified graphene/chitosan solution, putting the solution into a vacuum oven, and carrying out vacuum drying at 85 ℃ to obtain the modified graphene/chitosan material.

(3) Preparation of modified graphene/chitosan intercalated montmorillonite antibacterial agent

Weighing 10g of montmorillonite, adding 600mL of deionized water, stirring and dispersing uniformly at normal temperature, slowly adding 20g of ethylenediamine intercalating agent while stirring, fully reacting for 3h, and then carrying out ultrasonic treatment for 60min to obtain a pre-intercalated montmorillonite suspension, weighing 3g of the modified graphene/chitosan material prepared in the step (2), adding the modified graphene/chitosan material into the pre-intercalated montmorillonite suspension, heating to 60 ℃, rapidly and mechanically stirring for 12h to obtain a modified graphene/chitosan intercalated montmorillonite suspension, and filtering, washing and drying to obtain the modified graphene/chitosan intercalated montmorillonite antibacterial agent.

The preparation method of the high-resilience antibacterial TPU foaming material comprises the following steps:

the method comprises the following steps: weighing a TPU material, a nylon elastomer, a modified graphene/chitosan intercalated montmorillonite antibacterial agent, stearic acid and a dicumyl peroxide crosslinking agent in a mass ratio of 2: 3, 2-oxo-diethyl malonate and ethylene glycol diethyl ether diamine tetraacetic acid blending agent for standby;

step two: the preparation method comprises the following steps of (1) mixing a TPU material, a nylon elastomer, a modified graphene/chitosan intercalated montmorillonite antibacterial agent, stearic acid and a dicumyl peroxide crosslinking agent in a mass ratio of 2: 3, sequentially adding the diethyl 2-oxomalonate and the ethylene glycol diethyl ether diamine tetraacetic acid blending agent into a high-speed mixer, and mixing at a high speed to obtain a premix;

step three: adding the premix obtained in the step two into a double-screw extruder, and injecting supercritical CO₂The high-resilience antibacterial TPU foaming material is obtained through the working procedures of shearing and mixing, pressure reduction and extrusion, temperature rise and foaming, cooling and shaping and the like.

Example 2:

a high-resilience antibacterial TPU (thermoplastic polyurethane) foaming material is composed of the following raw materials in parts by weight:

TPU material: 100 parts of (A);

nylon elastomer: 12 parts of (1);

modified graphene/chitosan intercalated montmorillonite antibacterial agent: 1.2 parts;

stearic acid: 1.5 parts;

dicumyl peroxide crosslinking agent: 1 part;

the mass ratio is 2: 3 diethyl 2-oxopropanedioate and ethylene glycol diethyl ether diamine tetraacetic acid conditioner: and 3 parts.

The modified graphene/chitosan intercalated montmorillonite antibacterial agent is prepared by the following method:

(1) preparation of modified graphene

Preparing graphene oxide by adopting an improved Hummers method, weighing 13g of graphene oxide, adding the graphene oxide into a three-neck flask filled with 100mL of ethanol, adding 0.8g of aluminate coupling agent while stirring, reacting for 3h at the temperature of 50 ℃, performing suction filtration, and drying to obtain the modified graphene.

(2) Preparation of modified graphene/chitosan

Accurately weighing 4g of chitosan, adding 200mL of deionized water, stirring, slowly dripping 45g of 13% acetic acid solution, and fully stirring for 4.5h to obtain the chitosan solution. Weighing 4g of the modified graphene prepared in the step (1), slowly adding the modified graphene into the chitosan solution, fully stirring to obtain a uniformly mixed modified graphene/chitosan solution, putting the solution into a vacuum oven, and carrying out vacuum drying at 85 ℃ to obtain the modified graphene/chitosan material.

(3) Preparation of modified graphene/chitosan intercalated montmorillonite antibacterial agent

Weighing 15g of montmorillonite, adding 600mL of deionized water, stirring and dispersing uniformly at normal temperature, slowly adding 35g of aniline intercalation agent while stirring, fully reacting for 5h, then carrying out ultrasonic treatment for 80min to obtain a pre-intercalated montmorillonite suspension, weighing 4g of modified graphene/chitosan material prepared in the step (2), adding the modified graphene/chitosan material into the pre-intercalated montmorillonite suspension, heating to 75 ℃, rapidly and mechanically stirring for 18h to obtain a modified graphene/chitosan intercalated montmorillonite suspension, and filtering, washing and drying to obtain the modified graphene/chitosan intercalated montmorillonite antibacterial agent. The preparation method of the high-resilience antibacterial TPU foaming material comprises the following steps:

the method comprises the following steps: weighing a TPU material, a nylon elastomer, a modified graphene/chitosan intercalated montmorillonite antibacterial agent, stearic acid and a dicumyl peroxide crosslinking agent in a mass ratio of 2: 3, 2-oxo-diethyl malonate and ethylene glycol diethyl ether diamine tetraacetic acid blending agent for standby;

step two: the preparation method comprises the following steps of (1) mixing a TPU material, a nylon elastomer, a modified graphene/chitosan intercalated montmorillonite antibacterial agent, stearic acid and a dicumyl peroxide crosslinking agent in a mass ratio of 2: 3, sequentially adding the diethyl 2-oxomalonate and the ethylene glycol diethyl ether diamine tetraacetic acid blending agent into a high-speed mixer, and mixing at a high speed to obtain a premix;

step three: adding the premix obtained in the step two into a double-screw extruder, and injecting supercritical CO₂The high-resilience antibacterial TPU foaming material is obtained through the working procedures of shearing and mixing, pressure reduction and extrusion, temperature rise and foaming, cooling and shaping and the like.

Example 3:

a high-resilience antibacterial TPU (thermoplastic polyurethane) foaming material is composed of the following raw materials in parts by weight:

TPU material: 100 parts of (A);

nylon elastomer: 15 parts of (1);

modified graphene/chitosan intercalated montmorillonite antibacterial agent: 1.5 parts;

stearic acid: 1.1 parts;

dicumyl peroxide crosslinking agent: 2 parts of (1);

the mass ratio is 2: 3 diethyl 2-oxopropanedioate and ethylene glycol diethyl ether diamine tetraacetic acid conditioner: 4 parts.

The modified graphene/chitosan intercalated montmorillonite antibacterial agent is prepared by the following method:

(1) preparation of modified graphene

Preparing graphene oxide by adopting an improved Hummers method, weighing 18g of graphene oxide, adding the graphene oxide into a three-neck flask filled with 100mL of ethanol, adding 0.8g of titanate coupling agent while stirring, reacting for 4 hours at the temperature of 50 ℃, performing suction filtration, and drying to obtain the modified graphene.

(2) Preparation of modified graphene/chitosan

Accurately weighing 4.5g of chitosan, adding 200mL of deionized water, stirring, slowly dripping 45g of 17% acetic acid solution, and fully stirring for 4.5h to obtain the chitosan solution. Weighing 4g of the modified graphene prepared in the step (1), slowly adding the modified graphene into the chitosan solution, fully stirring to obtain a uniformly mixed modified graphene/chitosan solution, putting the solution into a vacuum oven, and carrying out vacuum drying at 85 ℃ to obtain the modified graphene/chitosan material.

(3) Preparation of modified graphene/chitosan intercalated montmorillonite antibacterial agent

Weighing 18g of montmorillonite, adding 600mL of deionized water, stirring and dispersing uniformly at normal temperature, slowly adding 35g of hexamethylenediamine intercalator while stirring, fully reacting for 5h, then carrying out ultrasonic treatment for 85min to obtain a pre-intercalated montmorillonite suspension, weighing 4g of the modified graphene/chitosan material prepared in the step (2), adding the modified graphene/chitosan material into the pre-intercalated montmorillonite suspension, heating to 75 ℃, rapidly and mechanically stirring for 20h to obtain a modified graphene/chitosan intercalated montmorillonite suspension, and filtering, washing and drying to obtain the modified graphene/chitosan intercalated montmorillonite antibacterial agent.

The preparation method of the high-resilience antibacterial TPU foaming material comprises the following steps:

the method comprises the following steps: weighing a TPU material, a nylon elastomer, a modified graphene/chitosan intercalated montmorillonite antibacterial agent, stearic acid and a dicumyl peroxide crosslinking agent in a mass ratio of 2: 3, 2-oxo-diethyl malonate and ethylene glycol diethyl ether diamine tetraacetic acid blending agent for standby;

step two: the preparation method comprises the following steps of (1) mixing a TPU material, a nylon elastomer, a modified graphene/chitosan intercalated montmorillonite antibacterial agent, stearic acid and a dicumyl peroxide crosslinking agent in a mass ratio of 2: 3, sequentially adding the diethyl 2-oxomalonate and the ethylene glycol diethyl ether diamine tetraacetic acid blending agent into a high-speed mixer, and mixing at a high speed to obtain a premix;

step three: adding the premix obtained in the step two into a double-screw extruder, and injecting supercritical CO₂The high-resilience antibacterial TPU foaming material is obtained through the working procedures of shearing and mixing, pressure reduction and extrusion, temperature rise and foaming, cooling and shaping and the like.

Example 4:

a high-resilience antibacterial TPU (thermoplastic polyurethane) foaming material is composed of the following raw materials in parts by weight:

TPU material: 100 parts of (A);

nylon elastomer: 20 parts of (1);

modified graphene/chitosan intercalated montmorillonite antibacterial agent: 2 parts of (1);

stearic acid: 1.5 parts;

dicumyl peroxide crosslinking agent: 2 parts of (1);

the mass ratio is 2: 3 diethyl 2-oxopropanedioate and ethylene glycol diethyl ether diamine tetraacetic acid conditioner: 3.5 parts.

The modified graphene/chitosan intercalated montmorillonite antibacterial agent is prepared by the following method:

(1) preparation of modified graphene

Preparing graphene oxide by adopting an improved Hummers method, weighing 20g of graphene oxide, adding the graphene oxide into a three-neck flask filled with 100mL of ethanol, adding 1g of silane coupling agent while stirring, reacting for 4h at the temperature of 60 ℃, performing suction filtration, and drying to obtain the modified graphene.

(2) Preparation of modified graphene/chitosan

Accurately weighing 5g of chitosan, adding 200mL of deionized water, stirring, slowly dripping 50g of 20% acetic acid solution, and fully stirring for 5h to obtain the chitosan solution. Weighing 5g of the modified graphene prepared in the step (1), slowly adding the modified graphene into the chitosan solution, fully stirring to obtain a uniformly mixed modified graphene/chitosan solution, putting the solution into a vacuum oven, and carrying out vacuum drying at 85 ℃ to obtain the modified graphene/chitosan material.

(3) Preparation of modified graphene/chitosan intercalated montmorillonite antibacterial agent

Weighing 20g of montmorillonite, adding 600mL of deionized water, stirring and dispersing uniformly at normal temperature, slowly adding 40g of diethylenetriamine intercalating agent while stirring, fully reacting for 6h, then carrying out ultrasonic treatment for 100min to obtain a pre-intercalated montmorillonite suspension, weighing 5g of the modified graphene/chitosan material prepared in the step (2), adding the modified graphene/chitosan material into the pre-intercalated montmorillonite suspension, heating to 80 ℃, rapidly and mechanically stirring for 24h to obtain a modified graphene/chitosan intercalated montmorillonite suspension, and filtering, washing and drying to obtain the modified graphene/chitosan intercalated montmorillonite antibacterial agent.

The preparation method of the high-resilience antibacterial TPU foaming material comprises the following steps:

the method comprises the following steps: weighing a TPU material, a nylon elastomer, a modified graphene/chitosan intercalated montmorillonite antibacterial agent, stearic acid and a dicumyl peroxide crosslinking agent in a mass ratio of 2: 3, 2-oxo-diethyl malonate and ethylene glycol diethyl ether diamine tetraacetic acid blending agent for standby;

step two: the preparation method comprises the following steps of (1) mixing a TPU material, a nylon elastomer, a modified graphene/chitosan intercalated montmorillonite antibacterial agent, stearic acid and a dicumyl peroxide crosslinking agent in a mass ratio of 2: 3, sequentially adding the diethyl 2-oxomalonate and the ethylene glycol diethyl ether diamine tetraacetic acid blending agent into a high-speed mixer, and mixing at a high speed to obtain a premix;

step three: and (3) adding the premix obtained in the step two into a double-screw extruder, and performing procedures such as injecting supercritical CO2, shearing and mixing, depressurizing and extruding, heating for foaming, cooling for shaping and the like to obtain the high-resilience antibacterial TPU foaming material.

Comparative example 1:

a high-resilience antibacterial TPU (thermoplastic polyurethane) foaming material is composed of the following raw materials in parts by weight:

TPU material: 100 parts of (A);

nylon elastomer: 20 parts of (1);

modified graphene antibacterial agent: 2 parts of (1);

stearic acid: 1.5 parts;

dicumyl peroxide crosslinking agent: 2 parts of (1);

the mass ratio is 2: 3 diethyl 2-oxopropanedioate and ethylene glycol diethyl ether diamine tetraacetic acid conditioner: 3.5 parts.

The modified graphene antibacterial agent is prepared by the following method:

(1) preparation of modified graphene

Preparing graphene oxide by adopting an improved Hummers method, weighing 18g of graphene oxide, adding the graphene oxide into a three-neck flask filled with 100mL of ethanol, adding 0.8g of titanate coupling agent while stirring, reacting for 4 hours at the temperature of 50 ℃, performing suction filtration, and drying to obtain the modified graphene.

The preparation method of the high-resilience antibacterial TPU foaming material comprises the following steps:

the method comprises the following steps: weighing a TPU material, a nylon elastomer, a modified graphene antibacterial agent, stearic acid and a dicumyl peroxide crosslinking agent in a mass ratio of 2: 3, 2-oxo-diethyl malonate and ethylene glycol diethyl ether diamine tetraacetic acid blending agent for standby;

step two: the preparation method comprises the following steps of (1) mixing a TPU material, a nylon elastomer, a modified graphene antibacterial agent, stearic acid and a dicumyl peroxide crosslinking agent in a mass ratio of 2: 3, sequentially adding the diethyl 2-oxomalonate and the ethylene glycol diethyl ether diamine tetraacetic acid blending agent into a high-speed mixer, and mixing at a high speed to obtain a premix;

step three: adding the premix obtained in the step two into a double-screw extruder, and injecting supercritical CO₂The high-resilience antibacterial TPU foaming material is obtained through the working procedures of shearing and mixing, pressure reduction and extrusion, temperature rise and foaming, cooling and shaping and the like.

Comparative example 2:

a high-resilience antibacterial TPU (thermoplastic polyurethane) foaming material is composed of the following raw materials in parts by weight:

TPU material: 100 parts of (A);

nylon elastomer: 20 parts of (1);

chitosan antibacterial agent: 2 parts of (1);

stearic acid: 1.5 parts;

dicumyl peroxide crosslinking agent: 2 parts of (1);

the mass ratio is 2: 3 diethyl 2-oxopropanedioate and ethylene glycol diethyl ether diamine tetraacetic acid conditioner: 3.5 parts.

The preparation method of the high-resilience antibacterial TPU foaming material comprises the following steps:

the method comprises the following steps: weighing a TPU material, a nylon elastomer, a chitosan antibacterial agent, stearic acid and a dicumyl peroxide crosslinking agent in a mass ratio of 2: 3, 2-oxo-diethyl malonate and ethylene glycol diethyl ether diamine tetraacetic acid blending agent for standby;

step two: the preparation method comprises the following steps of (1) mixing a TPU material, a nylon elastomer, a chitosan antibacterial agent, stearic acid and a dicumyl peroxide crosslinking agent in a mass ratio of 2: 3, sequentially adding the diethyl 2-oxomalonate and the ethylene glycol diethyl ether diamine tetraacetic acid blending agent into a high-speed mixer, and mixing at a high speed to obtain a premix;

step three: adding the premix obtained in the step two into a double-screw extruder, and injecting supercritical CO₂The high-resilience antibacterial TPU foaming material is obtained through the working procedures of shearing and mixing, pressure reduction and extrusion, temperature rise and foaming, cooling and shaping and the like.

Comparative example 3:

the bacteriostatic TPU foaming material is prepared from the following raw materials in parts by weight:

TPU material: 100 parts of (A);

modified graphene/chitosan intercalated montmorillonite antibacterial agent: 2 parts of (1);

stearic acid: 1.5 parts;

dicumyl peroxide crosslinking agent: 2 parts of (1);

the mass ratio is 2: 3 diethyl 2-oxopropanedioate and ethylene glycol diethyl ether diamine tetraacetic acid conditioner: 3.5 parts.

The modified graphene/chitosan intercalated montmorillonite antibacterial agent is prepared by the following method:

(1) preparation of modified graphene

Preparing graphene oxide by adopting an improved Hummers method, weighing 18g of graphene oxide, adding the graphene oxide into a three-neck flask filled with 100mL of ethanol, adding 0.8g of titanate coupling agent while stirring, reacting for 4 hours at the temperature of 50 ℃, performing suction filtration, and drying to obtain the modified graphene.

(2) Preparation of modified graphene/chitosan

Accurately weighing 4.5g of chitosan, adding 200mL of deionized water, stirring, slowly dripping 45g of 17% acetic acid solution, and fully stirring for 4.5h to obtain the chitosan solution. Weighing 4g of the modified graphene prepared in the step (1), slowly adding the modified graphene into the chitosan solution, fully stirring to obtain a uniformly mixed modified graphene/chitosan solution, putting the solution into a vacuum oven, and carrying out vacuum drying at 85 ℃ to obtain the modified graphene/chitosan material.

(3) Preparation of modified graphene/chitosan intercalated montmorillonite antibacterial agent

Weighing 18g of montmorillonite, adding 600mL of deionized water, stirring and dispersing uniformly at normal temperature, slowly adding 35g of hexamethylenediamine intercalator while stirring, fully reacting for 5h, then carrying out ultrasonic treatment for 85min to obtain a pre-intercalated montmorillonite suspension, weighing 4g of the modified graphene/chitosan material prepared in the step (2), adding the modified graphene/chitosan material into the pre-intercalated montmorillonite suspension, heating to 75 ℃, rapidly and mechanically stirring for 20h to obtain a modified graphene/chitosan intercalated montmorillonite suspension, and filtering, washing and drying to obtain the modified graphene/chitosan intercalated montmorillonite antibacterial agent.

The preparation method of the antibacterial TPU foaming material comprises the following steps:

the method comprises the following steps: weighing a TPU material, a modified graphene/chitosan intercalated montmorillonite antibacterial agent, stearic acid and a dicumyl peroxide crosslinking agent in a mass ratio of 2: 3, 2-oxo-diethyl malonate and ethylene glycol diethyl ether diamine tetraacetic acid blending agent for standby;

step two: the preparation method comprises the following steps of (1) mixing a TPU material, a modified graphene/chitosan intercalated montmorillonite antibacterial agent, stearic acid and a dicumyl peroxide crosslinking agent in a mass ratio of 2: 3, sequentially adding the diethyl 2-oxomalonate and the ethylene glycol diethyl ether diamine tetraacetic acid blending agent into a high-speed mixer, and mixing at a high speed to obtain a premix;

step three: adding the premix obtained in the step two into a double-screw extruder, and injecting supercritical CO₂Shearing, mixing and extruding under reduced pressureAnd (3) performing the working procedures of discharging, heating for foaming, cooling for shaping and the like to obtain the high-resilience antibacterial TPU foaming material.

Test 1:

and (3) antibacterial property test: accurately weighing 0.1g of sample, adding into a triangular flask filled with 99mL of sterile water, and dispersing for 20min by ultrasonic waves. 1mL of bacterial suspension at a concentration of 107CFU/mL was added. Another flask containing 99mL of sterile water was used as a blank and 1mL of a suspension having a concentration of 107CFU/mL was added. Placing the triangular flask in a shaking incubator, and performing shaking culture at 37 deg.C and 200r/min for 30 min. 0.2mL of the mixed solution is taken from each triangular flask, diluted properly, coated on a culture dish, and cultured at the constant temperature of 35 ℃ for 48-72 h, and then colony counting is carried out. The two groups of samples are respectively subjected to 3 parallel experiments, and the antibacterial rate is calculated according to the following formula: r ═ [ (A-B)/A ]. times 100%

R is the antibacterial rate of the bacteria, namely,

a-average colony number of blank control group;

b-average colony number of the added antibacterial sample to be tested.

Staphylococcus aureus and Escherichia coli were selected for selection of the strain.

And (3) testing 2:

and (3) testing the resilience performance: the rebound resilience of the above examples and comparative examples was measured by GB/T6670-.

Table 1: antibacterial property and resilience test

Test items	anti-Staphylococcus aureus (%)	anti-Escherichia coli (%)	Rebound resilience (%)
				Example 1	91	90	51
Example 2	93	92	56
				Example 3	96	96	55
Example 4	95	96	57
				Comparative example 1	85	83	51
Comparative example 2	80	81	50
				Comparative example 3	96	95	41

From the test results in the table above, it can be found that, compared with the antibacterial agents graphene (comparative example 1) and chitosan (comparative example 2) with single component, the antibacterial effect of the novel modified antibacterial agent prepared by using the modified graphene/chitosan intercalated montmorillonite is obviously improved, under the condition of the same amount of antibacterial agent, the anti-staphylococcus aureus effect is improved from 80% to 95%, and the anti-escherichia coli effect is similarly improved. The novel antibacterial agent realizes the ordered intercalation of the graphene/chitosan composite antibacterial agent in the montmorillonite, effectively enhances the thermal stability of the antibacterial agent, and solves the problems of failure of the antibacterial agent caused by high temperature in the material processing process and the like. Meanwhile, the antibacterial agent is intercalated into the montmorillonite by utilizing an intercalation technology, so that the migration speed of the antibacterial agent can be effectively reduced, the dispersibility of the antibacterial agent in the matrix resin can be effectively improved, and the problem that the performance of the material is influenced because the graphene or chitosan single-component antibacterial agent is poor in dispersibility in the matrix resin and is easy to agglomerate is solved.

The addition of the nylon elastomer can effectively reduce the influence of the addition of the inorganic antibacterial agent on the elastic performance of the foaming material. As can be seen from table 1, the resilience of comparative example 3 without adding nylon elastomer is 41%, which is significantly reduced compared to comparative example 1 (51%) and comparative example 2 (50%), while the resilience of examples 1, 2, 3, and 4 is increased to about 55% by adding nylon elastomer, so that the antibacterial property of the material is improved and the elastic property of the material is effectively maintained and improved.

The above description is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above embodiments, and all technical solutions belonging to the idea of the present invention belong to the protection scope of the present invention. It should be noted that modifications and embellishments within the scope of the invention may occur to those skilled in the art without departing from the principle of the invention, and are considered to be within the scope of the invention.