CN115946430A

CN115946430A - Preparation process of waterproof antibacterial composite fiber fabric for medical products

Info

Publication number: CN115946430A
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: 2023-04-11
Anticipated expiration: 2043-03-10
Also published as: CN115946430B

Abstract

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

Description

Preparation process of waterproof antibacterial composite fiber fabric for medical products

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 rapid increase of the demand of medical protection products, the production and the use of the fabrics for medical products are greatly increased. At present, the following problems to be solved are present in the fabrics for medical products: 1. in order to achieve better barrier property, most of fabrics for medical products contain non-degradable polymer materials, so that the environment pollution is large; 2. waterproof property and moisture permeability cannot be considered, and long-time wearing can affect the delivery of hot water vapor of a wearer in a sweating period, so that heat load is caused; 3. when the medical product fabric is worn, if germs are easily carried on the surface of the medical product fabric, the medical product fabric needs to be replaced frequently, and waste is caused; 4. after the medical product fabric is worn for a long time, the loss and the generation of human body heat cannot reach balance, the heat in the body of a wearer cannot be normally dissipated, thermal fatigue is caused, and strong stuffy feeling can be generated under high-strength work, so that the body is uncomfortable.

The Chinese patent application No. CN202210928277.5 discloses an antibacterial ultraviolet-proof high-efficiency low-resistance micro-nano fiber mask fabric and a preparation method thereof, wherein the antibacterial ultraviolet-proof high-efficiency low-resistance micro-nano fiber 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. According to the patent, a PP spun-bonded non-woven fabric-nanofiber membrane prepared through electrostatic spinning is respectively used as an outer layer and an intermediate layer, then viscose spunlace non-woven fabric is covered to be used as an inner layer, the antibacterial performance is improved by using a nanoscale Ag, GO or non-metal ion doped photocatalytic antibacterial agent, and the waterproof performance is improved by using a hydrophobic PP spun-bonded non-woven fabric as an outer layer. The patent does not solve the problems that the fabric for the medical product contains non-degradable components to cause environmental pollution, and the water resistance and the moisture permeability can not be considered at the same time, and the heat can not be normally dissipated after the fabric is 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 the preparation process has the characteristics of water resistance, antibiosis, heat conduction, good heat and humidity comfort and biodegradability.

In addition, many fabrics for medical products comprise non-woven fabrics, particularly spunlace non-woven fabrics, the speed is high by adopting a spunlace process, the time from fibers to the non-woven fabrics is only 5 minutes, links such as spinning, spooling, warping and weaving and the like in the 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 for processing the non-woven fabric by the spunlace machine is large and is different from 50 t/h to 500t/h, and the water for processing the non-woven fabric by the spunlace machine can generate fiber oiling agents, various fiber short scraps, microfibril separated from the fibers, cellulose aggregates and other impurities. Therefore, if the water cannot be used, the waste is very large. However, if the water is not properly treated, the quality of the product is directly affected, and even the hydro-entangling machine cannot normally operate. For example, the above-mentioned impurities and dirt block the pinholes of the water needle plate to affect the product quality, and may also cause deformation of the needle plate.

Therefore, another object of the present invention is to develop a device for treating and utilizing the backwater of the spunlace machine in the preparation process of the composite fiber fabric for medical products, so as to improve the recovery and utilization rate of the backwater of spunlace, reduce the cost and avoid the waste of water resources.

Disclosure of Invention

The purpose of the invention is as follows: in order to overcome the defects, the invention aims to provide a preparation process of a waterproof and antibacterial composite fiber fabric for medical products, the process steps are reasonably designed, the prepared composite fiber fabric has a three-layer structure of antibacterial inner-layer base cloth, a heat-conducting composite fiber film and waterproof and antibacterial outer-layer base cloth, the waterproof, antibacterial and heat-conducting properties are improved under the condition of ensuring high protection, moisture permeability and air permeability, and the waterproof and antibacterial composite fiber fabric has the advantages of high protection safety, good heat and humidity comfort and biodegradability, is suitable for medical products and has wide application prospect.

The purpose of the invention is realized by the following technical scheme:

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

s1: mixing China hemp fibers, viscose fibers and PLA fibers according to the weight ratio of 4-6:2-3:1-3, opening by an opener, carding by a carding machine to obtain a fiber web, reinforcing the fiber web by a spunlace machine to obtain base cloth, and naturally airing the base cloth for later use;

s2: soaking the base cloth in the antibacterial finishing liquid for 0.5-2h, baking for 1-5min, and naturally drying, wherein one part of the base cloth is used as an antibacterial inner layer base cloth, and the other part of the base cloth is used as a waterproof antibacterial outer layer base cloth semi-finished product; the antibacterial finishing liquid comprises: 120-130g/L of 2D resin, 50-60g/L of antibacterial microcapsule and MgCl ₂ 10-20g/L and 0.5-1.5g/L of JFC penetrant;

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

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

s5: the waterproof and 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 rolling hot press, and one side of a waterproof membrane layer of the waterproof and antibacterial outer layer base cloth faces outwards.

The preparation process of the waterproof and antibacterial composite fiber fabric for the medical product is reasonable in design, the base cloth is prepared from degradable materials such as hemp fibers, viscose fibers and PLA fibers by a spunlace method, the hemp fibers are good in moisture absorption and air permeability and have certain natural functions (such as antibacterial and ultraviolet-resistant performances), but are poor in spinnability due to the fact that hairiness is large, hard and long, and impurities such as pectin and lignin in the hemp fibers are added, the problem that the hemp fibers are not easy to tangle and cohere can be solved by adding the long, thin and soft viscose fibers, the PLA fibers have good oxygen permeability, high barrier property and biocompatibility to smell and certain antibacterial and mildew-resistant performances, and the hot melt fiber PLA can be melted under a subsequent hot rolling hot pressing condition to solidify the hemp fibers, the viscose fibers and the heat conduction composite fiber film to form a more stable structure.

Then, the base fabric is subjected to microcapsule antibacterial finishing, and the crosslinking effect of 2D resin, the penetrating effect of JFC penetrating agent and MgCl are performed ₂ Under the catalytic action of the antibacterial finishing liquid, the antibacterial finishing liquid can permeate into the base cloth fibers and the antibacterial microcapsules in the dipping process, chemical bonds are formed between the antibacterial microcapsule walls and active groups on the base cloth fibers to form hydrogen bonds, so that the antibacterial microcapsules are stably and uniformly distributed and fixed on the base cloth, the antibacterial agent embedded in the antibacterial microcapsules can be slowly released due to the slow release performance of the antibacterial microcapsules, the antibacterial property of the base cloth is more durable, the antibacterial agent embedded in the antibacterial microcapsules 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, the outward surface of the waterproof antibacterial outer layer base cloth semi-finished product is subjected to waterproof finishing, a film forming method is adopted, polybutylene adipate/terephthalate is dissolved in a DMF solvent, azodicarbonamide and ZnO are added to prepare a waterproof finishing liquid, the polybutylene adipate/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 DMF solvent is soaked in a pure water gel bath for evaporation and drying, and under the pore-forming nucleation effect of the azodicarbonamide and the activation effect of the ZnO, a waterproof film layer with the pore diameter of 85-95 mu m is solidified, and the pore diameter of the waterproof antibacterial outer layer base cloth is between the diameters of water vapor molecules and liquid water drop molecules, and the dispersibility of pores is good, so that the waterproof antibacterial outer layer base cloth has excellent waterproof and air permeability.

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, through an electrostatic spinning technology, the heat-conducting particles are uniformly loaded on the heat-conducting composite fiber membrane, an interconnection heat-conducting frame is built in the heat-conducting composite fiber membrane, PLA and PCL are mixed to improve brittleness, the heat-conducting composite fiber membrane not only serves as a bonding layer between the antibacterial inner layer base cloth and the waterproof antibacterial outer layer base cloth (the PLA and the PCL can be fused under hot rolling and hot pressing conditions), but also serves as a heat-conducting layer to improve the heat transfer performance of the composite fiber fabric, the composite fiber fabric generates a cooling effect through a heat conduction mode, and therefore the heat-humidity comfort of a user is improved.

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

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

an antibacterial inner layer base fabric;

waterproof and antibacterial outer base cloth;

the heat-conducting composite fiber membrane comprises an antibacterial inner layer base cloth, a heat-conducting composite fiber membrane and a waterproof antibacterial outer layer base cloth which are sequentially stacked and hot-pressed to form a whole.

Preferably, the antibacterial inner-layer base cloth comprises a single-layer base cloth, or comprises a plurality of layers of base cloth, the plurality of layers of base cloth are stacked, arranged and compounded into a whole through hot pressing, and then the treatment is carried out through S2.

Preferably, the waterproof and antibacterial outer-layer base cloth also comprises a single-layer base cloth, or comprises a plurality of layers of base cloth, the plurality of layers of base cloth are stacked, arranged, hot-pressed and compounded into a whole, and then the treatment is carried out by S2 and S3.

The filtration efficiency of the base cloth to 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 filtration efficiency of 30-50% for the particles with the size of 2.5 μm under the wind speed of 40 cm/s. The filtering efficiency of the 3 layers of base cloth to particles with the size of 2.5 mu m can reach more than 99% under the wind speed of 40cm/s, and the mechanical property is not obviously changed. The number of layers of the base fabric is selected by those skilled in the art as needed.

Further, in the preparation process of the waterproof and antibacterial composite fiber fabric for medical products, in step S2, the base fabric is immersed in the antibacterial finishing liquid at a bath ratio of 1:20-40 deg.C, soaking at 30-50 deg.C, and baking at 50-70 deg.C for 1-5min; the antibacterial microcapsules in the antibacterial finishing liquid are of a spherical structure, and the average grain diameter 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.

Sodium alginate is an anionic polymer, chitosan quaternary ammonium salt is a cationic polymer, sodium alginate and chitosan quaternary ammonium salt with opposite charges flocculate through electrostatic interaction, phase separation occurs, gelation and solidification of a coacervate embed the core material antibacterial agent, 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 the medical product comprises the following steps:

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

(2) Taking the sodium alginate aqueous solution, adding a 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, uniformly stirring, and then mixing according to a core-wall ratio of 1-3:1-3, adding an antibacterial agent to obtain an antibacterial liquid, and shearing the antibacterial liquid at the speed of 10000-12000r/min for 5-15min to obtain an antibacterial agent/sodium alginate emulsion with an oil-in-water structure;

(3) Taking a chitosan quaternary ammonium salt aqueous solution with the volume 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 to 5-6 after finishing 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 (3) 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 characteristics 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 oil-in-water structure is added into chitosan quaternary ammonium salt aqueous solution with opposite charges to generate flocculation, and calcium chloride solution Ca is dropwise added ²⁺ And performing ion exchange with sodium alginate to perform cross-linking complexation, accelerating the gelation and solidification of the coacervate, performing centrifugal washing, and performing freeze drying to obtain the antibacterial microcapsule.

Preferably, the S3 is soaked in a pure water gel bath for 6-8 hours at room temperature and then taken out, a new pure water gel bath is replaced to continue soaking for 6-8 hours and then taken out, and the obtained product is placed in room-temperature dust-free air to be naturally dried and then used as waterproof and antibacterial outer-layer base cloth for later use.

Further, according to the preparation process of the waterproof and antibacterial composite fiber fabric for medical products, the antibacterial agent is one or a combination of more of thymol, oregano oil, artemisia oil, carvacrol, forsythia oil, citronella oil and wormwood essential oil; the heat conducting particles are dopamine modified boron nitride.

The antibacterial agent is a natural antibacterial substance, and is safe, nontoxic, good in biocompatibility and high in antibacterial efficiency. The dopamine modified boron nitride is obtained by modifying the surface of hexagonal boron nitride through the oxidative autopolymerization characteristic of dopamine, so that a compact coating film is formed on the surface of the hexagonal boron nitride by the polydopamine, and an active group is 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:

。

further, in the preparation process of the waterproof and antibacterial composite fiber fabric for medical products, in the step S4, a PCL adhesive film is sprayed on one surface of an antibacterial inner layer base fabric, the antibacterial inner layer base fabric is covered on the roller for a circle, and the PCL adhesive film is arranged on the surface facing outwards, and then the heat-conducting spinning solution is subjected to ultrasonic treatment for 10-30min, and then the heat-conducting composite fiber film is obtained by spinning on the antibacterial inner layer base fabric covered with the PCL adhesive film through an electrostatic spinning machine; and S5, spraying a PCL bonding film on one surface of the waterproof and antibacterial outer-layer base cloth opposite to the waterproof film layer, compounding the waterproof and antibacterial outer-layer base cloth and the antibacterial inner-layer base cloth coated with the heat-conducting composite fiber film into a whole through a hot rolling press, and arranging the waterproof film layer of the waterproof and antibacterial outer-layer base cloth outwards.

The PCL bonding films are arranged 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, so that 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 and antibacterial composite fiber fabric for medical products, in S4, the parameters of the electrostatic spinning machine are set as follows: the positive voltage is 20-30 KV, the negative voltage is 1-5KV, the push injection speed of the heat-conducting spinning solution is 0.05-0.2mm/min, the distance from a needle to a roller is fixed to be 10-30cm, the translation speed of an electrostatic spinning machine is 300-600mm/min, and the rotation speed of the received roller is 100-200rpm/min; in S5, the parameters of the hot-roll hot press are set as follows: the hot rolling and 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 transmission rate are provided. By heating and pressurizing through hot rolling and hot pressing, PLA and PCL of the antibacterial inner layer base cloth, the waterproof antibacterial outer layer base cloth and the heat-conducting composite fiber membrane are melted and consolidated to form a more stable structure.

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

the spunlace mechanism comprises a net curtain, a plurality of guide rollers, a plurality of spunlace heads and a plurality of negative pressure suction dehydrators; the net curtain is of an annular structure, is sleeved on the guide rollers, and is rotated by the guide rollers to form annular conveying of the net curtain so as to support the fiber net; a plurality of water stabs are uniformly distributed above the net curtain, a plurality of negative pressure suction dehydrators are uniformly distributed below the net curtain, and the water stabs and the negative pressure suction dehydrators are vertically and correspondingly arranged;

spunlace return water treatment mechanism, including gas-water separator, return water collecting pit, sand filtration pond group, clean water basin, metal filter, high-pressure pump, the import of negative pressure suction dehydrator's export, gas-water separator, return water collecting pit, sand filtration pond group, clean water basin, metal filter, high-pressure pump, spunlace head is passed through the pipeline and is connected gradually.

The operating principle of the spunlace mechanism is as follows: the net curtain and a plurality of guide rollers support the fiber net to move, high-pressure water flow pressurized by a high-pressure pump continuously sprays the fiber net below from the spunlace heads, and fibers in the fiber net move and displace to rearrange and intertwine with each other under the impact action of water needles, so that the fiber net is reinforced. During the spunlace process, the retained water in the fiber web is absorbed by the negative pressure suction dewaterers, so that the fiber entanglement effect in the subsequent spunlace process can be avoided being influenced, and the subsequent drying of the fiber web is facilitated.

The water consumption of the spunlace mechanism is very large, generally between 50 and 500t/h, and if the spunlace mechanism cannot be utilized, the water is greatly wasted, but the water after the spunlace process contains fiber oiling agents, various fiber short scraps, microfibril separated from fibers, cellulose aggregates and other impurities, and if the impurities are not treated, the impurities flow back to the spunlace head, so that a spunlace plate of the spunlace head is blocked, pinholes of the spunlace plate are abraded and deformed, and the quality of a fiber web is influenced. By arranging the spunlace backwater treatment mechanism, adopting the water treatment method of the sand filter bank-metal filter and utilizing the sand filter bank to perform mechanical separation, filtration, adsorption and contact coagulation on impurities in the water after the spunlace process, the cost is low, and the recovery rate of the water for the spunlace process is increased.

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

Further, in the process for preparing the waterproof antibacterial composite fiber fabric for medical products, the sand filter group of the S1 hydro-entangled machine comprises:

the sand filter tank is of a double-chamber structure and comprises 2 sand filter chambers, and 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;

the sand filter, the back-flushing sedimentation tank and the backwater collecting tank are connected in sequence through pipelines.

The sand filter group comprises a sand filter tank and a backwashing sedimentation tank, so that two processes of filtering and backwashing can be alternately carried out, the water outlet is blocked when the water level rises to a certain height along with excessive impurity deposition and excessive resistance of the sand filter tank, the sand filter tank is backwashed at the moment, the backwashing water flows to the backwashing sedimentation tank, a large amount of suspended matters in the backwashing water are precipitated and released firstly under the action of a flocculating agent of the backwashing sedimentation tank and then discharged into a backwater collecting tank, and thus, the filtering period of the sand filter tank can be prolonged, and the subsequent maintenance cost is reduced.

The sand filter chamber adopts a double-chamber structure and comprises 2 sand filter chambers, one sand filter chamber can be backwashed during backwashing, and the other sand filter chamber can be continuously used for filtering, so that the sand filter chambers can continuously work.

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

Further, in the process for preparing the waterproof antibacterial composite fiber fabric for medical products, the sand filter group further comprises a water jet machine S1:

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

a water inlet channel;

the water inlet of the backwater collecting pool, the water inlet pipe, the water inlet channel, the water drainage tank and the sand filtering chamber are connected in sequence;

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

backwashing the water inlet pipe;

the back washing outlet pipe, the back washing inlet pipe, the drainage tank, the water inlet channel, the back washing outlet pipe of the sand filter chamber and the water inlet of the back washing sedimentation tank are connected in sequence; the back-washing water inlet pipe is provided with a back-washing water inlet valve, and the back-washing water outlet pipe is provided with a back-washing water outlet valve.

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

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

(2) The invention discloses a waterproof and antibacterial composite fiber fabric for medical products, which is characterized in that an antibacterial inner layer base fabric and a waterproof and antibacterial outer layer base fabric are prepared by taking degradable materials such as China hemp fibers, viscose fibers and PLA fibers as raw materials through a spunlace method, and the advantages of the China hemp fibers, the viscose fibers and the PLA fibers are combined; the base cloth is subjected to microcapsule antibacterial finishing, the antibacterial microcapsules are stably and uniformly distributed and fixed on the base cloth, and the slow release performance of the antibacterial microcapsules can enable the antibacterial agent embedded in the antibacterial microcapsules 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 microcapsules can be protected; the surface of the semi-finished product of the waterproof and antibacterial outer-layer base cloth, which faces outwards, is subjected to waterproof finishing, and is solidified into a waterproof film layer with the aperture of 85-95 mu m under the pore-forming and nucleating effects of azodicarbonamide and the activating effect 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 film layer is between the diameters of water vapor molecules and liquid water drop molecules and the dispersibility of pores is good;

(3) The invention discloses a preparation process of a waterproof and antibacterial composite fiber fabric for medical products, wherein a heat-conducting composite fiber membrane is arranged between an antibacterial inner layer base fabric and a waterproof and antibacterial outer layer base fabric, the heat-conducting composite fiber membrane takes degradable materials such as PLA and PCL as raw materials and is doped with heat-conducting particles, the heat-conducting particles are uniformly loaded on the heat-conducting composite fiber membrane by an electrostatic spinning technology and are internally constructed into an interconnected heat-conducting frame, and the composite fiber fabric generates a cooling effect in a heat conduction mode, so that the heat-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 spunlace backwater in the preparation process, wherein the retained water in a fiber net is absorbed by a plurality of negative pressure suction dehydrators in the spunlace process, so that the fiber entanglement effect in the subsequent spunlace process is avoided, the subsequent drying of the fiber net is facilitated, the water sucked by the negative pressure suction dehydrators is treated by a spunlace backwater treatment mechanism and then flows back to a spunlace head for recycling, the spunlace backwater treatment mechanism adopts a water treatment method of a sand filter bank-metal filter, impurities in a water body are subjected to mechanical separation, adsorption and contact coagulation by using the sand filter bank, the two processes of filtration and backwashing of the sand filter bank can be alternately carried out, the filtration period of the sand filter bank is prolonged, the cost is low, and the recycling rate of the spunlace process water is improved.

Drawings

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

FIG. 2 is a structural schematic diagram II of a waterproof antibacterial composite fiber fabric for medical products according to the invention;

FIG. 3 is an overall layout view of a spunlace machine used for S1 in the manufacturing process of the waterproof and antibacterial composite fiber fabric for medical products according to the invention;

FIG. 4 is a schematic connection diagram of a water-jet back-water treatment mechanism of a water-jet machine used for S1 in the preparation process of the waterproof and antibacterial composite fiber fabric for medical products;

FIG. 5 is a sectional view of a sand filter group of a spunlace machine used for S1 in the process for preparing the waterproof and antibacterial composite fiber fabric for medical products according to the invention;

FIG. 6 is a graph showing the sustained-release profiles of the antibacterial microcapsules of examples 2 to 4 of the present invention;

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

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below in examples 1, 2 to 4, comparative examples 1 and 5, comparative examples 2 to 4 and 6 to 7, and examples 8 to 10, in conjunction with specific experimental data and accompanying drawings 1 to 6, and it is apparent that the described embodiments are only a part of the embodiments of the present invention, but not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The following example 1 provides a base fabric and a process for preparing the same.

The fiber raw materials used in example 1 were all commercially available, and their specifications and properties are shown in table 1.

TABLE 1 specification and Properties of fiber raw materials

Example 1

Mixing China hemp fibers, viscose fibers and PLA fibers according to the weight ratio of 50:35:15, opening by an opener, carding by a carding machine to obtain a fiber web, reinforcing the fiber web by a spunlace machine, and naturally drying to obtain the embodiment 1.

The mechanical properties of the base fabric obtained in example 1 were measured by the following test methods, and the results are shown in Table 2.

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

(2) Bursting strength: reference is made to GB/T24218.5-2016.

(3) Tearing strength: refer to FZ/T60006-91.

Table 2 mechanical properties test results of example 1

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The following examples 2-4 provide a process for the preparation of antimicrobial microcapsules and antimicrobial inner layer base fabrics.

The raw materials adopted in examples 2-4 are sodium alginate, chitosan quaternary ammonium salt, calcium chloride, tween-80 emulsifier, wormwood essential oil, wormwood oil, carvacrol, 2D resin and MgCl ₂ And JFC penetrant is all sold in the market.

Example 2

Preparation of the antibacterial microcapsules of example 2, comprising the steps of:

(1) Respectively preparing a sodium alginate solution with the mass fraction of 2%, a chitosan quaternary ammonium salt aqueous solution with the mass fraction of 1% and a calcium chloride solution with the mass fraction of 6%;

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

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

(4) Slowly dropwise adding a calcium chloride solution into the wormwood essential oil/sodium alginate emulsion/chitosan quaternary ammonium salt emulsion, wherein the adding 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) And (3) centrifugally washing the antibacterial microcapsule suspension for 3-5 times, and freeze-drying for 12 hours to obtain the antibacterial microcapsule of example 2.

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

the antibacterial finishing liquid comprises: 125 g/L of 2D resin, 55g/L of the antibacterial microcapsule of example 2, and MgCl ₂ 15 An antibacterial finishing liquid is prepared according to a formula of 1.0 g/L of a JFC penetrant, and the base fabric of example 1 is immersed in the antibacterial finishing liquid at a bath ratio of 1:30, the dipping temperature is 40 ℃, the dipping time is 1.5 h, the baking is carried out for 3 min at the temperature of 60 ℃, and the air drying is carried out naturally to obtain the antibacterial inner layer base fabric of the embodiment 2.

Example 3

The preparation of the antibacterial microcapsule of example 3, comprising the following steps:

(1) Respectively preparing a sodium alginate solution with the mass fraction of 1.5%, a chitosan quaternary ammonium salt aqueous solution with the mass fraction of 0.75% and a calcium chloride solution with the mass fraction of 5%;

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

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

(4) Slowly dropwise adding a calcium chloride solution into the artemisia argyi oil/sodium alginate emulsion/chitosan quaternary ammonium salt emulsion, wherein the adding 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) And (3) centrifugally washing the antibacterial microcapsule suspension for 3-5 times, and freeze-drying for 12 hours to obtain the antibacterial microcapsule of example 3.

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

the antibacterial finishing liquid comprises: 125 g/L of 2D resin, 55g/L of the antibacterial microcapsule of example 3, mgCl ₂ 15 An antibacterial finishing liquid is prepared by a formula of 1.0 g/L of JFC penetrant, and the base fabric of the embodiment 1 is immersed into the antibacterial finishing liquid, wherein the bath ratio is 1:30, the dipping temperature is 40 ℃, the dipping time is 1.5 h, the mixture is baked for 3 min at the temperature of 60 ℃ and naturally dried, and the antibacterial inner layer base fabric of the embodiment 3 is obtained.

Example 4

Preparation of the antibacterial microcapsules of example 4, comprising the steps of:

(1) Respectively preparing a sodium alginate solution with the mass fraction of 1.5%, a chitosan quaternary ammonium salt aqueous solution with the mass fraction of 0.75% and a calcium chloride solution with the mass fraction of 6%;

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

(3) Slowly dripping the carvacrol/sodium alginate emulsion into the chitosan quaternary ammonium salt aqueous solution by taking the chitosan quaternary ammonium salt aqueous solution with the volume 3 times of that of the sodium alginate aqueous solution, stirring at the speed of 1200r/min, adjusting the pH to 5-6 after finishing dripping, continuously stirring at the speed of 1200r/min, and stirring for 30min to obtain the 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 adding amount of the calcium chloride solution is 40% of the volume of the sodium alginate aqueous solution, and reacting for 2.5 hours in a water bath at 50 ℃ to obtain an antibacterial microcapsule suspension;

(5) And (3) centrifugally washing the antibacterial microcapsule suspension for 3-5 times, and freeze-drying for 12 hours to obtain the antibacterial microcapsule of example 4.

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

the antibacterial finishing liquid comprises: 125 g/L of 2D resin, 55g/L of the antibacterial microcapsule of example 4, mgCl ₂ 15 An antibacterial finishing liquid is prepared by a formula of 1.0 g/L of JFC penetrant, and the base fabric of the embodiment 1 is immersed into the antibacterial finishing liquid, wherein the bath ratio is 1:30, the dipping temperature is 40 ℃, the dipping time is 1.5 h, the baking is carried out for 3 min at the temperature of 60 ℃, and the air drying is carried out naturally to obtain the antibacterial inner layer base fabric of the embodiment 4.

The antibacterial microcapsules prepared in the above examples 2 to 4 were tested for encapsulation efficiency, drug loading rate, yield, and sustained release property (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 dry antibacterial microcapsule, placing the microcapsule in 100 mL of absolute ethyl alcohol, uniformly stirring, carrying out ultrasonic oscillation at 50 ℃ for 40min in an ultrasonic cleaning machine, then placing the microcapsule in a constant-temperature water bath shaking table at the temperature of 150 r/min and 37 ℃ for oscillation for 24h, placing the microcapsule in the ultrasonic cleaning machine at the temperature of 50 ℃ for ultrasonic oscillation for 40min every 8h, fully releasing the antibacterial agent in the antibacterial microcapsule, carrying out vacuum filtration on the mixed solution, centrifuging the obtained filtrate for 20min on a high-speed centrifuge, taking out the supernatant, and measuring the absorbance of the obtained liquid at the maximum absorption wavelength by using an ultraviolet visible spectrophotometer. And (4) bringing the absorbance value into an antibacterial agent-ethanol standard curve to obtain the concentration of the antibacterial agent in the liquid. And calculating the content of the antibacterial agent in the antibacterial microcapsule by combining the volume of the liquid. Then, the encapsulation efficiency, drug loading efficiency, and yield were calculated by the following formulas, respectively.

Entrapment rate = mass of antibacterial agent/mass of antibacterial agent put in the antibacterial microcapsule × 100%;

drug loading rate = mass of antibacterial agent in antibacterial microcapsule/mass of antibacterial microcapsule × 100%;

yield = mass of antibacterial microcapsule/total mass of input raw materials × 100%.

Table 3 test results of the antibacterial microcapsules of examples 2 to 4

As can be seen from table 3 and fig. 6, the antibacterial microcapsules of examples 2 to 4 prepared by the preparation process of the present invention all have high encapsulation efficiency, drug loading rate, and yield, and also have good sustained release performance.

The antibacterial inner layer base fabrics prepared in the above examples 2 to 4 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 property: the antibacterial performance of the antibacterial inner layer base cloth prepared in the example 2-4 was tested by the oscillating flask method, and the strains were gram-negative bacteria escherichia coli and gram-positive bacteria staphylococcus aureus.

(2) Air permeability: reference is made to GB/T24218-2009.

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

Table 4 test results of antibacterial inner layer base fabrics of examples 2 to 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 had excellent antibacterial properties and air and moisture permeability, and the antibacterial inner layer base fabric of example 4 was considered to be the most excellent.

The following comparative example 1 and example 5 provide a waterproof antibacterial outer layer base fabric and a preparation process thereof.

The starting materials DMF, polybutylene adipate/terephthalate, azodicarbonamide and ZnO used in comparative example 1 and example 5 are all commercially available.

Comparative example 1

The preparation of the waterproof and antibacterial outer-layer base fabric of the comparative example 1 comprises the following steps: dissolving poly (butylene adipate/terephthalate) in DMF to prepare a poly (butylene adipate/terephthalate) solution with the solid content of 20%, scraping the poly (butylene adipate/terephthalate) solution on the antibacterial inner-layer base fabric of the example 4 by a film coater to form a waterproof film layer 21 with the thickness of 60 microns, naturally standing for 2 hours, then soaking in a pure water gel bath for 6 hours at room temperature, taking out, replacing the pure water gel bath, continuously soaking for 6 hours, taking out, naturally airing in room-temperature dust-free air to obtain the waterproof antibacterial outer-layer base fabric of the comparative example 1.

Example 5

The preparation of the waterproof and antibacterial outer-layer base fabric of the embodiment 5 comprises the following steps: dissolving polybutylene adipate/terephthalate in DMF to prepare a polybutylene adipate/terephthalate solution with the solid content of 20%, and mixing the polybutylene adipate/terephthalate solution, azodicarbonamide and ZnO according to the mass ratio of 100:1:1 to obtain a waterproof finishing liquid, scraping the waterproof finishing liquid on the antibacterial inner layer base cloth of the embodiment 4 by a film coater to form a waterproof film layer 21 with the thickness of 60 microns, naturally placing the waterproof film layer for 2 hours, then soaking the waterproof film layer in a pure water gel bath, taking out the waterproof finishing liquid after soaking the waterproof film layer for 6 hours at room temperature, replacing the pure water gel bath for continuous soaking for 6 hours, taking out the waterproof finishing liquid, and naturally airing the waterproof finishing liquid in dustless air at room temperature to obtain the waterproof antibacterial outer layer base cloth of the embodiment 5.

The waterproof and antibacterial outer base fabrics obtained in comparative example 1 and example 5 were tested for water repellency, air permeability, moisture permeability and pore size according to the following test methods, and the test results are shown in Table 5.

(1) Water resistance: the water repellency was judged by measuring the surface contact angle of the water-repellent film layers of comparative example 1 and example 5 with a contact angle measuring instrument.

(2) Air permeability: reference is made to GB/T24218-2009.

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

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

TABLE 5 test results of comparative example 1 and example 5

As can be seen from table 5, the pore diameters of comparative example 1 and example 5 are between the diameters of the water vapor molecules and the liquid water droplets, and have better water resistance, but under the pore-forming and nucleation effects of azodicarbonamide and the activation effect of ZnO, example 5 can form a more uniform open pore structure, 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 starting materials PLA, PCL and hexagonal boron nitride (10 μm in radial dimension) used in comparative examples 2 to 4 and examples 6 to 7 were all commercially available.

Comparative example 2

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

Comparative example 3

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

(1) PLA and PCL are mixed according to the proportion of 90:10, dissolving the mixture in a solvent (mixed solvent of trichloromethane and DMF, the mass ratio is 7; wherein the parameters of the electrostatic spinning machine are as follows: the positive voltage is 25KV, the negative voltage is 2KV, the injection speed of the heat-conducting spinning solution is 0.08mm/min, the distance from a needle head to a roller is fixed to be 15cm, the translation speed of the electrostatic spinning machine is 400mm/min, and the rotating speed of a received roller is 150rpm/min;

(2) The waterproof and antibacterial outer base fabric of example 5 and the antibacterial inner base fabric coated with the composite fiber membrane are compounded into a whole through a hot rolling hot press to obtain the composite fiber fabric of comparative example 3, and one side of the waterproof membrane layer of the waterproof and antibacterial outer base fabric is arranged outwards. Wherein, the parameters of the hot rolling hot press are set as follows: the hot rolling bonding 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, includes an antibacterial inner layer base fabric 1, a waterproof antibacterial outer layer base fabric 2, and a heat conductive composite fiber membrane 3, and the antibacterial inner layer base fabric 1, the heat conductive composite fiber membrane 3, and the waterproof antibacterial outer layer base fabric 2 are sequentially stacked and hot-pressed and compounded into a whole.

The preparation of the composite fiber fabric of comparative example 4, comprising the steps of:

(1) PLA, PCL and hexagonal boron nitride are mixed according to the proportion of 89:9:2, dissolving the mixture in a solvent (a mixed solvent of trichloromethane and DMF, the mass ratio is 7; wherein the parameters of the electrostatic spinning machine are as follows: the positive voltage is 25KV, the negative voltage is 2KV, the injection speed of the heat-conducting spinning solution is 0.08mm/min, the distance from a needle head to a roller is fixed to be 15cm, the translation speed of the electrostatic spinning machine is 400mm/min, and the rotating speed of a received roller is 150rpm/min;

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

Example 6

The composite fiber fabric of embodiment 6, as shown in fig. 1, includes an antibacterial inner layer base fabric 1, a waterproof antibacterial outer layer base fabric 2, and a heat-conductive composite fiber membrane 3 (one surface is provided with a waterproof film layer 21), and the antibacterial inner layer base fabric 1, the heat-conductive composite fiber membrane 3, and the waterproof antibacterial outer layer base fabric 2 are sequentially stacked and hot-pressed and combined into a whole.

The preparation of the composite fiber fabric of example 6, comprising the steps of:

(3) PLA, PCL and dopamine modified boron nitride are mixed according to the proportion of 89:9:2, dissolving the mixture in a solvent (a mixed solvent of trichloromethane and DMF, the mass ratio is 7; wherein the parameters of the electrostatic spinning machine are set as follows: the positive voltage is 25KV, the negative voltage is 2KV, the injection speed of the heat-conducting spinning solution is 0.08mm/min, the distance from a needle head to a roller is fixed to be 15cm, the translation speed of the electrostatic spinning machine is 400mm/min, and the rotating speed of a received roller is 150rpm/min;

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

Example 7

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

The preparation of the composite fiber fabric of example 7, comprising the steps of:

(1) PLA, PCL and dopamine modified boron nitride are mixed according to the proportion of 89:9:2, dissolving the mixture in a solvent (a mixed solvent of trichloromethane and DMF, the mass ratio is 7; wherein the parameters of the electrostatic spinning machine are as follows: the positive voltage is 25KV, the negative voltage is 2KV, the injection speed of the heat-conducting spinning solution is 0.08mm/min, the distance from a needle to a roller is fixed to be 15cm, the translation speed of the electrostatic spinning machine is 400mm/min, and the rotating speed of the received roller is 150rpm/min;

(2) A PCL adhesive film a (20 μm thick) is sprayed on the opposite side of the waterproof film layer 21 of the waterproof and antibacterial outer base fabric 2, and the PCL adhesive film a and the antibacterial inner base fabric 1 coated with the heat-conducting composite fiber film 3 are combined into a whole by a hot-rolling hot press to obtain the composite fiber fabric of example 7, and the waterproof film layer 21 of the waterproof and antibacterial outer base fabric 2 faces outward. Wherein the parameters of the hot rolling hot press are set as follows: the hot rolling bonding speed is 2.5r/min, and the heat treatment temperature is 90 ℃.

The dopamine modified boron nitride used in examples 6 to 7 is obtained 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 filtration resistance, 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 filtration performance: and testing the protective filtering performance by adopting a TSI8130A automatic filter material tester. The composite fiber fabric was cut into a circle having a diameter of 30cm, and the filtration efficiency was measured at an air flow rate of 15L/min.

(2) Air permeability: reference is made to GB/T24218-2009.

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

(4) Antibacterial property: the shaking flask method was used.

(5) Heat conductivity: the thermal conductivity is tested with reference to the ISO22007 standard.

TABLE 6 test results of comparative examples 2 to 4 and examples 6 to 7

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 requirements of the medical disposable protective clothing of the national standard GB19082-2009, and the requirements are met.

Compared with comparative example 2, comparative examples 3 to 4 and examples 6 to 7 have certain influence on the air permeability and the moisture permeability of the composite fiber fabric because 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, in comparative example 4 and examples 6 to 7, the hexagonal boron nitride or dopamine modified boron nitride is doped in the heat-conducting composite fiber membrane, so that the porosity of the heat-conducting composite fiber membrane is increased, and the increased gaps and channels are more favorable for air flow to pass through, so that the air permeability and the moisture permeability are improved.

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

The composite fiber fabric of example 6 is most suitable for comprehensive consideration, 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 bonding film, but the addition of the PCL bonding film can reduce the problems of easy separation between layers and poor mechanical properties of the composite fabric.

In addition, the invention also relates to equipment used in the preparation process of the waterproof and antibacterial composite fiber fabric for the medical product, namely a spunlace machine, and the invention is further illustrated by combining the attached figures 3-5 and the specific examples 8-10.

Example 8

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

After being pressurized by a high-pressure pump 56, water is continuously sprayed from a water jet head 43 onto a pre-wetted fiber net b supported by a net curtain 41 and a plurality of guide rollers 42, a plurality of strands of fine water jets sprayed from a water needle board needle of the water jet head 43 vertically shoot towards the fiber net b, so that part of surface fibers in the fiber net b are displaced, and after penetrating through the fiber net b, the water jets are subjected to the rebound effect of the surface of the net curtain 41 and are scattered to the reverse side of the fiber net b in different directions. Under the dual action of direct impact of water jet and rebounding water flow, the fibers in the fiber web b are displaced, interpenetrated, tangled and cohered to form an infinite number of flexible intertwining points, so that the fiber web is reinforced to form a stable intertwining structure. In the spunlace process, the retained water in the fiber web b is absorbed by a plurality of negative pressure suction dehydrators 44, the water sucked by the negative pressure suction dehydrators 44 is separated by a gas-water separator 51 of a spunlace backwater treatment mechanism 5, collected by a backwater collecting tank 52, filtered by a sand filter tank group 53, reserved by a clean water tank 54, finely filtered by a metal filter 55 and pressurized by a high-pressure pump 56, fiber oiling agents, various fiber short scraps, microfibril fibers, cellulose aggregates and other impurities separated from the fibers are removed, and the water flows back to the spunlace head 43, so that the phenomena of blockage of a water needle plate of the spunlace head 43 and abrasion deformation of the needle plate needle hole are avoided, the stripes of the fiber web b caused by the blockage are reduced, the spunlace effect is ensured, and the water resource is saved.

Example 9

Based on the above structural basis of embodiment 8, as shown in fig. 3, 4 and 5.

In the spunlace machine, the sand filter 531 is in a double-chamber structure, namely 2 sand filter chambers 5311, a filter material layer 5312, a padding material layer 5313 and a drainage system 5314 are arranged in each sand filter chamber 5311 from top to bottom, so that one sand filter chamber 5311 can be backwashed during backwashing, and the other sand filter chamber 5311 can be continuously used for filtering, so that the sand filter 531 can continuously work.

Example 10

Based on the above structural basis of embodiment 8 or embodiment 9, as shown in fig. 3, 4 and 5.

According to the spunlace machine, the sand filter tank group 53 comprises the sand filter tank 531 and the backwashing sedimentation tank 532, the two processes of filtering and backwashing can be alternately performed due to the design of the sand filter tank 531 and the backwashing sedimentation tank 532, the discharged water is blocked when the water level rises to a certain height along with excessive impurity deposition and excessive resistance of the sand filter tank 531, the backwashing water is backwashed on the sand filter tank 531, the backwashing water flows to the backwashing sedimentation tank 532, a large amount of suspended matters in the backwashing water are precipitated and released under the action of a flocculating agent of the backwashing sedimentation tank 532 and then are discharged into the backwater collecting tank 52, and therefore the filtering period of the sand filter tank 531 can be prolonged.

Specifically, the method comprises the following steps: the water body after the water stabbing is subjected to gas-water separation by the gas-water separator 41, is distributed into the sand filter chamber 5311 from the water inlet pipe 533 through the water inlet channel 534 and the water discharge groove 535, passes through the filter material layer 5312 and the padding layer 5313 from top to bottom in the sand filter chamber 5311, is collected by the water discharge system 5314, and is discharged into the clean water tank 54 through the water discharge pipe 536, and during the operation, the sand filter chamber 5311 is in a fully submerged state. The resistance is increased along with the gradual deposition of impurities on the filter material layer 5312, so that the water level is increased, when the water level is increased to a certain height, the water outlet is blocked, and the sand filter chamber 5311 is backwashed at the moment. During backwashing, the water inlet valve of the water inlet pipe 533 and the water outlet valve of the water outlet pipe 536 are closed, the backwashing water inlet valve of the backwashing water inlet pipe 537 and the backwashing water outlet valve of the backwashing water outlet pipe 538 are opened, and backwashing water passes through the water discharge system 5314, the padding layer 5313 and the filter layer 5312 from bottom to top, is collected by the water discharge tank 535, and is discharged to the backwashing sedimentation tank 532 through the water inlet channel 534 and the backwashing water outlet pipe 538.

The specific preparation process routes of the invention are many, and the above description is only the 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 various modifications can be made without departing from the spirit of the invention, and these modifications should be construed as within the scope of the invention.

Claims

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

s2: soaking the base cloth in the antibacterial finishing liquid for 0.5-2h, baking for 1-5min, and naturally drying, wherein one part of the base cloth is used as an antibacterial inner layer base cloth (1), and the other part of the base cloth is used as a waterproof antibacterial outer layer base cloth semi-finished product; the antibacterial finishing liquid comprises: 120-130g/L of 2D resin, 50-60g/L of antibacterial microcapsule and MgCl ₂ 10-20g/L and 0.5-1.5g/L of JFC penetrant;

s3: scraping the waterproof finishing liquid on the semi-finished product of the waterproof and antibacterial outer-layer base cloth through a film coater to form a waterproof film layer (21) with the thickness of 50-500 microns, naturally standing for 1-2 hours, then soaking in a pure water gel bath for 12-24 hours at room temperature, and naturally airing to obtain the 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 a polybutylene adipate/terephthalate solution, 0.5-2 parts of azodicarbonamide and 0.1-0.5 part of ZnO; the solution of poly (butylene adipate/terephthalate) is prepared by dissolving poly (butylene adipate/terephthalate) in DMF, and the solid content is 10-30%;

s4: PLA, PCL and heat conducting particles are mixed according to the proportion of 80-90:8-12:2-4, dissolving in a solvent, continuously stirring at 70-80 ℃ for 5-6h to prepare a heat-conducting spinning solution with the concentration of 5-15wt%, covering the antibacterial inner-layer base cloth (1) on a roller for a circle, performing ultrasonic treatment on the heat-conducting spinning solution for 10-30min, 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 and antibacterial outer-layer base cloth (3) and the antibacterial inner-layer base cloth (1) covered with the heat-conducting composite fiber membrane (3) are compounded into a whole through a hot rolling hot press, and one side of a waterproof membrane layer (21) of the waterproof and antibacterial outer-layer base cloth (2) faces outwards.

2. The process for preparing the 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 and antibacterial outer 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 stacked and are combined into a whole through hot pressing.

3. The preparation process of the waterproof and antibacterial composite fiber fabric for the medical product according to claim 1, wherein in the step S2, the base fabric is immersed in the antibacterial finishing liquid at a bath ratio of 1:20-40 deg.C, soaking at 30-50 deg.C, and baking at 50-70 deg.C for 1-5min; the antibacterial microcapsules in the antibacterial finishing liquid are of a spherical structure, and the average grain diameter 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 preparation process of the waterproof antibacterial composite fiber fabric for the medical product according to claim 1, wherein the preparation of the antibacterial microcapsule comprises the following steps:

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

(3) Taking a chitosan quaternary ammonium salt aqueous solution with the volume 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, simultaneously stirring at the speed of 1200-1500r/min, adjusting the pH to 5-6 after finishing 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 adding amount of the calcium chloride solution is 30-50% of the volume of the sodium alginate solution, and reacting for 2-3h in a water bath at 30-60 ℃ to obtain an antibacterial microcapsule suspension;

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

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

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

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

the spunlace mechanism (4) comprises a net curtain (41), a plurality of guide rollers (42), a plurality of spunlace heads (43) and a plurality of negative pressure suction dehydrators (44); the net curtain (41) is of an annular structure, is sleeved on the guide rollers (42), and forms annular conveying of the net curtain (41) through rotation of the guide rollers (42) to support the fiber net; a plurality of water stabs (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 stabs (43) and the negative pressure suction dehydrators (44) are vertically and correspondingly arranged;

spunlace backwater treatment mechanism (5), including moisture separator (51), return water collecting pit (52), sand filter group (53), clean water basin (54), metal filter (55), high-pressure pump (56), the export of negative pressure suction dehydrator (44), moisture separator (51), return water collecting pit (52), sand filter group (53), clean water basin (54), metal filter (55), high-pressure pump (56), the import of spunlace head (43) are passed through the pipeline and are connected gradually.

9. The process for preparing a waterproof and antibacterial composite fiber fabric for medical products according to claim 8, wherein the sand filtration unit (53) comprises a hydro-entangling machine for S1:

the sand filter (531), the sand filter (531) is a double-chamber structure, comprising 2 sand filter chambers (5311), and a filter material layer body (5312), a padding layer body (5313) and a drainage system (5314) are arranged in each sand filter chamber (5311) 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;

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

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

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

an inlet channel (534);

the water inlet of the water return collecting tank (52), the water inlet pipe (533), the water inlet channel (534), the water discharge tank (535) and the sand filter chamber (5311) are connected in sequence;

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

a backwash water inlet pipe (537);

the backwashing water outlet pipe (538), the backwashing port of the sand filter chamber (5311), the backwashing water inlet pipe (537), the water discharge tank (535), the water inlet channel (534), the backwashing water outlet pipe (538) and the water inlet of the backwashing sedimentation tank (532) are connected in sequence; the backwashing water inlet pipe (537) is provided with a backwashing water inlet valve, and the backwashing water outlet pipe (538) is provided with a backwashing water outlet valve.