Medical drawsheet with high air permeability and moisture permeability and preparation process of medical drawsheet

Abstract

The invention relates to the technical field of medical nursing products, in particular to a medical drawsheet with high air permeability and moisture permeability and a preparation process thereof. The preparation method comprises the following steps: soaking a non-woven fabric in a tannic acid solution to obtain a hydrophilic non-woven fabric; the non-woven fabric is sequentially soaked in a dopamine buffer solution and mercaptopropyl methyl dimethoxy silane, and the modified super-hydrophilic non-woven fabric is obtained. The preparation method comprises the following steps: adding acrylic acid, a sodium hydroxide solution, trimethylolpropane triacrylate, a propenyl modified chitosan antibacterial material, potassium persulfate, sodium hydrogen sulfite and lauryl sodium sulfate to obtain super absorbent resin; and laying and forming the super absorbent resin to obtain the absorption layer. The absorption layer, the modified super-hydrophilic non-woven fabric and the hydrophilic non-woven fabric sequentially cover the impermeable layer and are subjected to hot-pressing bonding through a hot melt adhesive, and the medical drawsheet with the high air permeability and moisture permeability is obtained. The medical drawsheet prepared by the invention has high air and moisture permeability and good antibacterial property, so that the medical drawsheet has a wide application prospect in the technical field of medical nursing products.

Description

Technical Field

[0001] The present invention relates to the technical field of medical care products, and particularly to a highly breathable and moisture-permeable medical pad sheet and its preparation process. Background Art

[0002] In the modern medical field, medical pad sheets are playing an irreplaceable and important role, demonstrating multi-dimensional modern values. From the perspective of patient experience, medical pad sheets can keep the skin dry, effectively reducing the occurrence probability of skin diseases such as pressure ulcers and eczema. Especially for long-term bedridden patients, this is undoubtedly a key factor in improving the quality of life. In medical care work, the pad sheets reduce the workload of medical staff, enabling them to devote more time and energy to the direct care of patients. At the same time, the pad sheets can effectively prevent liquid penetration, avoid contaminating the hospital bed and the surrounding environment, and reduce the risk of cross-infection, creating a safer and more hygienic treatment environment for patients.

[0003] However, traditional medical pad sheets have poor breathability. When patients use them for a long time, they are prone to feel stuffy and humid, which not only reduces the comfort of patients but may also cause a series of skin problems. For example, a humid environment can soften the cutin layer of the skin, reduce the resistance of the skin, and increase the risk of skin diseases such as pressure ulcers and eczema. A pad sheet with good breathable and moisture-permeable properties can timely discharge the sweat and moisture generated by the human body, keep the skin dry, and effectively reduce the occurrence of these problems, making patients more comfortable during the treatment process and beneficial to the recovery of the body. In addition, hospitals are places where various germs are concentrated, and medical pad sheets are easily contaminated by microorganisms such as bacteria and fungi. If the pad sheets do not have good antibacterial properties, these microorganisms will multiply in large numbers, increasing the risk of patient infection. Antibacterial pad sheets can inhibit the growth of bacteria and fungi, reduce the probability of cross-infection, provide a safer treatment environment for patients, and are of great significance for controlling nosocomial infections.

[0004] In order to overcome the defects of the prior art, the present invention provides a highly breathable and moisture-permeable medical pad sheet and its preparation process. Summary of the Invention

[0005] The purpose of the present invention is to provide a highly breathable and moisture-permeable medical pad sheet and its preparation process to solve the problems in the prior art.

[0006] To solve the above technical problems, the present invention provides the following technical solutions:

[0007] A preparation process of a highly breathable and moisture-permeable medical pad sheet includes the following steps:

[0008] Step 1: Add tris(hydroxymethyl)aminomethane, 0.10 - 0.12 mol / L hydrochloric acid, and deionized water to obtain a buffer solution with pH = 7.8 - 8.0; then add tannic acid to the buffer solution to obtain a tannic acid solution; immerse the non-woven fabric in the tannic acid solution for 15 - 20 h, and after immersion, obtain a hydrophilic non-woven fabric;

[0009] Step 2: Dissolve dopamine in deionized water, then add tris(hydroxymethyl)aminomethane and tris(hydroxymethyl)aminomethane hydrochloride to obtain a dopamine buffer solution with pH = 8.5 - 8.7; immerse the non-woven fabric in the dopamine buffer solution for 10 - 15 h to obtain a superhydrophilic non-woven fabric; then immerse the superhydrophilic non-woven fabric in 3-mercaptopropylmethyldimethoxysilane and react at 90 - 95 °C for 50 - 70 min to obtain a modified superhydrophilic non-woven fabric;

[0010] Step 3: Mix acrylic acid and deionized water, stir well and then dropwise add 48 - 50 wt% sodium hydroxide solution. After neutralization, add trimethylolpropane triacrylate, allyl-modified chitosan antibacterial material, potassium persulfate, sodium bisulfite, and sodium dodecyl sulfate, stir evenly and then heat up to 50 - 60 °C and react for 3 - 5 h. After the reaction, carry out colloid breaking, drying, and pulverizing and sieving to obtain a superabsorbent resin; then lay and form the superabsorbent resin to obtain an absorbent layer;

[0011] Step 4: Cover the absorbent layer, the modified superhydrophilic non-woven fabric, and the hydrophilic non-woven fabric on the anti-seepage layer in sequence, and carry out hot pressing and bonding with hot melt adhesive to obtain a highly breathable and moisture-permeable medical sheet.

[0012] Preferably, in Step 1, in the tannic acid solution, the reaction mass ratio of tris(hydroxymethyl)aminomethane to tannic acid is 12:(5 - 6).

[0013] Preferably, in Step 2, the mass-volume ratio of dopamine to deionized water is (0.004 - 0.005):2.

[0014] Preferably, in Step 3, the component contents of the superabsorbent resin are: by mass parts, 350 - 400 parts of acrylic acid, 470 - 500 parts of deionized water, 240 - 270 parts of sodium hydroxide solution, 3.5 - 4.0 parts of trimethylolpropane triacrylate, 3 - 5 parts of allyl-modified chitosan antibacterial material, 0.7 - 1.0 parts of potassium persulfate, 0.4 - 0.6 parts of sodium bisulfite, and 0.2 - 0.3 parts of sodium dodecyl sulfate.

[0015] Preferably, the preparation process of the allyl-modified chitosan antibacterial material is as follows: Dissolve chitosan and 5-chlorosalicylaldehyde in dimethyl sulfoxide, then add 4A molecular sieve, and stir and react at 60-65 °C for 10-15 h. After the reaction, perform precipitation separation, washing, and freeze-drying to obtain Schiff base chitosan; then mix Schiff base chitosan, inhibitor methylhydroquinone, triethylamine, and tetrahydrofuran, stir until dissolved at 65-75 °C, then dropwise add a tetrahydrofuran solution of acryloyl chloride, and continue to stir and react for 12-14 h. After the reaction, perform liquid separation, washing, filtration, rotary evaporation, and recrystallization to obtain the allyl-modified chitosan antibacterial material.

[0016] Preferably, when preparing Schiff base chitosan, the reaction mass ratio of chitosan, 5-chlorosalicylaldehyde, and 4A molecular sieve is 3:(1.7-2.0):0.7.

[0017] Preferably, when preparing the allyl-modified chitosan antibacterial material, the reaction mass ratio of Schiff base chitosan and acryloyl chloride is 1:(1.0-1.2).

[0018] Preferably, in step three, the laying and forming process parameters are: temperature is 25-35 °C, pressure is 0.3-0.5 MPa, and speed is 5-7 m / min.

[0019] Preferably, in step four, the hot pressing pressure is 2-3 kgf / m 2 ; The hot pressing temperature is divided into two stages: the first stage is heating at 60-70 °C for 1-2 h, and the second stage is heating at 100-150 °C for 2-3 min; The anti-seepage layer is breathable SMS non-woven fabric.

[0020] The beneficial effects of the present invention:

[0021] The characteristics of the present invention are as follows. In step one, the non-woven fabric is impregnated in a tannic acid solution to obtain a hydrophilic non-woven fabric. In step two, the non-woven fabric is successively impregnated in a dopamine buffer solution and 3-mercaptopropylmethyldimethoxysilane to obtain a modified super-hydrophilic non-woven fabric. The structural design of the medical pad of the present invention is that the top layer is a hydrophilic non-woven fabric, the next layer is a modified super-hydrophilic non-woven fabric, and then the absorption layer and the anti-seepage layer. The purpose of this structural design is that when liquid contacts the pad, the hydrophilic layer on the surface can quickly capture the liquid, enabling the liquid to spread rapidly and adhere to the surface, initially guiding the liquid into the interior of the nursing pad. Further, the super-hydrophilic layer in the inner layer has stronger hydrophilicity and can absorb the liquid transferred from the hydrophilic layer at a faster speed. The powerful capillary action of the super-hydrophilic layer will prompt the liquid to spread rapidly in all directions, enabling the absorption materials inside the pad to be utilized more fully, avoiding the accumulation of liquid in a local area, and thus improving the overall absorption capacity. In addition, since the liquid can quickly pass through the hydrophilic layer and enter the super-hydrophilic layer and spread, the surface layer of the pad can return to a dry state more quickly, reducing the contact time between the liquid and the user's skin, lowering the risk of skin discomfort and infection caused by skin dampness, and enhancing the comfort of the user.

[0022] The characteristics of the present invention are as follows. In step three, Schiff base chitosan is obtained by adding chitosan, 5-chlorosalicylaldehyde, and 4A molecular sieve; then, using Schiff base chitosan and acryloyl chloride as the main raw materials, an acryloyl-modified chitosan antibacterial material is prepared. In the process of preparing acryloyl-modified chitosan, Schiff base chitosan is first formed. The C=N double bond in the Schiff base structure has a certain polarity and can interact with the components on the surface of the bacterial cell membrane, destroying the integrity of the cell membrane, resulting in the leakage of intracellular substances, affecting the physiological functions of bacteria, and thus playing an antibacterial role. In addition, the introduction of acryloyl enhances the lipophilicity of chitosan. The enhanced lipophilicity makes the modified chitosan more likely to interact with the bacterial cell membrane, increasing the affinity and penetration ability for the cell membrane, more effectively destroying the bacterial cell membrane, and improving the antibacterial effect. When the modified chitosan penetrates through the cell membrane and enters the bacterial cell, it binds to biological macromolecules such as nucleic acids, interfering with the process of bacterial genetic information transmission and replication. It may also bind to enzymes in the bacteria, changing the structure of the enzyme active center and affecting the bacterial metabolic pathway, inhibiting the growth and reproduction of bacteria.

[0023] A superabsorbent resin is obtained by adding acrylic acid, deionized water, sodium hydroxide solution, trimethylolpropane triacrylate, allyl-modified chitosan antibacterial material, potassium persulfate, sodium bisulfite, and sodium dodecyl sulfate. The superabsorbent resin is laid and shaped to obtain an absorption layer. The superabsorbent resin prepared in the present invention has a network structure formed by the polymerization of acrylic acid, which can accommodate a large amount of water, enabling the medical pad to quickly absorb and lock several times its own weight of liquid, preventing it from leaking onto the bedsheet or clothing and keeping the patient's body and the surrounding environment dry. Secondly, by adding an allyl-modified chitosan antibacterial material, the superabsorbent resin of the present invention also has good antibacterial properties.

[0024] Furthermore, when preparing the superabsorbent resin in the present invention, an excessive amount of acrylic acid is added. Therefore, a certain amount of acrylic acid remains in the prepared absorption layer. When the remaining unreacted acrylic acid in the absorption layer and the modified superhydrophilic non-woven fabric come into contact during the thermocompression reaction in the first stage, a thiol-ene initiation reaction occurs, resulting in a multi-layer structure with good cross-linking. In this step, by carrying out a chemical reaction between the absorption layer and the modified superhydrophilic non-woven fabric, chemical bonds or strong intermolecular forces can be formed at the interface between the absorption layer and the modified superhydrophilic non-woven fabric, making the two layers of materials tightly combined, not easily separated or displaced relatively, and improving the overall structural stability and durability of the medical pad. Moreover, both the absorption layer and the modified superhydrophilic non-woven fabric originally have a certain water absorption capacity. The chemical reaction can form a more abundant pore structure between the two, thereby improving the liquid absorption speed and absorption capacity. Finally, the absorption layer, the modified superhydrophilic non-woven fabric, and the hydrophilic non-woven fabric are successively covered on the anti-seepage layer and hot-pressed and bonded with hot melt adhesive to obtain a highly breathable and moisture-permeable medical pad. The medical pad prepared in the present invention has high breathable and moisture-permeable properties and good antibacterial properties, so it has broad application prospects in the technical field of medical care products. Detailed implementation mode

[0025] Next, the technical solutions in the present invention will be clearly and completely described in combination with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0026] Source of raw materials:

[0027] Chitosan, provided by Qingdao Bozhihuili Biotechnology Co., Ltd., with a deacetylation degree of ≥90% and an industrial-grade specification; 4A molecular sieve, provided by Sinopharm Chemical Reagent Co., Ltd., with a specification of 0.8 mm; breathable SMS non-woven fabric, provided by Shandong Xingdi New Materials Co., Ltd., with the main raw material being PP and a gram weight of 30 g; in terms of mass parts, one part is 1 g.

[0028] Example 1: Step 1: A buffer solution with pH = 8 was obtained by adding tris(hydroxymethyl)aminomethane, 0.1 mol / L hydrochloric acid, and deionized water; then tannic acid was added to the buffer solution to obtain a tannic acid solution; the non-woven fabric was immersed in the tannic acid solution for 20 h, and after the immersion, a hydrophilic non-woven fabric was obtained; in the tannic acid solution, the reaction mass ratio of tris(hydroxymethyl)aminomethane to tannic acid was 12:5.5;

[0029] Step 2: Dopamine was dissolved in deionized water, and then tris(hydroxymethyl)aminomethane and tris(hydroxymethyl)aminomethane hydrochloride were added to obtain a dopamine buffer solution with pH = 8.5; the non-woven fabric was immersed in the dopamine buffer solution for 15 h to obtain a super-hydrophilic non-woven fabric; then the super-hydrophilic non-woven fabric was immersed in 3-mercaptopropylmethyldimethoxysilane and reacted at 95 °C for 70 min to obtain a modified super-hydrophilic non-woven fabric; the mass-volume ratio of dopamine to deionized water was 0.005:2;

[0030] Step 3: Chitosan and 5-chlorosalicylaldehyde were dissolved in dimethyl sulfoxide, and then 4A molecular sieve was added, and the mixture was stirred and reacted at 65 °C for 15 h. After the reaction, precipitation separation, washing, and freeze-drying were carried out to obtain Schiff-base chitosan; then Schiff-base chitosan, inhibitor methylhydroquinone, triethylamine, and tetrahydrofuran were mixed and stirred at 75 °C until dissolved, and then a tetrahydrofuran solution of acryloyl chloride was added dropwise, and the mixture was continuously stirred and reacted for 14 h. After the reaction, liquid separation, washing, filtration, rotary evaporation, and recrystallization were carried out to obtain an acryloyl-modified chitosan antibacterial material; when preparing Schiff-base chitosan, the reaction mass ratio of chitosan, 5-chlorosalicylaldehyde, and 4A molecular sieve was 3:1.8:0.7; when preparing the acryloyl-modified chitosan antibacterial material, the reaction mass ratio of Schiff-base chitosan to acryloyl chloride was 1:1.1;

[0031] 350 g of acrylic acid and 470 g of deionized water were mixed, and after sufficient stirring, 240 g of 50 wt% sodium hydroxide solution was added dropwise. After neutralization, 3.5 g of trimethylolpropane triacrylate, 5 g of acryloyl-modified chitosan antibacterial material, 0.7 g of potassium persulfate, 0.4 g of sodium bisulfite, and 0.2 g of sodium dodecyl sulfate were added. After stirring evenly, the temperature was raised to 60 °C and reacted for 5 h. After the reaction, colloid breaking, drying, and sieving were carried out to obtain a superabsorbent resin; then the superabsorbent resin was laid and formed to obtain an absorption layer; the process parameters for laying and forming: temperature was 35 °C, pressure was 0.5 MPa, and speed was 7 m / min;

[0032] Step 4: The absorption layer, modified super-hydrophilic non-woven fabric, and hydrophilic non-woven fabric were successively covered on the breathable SMS non-woven fabric and hot-pressed and bonded with hot melt adhesive to obtain a highly breathable and moisture-permeable medical sheet; the hot-pressing pressure was 3 kgf / m 2; The hot pressing temperature is divided into two stages: the first stage is heating at 70 °C for 2 h, and the second stage is heating at 150 °C for 3 min.

[0033] Example 2: Step 1: By adding tris(hydroxymethyl)aminomethane, 0.1 mol / L hydrochloric acid, and deionized water, a buffer solution with pH = 8 is obtained; then tannic acid is added to the buffer solution to obtain a tannic acid solution; the non-woven fabric is immersed in the tannic acid solution for 17 h, and after immersion, a hydrophilic non-woven fabric is obtained; in the tannic acid solution, the reaction mass ratio of tris(hydroxymethyl)aminomethane to tannic acid is 12:5.5;

[0034] Step 2: Dissolve dopamine in deionized water, and then add tris(hydroxymethyl)aminomethane and tris(hydroxymethyl)aminomethane hydrochloride to obtain a dopamine buffer solution with pH = 8.5; immerse the non-woven fabric in the dopamine buffer solution for 12 h to obtain a superhydrophilic non-woven fabric; then immerse the superhydrophilic non-woven fabric in 3-mercaptopropylmethyldimethoxysilane and react at 92 °C for 60 min to obtain a modified superhydrophilic non-woven fabric; the mass-volume ratio of dopamine to deionized water is 0.005∶2;

[0035] Step 3: Dissolve chitosan and 5-chlorosalicylaldehyde in dimethyl sulfoxide, and then add 4A molecular sieve, and stir and react at 62 °C for 13 h. After the reaction, precipitate separation, washing, and freeze-drying are carried out to obtain Schiff base chitosan; then mix Schiff base chitosan, inhibitor methylhydroquinone, triethylamine, and tetrahydrofuran, stir and dissolve at 70 °C, and then dropwise add a tetrahydrofuran solution of acryloyl chloride, and continue to stir and react for 13 h. After the reaction, liquid separation, washing, filtration, rotary evaporation, and recrystallization are carried out to obtain acryloyl-modified chitosan antibacterial material; when preparing Schiff base chitosan, the reaction mass ratio of chitosan, 5-chlorosalicylaldehyde, and 4A molecular sieve is 3:1.8:0.7; when preparing acryloyl-modified chitosan antibacterial material, the reaction mass ratio of Schiff base chitosan to acryloyl chloride is 1:1.1;

[0036] Mix 350 g of acrylic acid and 470 g of deionized water, fully stir and then dropwise add 240 g of 49 wt% sodium hydroxide solution. After neutralization, add 3.5 g of trimethylolpropane triacrylate, 5 g of acryloyl-modified chitosan antibacterial material, 0.7 g of potassium persulfate, 0.4 g of sodium bisulfite, and 0.2 g of sodium dodecyl sulfate. After stirring evenly, heat up to 55 °C and react for 4 h. After the reaction, carry out colloid breaking, drying, and crushing and sieving to obtain a superabsorbent resin; then lay and form the superabsorbent resin to obtain an absorption layer; the process parameters for laying and forming: temperature is 30 °C, pressure is 0.4 MPa, and speed is 6 m / min;

[0037] Step 4: Cover the absorbent layer, modified superhydrophilic non-woven fabric, and hydrophilic non-woven fabric on the breathable SMS non-woven fabric in sequence, and hot-press and bond them with hot melt adhesive to obtain a highly breathable and moisture-permeable medical sheet; wherein the hot-press pressure is 2.5 kgf / m 2 ; The hot-press temperature is divided into two stages: the first stage is heating at 65°C for 1.5 h, and the second stage is heating at 120°C for 2.5 min.

[0038] Example 3: Step 1: Add tris(hydroxymethyl)aminomethane, 0.1 mol / L hydrochloric acid, and deionized water to obtain a buffer solution with pH = 8; then add tannic acid to the buffer solution to obtain a tannic acid solution; immerse the non-woven fabric in the tannic acid solution for 15 h, and after immersion, obtain a hydrophilic non-woven fabric; in the tannic acid solution, the reaction mass ratio of tris(hydroxymethyl)aminomethane to tannic acid is 12:5.5;

[0039] Step 2: Dissolve dopamine in deionized water, then add tris(hydroxymethyl)aminomethane and tris(hydroxymethyl)aminomethane hydrochloride to obtain a dopamine buffer solution with pH = 8.5; immerse the non-woven fabric in the dopamine buffer solution for 10 h to obtain a superhydrophilic non-woven fabric; then immerse the superhydrophilic non-woven fabric in 3-mercaptopropylmethyldimethoxysilane and react at 90°C for 50 min to obtain a modified superhydrophilic non-woven fabric; the mass-volume ratio of dopamine to deionized water is 0.005∶2;

[0040] Step 3: Dissolve chitosan and 5-chlorosalicylaldehyde in dimethyl sulfoxide, then add 4A molecular sieve, and stir and react at 60°C for 10 h. After the reaction, perform precipitation separation, washing, and freeze-drying to obtain Schiff-base chitosan; then mix Schiff-base chitosan, inhibitor methylhydroquinone, triethylamine, and tetrahydrofuran, stir to dissolve at 65°C, then dropwise add a tetrahydrofuran solution of acryloyl chloride, and continue to stir and react for 12 h. After the reaction, perform liquid separation, washing, filtration, rotary evaporation, and recrystallization to obtain acryloyl-modified chitosan antibacterial material; when preparing Schiff-base chitosan, the reaction mass ratio of chitosan, 5-chlorosalicylaldehyde, and 4A molecular sieve is 3∶1.8∶0.7; when preparing acryloyl-modified chitosan antibacterial material, the reaction mass ratio of Schiff-base chitosan to acryloyl chloride is 1:1.1;

[0041] Mix 350 g of acrylic acid and 470 g of deionized water, fully stir, then dropwise add 240 g of 48 wt% sodium hydroxide solution. After neutralization, add 3.5 g of trimethylolpropane triacrylate, 5 g of acryloyl-modified chitosan antibacterial material, 0.7 g of potassium persulfate, 0.4 g of sodium bisulfite, and 0.2 g of sodium dodecyl sulfate. Stir evenly and then heat up to 50°C and react for 3 h. After the reaction, perform colloid breaking, drying, and pulverizing and sieving to obtain a superabsorbent resin; then lay and form the superabsorbent resin to obtain an absorbent layer; the process parameters for laying and forming: temperature is 25°C, pressure is 0.3 MPa, and speed is 5 m / min;

[0042] Step 4: Cover the absorbent layer, modified superhydrophilic non-woven fabric, and hydrophilic non-woven fabric on the breathable SMS non-woven fabric in sequence, and hot-press and bond them with hot melt adhesive to obtain a highly breathable and moisture-permeable medical pad; wherein the hot-press pressure is 2 kgf / m 2 ; The hot-press temperature is divided into two stages: the first stage is heating at 60°C for 1 h, and the second stage is heating at 100°C for 2 min.

[0043] Comparative Example 1: Remove the propenyl-modified chitosan antibacterial material, and the rest is the same as in Example 1. The specific steps are as follows: Step 1: Add tris(hydroxymethyl)aminomethane, 0.1 mol / L hydrochloric acid, and deionized water to obtain a buffer solution with pH = 8; then add tannic acid to the buffer solution to obtain a tannic acid solution; immerse the non-woven fabric in the tannic acid solution for 20 h, and after immersion, obtain a hydrophilic non-woven fabric; in the tannic acid solution, the reaction mass ratio of tris(hydroxymethyl)aminomethane and tannic acid is 12:5.5;

[0044] Step 2: Dissolve dopamine in deionized water, and then add tris(hydroxymethyl)aminomethane and tris(hydroxymethyl)aminomethane hydrochloride to obtain a dopamine buffer solution with pH = 8.5; immerse the non-woven fabric in the dopamine buffer solution for 15 h to obtain a superhydrophilic non-woven fabric; then immerse the superhydrophilic non-woven fabric in 3-mercaptopropylmethyldimethoxysilane and react at 95°C for 70 min to obtain a modified superhydrophilic non-woven fabric; the mass-volume ratio of dopamine and deionized water is 0.005∶2;

[0045] Step 3: Mix 350 g of acrylic acid and 470 g of deionized water, stir well, then dropwise add 240 g of 50 wt% sodium hydroxide solution, after neutralization, add 3.5 g of trimethylolpropane triacrylate, 0.7 g of potassium persulfate, 0.4 g of sodium bisulfite, and 0.2 g of sodium dodecyl sulfate, stir evenly and heat up to 60°C for reaction for 5 h. After the reaction, carry out colloid breaking, drying, pulverizing and sieving to obtain a superabsorbent resin; then lay and mold the superabsorbent resin to obtain an absorbent layer; the process parameters for laying and molding: the temperature is 35°C, the pressure is 0.5 MPa, and the speed is 7 m / min;

[0046] Step 4: Cover the absorbent layer, modified superhydrophilic non-woven fabric, and hydrophilic non-woven fabric on the breathable SMS non-woven fabric in sequence, and hot-press and bond them with hot melt adhesive to obtain a highly breathable and moisture-permeable medical pad; wherein the hot-press pressure is 3 kgf / m 2 ; The hot-press temperature is divided into two stages: the first stage is heating at 70°C for 2 h, and the second stage is heating at 150°C for 3 min.

[0047] Comparative Example 2: Remove the modified superhydrophilic non-woven fabric, and the rest is the same as in Example 1. The specific steps are as follows: Step 1: Add tris(hydroxymethyl)aminomethane, 0.1 mol / L hydrochloric acid, and deionized water to obtain a buffer solution with pH = 8; then add tannic acid to the buffer solution to obtain a tannic acid solution; immerse the non-woven fabric in the tannic acid solution for 20 h, and after the immersion, obtain a hydrophilic non-woven fabric; in the tannic acid solution, the reaction mass ratio of tris(hydroxymethyl)aminomethane to tannic acid is 12:5.5;

[0048] Step 2: Dissolve chitosan and 5-chlorosalicylaldehyde in dimethyl sulfoxide, then add 4A molecular sieve, and stir and react at 65 °C for 15 h. After the reaction, perform precipitation separation, washing, and freeze-drying to obtain Schiff-base chitosan; then mix Schiff-base chitosan, inhibitor methylhydroquinone, triethylamine, and tetrahydrofuran, stir to dissolve at 75 °C, and then dropwise add a tetrahydrofuran solution of acryloyl chloride, and continue to stir and react for 14 h. After the reaction, perform liquid separation, washing, filtration, rotary evaporation, and recrystallization to obtain acryloyl-modified chitosan antibacterial material; when preparing Schiff-base chitosan, the reaction mass ratio of chitosan, 5-chlorosalicylaldehyde, and 4A molecular sieve is 3:1.8:0.7; when preparing acryloyl-modified chitosan antibacterial material, the reaction mass ratio of Schiff-base chitosan to acryloyl chloride is 1:1.1;

[0049] Mix 350 g of acrylic acid and 470 g of deionized water, fully stir, and then dropwise add 240 g of 50 wt% sodium hydroxide solution. After neutralization, add 3.5 g of trimethylolpropane triacrylate, 5 g of acryloyl-modified chitosan antibacterial material, 0.7 g of potassium persulfate, 0.4 g of sodium bisulfite, and 0.2 g of sodium dodecyl sulfate. Stir evenly and then heat up to 60 °C and react for 5 h. After the reaction, perform colloid breaking, drying, pulverizing, and sieving to obtain a superabsorbent resin; then lay and form the superabsorbent resin to obtain an absorbent layer; the process parameters for laying and forming: temperature is 35 °C, pressure is 0.5 MPa, and speed is 7 m / min;

[0050] Step 3: Cover the absorbent layer and the hydrophilic non-woven fabric on the breathable SMS non-woven fabric in sequence, and perform hot pressing and bonding with hot melt adhesive to obtain a highly breathable and moisture-permeable medical pad; wherein the hot pressing pressure is 3 kgf / m 2 ; The hot pressing temperature is divided into two stages: the first stage is heating at 70 °C for 2 h, and the second stage is heating at 150 °C for 3 min.

[0051] Comparative Example 3: Replace the modified superhydrophilic non-woven fabric and hydrophilic non-woven fabric with ordinary non-woven fabric, and the rest is the same as in Example 1. The specific steps are as follows: Step 1: Dissolve chitosan and 5-chlorosalicylaldehyde in dimethyl sulfoxide, then add 4A molecular sieve, and stir and react at 65 °C for 15 h. After the reaction, precipitate separation, washing, and freeze-drying are carried out to obtain Schiff base chitosan; then mix Schiff base chitosan, inhibitor methylhydroquinone, triethylamine, and tetrahydrofuran, stir to dissolve at 75 °C, and then dropwise add a tetrahydrofuran solution of acryloyl chloride, and continue to stir and react for 14 h. After the reaction, liquid separation, washing, filtration, rotary evaporation, and recrystallization are carried out to obtain acryloyl-modified chitosan antibacterial material; when preparing Schiff base chitosan, the reaction mass ratio of chitosan, 5-chlorosalicylaldehyde, and 4A molecular sieve is 3:1.8:0.7; when preparing acryloyl-modified chitosan antibacterial material, the reaction mass ratio of Schiff base chitosan and acryloyl chloride is 1:1.1;

[0052] Mix 350 g of acrylic acid and 470 g of deionized water, fully stir and then dropwise add 240 g of 50 wt% sodium hydroxide solution. After neutralization, add 3.5 g of trimethylolpropane triacrylate, 5 g of acryloyl-modified chitosan antibacterial material, 0.7 g of potassium persulfate, 0.4 g of sodium bisulfite, and 0.2 g of sodium dodecyl sulfate. After stirring evenly, heat up to 60 °C and react for 5 h. After the reaction, carry out colloid breaking, drying, and pulverizing and sieving to obtain superabsorbent resin; then lay and shape the superabsorbent resin to obtain an absorbent layer; Laying and shaping process parameters: temperature is 35 °C, pressure is 0.5 MPa, and speed is 7 m / min;

[0053] Step 2: Cover the absorbent layer and two layers of non-woven fabric on the breathable SMS non-woven fabric in sequence, and carry out hot melt adhesive hot pressing and bonding to obtain a highly breathable and moisture-permeable medical pad; where the hot pressing pressure is 3 kgf / m 2 ; The hot pressing temperature is divided into two stages: the first stage is heating at 70 °C for 2 h, and the second stage is heating at 150 °C for 3 min.

[0054] Detection test:

[0055] Antibacterial rate test: Use the finished pad prepared in the present invention as a specimen, and test the antibacterial rate of the specimen against Escherichia coli according to the GB 15979-2002 standard.

[0056] Absorption speed test: Use the finished pad prepared in the present invention as a specimen, put the specimen into a beaker containing 50 mL of deionized water and add a magnetic stirrer to stir. Start timing after putting in the specimen. When the vortex in the middle liquid level disappears after the specimen absorbs deionized water, and when the liquid level reaches horizontal when the vortex disappears, it is the end point, and measure the time required to reach the end point.

[0057] Water absorption rate test: Take the finished mattress pad prepared by the present invention as a specimen. After completely wetting the specimen and draining it, measure the mass of the specimen before and after wetting and substitute it into the formula to calculate the mass of liquid absorbed by the material per unit mass, expressed as a percentage.

[0058] Absorption uniformity: Take 50 mL of deionized water, add 3 drops of food coloring, and stir evenly to obtain a test solution that is easy to observe. Take the finished mattress pad prepared by the present invention as a specimen, lay the specimen flat on a flat experimental tabletop, use a dropper to suck 5 mL of the test solution and vertically drop it onto the center position of the specimen. Observe the diffusion of the test solution on the specimen 5 minutes after dropping. The results are as follows in the table:

[0059]

[0060] Conclusion: The dosages of Examples 1 to 3 remain unchanged, only some reaction parameters are modified. From the experimental data, it can be seen that there are no obvious fluctuations in the performance of the specimens.

[0061] Comparative Example 1: Remove the allyl-modified chitosan antibacterial material, and the rest is the same as in Example 1. From the experimental data, it can be seen that compared with Example 1, the antibacterial rate is 78.2%. The reason for the analysis is that the allyl-modified chitosan antibacterial material contains various antibacterial substances such as the Schiff base C=N structure and the chitosan antibacterial material. Therefore, it can effectively improve the antibacterial performance of the specimen. So after removing it, the antibacterial performance decreases and the antibacterial rate drops.

[0062] Comparative Example 2: Remove the modified superhydrophilic non-woven fabric, and the rest is the same as in Example 1. From the experimental data, it can be seen that compared with Example 1, the absorption rate is 8 s, the water absorption rate is 740%, and the color distribution on the surface of the mattress pad specimen is uneven, with local color concentration. The reason for the analysis is that the modified superhydrophilic non-woven fabric, as the superhydrophilic layer on the inner layer, has strong hydrophilicity, can absorb the liquid transferred from the hydrophilic layer at a faster speed, and promote the liquid to quickly diffuse around, enabling the absorption material inside the mattress pad to be more fully utilized, avoiding local accumulation of liquid, and improving the overall absorption capacity. So after removing the modified superhydrophilic non-woven fabric, the absorption rate becomes slower, the water absorption rate decreases, and there is a phenomenon of local accumulation.

[0063] Comparative Example 3: Replace the modified super-hydrophilic non-woven fabric and the hydrophilic non-woven fabric with ordinary non-woven fabric, and the rest is the same as in Example 1. It can be seen from the experimental data that, compared with Example 1, the absorption rate is 15 s, the water absorption rate is 680%, and the surface color of the pad sample is uneven, with the color concentrated in many areas. The reason for the analysis is as follows: In the design of the present invention, the hydrophilic non-woven fabric is used as the surface layer and the modified super-hydrophilic non-woven fabric is used as the inner layer, which can allow the liquid to quickly pass through the hydrophilic layer and enter the super-hydrophilic layer and spread, avoiding the local accumulation of the liquid and improving the overall absorption capacity. Therefore, after replacing the modified super-hydrophilic non-woven fabric and the hydrophilic non-woven fabric with ordinary non-woven fabric, the absorption rate becomes slower, the water absorption rate decreases, and there is a phenomenon of color concentration in many areas.

[0064] It should be noted that in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variant thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or further includes elements inherent to such process, method, article or device.

[0065] Finally, it should be noted that the above are only the preferred embodiments of the present invention and are not used to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A process for preparing a highly air-permeable and moisture-permeable medical pad, characterized in that: The following steps are involved: Step 1: adding tris(hydroxymethyl)aminomethane, 0.10-0.12 mol / L hydrochloric acid and deionized water to obtain a buffer solution with a pH value of 7.8-8.0; then adding tannic acid to the buffer solution to obtain a tannic acid solution; immersing the non-woven fabric in the tannic acid solution for 15-20 hours, and obtaining a hydrophilic non-woven fabric after the immersion is completed; Step 2: dissolving dopamine in deionized water, and then adding tris(hydroxymethyl)aminomethane and tris(hydroxymethyl)aminomethane hydrochloride) to obtain a dopamine buffer solution with a pH of 8.5-8.7; immersing the non-woven fabric in the dopamine buffer solution for 10-15 hours to obtain a super-hydrophilic non-woven fabric; then immersing the super-hydrophilic non-woven fabric in mercaptopropylmethyldimethoxysilane, reacting at 90-95° C. for 50-70 minutes to obtain a modified super-hydrophilic non-woven fabric; Step 3: Mix acrylic acid and deionized water, stir thoroughly, then drop 48-50wt% sodium hydroxide solution, neutralize, add trimethylolpropane triacrylate, propylene-modified chitosan antibacterial material, potassium persulfate, sodium bisulfite, sodium dodecyl sulfate, stir evenly, heat to 50-60°C and react for 3-5h, after the reaction, crush the colloid, dry, grind and sieve to obtain a super absorbent resin; then lay the super absorbent resin to obtain an absorption layer; Step 4: Cover the absorbent layer, modified super-hydrophilic non-woven fabric, and hydrophilic non-woven fabric on the anti-seepage layer in sequence, and bond them by hot-melt adhesive and hot-pressing to obtain a highly breathable and moisture-permeable medical pad.

2. The process for preparing a highly air-permeable and moisture-permeable medical pad according to claim 1, characterized in that: In step 1, in the tannic acid solution, the reaction mass ratio of tris(hydroxymethyl)aminomethane to tannic acid is 12:(5-6).

3. The process for preparing a highly air-permeable and moisture-permeable medical pad according to claim 1, characterized in that: In step 2, the mass volume ratio of dopamine and deionized water is (0.004-0.005):

2.

4. The process for preparing a highly air-permeable and moisture-permeable medical pad according to claim 1, characterized in that: In step three, the contents of each component of the super absorbent resin are: by mass, 350-400 parts of acrylic acid, 470-500 parts of deionized water, 240-270 parts of sodium hydroxide solution, 3.5-4.0 parts of trimethylolpropane triacrylate, 3-5 parts of propylene-modified chitosan antibacterial material, 0.7-1.0 parts of potassium persulfate, 0.4-0.6 parts of sodium bisulfite, and 0.2-0.3 parts of sodium dodecyl sulfate.

5. The process for preparing a highly air-permeable and moisture-permeable medical pad according to claim 4, characterized in that: The preparation process of the allyl-modified chitosan antibacterial material is as follows: chitosan and 5-chlorosalicylaldehyde are dissolved in dimethyl sulfoxide, and then 4A molecular sieves are added, and the reaction is stirred at 60-65°C for 10-15 hours. After the reaction is completed, the Schiff-alkalized chitosan is obtained by precipitation separation, washing, and freeze-drying; then the Schiff-alkalized chitosan, inhibitor methylhydroquinone, triethylamine and tetrahydrofuran are mixed, stirred at 65-75°C until dissolved, and then a tetrahydrofuran solution of acryloyl chloride is added dropwise, and the stirring reaction is continued for 12-14 hours. After the reaction is completed, the allyl-modified chitosan antibacterial material is obtained by separation, washing, filtration, rotary evaporation, and recrystallization.

6. The process for preparing a highly air-permeable and moisture-permeable medical pad according to claim 5, characterized in that: When preparing Schiff alkalinized chitosan, the reaction mass ratio of chitosan, 5-chlorosalicylaldehyde and 4A molecular sieve is 3:(1.7-2.0):0.

7.

7. The process for preparing a highly air-permeable and moisture-permeable medical pad according to claim 5, characterized in that: When preparing the propylene-modified chitosan antibacterial material, the reaction mass ratio of Schiff-alkalized chitosan and acryloyl chloride is 1:(1.0-1.2).

8. The process for preparing a highly air-permeable and moisture-permeable medical pad according to claim 1, characterized in that: In step three, the laying molding process parameters are: temperature is 25-35°C, pressure is 0.3-0.5MPa, and speed is 5-7m / min.

9. The process for preparing a highly air-permeable and moisture-permeable medical pad according to claim 1, characterized in that: In step 4, the hot pressing pressure is 2-3kgf / m 2 The hot pressing temperature is divided into two stages: the first stage is heating at 60-70°C for 1-2h, and the second stage is heating at 100-150°C for 2-3min; the anti-seepage layer is a breathable SMS non-woven fabric.

10. A highly breathable and moisture permeable medical pad, characterized in that: Prepared according to the preparation process according to any one of claims 1 to 9.

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