CN115946430B

CN115946430B - Preparation process of waterproof antibacterial composite fiber fabric for medical product

Info

Publication number: CN115946430B
Application number: CN202310229848.0A
Authority: CN
Inventors: 张宝根
Original assignee: Silk Dragon Biotechnology Co ltd
Current assignee: Silk Dragon Biotechnology Co ltd
Priority date: 2023-03-10
Filing date: 2023-03-10
Publication date: 2023-06-27
Anticipated expiration: 2043-03-10
Also published as: CN115946430A

Abstract

A preparation process of waterproof antibacterial composite fiber fabric for medical products comprises the following steps: s1: spinning China hemp fiber, viscose fiber and PLA fiber to obtain base cloth; s2: immersing the base cloth into the antibacterial finishing liquid, wherein one part of the base cloth is used as an antibacterial inner base cloth, and the other part of the base cloth is used as a waterproof antibacterial outer base cloth semi-finished product; s3: scraping the waterproof finishing liquid on a waterproof antibacterial outer layer base fabric semi-finished product through a film coater to form a waterproof film layer serving as the waterproof antibacterial outer layer base fabric; s4: and spinning on the antibacterial inner layer base cloth through an electrostatic spinning machine to obtain the heat-conducting composite fiber membrane. The preparation process of the waterproof antibacterial composite fiber fabric for the medical product has the advantages that the prepared composite fiber fabric has a three-layer structure of antibacterial inner-layer base fabric, heat-conducting composite fiber membrane and waterproof antibacterial outer-layer base fabric, waterproof, antibacterial and heat-conducting properties are improved under the conditions of ensuring high protection and moisture permeability and air permeability, and the waterproof antibacterial composite fiber fabric has the advantages of high protection safety, good heat and moisture comfort and biodegradability.

Description

Preparation process of waterproof antibacterial composite fiber fabric for medical product

Technical Field

The invention belongs to the technical field of composite fiber fabrics, and particularly relates to a preparation process of a waterproof antibacterial composite fiber fabric for medical products.

Background

With the extremely rapid increase of the demand of medical protection products, the production and use of fabrics for medical products are greatly increased. At present, the fabric for medical products has the following problems to be solved urgently: 1. in order to achieve better barrier performance, most of the fabric for medical products contains non-degradable polymer materials, and has great environmental pollution; 2. the waterproof performance and the moisture permeability cannot be combined, and long-time wearing can influence the delivery of hot water vapor in the sweating period of a wearer, so that the heat load is caused; 3. when the fabric for medical products is worn, if germs are easy to carry on the surface of the fabric, the fabric needs to be replaced frequently, so that waste is caused; 4. after the fabric for medical products is worn for a long time, the loss and the generation of heat of a human body cannot reach balance, the heat in the body of a wearer cannot be normally emitted, so that the thermal fatigue is caused, and strong sultry feeling can be generated under high-strength work, so that the discomfort of the body is caused.

The Chinese patent application number CN202210928277.5 discloses an antibacterial ultraviolet-proof high-efficiency low-resistance micro-nanofiber mask fabric and a preparation method thereof, wherein the antibacterial ultraviolet-proof high-efficiency low-resistance micro-nanofiber mask fabric is of a sandwich structure and comprises an inner layer, an intermediate layer and an outer layer; the inner layer is a hydrophilic layer, the middle layer is a nanofiber membrane containing a photocatalytic composite antibacterial agent, and the outer layer is a hydrophobic layer. The PP spun-bonded non-woven fabric-nanofiber membrane prepared by electrostatic spinning is used as an outer layer and an intermediate layer respectively, viscose spun-bonded non-woven fabric is covered as an inner layer, nano-scale Ag, GO or nonmetal ion doped photocatalytic antibacterial agent is used for improving antibacterial performance, and hydrophobic PP spun-bonded non-woven fabric is used as an outer layer for improving waterproof performance. The patent does not solve the problems of environmental pollution caused by the fact that the fabric for medical products contains non-degradable components, and the problems that the waterproof property and the moisture permeability cannot be considered and the heat cannot be normally emitted after being worn for a long time.

Therefore, the invention aims to develop a preparation process of the composite fiber fabric for medical products, and the composite fiber fabric prepared by adopting the preparation process has the characteristics of water resistance, antibiosis, heat conduction, good heat and moisture comfort and biodegradability.

In addition, many fabrics for medical products comprise non-woven fabrics, in particular to non-woven fabrics by a water jet method, the water jet process is adopted, the speed is high, only 5 minutes are needed from fibers to the non-woven fabrics, links such as spinning, spooling and warping weaving in traditional spinning are omitted, the working hours are greatly shortened, the energy consumption and the labor cost are saved, the cost can be reduced by 30%, and the production process is environment-friendly and pollution-free. However, the water consumption of the nonwoven fabric processed by the hydroentangling machine is large and varies from 50 to 500t/h, and the water consumption of the nonwoven fabric processed by the hydroentangling machine may produce fiber oil, various fiber flocks, and foreign matters such as microfibrils separated from the fibers, cellulose aggregates, and the like. Therefore, if it cannot be used up, it will cause a great waste. However, if the water is improperly treated, the quality of the product is directly affected, and even the hydroentangler cannot normally operate. For example, the foreign matter and dirt may clog needle holes of the water needle plate to affect product quality, and may also cause deformation of the needle plate.

Therefore, another object of the invention is to develop a device for treating and utilizing the water thorn machine backwater in the preparation process of the composite fiber fabric for medical products, which improves the recovery and utilization rate of the water thorn backwater, reduces the cost and avoids the waste of water resources.

Disclosure of Invention

The invention aims to: in order to overcome the defects, the invention aims to provide a preparation process of waterproof antibacterial composite fiber fabric for medical products, which is reasonable in process step design, and the prepared composite fiber fabric has a three-layer structure of antibacterial inner-layer base fabric, heat-conducting composite fiber membrane and waterproof antibacterial outer-layer base fabric, and has the advantages of high protection safety, good heat and moisture comfort, biodegradability and wide application prospect, and waterproof, antibacterial and heat-conducting performances are improved under the condition of ensuring high protection and moisture permeability.

The invention aims at realizing the following technical scheme:

a waterproof antibacterial composite fiber fabric for medical products comprises the following steps:

s1: the hemp fiber, viscose fiber and PLA fiber are mixed according to the proportion of 4 to 6:2-3: mixing the materials according to the mass ratio of 1-3, opening the materials by an opener and carding the materials by a carding machine to obtain a fiber web, reinforcing the fiber web by a hydroentangled machine to obtain a base fabric, and naturally airing the base fabric for later use;

S2: immersing the base cloth into the antibacterial finishing liquid for 0.5-2h, baking for 1-5min, naturally airing, wherein one part of the base cloth is used as an antibacterial inner base cloth, and the other part of the base cloth is used as a waterproof antibacterial outer base cloth semi-finished product; the antibacterial finishing liquid comprises the following components: 120-130g/L of 2D resin and 50-60g/L, mgCl of antibacterial microcapsule ₂ 10-20g/L, JFC penetrating agent 0.5-1.5g/L;

s3: scraping the waterproof finishing liquid on a semi-finished waterproof and antibacterial outer-layer base fabric product through a film coater to form a waterproof film layer with the thickness of 50-500 mu m, naturally placing for 1-2h, then soaking in a pure water gel bath, soaking for 12-24h at room temperature, and naturally airing to obtain the waterproof and antibacterial outer-layer base fabric; the waterproof finishing liquid comprises the following raw materials in parts by weight: 90-100 parts of poly (adipic acid)/butylene terephthalate solution, 0.5-2 parts of azodicarbonamide and 0.1-0.5 part of ZnO; the poly (adipic acid)/butylene terephthalate solution is prepared by dissolving poly (adipic acid)/butylene terephthalate in DMF (dimethyl formamide) and has a solid content of 10-30%;

s4: PLA, PCL and heat conducting particles are mixed according to 80-90:8-12:2-4, dissolving in a solvent, continuously stirring at 70-80 ℃ for 5-6 hours to prepare a heat conduction spinning solution with the concentration of 5-15wt%, coating the antibacterial inner layer base cloth on a roller for a week, carrying out ultrasonic treatment on the heat conduction spinning solution for 10-30 minutes, and spinning on the antibacterial inner layer base cloth of the roller by an electrostatic spinning machine to obtain a heat conduction composite fiber membrane;

S5: the waterproof antibacterial outer layer base cloth and the antibacterial inner layer base cloth covered with the heat-conducting composite fiber membrane are compounded into a whole through a hot roller hot press, and the waterproof membrane layer of the waterproof antibacterial outer layer base cloth is arranged outwards.

The preparation process of the waterproof antibacterial composite fiber fabric for the medical product is reasonable in design, the degradable materials such as the China-hemp fiber, the viscose fiber and the PLA fiber are used as raw materials, the base fabric is prepared by a water-jet method, the China-hemp fiber has good moisture absorption and air permeability, and also has certain natural functionality (such as antibacterial and ultraviolet resistance), but the China-hemp fiber has a plurality of hairiness, is hard and long, is added with impurities such as pectin and lignin in the China-hemp fiber, and has poor spinnability, the problem that the China-hemp fiber is difficult to tangle and cohesive can be solved by adding the slender and soft viscose fiber, the PLA fiber has good oxygen permeability, high barrier property and biocompatibility to smell and certain antibacterial and mildew inhibition property, and the hot-melt fiber PLA can be melted under the subsequent hot rolling condition to solidify the China-hemp fiber, the viscose fiber and the heat-conducting composite fiber film, so that a more stable structure is formed.

Then, microcapsule antibacterial finishing is carried out on the base fabric, and the base fabric is subjected to crosslinking action of 2D resin, permeation action of JFC permeation agent and MgCl ₂ Under the catalysis of the catalyst, the antibacterial finishing liquid can permeate between the base fabric fiber and the antibacterial microcapsule in the impregnation process, and through forming chemical bonds and hydrogen bonds with active groups on the wall of the antibacterial microcapsule and the base fabric fiber, the antibacterial microcapsule is stably and uniformly distributed and fixed on the base fabric, the slow release performance of the antibacterial microcapsule can enable the antibacterial agent embedded in the antibacterial microcapsule to be slowly released, the antibacterial performance of the base fabric is longer and lasting, meanwhile, the antibacterial agent embedded in the antibacterial microcapsule can be protected, and the use value of the antibacterial agent is improved.

Then, one part of the base cloth after the microcapsule antibacterial finishing is used as an antibacterial inner layer base cloth, the other part of the base cloth is used as a waterproof antibacterial outer layer base cloth semi-finished product, one surface of the waterproof antibacterial outer layer base cloth semi-finished product facing outwards is subjected to waterproof finishing, a film forming method is adopted, poly (adipic acid)/butylene terephthalate) is dissolved in DMF (dimethyl formamide) solvent, azodicarbonamide and ZnO are added to prepare waterproof finishing liquid, the poly (adipic acid)/butylene terephthalate) has good water vapor permeability, breaking strength, breaking elongation and biodegradability, the waterproof finishing liquid is scraped on the waterproof antibacterial outer layer base cloth semi-finished product through a film coater, the waterproof finishing liquid is soaked in a pure water gel bath, the DMF solvent is evaporated and dried, and the waterproof finishing liquid is solidified into a waterproof film layer with the aperture of 85-95 mu m under the pore-forming nucleation action of the azodicarbonamide and the activation action of ZnO, and the waterproof antibacterial outer layer base cloth has excellent waterproof air permeability due to the fact that the pore diameter is between water vapor molecules and liquid water drop molecules and the dispersibility of pores is good.

Finally, a heat-conducting composite fiber membrane is arranged between the antibacterial inner-layer base cloth and the waterproof antibacterial outer-layer base cloth, the heat-conducting composite fiber membrane takes degradable materials such as PLA and PCL as raw materials, heat-conducting particles are doped, the heat-conducting particles are uniformly loaded on the heat-conducting composite fiber membrane through an electrostatic spinning technology and are internally constructed to interconnect a heat-conducting frame, brittleness can be improved by mixing the PLA and the PCL, the heat-conducting composite fiber membrane not only serves as an adhesive layer between the antibacterial inner-layer base cloth and the waterproof antibacterial outer-layer base cloth (the PLA and the PCL can be melted under the hot rolling pressure condition), but also serves as a heat-conducting layer to improve the heat transfer performance of the composite fiber fabric, and the heat-conducting mode enables the composite fiber fabric to produce a cooling effect, so that the hot wet comfort of a user is improved.

In summary, the composite fiber fabric prepared by the preparation process has the three-layer structure of the antibacterial inner-layer base fabric, the heat-conducting composite fiber film and the waterproof antibacterial outer-layer base fabric, and the PLA and PCL bonding effect of the antibacterial inner-layer base fabric, the heat-conducting composite fiber film and the waterproof antibacterial outer-layer base fabric can reduce the problems of easy separation between layers and poor mechanical property of the composite fiber fabric, increases the waterproof, antibacterial and heat-conducting properties under the conditions of ensuring high protection, moisture permeability and air permeability, has the advantages of high protection safety, good heat-moisture comfort and biodegradability, and is suitable for medical products.

Further, the preparation process of the waterproof and antibacterial composite fiber fabric for medical products comprises the following steps:

antibacterial inner layer base cloth;

waterproof antibacterial outer layer base cloth;

the heat-conducting composite fiber membrane, the antibacterial inner layer base cloth, the heat-conducting composite fiber membrane and the waterproof antibacterial outer layer base cloth are sequentially arranged in a laminated mode and are combined into a whole through hot pressing.

Preferably, the antibacterial inner layer base fabric comprises a single layer base fabric, or comprises a plurality of layers of base fabric, and the layers of base fabric are laminated and hot-pressed into a whole and then are processed by S2.

Preferably, the waterproof antibacterial outer-layer base fabric also comprises a single-layer base fabric, or comprises a plurality of layers of base fabrics, and the layers of base fabrics are laminated and are combined into a whole through hot pressing, and then are processed through S2 and S3.

The filter efficiency of the base cloth on the tiny particles can be obviously improved by increasing the number of layers of the base cloth. Wherein, the single-layer base cloth (the surface density of the base cloth is 50-100 g/m) has the filtering efficiency of 30-50% on the particles with the size of 2.5 mu m at the wind speed of 40 cm/s. The filtering efficiency of the 3-layer base cloth for the particles with the size of 2.5 mu m at the wind speed of 40cm/s can reach more than 99 percent, and the mechanical property is not changed obviously. The number of layers of the base fabric is selected as desired by those skilled in the art.

Further, in the preparation process of the waterproof antibacterial composite fiber fabric for the medical product, in the step S2, the base fabric is immersed into the antibacterial finishing liquid, and the bath ratio is 1:20-40, soaking at 30-50deg.C, baking at 50-70deg.C for 1-5 min; the antibacterial microcapsules in the antibacterial finishing liquid are of spherical structures, and the average particle size is 1-5 mu m; the antibacterial microcapsule comprises a wall material and a core material, wherein the wall material is sodium alginate and chitosan quaternary ammonium salt, the core material is an antibacterial agent, and the wall material wraps the core material.

The sodium alginate is an anionic polymer, the chitosan quaternary ammonium salt is a cationic polymer, the oppositely charged sodium alginate and the chitosan quaternary ammonium salt are flocculated through electrostatic interaction, phase separation occurs, the core antibacterial agent is embedded by the gelation and solidification of a coacervate, so that the antibacterial agent is microencapsulated, and a good slow release effect is obtained.

Further, the preparation process of the waterproof antibacterial composite fiber fabric for medical products comprises the following steps of:

(1) Respectively preparing 1-3% sodium alginate aqueous solution, 0.5-1% chitosan quaternary ammonium salt aqueous solution and 3-8% calcium chloride solution;

(2) Adding tween-80 emulsifier into the sodium alginate aqueous solution, wherein the addition amount of the tween-80 emulsifier is 0.5-2% of the volume of the sodium alginate aqueous solution, and uniformly stirring, and then according to the core-wall ratio of 1-3:1-3 adding an antibacterial agent to obtain an antibacterial solution, and shearing the antibacterial solution at a speed of 10000-12000r/min for 5-15min to obtain an antibacterial agent/sodium alginate emulsion with an oil-in-water structure;

(3) Taking chitosan quaternary ammonium salt aqueous solution with the volume of 2-4 times of that of the sodium alginate aqueous solution, slowly dripping an antibacterial agent/sodium alginate emulsion into the chitosan quaternary ammonium salt aqueous solution, stirring at the speed of 1200-1500r/min, adjusting the pH value to 5-6 after dripping, continuously stirring at the speed of 1200-1500r/min, and stirring for 20-30min to obtain the antibacterial agent/sodium alginate emulsion/chitosan quaternary ammonium salt emulsion;

(4) Slowly dropwise adding a calcium chloride solution into the antibacterial agent/sodium alginate emulsion/chitosan quaternary ammonium salt emulsion, wherein the addition amount of the calcium chloride solution is 30-50% of the volume of the sodium alginate aqueous solution, and reacting for 2-3h in a water bath at 30-60 ℃ to obtain an antibacterial microcapsule suspension;

(5) And centrifugally washing the antibacterial microcapsule suspension for 3-5 times, and freeze-drying for 12 hours to obtain the antibacterial microcapsule.

The reaction process for preparing the antibacterial microcapsule is mild, the characteristic of the antibacterial agent can be well protected, the stability is good, the loading capacity and the encapsulation rate are high, the antibacterial agent/sodium alginate emulsion is fully emulsified and dispersed to obtain an oil-in-water structure, the chitosan quaternary ammonium salt aqueous solution with opposite charges is added to generate flocculation, and the calcium chloride solution Ca is dropwise added ²⁺ Ion exchange with sodium alginate to make it cross-link and complex, quicken the gelation and solidification of coacervate, centrifugal washing and freeze drying to obtain the invented antibacterial microcapsule.

Preferably, in the step S3, the fabric is soaked in pure water gel bath for 6-8 hours at room temperature, then taken out, replaced by new pure water gel bath, further soaked for 6-8 hours, taken out, and placed in room temperature dust-free air for natural airing to serve as the waterproof antibacterial outer layer base fabric for later use.

Further, in the preparation process of the waterproof antibacterial composite fiber fabric for the medical product, the antibacterial agent is one or a combination of more of thymol, oregano oil, mugwort oil, carvacrol, weeping forsythiae oil, citronella oil and mugwort essential oil; the heat conducting particles are dopamine modified boron nitride.

The antibacterial agent is a natural antibacterial substance, is safe and nontoxic, and has good biocompatibility and high antibacterial efficiency. The dopamine modified boron nitride is prepared by carrying out surface modification on hexagonal boron nitride through the oxidation self-polymerization characteristic of dopamine, so that a compact coating film is formed on the surface of hexagonal boron nitride by polydopamine, and active groups are introduced, so that the interface combination among PLA, PCL and heat conducting particles can be improved, and the heat conducting property of the heat conducting composite fiber film is improved. The chemical formula of the dopamine-modified boron nitride is as follows:

。

In the S4, spraying a layer of PCL adhesive film on one side of the antibacterial inner layer base cloth, coating the antibacterial inner layer base cloth on a circle of a roller, arranging one side of the PCL adhesive film outwards, performing ultrasonic treatment on a heat-conducting spinning solution for 10-30min, and spinning on the antibacterial inner layer base cloth coated with the PCL adhesive film by an electrostatic spinning machine to obtain a heat-conducting composite fiber film; in the step S5, a PCL adhesive film is sprayed on one surface of the waterproof antibacterial outer layer base cloth in the direction opposite to the waterproof film layer, the waterproof antibacterial outer layer base cloth and the antibacterial inner layer base cloth covered with the heat-conducting composite fiber film are compounded into a whole through a hot roller hot press, and the waterproof film layer of the waterproof antibacterial outer layer base cloth is arranged outwards.

By arranging the PCL adhesive film layer between the antibacterial inner layer base cloth and the heat-conducting composite fiber film and between the heat-conducting composite fiber film and the waterproof antibacterial outer layer base cloth, the problems of easy separation between layers and poor mechanical property of the composite fabric can be further reduced.

Further, in the preparation process of the waterproof antibacterial composite fiber fabric for medical products, in the step S4, parameters of the electrostatic spinning machine are set as follows: positive voltage 20-30 KV, negative voltage 1-5KV, push injection speed of heat conduction spinning solution 0.05-0.2mm/min, needle-to-drum distance fixed at 10-30cm, translation speed of electrostatic spinning machine at 300-600mm/min, and received drum rotation speed at 100-200rpm/min; in the step S5, parameters of the hot roll hot press are set as follows: the heat rolling laminating speed is 1-5r/min, and the heat treatment temperature is 80-100 ℃.

The heat-conducting composite fiber membrane with the nanofiber structure can be obtained through electrostatic spinning, so that better air permeability and water vapor transmittance are provided. The antibacterial inner base cloth, the waterproof antibacterial outer base cloth and the PLA and PCL of the heat-conducting composite fiber film are melted by heating and pressurizing of hot rolling and hot pressing, and the antibacterial inner base cloth, the waterproof antibacterial outer base cloth and the heat-conducting composite fiber film are solidified to form a more stable structure.

The invention also relates to a hydroentangling machine of S1 in the preparation process of the waterproof antibacterial composite fiber fabric for medical products, which comprises the following steps:

the hydroentangling mechanism comprises a net curtain, a plurality of guide rollers, a plurality of hydroentangling heads and a plurality of negative pressure suction dehydrators; the net curtain is of an annular structure, is sleeved on the guide rollers, and forms annular conveying of the net curtain through rotation of the guide rollers so as to support the fiber net; a plurality of water thorn heads are uniformly distributed above the net curtain, a plurality of negative pressure suction dehydrators are uniformly distributed below the net curtain, and the water thorn heads and the negative pressure suction dehydrators are correspondingly arranged up and down;

the water thorn return water treatment mechanism comprises a gas-water separator, a return water collecting tank, a sand filter group, a clean water tank, a metal filter and a high-pressure pump, wherein the outlet of the negative pressure suction dehydrator, the gas-water separator, the return water collecting tank, the sand filter group, the clean water tank, the metal filter, the high-pressure pump and the inlet of the water thorn head are sequentially connected through pipelines.

The working principle of the hydro-entangled mechanism is as follows: the web curtain and a plurality of guide rollers support the fiber web to move, high-pressure water flow pressurized by the high-pressure pump continuously sprays the fiber web below from the water jet head, and fibers in the fiber web are enabled to move, displace and rearrange and intertwine under the impact of the water needle, so that the fiber web is reinforced. The retained water in the fiber net is sucked through a plurality of negative pressure suction dehydrators in the hydroentanglement process, so that the influence on the fiber entanglement effect in the subsequent hydroentanglement process can be avoided, and the subsequent drying of the fiber net is facilitated.

The water consumption of the hydro-entangled mechanism is very large and is generally between 50 and 500t/h, if the hydro-entangled mechanism cannot be utilized, the hydro-entangled mechanism can cause great waste, but the water after the hydro-entangled process contains fiber oiling agents, various fiber short scraps, micro-fibrils separated from fibers, cellulose aggregates and other impurities, and if the water returns to the hydro-entangled head without treatment, the hydro-entangled head is blocked by a hydro-entangled needle plate, the needle holes of the hydro-entangled head are worn and deformed, and the quality of a fiber web is influenced. By arranging the water-jet backwater treatment mechanism, the sand filter group-metal filter water treatment method is adopted, and the sand filter group is used for mechanically separating, adsorbing and contacting the impurities in the water after the water-jet process, so that the cost is low, and the recycling rate of the water-jet process water is increased.

Preferably, a plurality of metal filter screens are detachably arranged in the metal filter, so that later cleaning and replacement are facilitated.

Further, the water thorn machine of S1 in the preparation technology of the waterproof antibacterial composite fiber fabric for medical products, the sand filter group comprises:

the sand filter is of a double-chamber structure and comprises 2 sand filter chambers, wherein a filter material layer body, a padding layer body and a drainage system are arranged in each sand filter chamber from top to bottom; the backwater collecting tank, the sand filtering chamber and the clean water tank are sequentially connected through pipelines;

and the sand filter tank, the back flush sedimentation tank and the backwater collecting tank are sequentially connected through pipelines.

The sand filter group comprises a sand filter and a back flushing sedimentation tank, so that the two processes of filtering and back flushing can be alternately performed, the filtering period of the sand filter can be prolonged, and the subsequent maintenance cost is reduced.

The sand filter adopts a double-chamber structure, and comprises 2 sand filter chambers, when in back flushing, one sand filter chamber can be back flushed, and the other sand filter chamber can be continuously used for filtering, so that the sand filter chambers can continuously work.

Preferably, the filter material layer body in each sand filter chamber is filled with filter materials with the particle size of 0.5-10mm, the padding layer body is filled with padding with the particle size of 20-30mm, and the drainage system consists of drainage pipelines.

Further, the water thorn machine of S1 in the preparation technology of the waterproof antibacterial composite fiber fabric for medical products, the sand filter group further comprises:

the water inlet pipe is provided with a water inlet valve;

a water inlet channel;

the water inlet of the backwater collecting tank, the water inlet pipe, the water inlet channel, the water outlet tank and the sand filtering chamber are sequentially connected;

the water outlet of the sand filtering chamber, the water outlet pipe and the clean water tank are connected in sequence; the drain pipe is provided with a drain valve;

back flushing the water inlet pipe;

a back flush water outlet pipe, a back flush port of the sand filter chamber, a back flush water inlet pipe, a water discharge tank, a water inlet channel, a back flush water outlet pipe and a water inlet of a back flush sedimentation tank are sequentially connected; the back flush water inlet pipe is provided with a back flush water inlet valve, and the back flush water outlet pipe is provided with a back flush water washing valve.

Compared with the prior art, the invention has the following beneficial effects:

(1) The preparation process of the waterproof antibacterial composite fiber fabric for the medical product disclosed by the invention has reasonable process steps, the prepared composite fiber fabric has a three-layer structure of the antibacterial inner-layer base fabric, the heat-conducting composite fiber membrane and the waterproof antibacterial outer-layer base fabric, under the condition of ensuring high protection and moisture permeability and air permeability, the waterproof, antibacterial and heat-conducting properties are improved, the waterproof antibacterial composite fiber fabric has the advantages of high protection safety, good heat-moisture comfort and biodegradability, and the bonding effect of PLA and PCL contained in the antibacterial inner-layer base fabric, the heat-conducting composite fiber membrane and the waterproof antibacterial outer-layer base fabric can reduce the problems of easy separation between layers and poor mechanical property of the composite fiber fabric;

(2) The waterproof antibacterial composite fiber fabric for the medical product disclosed by the invention is prepared from degradable materials such as China-hemp fibers, viscose fibers and PLA fibers by a water-jet spinning method, and combines the advantages of the China-hemp fibers, the viscose fibers and the PLA fibers; the antibacterial microcapsule is stably uniformly distributed and fixed on the base cloth, and the slow release performance of the antibacterial microcapsule can enable the antibacterial agent embedded in the antibacterial microcapsule to be slowly released, so that the antibacterial performance of the base cloth is longer and lasting, and meanwhile, the antibacterial agent embedded in the antibacterial microcapsule can be protected; the waterproof and antibacterial outer layer base cloth is solidified into a waterproof membrane layer with the aperture of 85-95 mu m under the pore-forming nucleation action of azodicarbonamide and the activation action of ZnO, and the waterproof and antibacterial outer layer base cloth has excellent waterproof and breathable performance due to the fact that the aperture of the waterproof membrane layer is between the diameters of vapor molecules and liquid water drops and the dispersibility of pores is good;

(3) According to the preparation process of the waterproof antibacterial composite fiber fabric for the medical product, the heat-conducting composite fiber membrane is arranged between the antibacterial inner-layer base fabric and the waterproof antibacterial outer-layer base fabric, the heat-conducting composite fiber membrane takes degradable materials such as PLA and PCL as raw materials, heat-conducting particles are doped, the heat-conducting particles are uniformly loaded on the heat-conducting composite fiber membrane through an electrostatic spinning technology, an interconnection heat-conducting frame is built inside the heat-conducting composite fiber membrane, and the composite fiber fabric has a cooling effect in a heat conduction mode, so that the heat and humidity comfort of a user is improved;

(4) The invention discloses a preparation process of waterproof and antibacterial composite fiber fabric for medical products, which aims at the problem of recycling of water-jet backwater in the preparation process, a plurality of negative pressure suction dehydrators are used for sucking retained water in a fiber web in the water-jet process, so that the fiber entanglement effect in the subsequent water-jet process is avoided, the subsequent drying of the fiber web is facilitated, the water sucked by the negative pressure suction dehydrators is treated by a water-jet backwater treatment mechanism and then flows back to a water-jet head for recycling, the water-jet backwater treatment mechanism adopts a water treatment method of a sand filter group-metal filter, impurities in a water body are subjected to mechanical separation filtering, adsorption and contact coagulation by the sand filter group, and two processes of filtering and backwashing of the sand filter group can be alternately performed, so that the filtering period of the sand filter group is prolonged, the cost is low, and the recycling rate of water used in the water-jet process is improved.

Drawings

FIG. 1 is a schematic structural view of a waterproof and antibacterial composite fiber fabric for medical products according to the first embodiment of the invention;

fig. 2 is a schematic structural diagram II of the waterproof antibacterial composite fiber fabric for medical products;

FIG. 3 is an overall layout of a hydroentangling machine for S1 in the process of preparing the waterproof antimicrobial composite fiber fabric for medical products according to the present invention;

fig. 4 is a schematic connection diagram of a water-jet backwater treatment mechanism of the water-jet machine for S1 in the preparation process of the waterproof antibacterial composite fiber fabric for medical products according to the present invention;

FIG. 5 is a cross-sectional view of a sand filter group of the hydroentangling machine for S1 in the preparation process of the waterproof antibacterial composite fiber fabric for medical products according to the present invention;

FIG. 6 is a slow release profile of the antimicrobial microcapsules of examples 2-4 of the present invention;

in the figure: the water-proof antibacterial inner-layer base cloth 1, the water-proof antibacterial outer-layer base cloth 2, the waterproof film layer 21, the heat-conducting composite fiber film 3, the water thorn mechanism 4, the net curtain 41, the guide roller 42, the water thorn head 43, the negative pressure suction dehydrator 44, the water thorn backwater treatment mechanism 5, the gas-water separator 51, the backwater collecting tank 52, the sand filter group 53, the sand filter 531, the sand filter chamber 5311, the filter material layer 5312, the pad layer 5313, the drainage system 5314, the backwash sedimentation tank 532, the water inlet pipe 533, the water inlet channel 534, the drainage tank 535, the drainage pipe 536, the backwash water inlet pipe 537, the backwash water outlet 538, the clean water tank 54, the metal filter 55, the high-pressure pump 56, the PCL adhesive film a and the fiber net b.

Detailed Description

The following will clearly and completely describe the technical solutions in the examples of the present invention in combination with specific experimental data and fig. 1-6 in examples 1, 2-4, comparative examples 1 and 5, comparative examples 2-4 and examples 6-7, and examples 8-10, and it is apparent that the described examples are only some examples of the present invention, but not all examples. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to fall within the scope of the invention.

Example 1 below provides a base fabric and a process for preparing the same.

The fiber raw materials used in example 1 are all commercially available, and the specifications and properties are shown in Table 1.

TABLE 1 specification and Properties of fiber raw materials

Example 1

Hemp fiber, viscose fiber and PLA fiber are mixed according to a proportion of 50:35:15, and carding by an opener to obtain a fiber web, reinforcing the fiber web by a hydroentangler, and naturally airing to obtain the example 1.

The base fabric prepared in example 1 above was subjected to mechanical property test according to the following test method, and the test results are shown in table 2.

(1) Breaking strength and elongation at break: refer to GB/T24218.3-2010.

(2) Burst strength: refer to GB/T24218.5-2016.

(3) Tear strength: reference is made to FZ/T60006-91.

TABLE 2 mechanical test results of example 1

Examples 2-4 below provide a process for preparing an antimicrobial microcapsule and an antimicrobial inner base fabric.

Examples 2-4 used sodium alginate, chitosan quaternary ammonium salt, calcium chloride, tween-80 emulsifier, mugwort essential oil, mugwort oil, carvacrol, 2D resin, mgCl ₂ JFC penetrants are all commercially available.

Example 2

The preparation of the antimicrobial microcapsules of example 2 comprises the steps of:

(1) Respectively preparing 2% sodium alginate aqueous solution, 1% chitosan quaternary ammonium salt aqueous solution and 6% calcium chloride solution;

(2) Adding tween-80 emulsifier into the sodium alginate aqueous solution, wherein the addition amount of the tween-80 emulsifier is 1.2 percent of the volume of the sodium alginate aqueous solution, and uniformly stirring, and then according to the core-wall ratio of 1:1, adding an antibacterial agent, namely, mugwort essential oil to obtain an antibacterial liquid, and shearing the antibacterial liquid at a speed of 12000r/min for 10min to obtain mugwort essential oil/sodium alginate emulsion with an oil-in-water structure;

(3) Taking chitosan quaternary ammonium salt aqueous solution with the volume 3 times of that of the sodium alginate aqueous solution, slowly dripping the mugwort essential oil/sodium alginate emulsion into the chitosan quaternary ammonium salt aqueous solution, stirring at the speed of 1400r/min, adjusting the pH value to 5-6 after dripping, and continuously stirring at the speed of 1400r/min for 30min to obtain mugwort essential oil/sodium alginate emulsion/chitosan quaternary ammonium salt emulsion;

(4) Slowly dropwise adding a calcium chloride solution into the mugwort essential oil/sodium alginate emulsion/chitosan quaternary ammonium salt emulsion, wherein the addition amount of the calcium chloride solution is 35% of the volume of the sodium alginate aqueous solution, and reacting for 3 hours in a water bath at 40 ℃ to obtain an antibacterial microcapsule suspension;

(5) The above-mentioned antibacterial microcapsule suspension was centrifugally washed 3-5 times and freeze-dried for 12 hours to obtain the antibacterial microcapsule of example 2.

The preparation of the antibacterial inner layer base fabric of example 2 includes the following:

according to the antibacterial actionThe finishing liquid comprises: 2D resin 125 g/L, antimicrobial microcapsules 55g/L, mgCl of example 2 ₂ 15 An antibacterial finishing liquid was prepared by the formulation of g/L, JFC penetrant 1.0 g/L, and the base fabric of example 1 was immersed in the antibacterial finishing liquid with a bath ratio of 1:30, soaking at 40deg.C for 1.5. 1.5 h, baking at 60deg.C for 3 min, and naturally air-drying to obtain the antibacterial inner layer base fabric of example 2.

Example 3

The preparation of the antimicrobial microcapsules of example 3 comprises the steps of:

(1) Respectively preparing 1.5% sodium alginate aqueous solution, 0.75% chitosan quaternary ammonium salt aqueous solution and 5% calcium chloride solution;

(2) Adding tween-80 emulsifier into the sodium alginate aqueous solution, wherein the addition amount of the tween-80 emulsifier is 1% of the volume of the sodium alginate aqueous solution, and uniformly stirring the mixture according to the core-wall ratio of 1:2 adding an antibacterial agent mugwort oil to obtain an antibacterial liquid, and shearing the antibacterial liquid at a speed of 10000r/min for 15min to obtain a mugwort oil/sodium alginate emulsion with an oil-in-water structure;

(3) Taking chitosan quaternary ammonium salt aqueous solution with the volume 3 times of that of the sodium alginate aqueous solution, slowly dripping the mugwort oil/sodium alginate emulsion into the chitosan quaternary ammonium salt aqueous solution, stirring at the speed of 1500r/min, adjusting the pH value to 5-6 after dripping, continuously stirring at the speed of 1500r/min, and stirring for 30min to obtain mugwort oil/sodium alginate emulsion/chitosan quaternary ammonium salt emulsion;

(4) Slowly dropwise adding a calcium chloride solution into the mugwort oil/sodium alginate emulsion/chitosan quaternary ammonium salt emulsion, wherein the addition amount of the calcium chloride solution is 30% of the volume of the sodium alginate aqueous solution, and reacting for 3 hours in a water bath at 45 ℃ to obtain an antibacterial microcapsule suspension;

(5) The above-mentioned antibacterial microcapsule suspension was centrifugally washed 3-5 times and freeze-dried for 12 hours to obtain the antibacterial microcapsule of example 3.

The preparation of the antibacterial inner layer base fabric of example 3 includes the following:

the antibacterial finishing liquid comprises the following components: 2D resin 125 g/L, solidAntibacterial microcapsules 55g/L, mgCl of example 3 ₂ 15 An antibacterial finishing liquid was prepared by the formulation of g/L, JFC penetrant 1.0 g/L, and the base fabric of example 1 was immersed in the antibacterial finishing liquid with a bath ratio of 1:30, soaking at 40deg.C for 1.5. 1.5 h, baking at 60deg.C for 3 min, and naturally air-drying to obtain the antibacterial inner layer base fabric of example 3.

Example 4

The preparation of the antimicrobial microcapsules of example 4 comprises the steps of:

(1) Respectively preparing 1.5% sodium alginate aqueous solution, 0.75% chitosan quaternary ammonium salt aqueous solution and 6% calcium chloride solution;

(2) Adding tween-80 emulsifier into the sodium alginate aqueous solution, wherein the addition amount of the tween-80 emulsifier is 1.5 percent of the volume of the sodium alginate aqueous solution, and uniformly stirring, and then according to the core-wall ratio of 1:1 adding carvacrol serving as an antibacterial agent to obtain antibacterial liquid, and shearing the antibacterial liquid at a speed of 12000r/min for 15min to obtain carvacrol/sodium alginate emulsion with an oil-in-water structure;

(3) Taking chitosan quaternary ammonium salt aqueous solution with the volume 3 times of that of the sodium alginate aqueous solution, slowly dripping carvacrol/sodium alginate emulsion into the chitosan quaternary ammonium salt aqueous solution, stirring at the speed of 1200r/min, adjusting the pH value to 5-6 after dripping, continuously stirring at the speed of 1200r/min for 30min, and obtaining carvacrol/sodium alginate emulsion/chitosan quaternary ammonium salt emulsion;

(4) Slowly dropwise adding a calcium chloride solution into the carvacrol/sodium alginate emulsion/chitosan quaternary ammonium salt emulsion, wherein the addition amount of the calcium chloride solution is 40% of the volume of the sodium alginate aqueous solution, and reacting for 2.5h in a water bath at 50 ℃ to obtain an antibacterial microcapsule suspension;

(5) The above-mentioned antibacterial microcapsule suspension was centrifugally washed 3-5 times and freeze-dried for 12 hours to obtain the antibacterial microcapsule of example 4.

The preparation of the antibacterial inner layer base fabric of example 4 includes the following:

the antibacterial finishing liquid comprises the following components: 2D resin 125 g/L, antimicrobial microcapsules 55g/L, mgC of example 4l ₂ 15 An antibacterial finishing liquid was prepared by the formulation of g/L, JFC penetrant 1.0 g/L, and the base fabric of example 1 was immersed in the antibacterial finishing liquid with a bath ratio of 1:30, soaking at 40deg.C for 1.5. 1.5 h, baking at 60deg.C for 3 min, and naturally air-drying to obtain the antibacterial inner layer base fabric of example 4.

The antibacterial microcapsules prepared in examples 2 to 4 above were tested for encapsulation efficiency, drug loading rate, yield, and sustained release performance (25 ℃) according to the following test methods, and the test results are shown in Table 3 and FIG. 6.

The detection method comprises the following steps: accurately weighing 0.2g of dried antibacterial microcapsules, placing in 100 mL absolute ethyl alcohol, uniformly stirring, ultrasonically oscillating for 40min at 50 ℃ in an ultrasonic cleaner, then placing in a constant-temperature water bath shaking table at 37 ℃ for 24 h at 150 r/min, ultrasonically oscillating for 40min at 50 ℃ every 8h in the ultrasonic cleaner, fully releasing antibacterial agents in the antibacterial microcapsules, vacuum-filtering the mixed solution, centrifuging the obtained filtrate on a high-speed centrifuge for 20min, taking out supernatant, and measuring the absorbance of the obtained liquid at the maximum absorption wavelength by an ultraviolet-visible light spectrophotometer. The absorbance value is brought into an antimicrobial-ethanol standard curve to obtain the concentration of the antimicrobial in the liquid. And calculating the content of the antibacterial agent in the antibacterial microcapsule by combining the liquid volume. Then, the encapsulation efficiency, drug loading rate, and yield were calculated by the following formulas.

Encapsulation efficiency = mass of antimicrobial agent within antimicrobial microcapsule/mass of antimicrobial agent input x 100%;

drug loading = mass of antimicrobial agent within antimicrobial microcapsule/mass of antimicrobial microcapsule x 100%;

yield = mass of antimicrobial microcapsules/total mass of raw materials charged x 100%.

TABLE 3 test results of antibacterial microcapsules of examples 2-4

As can be seen from tables 3 and 6, the antibacterial microcapsules of examples 2-4 prepared by the preparation process of the present invention have high encapsulation efficiency, drug loading rate and yield, and have good slow release performance.

The antibacterial inner layer base cloths prepared in examples 2 to 4 above were tested for antibacterial property, air permeability, and moisture permeability according to the following test methods, and the test results are shown in table 4.

(1) Antibacterial properties: the antibacterial performance of the antibacterial inner layer base cloth prepared in examples 2 to 4 was detected by an shake flask method, and the detected strain was gram-negative bacterium escherichia coli, gram-positive bacterium staphylococcus aureus.

(2) Air permeability: refer to GB/T24218-2009.

(3) Moisture permeability: refer to GB/T12704.1-2009.

TABLE 4 test results of antibacterial inner base fabrics of examples 2-4

As can be seen from Table 4, the antibacterial inner layer base fabrics of examples 2 to 4 prepared by the preparation process of the present invention all have excellent antibacterial properties and air and moisture permeability, wherein the antibacterial inner layer base fabric of example 4 is considered to be optimal.

Comparative example 1 and example 5 below provide a waterproof and antibacterial outer base fabric and a preparation process thereof.

The raw materials DMF, poly (butylene adipate/terephthalate), azodicarbonamide and ZnO used in comparative example 1 and example 5 are all commercially available.

Comparative example 1

The waterproof antibacterial outer layer base cloth of comparative example 1 was prepared, comprising the following contents: the poly (adipic acid)/butylene terephthalate was dissolved in DMF to prepare a poly (adipic acid)/butylene terephthalate solution with a solid content of 20%, the poly (adipic acid)/butylene terephthalate solution was scraped on the antibacterial inner-layer base fabric of example 4 by a film coater to form a waterproof film layer 21 of 60 μm, left naturally for 2 hours, then soaked in a pure water gel bath, taken out after soaking at room temperature for 6 hours, taken out after replacing a new pure water gel bath, and left in room temperature dust-free air to be naturally dried to obtain the waterproof antibacterial outer-layer base fabric of comparative example 1.

Example 5

The waterproof and antibacterial outer layer base fabric of example 5 was prepared, comprising the following: the method comprises the steps of dissolving poly (butylene adipate/terephthalate) in DMF to obtain a poly (butylene adipate/terephthalate) solution with a solid content of 20%, and mixing the poly (butylene adipate/terephthalate) solution, azodicarbonamide and ZnO according to a mass ratio of 100:1:1, scraping the mixture on the antibacterial inner layer base cloth of the embodiment 4 through a film coater to form a waterproof film layer 21 with 60 mu m, naturally standing for 2 hours, soaking the waterproof film layer in a pure water gel bath, soaking the waterproof film layer in the pure water gel bath at room temperature for 6 hours, taking out the waterproof film layer, replacing the pure water gel bath, continuously soaking the waterproof film layer in the pure water gel bath for 6 hours, taking out the waterproof film layer, and naturally airing the waterproof film layer in the dust-free air at room temperature to obtain the waterproof antibacterial outer layer base cloth of the embodiment 5.

The waterproof antibacterial outer layer base fabrics prepared in comparative example 1 and example 5 were tested for waterproof property, air permeability, moisture permeability, and pore diameter according to the following test methods, and the test results are shown in table 5.

(1) Waterproof property: the waterproof film layers of comparative example 1 and example 5 were tested for contact angle by a contact angle meter to determine the waterproof property.

(2) Air permeability: refer to GB/T24218-2009.

(3) Moisture permeability: refer to GB/T12704.1-2009.

(4) Pore diameter: the pore diameters of the waterproof membrane layers of comparative example 1 and example 5 were measured by a metallographic microscope.

TABLE 5 test results for comparative example 1, example 5

As can be seen from table 5, both the pore diameters of comparative example 1 and example 5 are between the diameters of the water vapor molecule and the liquid water droplet molecule, and have better water repellency, but the example 5 can form a more uniform open pore structure under the pore-forming nucleation of azodicarbonamide and the activation of ZnO, so that example 5 has better air permeability and moisture permeability than comparative example 1.

Comparative examples 2-4 and examples 6-7 below provide a composite fiber fabric and a process for preparing the same.

The PLA, PCL, and hexagonal boron nitride (radial dimension 10 μm) used as raw materials in comparative examples 2 to 4 and examples 6 to 7 are all commercially available.

Comparative example 2

The composite fiber fabric of comparative example 2 was prepared, comprising the following: the waterproof antibacterial outer layer base cloth of example 5 and the antibacterial inner layer base cloth of example 4 were compounded into a whole by a hot roll hot press to obtain a composite fiber fabric of comparative example 2, and the waterproof film layer of the waterproof antibacterial outer layer base cloth was disposed with one side facing outward. Wherein, the parameters of the hot roller hot press are set as follows: the heat rolling lamination speed is 2.5r/min, and the heat treatment temperature is 90 ℃.

Comparative example 3

The preparation of the composite fiber fabric of the comparative example 3 comprises the following steps:

(1) PLA, PCL according to 90:10, dissolving in a solvent (mixed solvent of chloroform and DMF, the mass ratio is 7:3), continuously stirring for 5 hours at 70 ℃ to prepare a heat-conducting spinning solution with the concentration of 12wt%, coating the antibacterial inner layer base cloth of the embodiment 4 on a roller for a week, carrying out ultrasonic treatment on the heat-conducting spinning solution for 20 minutes, and spinning on the antibacterial inner layer base cloth of the roller by an electrostatic spinning machine to obtain a composite fiber membrane; wherein, parameters of the electrostatic spinning machine are set as follows: positive voltage 25KV, negative voltage 2KV, push injection speed of heat conduction spinning solution 0.08mm/min, fixed distance from needle to cylinder 15cm, translation speed of electrostatic spinning machine 400mm/min, and received cylinder rotation speed 150rpm/min;

(2) The waterproof and antibacterial outer-layer base cloth of example 5 and the antibacterial inner-layer base cloth covered with the composite fiber membrane are compounded into a whole by a hot roll hot press to obtain the composite fiber fabric of comparative example 3, and the waterproof membrane layer of the waterproof and antibacterial outer-layer base cloth is arranged with one side facing outwards. Wherein, the parameters of the hot roller hot press are set as follows: the heat rolling lamination speed is 2.5r/min, and the heat treatment temperature is 90 ℃.

Comparative example 4

The composite fiber fabric of comparative example 4, as shown in fig. 1, comprises an antibacterial inner layer base cloth 1, a waterproof antibacterial outer layer base cloth 2 and a heat-conducting composite fiber membrane 3, wherein the antibacterial inner layer base cloth 1, the heat-conducting composite fiber membrane 3 and the waterproof antibacterial outer layer base cloth 2 are sequentially laminated and compounded into a whole by hot pressing.

The preparation of the composite fiber fabric of comparative example 4 comprises the following steps:

(1) PLA, PCL and hexagonal boron nitride are mixed according to 89:9:2, dissolving in a solvent (mixed solvent of chloroform and DMF, the mass ratio is 7:3), continuously stirring for 5 hours at 70 ℃ to prepare a heat-conducting spinning solution with the concentration of 12wt%, coating the antibacterial inner layer base cloth 1 of the embodiment 4 on a roller for a week, carrying out ultrasonic treatment on the heat-conducting spinning solution for 20 minutes, and spinning on the antibacterial inner layer base cloth 1 of the roller by an electrostatic spinning machine to obtain a heat-conducting composite fiber membrane 3; wherein, parameters of the electrostatic spinning machine are set as follows: positive voltage 25KV, negative voltage 2KV, push injection speed of heat conduction spinning solution 0.08mm/min, fixed distance from needle to cylinder 15cm, translation speed of electrostatic spinning machine 400mm/min, and received cylinder rotation speed 150rpm/min;

(2) The waterproof and antibacterial outer-layer base cloth 2 of example 5 and the antibacterial inner-layer base cloth 1 covered with the heat conductive composite fiber film 3 were compounded into a whole by a hot roll hot press to obtain a composite fiber fabric of comparative example 4, and the waterproof film layer 21 of the waterproof and antibacterial outer-layer base cloth 2 was disposed with one side facing outward. Wherein, the parameters of the hot roller hot press are set as follows: the heat rolling lamination speed is 2.5r/min, and the heat treatment temperature is 90 ℃.

Example 6

The composite fiber fabric of example 6, as shown in fig. 1, comprises an antibacterial inner layer base cloth 1, a waterproof antibacterial outer layer base cloth 2, and a heat-conducting composite fiber membrane 3 (one surface is provided with a waterproof membrane layer 21), and the antibacterial inner layer base cloth 1, the heat-conducting composite fiber membrane 3, and the waterproof antibacterial outer layer base cloth 2 are sequentially laminated and heat-pressed and compounded into a whole.

The preparation of the composite fiber fabric of example 6 comprises the following steps:

(3) PLA, PCL and dopamine modified boron nitride are prepared according to 89:9:2, dissolving in a solvent (mixed solvent of chloroform and DMF, the mass ratio is 7:3), continuously stirring for 5 hours at 70 ℃ to prepare a heat-conducting spinning solution with the concentration of 12wt%, coating the antibacterial inner layer base cloth 1 of the embodiment 4 on a roller for a week, carrying out ultrasonic treatment on the heat-conducting spinning solution for 20 minutes, and spinning on the antibacterial inner layer base cloth 1 of the roller by an electrostatic spinning machine to obtain a heat-conducting composite fiber membrane 3; wherein, parameters of the electrostatic spinning machine are set as follows: positive voltage 25KV, negative voltage 2KV, push injection speed of heat conduction spinning solution 0.08mm/min, fixed distance from needle to cylinder 15cm, translation speed of electrostatic spinning machine 400mm/min, and received cylinder rotation speed 150rpm/min;

(4) The waterproof and antibacterial outer-layer base cloth 2 of example 5 and the antibacterial inner-layer base cloth 1 covered with the heat-conductive composite fiber film 3 are compounded into a whole by a hot roll hot press to obtain the composite fiber fabric of example 6, and the waterproof film layer 21 of the waterproof and antibacterial outer-layer base cloth 2 is arranged outwards. Wherein, the parameters of the hot roller hot press are set as follows: the heat rolling lamination speed is 2.5r/min, and the heat treatment temperature is 90 ℃.

Example 7

The composite fiber fabric of example 7, as shown in fig. 2, comprises an antibacterial inner layer base cloth 1, a PCL adhesive film a, a waterproof antibacterial outer layer base cloth 2 (one surface is provided with a waterproof film layer 21), a PCL adhesive film a, a heat conductive composite fiber film 3, and the antibacterial inner layer base cloth 1, the PCL adhesive film a, the heat conductive composite fiber film 3, the PCL adhesive film a, the waterproof antibacterial outer layer base cloth 2, the waterproof film layer 21 are sequentially arranged and thermally pressed and compounded into one body.

The preparation of the composite fiber fabric of example 7 comprises the following steps:

(1) PLA, PCL and dopamine modified boron nitride are prepared according to 89:9:2, dissolving in a solvent (mixed solvent of chloroform and DMF, the mass ratio is 7:3), continuously stirring for 5 hours at 70 ℃ to prepare a heat-conducting spinning solution with the concentration of 12wt%, spraying a layer of PCL adhesive film a (the thickness is 20 mu m) on one side of the antibacterial inner layer base cloth of the embodiment 6, coating the antibacterial inner layer base cloth 1 on a roller for one week and arranging the PCL adhesive film a outwards, carrying out ultrasonic treatment on the heat-conducting spinning solution for 20 minutes, and spinning on the antibacterial inner layer base cloth 1 coated with the PCL adhesive film a through an electrostatic spinning machine to obtain the heat-conducting composite fiber film 3; wherein, parameters of the electrostatic spinning machine are set as follows: positive voltage 25KV, negative voltage 2KV, push injection speed of heat conduction spinning solution 0.08mm/min, fixed distance from needle to cylinder 15cm, translation speed of electrostatic spinning machine 400mm/min, and received cylinder rotation speed 150rpm/min;

(2) A PCL adhesive film a (thickness of 20 μm) was sprayed on the opposite side of the waterproof film layer 21 of the waterproof and antibacterial outer-layer base cloth 2, and the PCL adhesive film a and the antibacterial inner-layer base cloth 1 covered with the heat-conductive composite fiber film 3 were compounded into a whole by a hot roll hot press to obtain the composite fiber fabric of example 7, and the waterproof film layer 21 of the waterproof and antibacterial outer-layer base cloth 2 was provided with the facing side facing outward. Wherein, the parameters of the hot roller hot press are set as follows: the heat rolling lamination speed is 2.5r/min, and the heat treatment temperature is 90 ℃.

Wherein, the dopamine-modified boron nitride adopted in examples 6-7 is prepared by modifying hexagonal boron nitride with dopamine, and the chemical formula of the dopamine-modified boron nitride is as follows:

。

the composite fiber fabrics prepared in comparative examples 2 to 4 and examples 6 to 7 were tested for protective filterability, air permeability, moisture permeability, antibacterial property, and thermal conductivity according to the following test methods, and the test results are shown in table 6.

(1) Protective filtering performance: and testing the protective filtering performance by adopting a TSI8130A automatic filter material tester. The composite fiber fabric was cut into a round shape with a diameter of 30 cm, and the filtration efficiency was tested at an air flow rate of 15L/min.

(2) Air permeability: refer to GB/T24218-2009.

(3) Moisture permeability: refer to GB/T12704.1-2009.

(4) Antibacterial properties: the shake flask method was employed.

(5) Thermal conductivity: the thermal conductivity was tested with reference to ISO22007 standard.

Table 6 test results for comparative examples 2 to 4 and examples 6 to 7

As can be seen from Table 6, the filtration efficiency of the composite fiber fabrics prepared in comparative examples 2-4 and examples 6-7 is greater than or equal to 90%, and the filtration efficiency of the medical protective clothing is more than or equal to 70% according to the technical requirement of the medical disposable protective clothing of national standard GB19082-2009, which meets the requirements.

Compared with comparative example 2, comparative examples 3-4 and examples 6-7 have a certain influence on the air permeability and the moisture permeability of the composite fiber fabric due to the fact that the composite fiber film or the heat conducting composite fiber film is arranged between the antibacterial inner layer base cloth and the waterproof antibacterial outer layer base cloth.

However, compared with comparative example 3, comparative examples 4 and examples 6 to 7, the porosity of the heat conductive composite fiber film is increased due to the doped hexagonal boron nitride or dopamine modified boron nitride in the heat conductive composite fiber film, and the increased gaps and channels are more beneficial to the passage of air flow, so that the air permeability and the moisture permeability are improved.

In addition, in the comparative example 4 and the examples 6-7, hexagonal boron nitride or dopamine modified boron nitride is doped in the heat-conducting composite fiber membrane, so that the heat conducting property of the composite fiber fabric is improved, the evaporation of sweat of a human body can be promoted, the composite fiber fabric is enabled to generate a cooling effect in a heat conduction mode, the heat and humidity comfort of a user is improved, and the heat conducting property of the example 6-7 doped with dopamine modified boron nitride is better than that of the comparative example 4 doped with hexagonal boron nitride.

The composite fiber fabric of example 6 is considered optimally, and the composite fiber fabric of example 7 has a certain influence on air permeability, moisture permeability, thermal conductivity and the like due to the addition of the PCL adhesive film, but the addition of the PCL adhesive film can reduce the problems of easy separation between layers and poor mechanical property of the composite fabric.

In addition, the invention also relates to a device used in the preparation process of the waterproof antibacterial composite fiber fabric for the medical product, namely a hydroentangler, and the invention is further elucidated below with reference to figures 3-5 and specific examples 8-10.

Example 8

As shown in fig. 3 and 4, the hydroentangling machine according to the present invention comprises a net curtain 41, a guide roller 42, a hydroentangling head 43, a negative pressure suction dehydrator 44, a gas-water separator 51, a backwater collecting tank 52, a sand filter group 53, a clean water tank 54, a metal filter 55 and a high pressure pump 56.

After the water body is pressurized by the high-pressure pump 56, the water body is continuously sprayed from the water jet head 43 onto the pre-wetted fiber web b supported by the net curtain 41 and the guide rollers 42, a plurality of fine water jets sprayed by the water needle plate needles of the water jet head 43 vertically irradiate the fiber web b, so that a part of surface fibers in the fiber web b are displaced, and after the water jets penetrate the fiber web b, the water jets are reflected by the surface of the net curtain 41 and are scattered to the reverse surface of the fiber web b in different directions. Under the dual actions of direct impact of water jet and rebound of water jet, the fibers in the fiber net b displace, interpenetrate, intertwine and cohesion to form countless flexible intertwining points, so that the fiber net is reinforced to form a stable intertwining structure. In the water jet process, the retained water in the fiber web b is sucked through a plurality of negative pressure suction dehydrators 44, the water sucked by the negative pressure suction dehydrators 44 is separated by the gas-water separator 51 of the water jet backwater treatment mechanism 5, and is collected by the backwater collecting tank 52, filtered by the sand filter group 53, the clean water tank 54 is reserved, fine filtered by the metal filter 55 and pressurized by the high pressure pump 56, so that impurities such as fiber oil, various fiber short scraps and microfibrils separated from fibers, cellulose aggregates and the like in the water are removed, and the water is returned to the water jet 43, thereby avoiding the occurrence of the phenomena of water needle plate blockage and water needle plate needle hole abrasion deformation of the water jet 43, reducing stripes of the fiber web b caused by needle plate blockage, ensuring the water jet effect and saving water resources.

Example 9

The structural basis based on embodiment 8 above is shown in fig. 3, 4 and 5.

According to the water thorn machine, the sand filter 531 is of a double-chamber structure, namely 2 sand filter chambers 5311, a filter material layer 5312, a cushion material layer 5313 and a drainage system 5314 are arranged in each sand filter chamber 5311 from top to bottom, and when in back flushing, one sand filter chamber 5311 can be back flushed, and the other sand filter chamber 5311 can be continuously used for filtering, so that the sand filter 531 can continuously work.

Example 10

The structural basis based on embodiment 8 or embodiment 9 above is shown in fig. 3, 4, and 5.

The water thorn machine of the invention, the sand filter group 53 includes sand filter 531, back flush sedimentation tank 532, the design of sand filter 531, back flush sedimentation tank 532 makes two processes of filtration-back flush go on alternately, along with the impurity deposit of sand filter 531 is too much, the resistance is too big, when the water level rises to certain height, the water is blocked, carry on back flush to sand filter 531 at this moment, back flush rivers to back flush sedimentation tank 532, a large amount of suspended solids in the back flush water are precipitated and released under the flocculating agent effect of back flush sedimentation tank 532 first, then drain back water collecting tank 52, can lengthen the filtration cycle of sand filter 531.

Specifically: after the water body subjected to the water thorn is subjected to gas-water separation by the gas-water separator 51, the water body is distributed into the sand filter chamber 5311 from the water inlet pipe 533 through the water inlet channel 534 and the water drainage groove 535, the water body penetrates through the filter material layer 5312 and the cushion material layer 5313 from top to bottom in the sand filter chamber 5311, is collected by the water drainage system 5314 and is discharged into the clean water tank 54 through the water drainage pipe 536, and during operation, the sand filter chamber 5311 is in a fully immersed state. As the impurities on the filter layer 5312 gradually settle, the resistance becomes greater and greater, so that the water level rises, and when the water level rises to a certain height, the water is blocked, and the sand filter 5311 is backwashed. During back flushing, the water inlet valve of the water inlet pipe 533 and the water outlet valve of the water outlet pipe 536 are closed, the back flushing water inlet valve of the back flushing water inlet pipe 537 and the back flushing water outlet pipe 538 are opened, and back flushing water passes through the water outlet system 5314, the padding layer 5313 and the filter material layer 5312 from bottom to top, is collected by the water outlet tank 535 and is discharged to the back flushing sedimentation tank 532 through the water inlet channel 534 and the back flushing water outlet pipe 538.

The specific preparation process of the invention has a plurality of ways, and the above is only a preferred embodiment of the invention. It should be noted that the above examples are only for illustrating the present invention and are not intended to limit the scope of the present invention. It will be apparent to those skilled in the art that modifications may be made without departing from the principles of the invention, and such modifications are intended to be within the scope of the invention.

Claims

1. The preparation process of the waterproof antibacterial composite fiber fabric for the medical product is characterized by comprising the following steps of:

s2: immersing the base cloth into the antibacterial finishing liquid for 0.5-2h, baking for 1-5min, naturally airing, wherein one part of the base cloth is used as an antibacterial inner base cloth (1) and the other part of the base cloth is used as a waterproof antibacterial outer base cloth semi-finished product; the antibacterial finishing liquid comprises the following components: 2D resin 120-130 g/L, antibacterial microcapsule 50-60 g/L, mgCl ₂ 10-20g/L, JFC penetrating agent 0.5-1.5g/L;

s3: scraping the waterproof finishing liquid on a semi-finished waterproof and antibacterial outer-layer base cloth product through a film coater to form a waterproof film layer (21) with the thickness of 50-500 mu m, naturally placing for 1-2h, then soaking in a pure water gel bath, soaking in a water gel bath at room temperature for 12-24-h, and naturally airing to obtain a waterproof and antibacterial outer-layer base cloth (2); the waterproof finishing liquid comprises the following raw materials in parts by weight: 90-100 parts of poly (adipic acid)/butylene terephthalate solution, 0.5-2 parts of azodicarbonamide and 0.1-0.5 part of ZnO; the poly (adipic acid)/butylene terephthalate solution is prepared by dissolving poly (adipic acid)/butylene terephthalate in DMF (dimethyl formamide) and has a solid content of 10-30%;

S4: PLA, PCL and heat conducting particles are mixed according to 80-90:8-12:2-4, dissolving in a solvent, continuously stirring for 5-6 hours at 70-80 ℃ to prepare a heat-conducting spinning solution with the concentration of 5-15wt%, coating the antibacterial inner layer base cloth (1) on a roller for a week, carrying out ultrasonic treatment on the heat-conducting spinning solution for 10-30 minutes, and spinning on the antibacterial inner layer base cloth (1) of the roller by an electrostatic spinning machine to obtain a heat-conducting composite fiber membrane (3);

s5: the waterproof antibacterial outer-layer base cloth (2) and the antibacterial inner-layer base cloth (1) covered with the heat-conducting composite fiber film (3) are compounded into a whole through a hot roller hot press, and one surface of the waterproof film layer (21) of the waterproof antibacterial outer-layer base cloth (2) faces outwards.

2. The process for preparing a waterproof and antibacterial composite fiber fabric for medical products according to claim 1, wherein the waterproof and antibacterial composite fiber fabric comprises:

an antibacterial inner layer base cloth (1);

a waterproof antibacterial outer layer base cloth (2);

the heat-conducting composite fiber membrane (3), the antibacterial inner layer base cloth (1), the heat-conducting composite fiber membrane (3) and the waterproof antibacterial outer layer base cloth (2) are sequentially laminated and are combined into a whole through hot pressing.

3. The process for preparing the waterproof and antibacterial composite fiber fabric for medical products according to claim 1, wherein in the step S2, the base fabric is immersed in the antibacterial finishing liquid, and the bath ratio is 1:20-40, soaking at 30-50deg.C, baking at 50-70deg.C for 1-5min; the antibacterial microcapsules in the antibacterial finishing liquid are of spherical structures, and the average particle size is 1-5 mu m; the antibacterial microcapsule comprises a wall material and a core material, wherein the wall material is sodium alginate and chitosan quaternary ammonium salt, the core material is an antibacterial agent, and the wall material wraps the core material.

4. The process for preparing the waterproof and antibacterial composite fiber fabric for medical products according to claim 1, wherein the preparation of the antibacterial microcapsules comprises the following steps:

(3) Taking chitosan quaternary ammonium salt aqueous solution with the volume of 2-4 times of that of the sodium alginate aqueous solution, slowly dripping the antibacterial agent/sodium alginate emulsion into the chitosan quaternary ammonium salt aqueous solution, stirring at the speed of 1200-1500r/min, adjusting the pH value to 5-6 after dripping, continuously stirring at the speed of 1200-1500r/min, and stirring for 20-30min to obtain the antibacterial agent/sodium alginate emulsion/chitosan quaternary ammonium salt emulsion;

5. The process for preparing the waterproof and antibacterial composite fiber fabric for medical products according to claim 3 or 4, wherein the antibacterial agent is one or a combination of more of thymol, oregano oil, mugwort oil, carvacrol, weeping forsythiae oil, citronella oil and mugwort essential oil; the heat conducting particles are dopamine modified boron nitride.

6. The process for preparing the waterproof and antibacterial composite fiber fabric for the medical product according to claim 1, wherein in the step S4, a layer of PCL adhesive film is sprayed on one side of the antibacterial inner layer base fabric (1), the antibacterial inner layer base fabric (1) is covered on a circle of a roller, one side of the PCL adhesive film is outwards arranged, then the heat-conducting spinning solution is subjected to ultrasonic treatment for 10-30min, and then the heat-conducting composite fiber film (3) is obtained by spinning on the antibacterial inner layer base fabric (1) covered with the PCL adhesive film through an electrostatic spinning machine; in the step S5, a PCL adhesive film is sprayed on one surface of the waterproof antibacterial outer layer base cloth (2) in the direction opposite to the waterproof film layer (21), the waterproof antibacterial outer layer base cloth (2) and the antibacterial inner layer base cloth (1) covered with the heat-conducting composite fiber film (3) are compounded into a whole through a hot roller hot press, and one surface of the waterproof film layer (21) of the waterproof antibacterial outer layer base cloth (2) faces outwards.

7. The process for preparing the waterproof and antibacterial composite fiber fabric for medical products according to claim 1, wherein in S4, parameters of an electrostatic spinning machine are set as follows: positive voltage 20-30 KV, negative voltage 1-5KV, push injection speed of heat conduction spinning solution 0.05-0.2mm/min, needle-to-drum distance fixed at 10-30cm, translation speed of electrostatic spinning machine at 300-600mm/min, and received drum rotation speed at 100-200rpm/min; in the step S5, parameters of the hot roll hot press are set as follows: the heat rolling attaching speed is 1-5 r/min, and the heat treatment temperature is 80-100 ℃.

8. The process for preparing a waterproof and antibacterial composite fiber fabric for medical products according to claim 1, wherein the hydroentangling machine for S1 comprises:

the hydroentangling mechanism (4) comprises a net curtain (41), a plurality of guide rollers (42), a plurality of hydroentangling heads (43) and a plurality of negative pressure suction dehydrators (44); the net curtain (41) is of an annular structure, sleeved on the guide rollers (42), and forms annular conveying of the net curtain (41) through rotation of the guide rollers (42) so as to support the fiber net; a plurality of water thorn heads (43) are uniformly distributed above the net curtain (41), a plurality of negative pressure suction dehydrators (44) are uniformly distributed below the net curtain (41), and the water thorn heads (43) and the negative pressure suction dehydrators (44) are correspondingly arranged up and down;

The water thorn return water treatment mechanism (5) comprises a gas-water separator (51), a return water collecting tank (52), a sand filter tank group (53), a clean water tank (54), a metal filter (55) and a high-pressure pump (56), wherein an outlet of the negative pressure suction dehydrator (44), the gas-water separator (51), the return water collecting tank (52), the sand filter tank group (53), the clean water tank (54), the metal filter (55), the high-pressure pump (56) and an inlet of the water thorn head (43) are sequentially connected through pipelines.

9. The process for preparing the waterproof and antibacterial composite fiber fabric for medical products according to claim 8, wherein the water needling machine for S1, the sand filter group (53) comprises:

the sand filter (531), the sand filter (531) is of a double-chamber structure, comprises 2 sand filter chambers (5311), and each sand filter chamber (5311) is internally provided with a filter material layer (5312), a padding layer (5313) and a drainage system (5314) from top to bottom; the backwater collecting tank (52), the sand filtering chamber (5311) and the clean water tank (54) are sequentially connected through pipelines;

and the sand filter (531), the backwash sedimentation tank (532) and the backwater collecting tank (52) are sequentially connected through pipelines.

10. The process for preparing a waterproof and antibacterial composite fiber fabric for medical products according to claim 9, wherein the sand filter group (53) further comprises:

a water inlet pipe (533), wherein the water inlet pipe (533) is provided with a water inlet valve;

a water inlet channel (534);

the water inlet of the backwater collecting tank (52), the water inlet pipe (533), the water inlet channel (534), the water outlet tank (535) and the sand filtering chamber (5311) are sequentially connected;

the water outlet of the sand filtering chamber (5311), the water outlet pipe (536) and the clean water tank (54) are sequentially connected; the drain pipe (536) is provided with a drain valve;

a backwash inlet pipe (537);

a back flush outlet pipe (538), a back flush port of the sand filter chamber (5311), a back flush inlet pipe (537), a drainage tank (535), a water inlet channel (534), a back flush outlet pipe (538) and a water inlet of a back flush sedimentation tank (532) are sequentially connected; the back flush water inlet pipe (537) is provided with a back flush water inlet valve, and the back flush water outlet pipe (538) is provided with a back flush water washing valve.