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CN118996671B - A kind of low melting point ultra short fiber and preparation method thereof - Google Patents

A kind of low melting point ultra short fiber and preparation method thereof Download PDF

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Publication number
CN118996671B
CN118996671B CN202411383382.0A CN202411383382A CN118996671B CN 118996671 B CN118996671 B CN 118996671B CN 202411383382 A CN202411383382 A CN 202411383382A CN 118996671 B CN118996671 B CN 118996671B
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short fiber
melting
mesoporous silica
low
master batch
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CN118996671A (en
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姚日远
陈祥
徐东昕
翟根林
王伟
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Yangzhou Petrochemical Co ltd
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Yangzhou Petrochemical Co ltd
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    • DTEXTILES; PAPER
    • D01NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
    • D01FCHEMICAL FEATURES IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS; APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OF CARBON FILAMENTS
    • D01F8/00Conjugated, i.e. bi- or multicomponent, artificial filaments or the like; Manufacture thereof
    • D01F8/04Conjugated, i.e. bi- or multicomponent, artificial filaments or the like; Manufacture thereof from synthetic polymers
    • D01F8/06Conjugated, i.e. bi- or multicomponent, artificial filaments or the like; Manufacture thereof from synthetic polymers with at least one polyolefin as constituent
    • DTEXTILES; PAPER
    • D01NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
    • D01DMECHANICAL METHODS OR APPARATUS IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS
    • D01D5/00Formation of filaments, threads, or the like
    • D01D5/28Formation of filaments, threads, or the like while mixing different spinning solutions or melts during the spinning operation; Spinnerette packs therefor
    • D01D5/30Conjugate filaments; Spinnerette packs therefor
    • D01D5/34Core-skin structure; Spinnerette packs therefor
    • DTEXTILES; PAPER
    • D01NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
    • D01FCHEMICAL FEATURES IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS; APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OF CARBON FILAMENTS
    • D01F1/00General methods for the manufacture of artificial filaments or the like
    • D01F1/02Addition of substances to the spinning solution or to the melt
    • D01F1/10Other agents for modifying properties
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02PCLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P70/00Climate change mitigation technologies in the production process for final industrial or consumer products
    • Y02P70/50Manufacturing or production processes characterised by the final manufactured product
    • Y02P70/62Manufacturing or production processes characterised by the final manufactured product related technologies for production or treatment of textile or flexible materials or products thereof, including footwear

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  • Engineering & Computer Science (AREA)
  • Textile Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Mechanical Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • Artificial Filaments (AREA)
  • Multicomponent Fibers (AREA)
  • Treatments For Attaching Organic Compounds To Fibrous Goods (AREA)

Abstract

The scheme relates to a low-melting-point ultra-short fiber and a preparation method thereof, and the low-melting-point ultra-short fiber is an ES composite fiber, and comprises a skin layer and a core layer, wherein the skin layer comprises PE and modified master batch, the core layer comprises PE, the modified master batch is used for carrying out amination modification on mesoporous silica first, hyperbranched polymer chains containing ester groups and carboxyl groups are prepared through active free radical polymerization, grafting reaction is carried out on the modified master batch and the mesoporous silica to form an organic whole, and then grafting polymerization is carried out on the modified master batch, PE and maleic anhydride in a reactive double-screw extruder under the initiation effect of an initiator. The application adopts polyolefin as main raw material to produce low-melting point ultra-short fiber, which is compared with polyester, the cost is effectively controlled, the softness is effectively improved, modified master batch is added in the cortex structure, the interaction force between PE molecular chains is weakened, the interaction force between crystals is weakened, the melting point of the cortex is effectively reduced, the production process is smooth, and the phenomena of pulp silk, floating silk, winding roller and the like are all in a controllable range.

Description

Low-melting-point ultrashort fiber and preparation method thereof
Technical Field
The invention relates to the field of composite fibers, in particular to a low-melting-point ultrashort fiber and a preparation method thereof.
Background
The fiber form and cut length of the ultra-short fiber are diversified, so that it can be widely used in various fields such as sanitary products, non-woven fabrics, paper making, etc. Different super-short fiber varieties are used for different application scenes, and the varieties are various, including polyester super-short fibers, polypropylene super-short fibers, aramid super-short fibers, glass fibers, ES composite fibers and the like.
In the production of some non-woven fabrics and dust-free papers, the fiber is required to have a lower melting point, and polyester composite fiber is usually used as the main material, and polyester with a lower melting point such as PET is adopted as a skin layer structure, wherein the melting point of the skin layer is lower than that of the core layer, and the fiber has the characteristics of low hot melting bonding temperature and rapid bonding. However, the low-melting-point polyester composite fiber contains isophthalic acid, and has the advantages of high cost, high rigidity, poor spinnability, poor fiber forming and relatively poor softness, and is limited in application in non-woven fabrics.
Disclosure of Invention
Aiming at the defects in the prior art, the invention adopts polyolefin as a main raw material to prepare the ultra-short composite fiber with low melting point.
In order to achieve the above purpose, the present invention provides the following technical solutions:
the low-melting-point ultra-short fiber is an ES composite fiber, and comprises a skin layer and a core layer, wherein the skin layer is made of PE and modified master batch;
the preparation process of the modified master batch comprises the following steps:
S1, dispersing mesoporous silica in a methane sulfonic acid aqueous solution, heating to 90 ℃, stirring, refluxing overnight, cooling, washing, filtering, then uniformly mixing with gamma-aminopropyl trimethoxysilane in water, heating to 50 ℃, stirring for 24h, cooling to room temperature, filtering, flushing with ethanol, and drying to obtain the aminated mesoporous silica;
S2, synthesizing a hyperbranched polymer through a RAFT system by taking vinyl acetate, ethyl acrylate and acrylic acid as monomers, AIBN as an initiator and xanthate containing terminal double bonds as a chain transfer agent;
S3, respectively dispersing and dissolving the products of the step S1 and the step S2 in tetrahydrofuran, then mixing the products, stirring and refluxing the mixture under nitrogen atmosphere overnight, then centrifugally separating, washing the obtained product with ethanol and water, and drying the product in vacuum to obtain hyperbranched polymer mesoporous silica;
S4, dissolving maleic anhydride and an initiator in tetrahydrofuran, then adding hyperbranched polymer mesoporous silica and PE, uniformly mixing, reacting and extruding through a reactive double-screw extruder, and granulating and drying to obtain the polymer.
In the process of preparing the modified master batch, firstly, the mesoporous silica is subjected to amination modification, amino active sites are formed on the surface of the mesoporous silica, amidation reaction and the like are carried out, secondly, hyperbranched polymer chains containing ester groups and carboxyl groups are prepared by active free radical polymerization, grafting reaction is carried out on the surface of the hyperbranched polymer chains by taking the aminated mesoporous silica as a template to form an organic whole, and then the organic whole and maleic anhydride are subjected to grafting polymerization with PE in a reactive double-screw extruder under the initiation of an initiator, so that the modified master batch taking PE as a carrier is formed, and the modified master batch has a mesoporous and three-dimensional network structure. Can reduce the intermolecular acting force of PE, reduce the interaction force between crystals, reduce the crystallinity and further reduce the melting point. The modified master batch and PE are mixed to have good dispersibility and compoundability, so that the phenomena of yarn floating and yarn breakage in the production process and yarn sizing in the post-spinning process caused by uneven mixing are avoided.
Further, the mass ratio of the skin layer to the core layer is 40-45:60-55, and the modified master batch accounts for 10-20wt% of the skin layer.
Further, the mesoporous silica is prepared by a sol-gel method by taking tetraethoxysilane as a silicon source and P123 as a template agent.
Further, in the step S1, the mass-volume ratio of the mesoporous silica to the gamma-aminopropyl trimethoxysilane is 1:1.
Further, in the step S2, the xanthate containing the terminal double bond is (2-ethoxydithio ester group) vinyl acetate, and the molar ratio of the vinyl acetate, the butyl acrylate, the acrylic acid, the AIBN and the xanthate containing the terminal double bond is 100:10-50:50-90:0.5:1.
Further, in the step S3, the usage ratio of the products in the step S1 to the step S2 is 0.05-0.1:1.
Further, in the step S4, the mass ratio of the maleic anhydride, the initiator, the hyperbranched polymer mesoporous silica and the PE is 5-10:0.5-1:1-5:90.
The invention further provides a preparation method of the low-melting-point ultrashort fiber, which comprises the following steps:
the pre-spinning process is that raw materials of the skin layer and the core layer respectively enter two screw extruders through two feed hoppers to be melted and extruded into melt, and after being filtered, the melt is precisely metered into a spinning box body through a metering pump to reach a spinning assembly, so as to form a precursor with a skin-core structure;
And the post spinning process is to cut the spun yarn bundle from the previous spinning and traversing into ultra-short fibers with the required size through an oil dipping tank, a steam preheating tank, a water bath tank, three drafting, an oiling roller, a crimping machine, a relaxation heat setting machine.
Compared with the prior art, the application has the beneficial effects that polyolefin is adopted as a main raw material to produce the low-melting-point ultra-short fiber, compared with polyester, the cost is effectively controlled, the softness is effectively improved, the modified master batch is added in the cortex structure, the modified master batch contains mesoporous silica and hyperbranched polymer chains, the modified master batch has a mesoporous and three-dimensional reticular structure, the entanglement of intermolecular chains is reduced, the interaction force among PE molecular chains is weakened, the interaction force among crystals is weakened, the melting point of the cortex is effectively reduced, the production process is smooth, and the phenomena of sizing, drifting and winding are less.
Detailed Description
The technical solutions of the present invention will be clearly and completely described in connection with the embodiments, and it is apparent that the described embodiments are some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
In addition, the technical features of the different embodiments of the present invention described below may be combined with each other as long as they do not collide with each other.
The embodiment of the invention relates to low-melting-point ultra-short fibers, which are ES composite fibers, and comprise a skin layer and a core layer, wherein the skin layer comprises PE and modified master batch, the core layer comprises PE, the mass ratio of the skin layer to the core layer is 40-45:60-55, and the modified master batch accounts for 10-20wt% of the skin layer.
The preparation process of the modified master batch comprises the following steps:
S1, 2g of template agent P123 is dissolved in hydrochloric acid solution, finally 4.5g of tetraethoxysilane is dropwise added, the mixture is stirred at 40 ℃ to form organosilicon sol, then the organosilicon sol is kept stand at 90 ℃ for 24 hours, and then the mesoporous silica is obtained through centrifugal separation and vacuum drying;
Dispersing 2g of mesoporous silica in 10ml of 5% methane sulfonic acid aqueous solution, heating to 90 ℃, stirring and refluxing for overnight, cooling, washing and filtering, then uniformly mixing with 2ml of gamma-aminopropyl trimethoxysilane in water, heating to 50 ℃, stirring for 24 hours, cooling to room temperature, filtering, flushing with ethanol, and drying to obtain the amino mesoporous silica;
S2, synthesizing a hyperbranched polymer through a RAFT system by taking 1 mol vinyl acetate, 200 mmol ethyl acrylate and 800 mmol acrylic acid as monomers, 5mmol AIBN as an initiator, and 10mmol xanthate ((2-ethoxydithio ester group) vinyl acetate containing terminal double bonds, prepared by referring to patent 201010223709. X) as a chain transfer agent;
S3, respectively dispersing and dissolving the products of the step S1 and the step S2 in tetrahydrofuran, then mixing the products, stirring and refluxing the mixture under nitrogen atmosphere overnight, then centrifugally separating, washing the obtained product with ethanol and water, and drying the product in vacuum to obtain hyperbranched polymer mesoporous silica;
S4, dissolving maleic anhydride and an initiator in tetrahydrofuran, then adding hyperbranched polymer mesoporous silica and PE, uniformly mixing, reacting and extruding through a reactive double-screw extruder, and granulating and drying to obtain the polymer. (the mass ratio of maleic anhydride, initiator, hyperbranched polymer mesoporous silica to PE is 5-10:0.5-1:1-5:90)
Under the condition that the rest conditions are unchanged, the mass ratio in the step S4 is adjusted to obtain the following modified master batch.
Sample 1, maleic anhydride, initiator, hyperbranched polymer mesoporous silica and PE in a mass ratio of 5:0.5:2:90;
Sample 2, maleic anhydride, initiator, hyperbranched polymer mesoporous silica and PE with a mass ratio of 7:0.6:3:90;
sample 3, maleic anhydride, initiator, hyperbranched polymer mesoporous silica and PE with a mass ratio of 8:0.8:5:90;
Sample 4 the mass ratio of maleic anhydride, initiator, hyperbranched polymer mesoporous silica and PE is 8:0.6:0:90.
The pre-spinning process comprises the steps of respectively feeding raw materials of a skin layer and a core layer into two screw extruders through two feed hoppers to be melted and extruded into melt, filtering, feeding the melt into a spinning box body through precise metering of a metering pump to reach a spinning assembly to form a precursor with a skin-core structure, wherein the mass ratio of the skin layer to the core layer is 40:60, and the proportion of modified master batch in the skin layer is 10 wt%.
And the post spinning process is to cut the spun yarn bundle from the previous spinning and traversing into ultra-short fibers with the required size through an oil dipping tank, a steam preheating tank, a water bath tank, three drafting, an oiling roller, a crimping machine, a relaxation heat setting machine.
Short fibers were prepared using different masterbatch bases in different proportions, and adverse phenomena such as winding and the like occurring in the preparation process were recorded, and are recorded in table 1.
TABLE 1
As can be seen from Table I, as the addition ratio of the masterbatch increases, the number of rolls increases, and the number of fly filaments and pulp filaments increases, but the overall production conditions were within an acceptable range, and the performance test was conducted on the short fibers produced at 15% of the addition amount of the masterbatch, and the results are shown in Table 2.
TABLE 2
As can be seen from Table 2, the addition of the modified masterbatch effectively reduces the sheath melting point to 109℃as compared to 127℃for the sheath melting point of conventional fibers, and meets the higher test requirements.
Although embodiments of the present invention have been disclosed above, it is not limited to the use of the description and embodiments, it is well suited to various fields of use for the invention, and further modifications may be readily apparent to those skilled in the art, and accordingly, the invention is not limited to the particular details without departing from the general concepts defined in the claims and the equivalents thereof.

Claims (8)

1. The low-melting-point ultra-short fiber is characterized by being an ES composite fiber, and comprising a skin layer and a core layer, wherein the skin layer is made of PE and modified master batch;
the preparation process of the modified master batch comprises the following steps:
s1, dispersing mesoporous silica in a methane sulfonic acid aqueous solution, heating to 90 ℃, stirring, refluxing overnight, cooling, washing, filtering, then uniformly mixing with gamma-aminopropyl trimethoxysilane in water, heating to 50 ℃, stirring for 24 hours, cooling to room temperature, filtering, flushing with ethanol, and drying to obtain the aminated mesoporous silica;
S2, synthesizing a hyperbranched polymer through a RAFT system by taking vinyl acetate, ethyl acrylate and acrylic acid as monomers, AIBN as an initiator and xanthate containing terminal double bonds as a chain transfer agent;
S3, respectively dispersing and dissolving the products of the step S1 and the step S2 in tetrahydrofuran, then mixing the products, stirring and refluxing the mixture under nitrogen atmosphere overnight, then centrifugally separating, washing the obtained product with ethanol and water, and drying the product in vacuum to obtain hyperbranched polymer mesoporous silica;
S4, dissolving maleic anhydride and an initiator in tetrahydrofuran, then adding hyperbranched polymer mesoporous silica and PE, uniformly mixing, reacting and extruding through a reactive double-screw extruder, and granulating and drying to obtain the polymer.
2. The low-melting-point ultra-short fiber according to claim 1, wherein the mass ratio of the sheath layer to the core layer is 40-45:60-55, and the modified masterbatch accounts for 10-20wt% of the sheath layer.
3. The low-melting point ultra-short fiber according to claim 1, wherein the mesoporous silica is prepared by a sol-gel method by using tetraethoxysilane as a silicon source and P123 as a template agent.
4. The low-melting point ultra-short fiber according to claim 1, wherein in the step S1, the mass-volume ratio of the mesoporous silica to the γ -aminopropyl trimethoxysilane is 1:1.
5. The low-melting-point ultra-short fiber according to claim 1, wherein in the step S2, the xanthate containing the terminal double bond is (2-ethoxydithio ester group) vinyl acetate, and the molar ratio of vinyl acetate, butyl acrylate, acrylic acid, AIBN and xanthate containing the terminal double bond is 100:10 to 50:50 to 90:0.5:1.
6. The low-melting-point ultra-short fiber according to claim 1, wherein in the step S3, the ratio of the products of the step S1 to the step S2 is 0.05 to 0.1:1.
7. The low-melting-point ultra-short fiber according to claim 1, wherein in the step S4, the mass ratio of maleic anhydride, initiator, hyperbranched polymer mesoporous silica and PE is 5-10:0.5-1:1-5:90.
8. The method for producing a low-melting point ultra-short fiber according to any one of claims 1 to 7, comprising the steps of:
the pre-spinning process is that raw materials of the skin layer and the core layer respectively enter two screw extruders through two feed hoppers to be melted and extruded into melt, and after being filtered, the melt is precisely metered into a spinning box body through a metering pump to reach a spinning assembly, so as to form a precursor with a skin-core structure;
And the post spinning process is to cut the spun yarn bundle from the previous spinning and traversing into ultra-short fibers with the required size through an oil dipping tank, a steam preheating tank, a water bath tank, three drafting, an oiling roller, a crimping machine, a relaxation heat setting machine.
CN202411383382.0A 2024-09-30 2024-09-30 A kind of low melting point ultra short fiber and preparation method thereof Active CN118996671B (en)

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Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0931815A (en) * 1995-05-18 1997-02-04 Chisso Corp Fiber aggregate and its production
CN112694759A (en) * 2020-12-21 2021-04-23 上饶市泰士特科技有限公司 Nano silicon dioxide modified low-density polyethylene composite material and preparation method thereof

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DK132191D0 (en) * 1991-07-05 1991-07-05 Danaklon As FIBERS AND MANUFACTURING THEREOF
JP3821256B2 (en) * 1996-11-22 2006-09-13 チッソ株式会社 Long fiber nonwoven fabric, method for producing the same, and absorbent article

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0931815A (en) * 1995-05-18 1997-02-04 Chisso Corp Fiber aggregate and its production
CN112694759A (en) * 2020-12-21 2021-04-23 上饶市泰士特科技有限公司 Nano silicon dioxide modified low-density polyethylene composite material and preparation method thereof

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