Production method of water-soluble chitosan fiber non-woven fabric

Abstract

The invention relates to a production method of a water-soluble chitosan fiber non-woven fabric. The production method comprises the following steps: 1) preparing raw materials; 2) preparing fibers; 3) cotton blending; 4) carding; (5) lapping; (6) needling; (7) lustring; and 8) coiling. Water-soluble chitosan is adopted to be made into the non-woven fabric, chitosan fibers can be degraded by most of microorganisms and cannot pollute the environment, the chitosan fibers can adsorb and inhibit growth of bacteria through ion exchange, electrostatic adsorption and other modes, and the chitosan fibers have temperature sensing performance and can be changed according to the environment temperature and humidity. The material can automatically adjust the body surface temperature and keep comfort, can be used in burn wounds and donor areas, not only plays a role in covering and protecting the wounds, but also is decomposed under the action of enzyme in organisms, can be absorbed by the organisms, and has affinity with the organisms, so that the material is low in antigenicity, large in adsorption capacity of blood components such as serum protein and the like, and can be used for treating the burn wounds and the donor areas. The capability of promoting wound healing is realized.

Description

Technical Field

[0001] The present invention relates to the technical field of non-woven fabrics, and specifically to a production method of a water-soluble chitosan fiber non-woven fabric. Background Art

[0002] Non-woven fabrics, also known as non-woven materials, non-woven cloths, or non-woven fabrics, are made by orienting or randomly arranging fibers through friction, entanglement, adhesion, or a combination of these methods, with the essence being "non-woven". Non-woven fabrics exist in the form of fibers in the cloth. The main fiber raw materials for non-woven fabrics are polypropylene fibers (polypropylene), polyester fibers (polyester), polyamide fibers, polyacrylonitrile fibers, viscose fibers, etc., all of which can be used to produce non-woven fabrics.

[0003] For example, a production method of a spunlace non-woven fabric blended with PLA and bamboo fibers proposed in 202410092321.2 has excellent biodegradability, antibacterial, odor-proof, breathable, moisture-absorbing and moisture-wicking, and wear-resistant properties. At the same time, its water absorption and penetration are relatively slower than that of degreased products, and it is suitable for product fields such as high-end customized handbags and the outer layer of wound dressings. However, when applied to the medical field, the water-soluble non-woven fabrics in the prior art have poor temperature sensitivity, cannot adapt to changes in environmental temperature and humidity, resulting in a decrease in comfort, and their antibacterial properties are average, and it is easy to have bacterial growth, affecting patients. Therefore, a production method of a water-soluble chitosan fiber non-woven fabric is proposed to prepare a new type of water-soluble non-woven fabric to solve the above problems. Summary of the Invention

[0004] Aiming at the deficiencies of the prior art, the present invention provides a production method of a water-soluble chitosan fiber non-woven fabric, which has the advantages of good biodegradability, strong antibacterial property, and temperature sensitivity, and solves the problems that the water-soluble non-woven fabrics in the prior art have poor temperature sensitivity when applied to the medical field, cannot adapt to changes in environmental temperature and humidity, resulting in a decrease in comfort, and their antibacterial properties are average, and it is easy to have bacterial growth, affecting patients.

[0005] To achieve the above object, the present invention provides the following technical solution: A production method of a water-soluble chitosan fiber non-woven fabric, comprising the following steps:

[0006] 1) Raw material preparation

[0007] Take chitosan with a deacetylation degree of 75 - 85% and an average molecular weight of 2.0×10 5 - 3.5×10 5 , add organic solvents dimethyl sulfoxide and dimethylacetamide, and obtain spinning dope A with a concentration of 12 - 25% after filtration and degassing, and remove impurities by pressure filtration;

[0008] 2) Fiber preparation

[0009] Feed the above spinning dope A into a wet spinning machine to form chitosan fibers;

[0010] 3) Blending

[0011] Mix the chitosan fibers obtained in 2) in a cotton blender and then feed them into a cotton bin;

[0012] 4) Carding

[0013] Use a carding machine to card the blended chitosan fibers into a single fiber state to form a web-like fiber thin layer;

[0014] 5) Web laying

[0015] Use a web laying machine to evenly lay the width and number of layers of the above web-like fiber thin layer;

[0016] 6) Needle punching

[0017] Use a needle punching machine to needle punch the web-like fiber thin layer in 5). This process is set with two needle punchings to obtain chitosan fiber non-woven fabric;

[0018] 7) Calendering

[0019] Feed the chitosan fiber non-woven fabric in step 6) into a calendering machine and perform calendering operation on its surface at 130 °C;

[0020] 8) Rewinding

[0021] The chitosan fiber non-woven fabric after calendering is wound into a roll by a winding machine.

[0022] Preferably, the deacetylation step of the chitosan in 1) is as follows:

[0023] Dissolve chitosan in 60 mL of 2% acetic acid solution, dilute it with 60 mL of methanol, then add 2 mL of acetic anhydride, stir evenly and let it stand overnight. The next day, drop the reaction mixture into 500 mL of 0.5 mol / L KOH-ethanol solution, filter out the white fibrous precipitate, wash it with ethanol until neutral, then dehydrate it with ether, and complete deacetylation after drying in vacuum at 70 °C.

[0024] Preferably, the process of the wet spinning machine in 2) is: the spinning dope A passes through a spinning metering pump, enters a candle filter, and after filtration, enters a spinneret through a connecting pipe. The thin stream of the spinning dope A is pressed into a coagulation bath, and the dope solidifies and precipitates to form chitosan fibers.

[0025] Preferably, the processing process of the cotton blender in 3) is as follows:

[0026] 1) Mixing

[0027] Put the pretreated raw materials into an automatic cotton blender for mixing;

[0028] 2) Drawing

[0029] The mixed fibers need to be stretched.

[0030] 4. Spinning

[0031] The stretched fibers can be spun into yarn.

[0032] Preferably, the needling process in 6) is as follows: The barbs on the needling machine drive the fibers on the surface and subsurface of the reticular fiber thin layer to move from the planar direction of the reticular fiber thin layer to the vertical direction of the reticular fiber thin layer, causing the fibers to shift up and down. The fibers that shift up and down exert a certain extrusion on the reticular fiber thin layer, causing the fibers in the reticular fiber thin layer to approach and compress.

[0033] Preferably, the process of the calendering machine in 7) is as follows: The heat energy generated by the combustion of fuel in the combustion chamber is transferred to the calendering roller in the calendering chamber through the heating chamber, raising the surface temperature of the calendering roller to the temperature for calendering textiles. The motor drives the calendering roller to rotate through the reduction gearbox, and the high-temperature calendering roller contacts the textile to instantaneously calender it.

[0034] Preferably, if there are impurities in the prepared chitosan fibers in 2), a bleaching operation is required. The specific process is as follows: Put the chitosan fibers into a boiling and bleaching machine, first add the pretreatment agent at room temperature, then heat up at a heating rate of 1.6 - 2.5 °C / min to 67 - 75 °C, and add hydrogen peroxide and keep it warm for 15 - 25 min; then heat up at a heating rate of 1.8 - 2.2 °C / min to 98 - 105 SSD, and keep it warm for 55 - 65 min; then, cool down to 62 - 68 °C and drain the water, then keep it warm at 65 - 75 °C for 15 - 20 min, and then cool down to 62 - 68 °C and drain the water; finally, add water and citric acid to the boiling and bleaching machine to carry out a neutralization and water washing treatment on the bleached non-woven fabric roll.

[0035] Preferably, during the winding process in 8), the surface defects of the fabric are detected, the fabric surface defects are repaired and removed, and then it is stored in a ventilated and dry place.

[0036] Compared with the prior art, the technical solution of this application has the following beneficial effects:

[0037] 1. The present invention uses water-soluble chitosan to make non-woven fabrics. Chitosan fibers can be degraded by most microorganisms. Different from traditional plastics, they do not cause environmental pollution. Chitosan fibers can adsorb and inhibit the growth of bacteria through ion exchange and electrostatic adsorption, etc., and thus have antibacterial properties. Chitosan fibers have temperature-sensitive properties and can automatically adjust the body surface temperature according to changes in environmental temperature and humidity to maintain a sense of comfort.

[0038] 2. The non-woven fabric prepared from chitosan in the present invention can be used on burn wounds and skin donor sites. It not only plays a role in covering and protecting the wound surface, but also decomposes in vivo through the action of enzymes, can be absorbed by the body, has an affinity with the organism, thus has low antigenicity, a large adsorption capacity for blood components such as serum proteins, and has the ability to promote wound healing. Detailed implementation mode

[0039] The following will combine the embodiments of the present invention to clearly and completely describe the technical solutions in 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. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts belong to the scope of protection of the present invention.

[0040] Embodiment

[0041] A production method of a water-soluble chitosan fiber non-woven fabric in this embodiment includes the following steps:

[0042] 1) Raw material preparation

[0043] Dissolve chitosan in 60 mL of 2% acetic acid solution, dilute with 60 mL of methanol, add 2 mL of acetic anhydride, stir evenly and let stand overnight. The next day, drop the reaction mixture into 500 mL of 0.5 mol / L KOH-ethanol solution, filter out the white fibrous precipitate, wash with ethanol until neutral, then dehydrate with ether, and dry in vacuum at 70 °C to obtain chitosan with a deacetylation degree of 75-85% and an average molecular weight of 2.0×10 5 -3.5×10 5 Add organic solvents dimethyl sulfoxide and dimethylacetamide, and after filtration and degassing, obtain spinning dope A with a concentration of 12-25%, and remove impurities by pressure filtration;

[0044] 2) Fiber preparation

[0045] Feed the above-mentioned spinning dope A into a wet spinning machine. The spinning dope A passes through a spinning metering pump, enters a candle filter, and after filtration, enters a spinneret through a connecting pipe. The thin stream of the spinning dope A is pressed into a coagulation bath, and the dope solidifies and precipitates to form chitosan fibers. If there are impurities in the prepared chitosan fibers, bleaching is required. Put the chitosan fibers into a boiling and bleaching machine, first add a pretreatment agent at room temperature, then heat and raise the temperature at a rate of 1.6 - 2.5 °C / min to 67 - 75 °C, and add hydrogen peroxide and keep it warm for 15 - 25 min; then heat and raise the temperature at a rate of 1.8 - 2.2 °C / min to 98 - 105 SSD, and keep it warm for 55 - 65 min; then, cool down to 62 - 68 °C to drain water, and then keep it warm at 65 - 75 °C for 15 - 20 min, and then cool down to 62 - 68 °C to drain water; finally, add water and citric acid to the boiling and bleaching machine to carry out neutralization and water washing treatment on the bleached non-woven fabric roll;

[0046] 3) Blending cotton

[0047] Mix the chitosan fibers obtained in 2) through a cotton blending machine and then feed them into a cotton box;

[0048] 4) Carding

[0049] Use a carding machine to card the blended chitosan fibers into a single fiber state to form a net-like fiber thin layer;

[0050] 5) Web laying

[0051] Use a web laying machine to evenly lay the width and number of layers of the above-mentioned net-like fiber thin layer;

[0052] 6) Needle punching

[0053] Use a needle punching machine to needle punch the net-like fiber thin layer in 5). The barbs on the needle punching machine drive the fibers on the surface and subsurface of the net-like fiber thin layer to move from the plane direction of the net-like fiber thin layer to the vertical direction of the net-like fiber thin layer, causing the fibers to shift up and down. The fibers that shift up and down exert a certain extrusion on the net-like fiber thin layer, causing the fibers in the net-like fiber thin layer to approach and compress. This process is set with two needle punchings to obtain chitosan fiber non-woven fabric;

[0054] 7) Calendering

[0055] Feed the chitosan fiber non-woven fabric in step 6) into a calendering machine. The heat energy generated by the combustion of fuel in the combustion chamber is transferred to the calendering roll in the calendering chamber, causing the surface temperature of the calendering roll to rise to reach the temperature for calendering textiles. The motor drives the calendering roll to rotate through a speed reducer, and the 130 °C high-temperature calendering roll contacts the textile to instantaneously calender it;

[0056] 8) Rewinding

[0057] The chitosan fiber non-woven fabric after calendering and glazing is wound into a roll by a coiler, and the surface defects of the fabric are detected, repaired and removed, and then stored in a ventilated and dry place.

[0058] Experimental Example

[0059] 1) Skin sensitization test

[0060] The extract of the water-soluble chitosan fiber non-woven fabric was injected into the back of rabbits in the experimental group, and physiological saline was used as a control injection. The conditions of the injection sites were observed at 24, 48, and 72 hours. The test results are shown in the following table:

[0061]

[0062] Then, the extract of the water-soluble chitosan fiber non-woven fabric, physiological saline, and 5% formaldehyde were respectively injected on both sides of the backs of 12 guinea pigs. The conditions of the injection sites were observed at 1, 24, and 48 hours. The results are as follows:

[0063]

[0064] In the table, A, B, C, D represent the erythema and edema grades, and the numbers represent the number of guinea pigs.

[0065] The results show that the water-soluble chitosan fiber non-woven fabric has no sensitization reaction to the skin.

[0066] 2) Skin irritation test

[0067] The sterile water-soluble chitosan fiber non-woven fabric with a specification of 2.5 cm × 3 cm was applied to both sides of the backs of rabbits. The negative control was to wet the non-woven fabric with physiological saline, and the positive control was to wet the non-woven fabric with 5% formaldehyde solution.

[0068]

[0069]

[0070] In the table, ER represents the erythema reaction, ED represents the edema reaction, P1 represents the irritation index, and AP1 represents the average irritation index. The test results show that the water-soluble chitosan fiber non-woven fabric has no irritation.

[0071] It should be noted that in this text, 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 "comprising", "including" or any other variant thereof are intended to cover non-exclusive inclusion, such that a process, method, article or device comprising 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. Without further limitation, an element defined by the statement "comprising an..." does not exclude the presence of additional identical elements in the process, method, article or device comprising said element.

[0072] Although embodiments of the present invention have been shown and described, it will be understood by those of ordinary skill in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A production method of a water-soluble chitosan fiber non-woven fabric, characterized in that, It includes the following steps: 1) Raw material preparation Chitosan with a degree of deacetylation of 75 - 85% and an average molecular weight of 2.0×10 5 - 3.5×10 5 is taken, organic solvents dimethyl sulfoxide and dimethylacetamide are added, and after filtration and degassing, spinning dope A with a concentration of 12 - 25% is obtained, and impurities are removed by pressure filtration; 2) Fiber preparation Feed the above-mentioned spinning dope A into a wet spinning machine to form chitosan fibers; 3) Blending cotton After the chitosan fibers obtained in 2) are mixed by a cotton blending machine, they are fed into a cotton box; 4) Carding Use a carding machine to card the blended chitosan fibers into a single fiber state to form a net-like fiber thin layer; 5) Web laying Use a web laying machine to evenly lay the width and number of layers of the above-mentioned net-like fiber thin layer; 6) Needling Use a needling machine to needle the net-like fiber thin layer in 5). Two needling operations are set in this process to obtain chitosan fiber non-woven fabric; 7) Calendering Feed the chitosan fiber non-woven fabric in step 6) into a calendering machine and perform calendering operation on its surface at 130 °C; 8) Coiling The calendered chitosan fiber non-woven fabric is coiled by a coiling machine.

2. The production method of a water-soluble chitosan fiber non-woven fabric according to claim 1, characterized in that, The deacetylation step of chitosan in 1) is as follows: Dissolve chitosan in 60 mL of 2% acetic acid solution, dilute it with 60 mL of methanol, add 2 mL of acetic anhydride, stir evenly and let it stand overnight. The next day, drop the reaction mixture into 500 mL of 0.5 mol / L KOH-ethanol solution, filter out the white fibrous precipitate, wash it with ethanol until neutral, then dehydrate it with ether, and complete deacetylation after vacuum drying at 70 °C.

3. The production method of a water-soluble chitosan fiber non-woven fabric according to claim 1, characterized in that, The process of the wet spinning machine in 2) is: The spinning dope A passes through a spinning metering pump, enters a candle-shaped filter, and after filtration, enters a spinneret through a connecting pipe. The fine stream of the spinning dope A is pressed into a coagulation bath, and the dope solidifies and precipitates to form chitosan fibers.

4. The production method of a water-soluble chitosan fiber non-woven fabric according to claim 1, characterized in that, The processing process of the cotton blending machine in 3) is as follows: 1) Mixing Put the pretreated raw materials into an automatic cotton blending machine for mixing; 2) Drawing The mixed fibers need to be drawn; 4. Spinning The drawn fibers can be spun to process the fibers into threads.

5. The production method of a water-soluble chitosan fiber non-woven fabric according to claim 1, characterized in that, The needling process in 6) is: The barbs on the needling machine drive the fibers on the surface and subsurface of the net-like fiber thin layer to move from the plane direction of the net-like fiber thin layer to the vertical direction of the net-like fiber thin layer, causing the fibers to shift up and down. The fibers that shift up and down exert a certain pressure on the net-like fiber thin layer, causing the fibers in the net-like fiber thin layer to approach and compress.

6. The production method of a water-soluble chitosan fiber non-woven fabric according to claim 1, characterized in that, The process of the calendering machine in 7) is: The heat energy generated by the combustion of fuel in the combustion chamber is transferred to the calendering roller in the calendering chamber through the heating chamber, causing the surface temperature of the calendering roller to rise to the temperature for calendering textiles. The motor drives the calendering roller to rotate through a reduction gearbox, and the high-temperature calendering roller contacts the textile to instantaneously calender it.

7. The production method of a water-soluble chitosan fiber non-woven fabric according to claim 1, characterized in that, If there are impurities in the prepared chitosan fibers in the above (2), bleaching operations need to be carried out. The specific process is as follows: Put the chitosan fibers into a boiling and bleaching machine, first input the pretreatment agent at room temperature, then heat up at a heating rate of 1.6 - 2.5 °C / min to 67 - 75 °C, and input hydrogen peroxide and keep it warm for 15 - 25 minutes; then heat up at a heating rate of 1.8 - 2.2 °C / min to 98 - 105 SSD, and keep it warm for 55 - 65 minutes; then, cool down to 62 - 68 °C and drain the water, then keep it warm at 65 - 75 °C for 15 - 20 minutes, and then cool down to 62 - 68 °C and drain the water; finally, add water and citric acid to the boiling and bleaching machine to carry out neutralization and water washing treatment on the bleached non-woven fabric roll.

8. The production method of a water-soluble chitosan fiber non-woven fabric according to claim 1, characterized in that, During the winding process in the above (8), detect the defects on the fabric surface, repair and remove the defects on the fabric surface, and then store it in a ventilated and dry place.

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