Preparation method of plant fiber non-woven fabric

Abstract

The invention relates to a preparation method of a plant fiber non-woven fabric, the plant fiber non-woven fabric comprises Brazil eucalyptus wood, cotton, flax, bamboo and the like, fibers of the Brazil eucalyptus wood, the cotton, the flax, the bamboo and the like can be made into the non-woven fabric through a non-woven technology, the plant fiber is a thick-wall tissue widely distributed in seed plants, cells of the plant fiber are thin and long, two ends of the plant fiber are sharp, and the plant fiber is a plant fiber. Brazil eucalyptus wood has a thick secondary wall, single-line holes are often formed in the wall, in the method, black liquor generated by the Brazil eucalyptus wood raw material contains a large number of suspended solids, organic pollutants and toxic substances, and serious pollution can be caused when the black liquor is directly discharged into a water body. In order to solve the problem that papermaking black liquor can be prepared into lignosulfonate by precipitating, separating and drying precipitators such as lime, calcium chloride and basic lead acetate, the polymerization time of the previous two organic solvents is generally more than 10 hours, but the concentration of a spinning solution with strong dissolving power is higher, the spinning speed can be properly improved, the solvent recovery is simpler and more convenient, and the lignosulfonate can be prepared into lignosulfonate. And the obtained fiber has good performance.

Description

Technical Field

[0001] The invention relates to the technical field of plant fiber nonwoven fabrics, in particular to a method for preparing plant fiber nonwoven fabrics. Background Art

[0002] Plant fiber non-woven fabrics are not made of yarns interwoven and knitted together, but the fibers are directly bonded together by physical methods. Therefore, when you take the sticky scales in your clothes, you will find that you cannot pull out the threads one by one. Non-woven fabrics break through the traditional textile principles and have the characteristics of short process flow, fast production rate, high output, low cost, wide application, and multiple sources of raw materials.

[0003] In the prior art, the invention with patent number CN113279143B discloses a degradable flame-retardant plant fiber non-woven fabric, which belongs to the technical field of non-woven fabrics. It includes a plant fiber non-woven fabric with polylactic acid as the main body and a flame retardant slurry impregnated on the surface of the base fabric, and uses the ion state produced by chitosan dissolved in malic acid as the medium to anchor the Zn-MOF-74 / PVA flame retardant on the surface of the plant fiber non-woven fabric base fabric, thereby producing a flame retardant effect; the hydrophilicity produced by the synergistic effect of the rich hydroxyl structure on the surface of the flame retardant, the polar groups such as hydroxyl and amino groups contained in chitosan, and the cotton stalk fiber doped in the non-woven fabric is used to optimize and complement the hydrophobicity of polylactic acid, and effectively increase its hydrolysis degradation rate; at the same time, the doping of polyamide fiber and flax fiber improves the wear resistance, antibacterial, antistatic and other properties of the non-woven fabric, and expands the application range of the non-woven fabric.

[0004] The hydrophilicity of the existing plant fiber non-woven fabrics produced by the synergy of cotton stalk fibers makes it easy to stick to the wearer's skin. The degradation rate is too fast, which affects the service life of the plant fiber non-woven fabrics. The ionic state produced by chitosan dissolved in malic acid is used as a medium, which reduces the quality of the non-woven fabric. For this reason, we propose a method for preparing plant fiber non-woven fabrics. Summary of the invention

[0005] The purpose of the present invention is to provide a method for preparing a plant fiber nonwoven fabric.

[0006] To achieve the above purpose, the present invention provides the following technical solutions: a method for preparing plant fiber non-woven fabrics, the plant fiber non-woven fabrics include: Brazilian eucalyptus, cotton, flax, bamboo, etc., their fibers can be made into non-woven fabrics through non-woven technology, plant fiber is a thick wall tissue widely distributed in seed plants, its cells are slender, sharp at both ends, with thick secondary walls, often with single pits on the wall, and generally no living protoplasts when mature. Plant fiber is a filamentous or flocculent substance generated by the combination of cellulose and various nutrients, which has the functions of supporting, connecting, wrapping, filling, etc. for plants, and is widely present in plant stems, roots, fruits, and fruit shells;

[0007] The specific preparation method comprises the following steps:

[0008] Step 1, fully drying the polylactic acid in a vacuum drying oven at 60° C., mixing it with cotton stalk fiber, flax fiber and polyamide fiber through a high-speed mixer to obtain a plant fiber mixture; melting the plant fiber mixture through screw extrusion, controlling the working temperature at 90° C. and the rotation speed at 55 r / min; and then spraying it through a spinneret hole to form polylactic acid fiber;

[0009] Step 2, Brazilian eucalyptus wood is mainly divided into softwood pulp and hardwood pulp. The softwood pulp fiber is long and thin, generally about 2.56-4.08mm in length, 40.9-50.4μm in width, and its aspect ratio is generally below 70. The softwood pulp fiber is relatively pure, with less impurities and a low pentose content of about 9%-12%. The fiber is not easy to absorb water and swell, has a high beating degree, and is not easy to break; the hardwood pulp fiber is thick and short;

[0010] Step 3. Brazilian eucalyptus wood fiber has a unique style that is significantly different from cotton, wood fiber fabrics and plain fiber fabrics. It has excellent wear resistance, no pilling, high moisture absorption, quick drying, high air permeability, and drape. It feels smooth and plump, as soft as silk. It is mildew-proof, moth-proof and antibacterial, cool and comfortable to wear, and has the effect of beauty and skin care. It has excellent dyeing performance, bright luster, and has good natural antibacterial effect and environmental protection.

[0011] Step 5: In the process of chemical pulping of Brazilian eucalyptus wood fiber, the principle is to retain cellulose and part of hemicellulose to the greatest extent, and lignin is the part that is removed as much as possible. When extracting cellulose and hemicellulose, the molecular structure of lignin has been basically destroyed and discharged together with the wastewater generated by the pulping process;

[0012] Step 6: Roll the synthetic fiber or natural fiber into a web shape, and then generate friction and static electricity between the fibers by stretching, impacting or compressing to form a fiber web, and finally strengthen it by heat pressing or post-treatment;

[0013] Step 7. Wood has inherent conductivity and transmission properties. The cross-section of wood fiber is highly hollow and covered with irregular pores of various sizes. It can absorb and evaporate a large amount of water in an instant. Its water absorption is three times that of cotton.

[0014] Step 8: Sheets, webs or pads made of fibers arranged in a directional or random manner, bonded together by friction, cohesion or bonding, or a combination of these methods. The fibers are bonded together by mechanical, chemical, thermal or other methods without spinning or weaving, forming a cloth-like or fiber-structured material;

[0015] Step 9: Feed, mix and open fiber raw materials of different properties, varieties or batches separately, or feed, mix and open together, so that the compressed fiber blocks in the fiber package are loosened into small fiber bundles through mechanical impact and tearing; further mix the fibers that have been initially opened so that different fibers can be fully mixed; further open the mixed fibers to form a mixed fiber layer for combing by a carding machine.

[0016] Preferably, the cellulose and various nutrients grow into single-cell fibers through seed epidermal cells, such as cotton and kapok, bast fiber: single fiber or technical fiber obtained from the phloem of some plants, such as flax, ramie, jute, bamboo fiber, leaf fiber: technical fiber obtained from the leaves or sheaths of some plants, such as sisal and abaca, fruit fiber: fiber obtained from the fruits of some plants, such as coconut fiber.

[0017] Preferably, in step 2, the general length is about 0.8-1.08 mm, the aspect ratio is within 60, and it contains more impurities. The finished product has relatively low strength, is relatively loose, has high bulk, and has a high pentose content, generally 21%-24%. It has strong absorption performance and is easy to crush into pulp. Therefore, the thickness and density of products produced by different wood pulps will be different.

[0018] Preferably, in step 8, compressed air is used as a medium for conveying fibers and a means of control. The specific process is as follows: fibers are conveyed to the upper cotton storage box through the cotton inlet under the action of airflow, and the airflow is led out from the exhaust pipe from the airflow outlets on both sides of the upper cotton storage box, and the fibers fall into the upper cotton storage box. If the height of the upper cotton storage box storing fibers remains unchanged, the pressure remains unchanged; if there are too many fibers, the airflow outlet will be covered more, the air discharge pressure will increase, and the pressure of the upper cotton storage box will increase. After the pressure increase signal is fed back, it will control the upper device to reduce the fiber feeding amount.

[0019] Preferably, in step 5, the black liquor produced contains a large amount of suspended solids, organic pollutants and toxic substances, which will cause serious pollution if directly discharged into the water body. In order to solve the papermaking black liquor, precipitants such as lime, calcium chloride, basic lead acetate, etc. are used to prepare lignin sulfonate through precipitation, separation, drying and other processes.

[0020] Preferably, in step 6, the solvent used for solution polymerization can dissolve both monomers and polymers, and the obtained polymerization solution is directly used for spinning. The solvents used for solution polymerization include dimethylformamide, dimethyl sulfoxide, sodium thiocyanate and zinc chloride, etc. The polymerization time using the first two organic solvents is generally more than 10 hours, but the concentration of the spinning solution is higher due to its strong dissolving power, the spinning speed can be appropriately increased, the solvent recovery is also relatively simple, and the obtained fiber has better performance.

[0021] Preferably, in step 7, the function of wood fiber textiles to keep warm in winter and cool in summer is unmatched by other fibers. It is cool and breathable in summer and autumn, and warm and comfortable in winter and spring, and can help eliminate excess heat and moisture in the body, so that people do not get irritated or dry.

[0022] In the present invention, Brazilian eucalyptus wood raw materials are mixed with plant stems, roots, fruits and fruit shells. The solvent used in solution polymerization can dissolve both monomers and polymers. The obtained polymerization solution is directly used for spinning. The solvent used in solution polymerization includes dimethylformamide, dimethyl sulfoxide, sodium thiocyanate and zinc chloride. Polylactic acid is fully dried in a vacuum drying oven at 60°C, and mixed with cotton stalk fibers, flax fibers and polyamide fibers through a high-speed mixer to obtain a plant fiber mixture. The plant fiber mixture is melted by screw extrusion, and the working temperature is controlled at 90°C and the rotation speed is controlled at 55r / min. Then, the plant fiber mixture is sprayed through a spinneret hole to form polylactic acid fibers, so as to reduce the hydrophilicity of the plant fiber non-woven fabric produced by the synergy of the cotton stalk fibers and the three, avoid being attached to the wearer's skin, and is not easy to be washed, degraded and damaged, thereby extending the service life of the plant fiber non-woven fabric. At the same time, the ion state produced by chitosan dissolved in malic acid is used as a medium to improve the quality of the non-woven fabric.

[0023] The black liquor produced by Brazilian eucalyptus wood raw materials contains a large amount of suspended solids, organic pollutants and toxic substances, which will cause serious pollution if discharged directly into the water body. In order to solve the black liquor of papermaking, lime, calcium chloride, basic lead acetate and other precipitants are used, and lignin sulfonate can be made through precipitation, separation, drying and other processes. The polymerization time of the first two organic solvents is generally more than 10 hours, but the concentration of the spinning solution is higher due to its strong solubility, which can appropriately increase the spinning speed, and the solvent recovery is also simple, and the obtained fiber has better performance. DETAILED DESCRIPTION

[0024] The technical solutions in the embodiments of the present invention are described clearly and completely. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0025] The present invention provides a technical solution: a method for preparing a plant fiber non-woven fabric, the plant fiber non-woven fabric includes: Brazilian eucalyptus, cotton, flax, bamboo, etc., their fibers can be made into non-woven fabrics through non-woven technology, plant fiber is a thick-walled tissue widely distributed in seed plants, its cells are slender, sharp at both ends, with thick secondary walls, often with single pits on the wall, and generally no living protoplasts when mature. Plant fiber is a filamentous or flocculent substance generated by the combination of cellulose and various nutrients, which has the functions of supporting, connecting, wrapping, filling, etc. for plants, and is widely present in plant stems, roots, fruits, and fruit shells;

[0026] The specific preparation method comprises the following steps:

[0027] Step 1, fully drying the polylactic acid in a vacuum drying oven at 60° C., mixing it with cotton stalk fiber, flax fiber and polyamide fiber through a high-speed mixer to obtain a plant fiber mixture; melting the plant fiber mixture through screw extrusion, controlling the working temperature at 90° C. and the rotation speed at 55 r / min; and then spraying it through a spinneret hole to form polylactic acid fiber;

[0028] Step 2, Brazilian eucalyptus wood is mainly divided into softwood pulp and hardwood pulp. The softwood pulp fiber is long and thin, generally about 2.56-4.08mm in length, 40.9-50.4μm in width, and its aspect ratio is generally below 70. The softwood pulp fiber is relatively pure, with less impurities and a low pentose content of about 9%-12%. The fiber is not easy to absorb water and swell, has a high beating degree, and is not easy to break; the hardwood pulp fiber is thick and short;

[0029] Step 3. Brazilian eucalyptus wood fiber has a unique style that is significantly different from cotton, wood fiber fabrics and plain fiber fabrics. It has excellent wear resistance, no pilling, high moisture absorption, quick drying, high air permeability, and drape. It feels smooth and plump, as soft as silk. It is mildew-proof, moth-proof and antibacterial, cool and comfortable to wear, and has the effect of beauty and skin care. It has excellent dyeing performance, bright luster, and has good natural antibacterial effect and environmental protection.

[0030] Step 5: In the process of chemical pulping of Brazilian eucalyptus wood fiber, the principle is to retain cellulose and part of hemicellulose to the greatest extent, and lignin is the part that is removed as much as possible. When extracting cellulose and hemicellulose, the molecular structure of lignin has been basically destroyed and discharged together with the wastewater generated by the pulping process;

[0031] Step 6: Roll the synthetic fiber or natural fiber into a web shape, and then generate friction and static electricity between the fibers by stretching, impacting or compressing to form a fiber web, and finally strengthen it by heat pressing or post-treatment;

[0032] Step 7. Wood has inherent conductivity and transmission properties. The cross-section of wood fiber is highly hollow and covered with irregular pores of various sizes. It can absorb and evaporate a large amount of water in an instant. Its water absorption is three times that of cotton.

[0033] Step 8: Sheets, webs or pads made of fibers arranged in a directional or random manner, bonded together by friction, cohesion or bonding, or a combination of these methods. The fibers are bonded together by mechanical, chemical, thermal or other methods without spinning or weaving, forming a cloth-like or fiber-structured material;

[0034] Step 9: Feed, mix and open fiber raw materials of different properties, varieties or batches separately, or feed, mix and open together, so that the compressed fiber blocks in the fiber package are loosened into small fiber bundles through mechanical impact and tearing; further mix the fibers that have been initially opened so that different fibers can be fully mixed; further open the mixed fibers to form a mixed fiber layer for combing by a carding machine.

[0035] The preparation method of the plant fiber non-woven fabric, the plant fiber is a filament or flocculent material generated by combining cellulose with various nutrients, has the functions of supporting, connecting, wrapping, filling and the like for plants, and is widely present in plant stems, roots, fruits and fruit shells. Synthetic fibers or natural fibers are rolled into a web shape, and then friction and static electricity are generated between the fibers through stretching, impact or compression to form a fiber web, and finally reinforced through processes such as hot pressing or post-treatment. The main tasks of combing are: further loosening the fibers and removing impurities; further mixing the fiber raw materials evenly; combing the blocky tufts into bundles, and then combing them into single fibers; and combing the fibers into a web. The double doffer carding machine can make the double-layer fiber web overlap evenly; the carding machine with a shuffling mechanism can make the fibers of the fiber web arranged randomly, reducing the strength difference in the longitudinal and transverse directions of the product. The mixed fibers are evenly fed from the air pressure cotton box by the feeding roller through the cotton feeding plate and the licker-in roller to the breast cylinder, and the carding unit on the breast cylinder performs preliminary carding on the fibers; then they are fed into the main cylinder by the licker-in roller, and the multiple groups of carding units on the main cylinder fully card the fibers; the carded fibers are partially stripped by the upper and lower doffers respectively, and after being condensed and shuffled, they are introduced into the upper and lower net curtains and overlapped into a double-layer web.

Claims

1. A method for preparing a plant fiber nonwoven fabric, characterized in that: The plant fiber non-woven fabric includes: Brazilian eucalyptus, cotton, flax, bamboo, etc. Their fibers can be made into non-woven fabrics through non-woven technology. Plant fiber is a thick-walled tissue widely distributed in seed plants. Its cells are slender, with sharp ends, thick secondary walls, and often have single pits on the walls. There is generally no living protoplast when mature. Plant fiber is a filamentous or flocculent substance generated by the combination of cellulose and various nutrients. It has the functions of supporting, connecting, wrapping, filling, etc. for plants. It is widely present in plant stems, roots, fruits, and fruit shells; The specific preparation method comprises the following steps: Step (1), fully drying polylactic acid in a vacuum drying oven at 60° C., mixing with cotton stalk fiber, flax fiber and polyamide fiber through a high-speed mixer to obtain a plant fiber mixture; melting the plant fiber mixture through screw extrusion, controlling the working temperature at 90° C. and the rotation speed at 55 r / min; and then spraying the plant fiber through a spinneret hole to form polylactic acid fiber; Step (2), Brazilian eucalyptus wood is mainly divided into softwood pulp and hardwood pulp. The softwood pulp fiber is long and thin, generally about 2.56-4.08 mm in length, 40.9-50.4 μm in width, and its aspect ratio is generally below 70. The softwood pulp fiber is relatively pure, with less impurities and a low pentose content of about 9%-12%. The fiber is not easy to absorb water and swell, has a high beating degree, and is not easy to break; the hardwood pulp fiber is thick and short; Step (3), Brazilian eucalyptus wood fiber has a unique style that is significantly different from cotton, wood fiber fabrics and plain fiber fabrics. It has excellent wear resistance, no pilling, high moisture absorption, quick drying, high air permeability, and drape. It feels smooth and plump, as soft as silk. It is mildew-proof, moth-proof and antibacterial, cool and comfortable to wear, and has the effect of beauty and skin care. It has excellent dyeing performance, bright luster, and good natural antibacterial effect and environmental protection. Step (5), in the process of manufacturing chemical pulp of Brazilian eucalyptus wood fiber, the principle is to retain cellulose and part of hemicellulose to the greatest extent, and lignin is the part to be removed as much as possible. When extracting cellulose and hemicellulose, the molecular structure of lignin is basically destroyed and discharged together with the wastewater generated by the pulping process; Step (6), rolling the synthetic fibers or natural fibers into a web shape, and then generating friction and electrostatic effects between the fibers by stretching, impacting or compressing to form a fiber web, and finally strengthening it by heat pressing or post-treatment; Step (7), wood has inherent conductivity and transmission properties. The cross-section of wood fiber is highly hollow and covered with irregular pores of various sizes. It can absorb and evaporate a large amount of water in an instant. Its water absorption is three times that of cotton. Step (8), the sheet, web or pad product etc. is made by combining oriented or randomly arranged fibers by friction, cohesion or bonding, or a combination of these methods. The sheet, web or pad product is a cloth-like, fiber-structured material formed by consolidating the fiber web together by mechanical, chemical, thermal or other methods without using traditional weaving methods such as spinning and weaving; Step (9), feeding, mixing, and opening fiber raw materials of different properties, different varieties, or different batches separately, or feeding, mixing, and opening together, so that the compressed fiber blocks in the fiber package are loosened into small fiber bundles through mechanical impact and tearing; further mixing the fibers that have been initially opened so that different fibers can be fully mixed; further opening the mixed fibers to form a mixed fiber layer for combing by a carding machine.

2. The method for preparing a plant fiber nonwoven fabric according to claim 1, characterized in that: The cellulose and various nutrients grow into single-cell fibers through seed epidermal cells, such as cotton and kapok. Bast fiber: a single fiber or technical fiber obtained from the phloem of some plants. Such as: flax, ramie, jute, bamboo fiber, leaf fiber: it is a craft fiber obtained from the leaves or sheaths of some plants. Such as: sisal, abaca, fruit fiber: fiber obtained from the fruits of some plants. Such as: coconut fiber.

3. The method for preparing a plant fiber nonwoven fabric according to claim 1, characterized in that: In the step (2), the length is generally about 0.8-1.08 mm, the aspect ratio is within 60, and it contains more impurities. The finished product has relatively low strength, is relatively loose, has a high bulk thickness, and has a high pentose content, generally 21%-24%. It has strong absorption performance and is easy to crush into pulp. Therefore, the thickness and density of products produced by different wood pulps will be different.

4. The method for preparing a plant fiber nonwoven fabric according to claim 1, characterized in that: In step (8), compressed air is used as a medium for conveying fibers and a means of control. The specific process is as follows: fibers are conveyed to the upper cotton storage box through the cotton inlet under the action of airflow, and the airflow is led out from the exhaust pipe from the airflow outlets on both sides of the upper cotton storage box, and the fibers fall into the upper cotton storage box. If the height of the upper cotton storage box storing fibers remains unchanged, the pressure remains unchanged; if there are too many fibers, the airflow outlet will be covered more, the air discharge pressure will increase, and the pressure of the upper cotton storage box will increase. After the pressure increase signal is fed back, it will control the upper device to reduce the fiber feeding amount.

5. The method for preparing a plant fiber nonwoven fabric according to claim 1, characterized in that: In the step (5), the black liquor produced contains a large amount of suspended solids, organic pollutants and toxic substances, which will cause serious pollution if directly discharged into the water body. In order to solve the problem of papermaking black liquor, lignin sulfonate can be prepared by using precipitants such as lime, calcium chloride, basic lead acetate, etc. through precipitation, separation, drying and other processes.

6. The method for preparing a plant fiber nonwoven fabric according to claim 1, characterized in that: In the step (6), the solvent used for solution polymerization can dissolve both monomers and polymers, and the obtained polymerization solution is directly used for spinning. The solvents used for solution polymerization include dimethylformamide, dimethyl sulfoxide, sodium thiocyanate and zinc chloride. The polymerization time using the first two organic solvents is generally more than 10 hours, but the concentration of the spinning solution is higher due to its strong dissolving power, the spinning speed can be appropriately increased, the solvent recovery is also relatively simple, and the obtained fiber has better performance.

7. The method for preparing a plant fiber nonwoven fabric according to claim 1, characterized in that: In step (7), the function of wood fiber textiles to keep warm in winter and cool in summer is unmatched by other fibers. In summer and autumn, they are cool and breathable. In winter and spring, they are warm and comfortable and can help eliminate excess heat and moisture in the body, preventing people from getting irritated or dry.