CN111809396B - High-performance fiber presoaking process - Google Patents

High-performance fiber presoaking process Download PDF

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Publication number
CN111809396B
CN111809396B CN202010514333.1A CN202010514333A CN111809396B CN 111809396 B CN111809396 B CN 111809396B CN 202010514333 A CN202010514333 A CN 202010514333A CN 111809396 B CN111809396 B CN 111809396B
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fiber
parts
polyvinyl alcohol
prepreg
drying
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CN111809396A (en
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马俊
杨建军
马国栋
马亚田
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Anhui Ansai New Material Co ltd
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Anhui Ansai New Material Co ltd
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    • DTEXTILES; PAPER
    • D06TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
    • D06MTREATMENT, NOT PROVIDED FOR ELSEWHERE IN CLASS D06, OF FIBRES, THREADS, YARNS, FABRICS, FEATHERS OR FIBROUS GOODS MADE FROM SUCH MATERIALS
    • D06M15/00Treating fibres, threads, yarns, fabrics, or fibrous goods made from such materials, with macromolecular compounds; Such treatment combined with mechanical treatment
    • D06M15/19Treating fibres, threads, yarns, fabrics, or fibrous goods made from such materials, with macromolecular compounds; Such treatment combined with mechanical treatment with synthetic macromolecular compounds
    • D06M15/37Macromolecular compounds obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
    • D06M15/55Epoxy resins
    • DTEXTILES; PAPER
    • D06TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
    • D06MTREATMENT, NOT PROVIDED FOR ELSEWHERE IN CLASS D06, OF FIBRES, THREADS, YARNS, FABRICS, FEATHERS OR FIBROUS GOODS MADE FROM SUCH MATERIALS
    • D06M13/00Treating fibres, threads, yarns, fabrics or fibrous goods made from such materials, with non-macromolecular organic compounds; Such treatment combined with mechanical treatment
    • D06M13/10Treating fibres, threads, yarns, fabrics or fibrous goods made from such materials, with non-macromolecular organic compounds; Such treatment combined with mechanical treatment with compounds containing oxygen
    • D06M13/11Compounds containing epoxy groups or precursors thereof
    • DTEXTILES; PAPER
    • D06TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
    • D06MTREATMENT, NOT PROVIDED FOR ELSEWHERE IN CLASS D06, OF FIBRES, THREADS, YARNS, FABRICS, FEATHERS OR FIBROUS GOODS MADE FROM SUCH MATERIALS
    • D06M13/00Treating fibres, threads, yarns, fabrics or fibrous goods made from such materials, with non-macromolecular organic compounds; Such treatment combined with mechanical treatment
    • D06M13/10Treating fibres, threads, yarns, fabrics or fibrous goods made from such materials, with non-macromolecular organic compounds; Such treatment combined with mechanical treatment with compounds containing oxygen
    • D06M13/184Carboxylic acids; Anhydrides, halides or salts thereof
    • D06M13/192Polycarboxylic acids; Anhydrides, halides or salts thereof
    • DTEXTILES; PAPER
    • D06TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
    • D06MTREATMENT, NOT PROVIDED FOR ELSEWHERE IN CLASS D06, OF FIBRES, THREADS, YARNS, FABRICS, FEATHERS OR FIBROUS GOODS MADE FROM SUCH MATERIALS
    • D06M13/00Treating fibres, threads, yarns, fabrics or fibrous goods made from such materials, with non-macromolecular organic compounds; Such treatment combined with mechanical treatment
    • D06M13/322Treating fibres, threads, yarns, fabrics or fibrous goods made from such materials, with non-macromolecular organic compounds; Such treatment combined with mechanical treatment with compounds containing nitrogen
    • D06M13/325Amines
    • D06M13/342Amino-carboxylic acids; Betaines; Aminosulfonic acids; Sulfo-betaines
    • DTEXTILES; PAPER
    • D06TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
    • D06MTREATMENT, NOT PROVIDED FOR ELSEWHERE IN CLASS D06, OF FIBRES, THREADS, YARNS, FABRICS, FEATHERS OR FIBROUS GOODS MADE FROM SUCH MATERIALS
    • D06M15/00Treating fibres, threads, yarns, fabrics, or fibrous goods made from such materials, with macromolecular compounds; Such treatment combined with mechanical treatment
    • D06M15/19Treating fibres, threads, yarns, fabrics, or fibrous goods made from such materials, with macromolecular compounds; Such treatment combined with mechanical treatment with synthetic macromolecular compounds
    • D06M15/21Macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds
    • D06M15/327Macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds of unsaturated alcohols or esters thereof
    • D06M15/333Macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds of unsaturated alcohols or esters thereof of vinyl acetate; Polyvinylalcohol
    • DTEXTILES; PAPER
    • D06TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
    • D06MTREATMENT, NOT PROVIDED FOR ELSEWHERE IN CLASS D06, OF FIBRES, THREADS, YARNS, FABRICS, FEATHERS OR FIBROUS GOODS MADE FROM SUCH MATERIALS
    • D06M15/00Treating fibres, threads, yarns, fabrics, or fibrous goods made from such materials, with macromolecular compounds; Such treatment combined with mechanical treatment
    • D06M15/19Treating fibres, threads, yarns, fabrics, or fibrous goods made from such materials, with macromolecular compounds; Such treatment combined with mechanical treatment with synthetic macromolecular compounds
    • D06M15/37Macromolecular compounds obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
    • D06M15/59Polyamides; Polyimides
    • DTEXTILES; PAPER
    • D06TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
    • D06MTREATMENT, NOT PROVIDED FOR ELSEWHERE IN CLASS D06, OF FIBRES, THREADS, YARNS, FABRICS, FEATHERS OR FIBROUS GOODS MADE FROM SUCH MATERIALS
    • D06M2101/00Chemical constitution of the fibres, threads, yarns, fabrics or fibrous goods made from such materials, to be treated
    • D06M2101/16Synthetic fibres, other than mineral fibres
    • D06M2101/18Synthetic fibres consisting of macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds
    • D06M2101/24Polymers or copolymers of alkenylalcohols or esters thereof; Polymers or copolymers of alkenylethers, acetals or ketones

Abstract

The invention discloses a high-performance fiber prepreg process, which comprises the following steps of: unreeling and drying the fiber; immersing the dried fiber into swelling liquid for 25-40s, quick-freezing the swelled fiber to-30 ℃, and drying under-0.1 Mpa to obtain swelled fiber; the invention overcomes the defects of the prior art, obviously improves the bonding strength of the epoxy resin adhesive and the fiber, and enhances the tensile resistance of the fiber by immersing the swelling fiber into the prepreg for 10-15s and then drying at 100-120 ℃ to obtain the high-performance fiber.

Description

High-performance fiber presoaking process
Technical Field
The invention relates to the technical field of fiber production, and in particular belongs to a high-performance fiber prepreg process.
Background
The solution impregnation method is a method in which each component of a resin matrix is dissolved in a solvent having a low boiling point in a predetermined ratio to form a solution having a predetermined concentration, and then a fiber bundle or a fabric is passed through the resin matrix solution at a predetermined speed to impregnate a predetermined amount of the resin matrix, and the method is required to have a step of removing the solvent. The solution impregnation method has the advantages that the reinforcing material is easy to be impregnated by the resin matrix, so that thin prepreg can be manufactured, thick prepreg can be manufactured, and the manufacturing cost of equipment is relatively low; however, the solvent is required to be removed or recovered in a drying oven, and the improper treatment may cause combustion or environmental pollution, and the prepreg may have a certain amount of solvent remaining, which may cause voids to be formed during molding, and may affect the performance of the material. The method is similar to the solution impregnation method, but the method still has the problems that the bonding strength of the prepreg after solidification is insufficient with the carbon fiber, the mechanical property of the carbon fiber after the prepreg treatment is poor, and pores exist on the surface.
Disclosure of Invention
The invention aims to provide a high-performance fiber prepreg process, which solves the problems of poor bonding strength between a prepreg and a fiber and poor mechanical properties of the prepreg fiber in the prior art.
In order to solve the problems, the technical scheme adopted by the invention is as follows:
a high performance fiber prepreg process comprising the steps of:
s1, unreeling and drying fibers;
s2, immersing the dried fiber into swelling liquid for 25-40S, quick-freezing the swelled fiber to-30 ℃, and drying under-0.1 Mpa to obtain swelled fiber;
s3, immersing the swelling fiber into the prepreg for 10-15S, and then drying at 100-120 ℃ to obtain the high-performance fiber.
Wherein, when the swelling fiber is immersed in the prepreg in the step S3, ultrasonic wave is applied by using an ultrasonic cleaner with power of 800W.
The swelling liquid is prepared by mixing the following raw materials in parts by weight: 150 parts of water, 75 parts of ethanol and 8 parts of amine dendritic polymer.
Wherein the amine dendritic polymer is polyamide.
Wherein the prepreg is mixed epoxy resin.
Wherein the mixed epoxy resin consists of the following raw materials in parts by weight: 50-60 parts of epoxy resin glue, 1-3 parts of propylene oxide butyl ether and 5-8 parts of modified polyvinyl alcohol fiber.
The preparation method of the modified polyvinyl alcohol fiber comprises the following steps: dispersing 1 part of polyvinyl alcohol fiber in 20 parts of DMF solution containing 1 part of oxalyl chloride, heating to 40 ℃, stirring for reacting for 10 hours, filtering and drying to obtain the acyl chloride polyvinyl alcohol fiber, dispersing the acyl chloride polyvinyl alcohol fiber in 30 parts of carbon tetrachloride solution containing 2 parts of alpha-aminopropionic acid and 0.5 part of sodium carbonate, stirring and mixing for 4 hours at 25 ℃, filtering and washing to obtain the alpha-aminopropionic acid modified polyvinyl alcohol fiber.
Compared with the prior art, the invention has the following implementation effects:
1. according to the invention, the swelling technology is adopted to swell the fiber, the swelling liquid adopts the mixed liquid of ethanol and water containing dendritic polymers, the ethanol and the water can effectively remove soluble impurities and dust on the surface of the fiber, meanwhile, burrs on the surface of the fiber are soaked, and the dendritic polymers enter the burrs on the surface of the fiber, so that the burrs on the surface of the fiber are spread, and then, under the actions of quick freezing and vacuum drying, a rough structure is formed on the surface of the fiber.
2. The surface of the fiber after swelling contains dendritic polymer polyamide, and the amino and acyl in the polyamide have strong affinity with the ether group and epoxy functional group of propylene oxide butyl ether in the mixed epoxy resin, so that the epoxy resin glue can fully impregnate the surface layer structure of the fiber, and simultaneously, under the catalysis of the polyamide, the mixed epoxy resin is solidified, so that the bonding strength of the epoxy resin glue and the fiber is obviously improved, and the tensile resistance of the fiber is enhanced;
3. the surface of the modified polyvinyl alcohol fiber is provided with carboxyl, and the carboxyl is subjected to crosslinking reaction with epoxy resin in the curing process of the epoxy resin glue, so that the polyvinyl alcohol fiber can be tightly combined with the epoxy resin glue, and meanwhile, the polyvinyl alcohol fiber plays a role in reinforcing the epoxy resin glue, so that the epoxy resin glue is not easy to break when the fiber is stressed, and the mechanical property of the fiber is enhanced.
4. The prepreg of the process adopts epoxy resin prepreg, no solvent is used, and high-temperature curing is adopted after the prepreg is adopted, so that the occurrence of pores on the surface of the fiber after the prepreg is avoided.
Detailed Description
The following description of the technical solutions in the embodiments of the present invention will be clear and complete, and it is obvious that the described embodiments are only 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.
The fiber of the invention uses carbon fiber with the diameter of 30um, and the polyamide is sourced from Xuzhou Teng engineering plastics Co.
Example 1
The presoaking process of the high-performance fiber comprises the following steps:
firstly, unreeling the fiber, drying at 60 ℃ for 20min, and removing water in the fiber; and preparing modified polyvinyl alcohol fibers, dispersing 1kg of polyvinyl alcohol fibers with the diameter of 100nm and the length of 5um in 20kg of DMF solution containing oxalyl chloride, heating to 40 ℃, stirring and reacting for 10 hours, filtering and drying to obtain acyl chloride polyvinyl alcohol fibers, dispersing the acyl chloride polyvinyl alcohol fibers in 30kg of carbon tetrachloride solution containing 2kg of alpha-aminopropionic acid and 0.5kg of sodium carbonate, stirring and mixing for 4 hours at 25 ℃, filtering and washing to obtain the alpha-aminopropionic acid modified polyvinyl alcohol fibers.
Then, the dried fiber was immersed in a raw material consisting of the following weight kg: in a swelling liquid prepared by mixing 150kg of water, 75kg of ethanol and 8kg of amine dendritic polymer polyamide, swelling for 30s, quick-freezing the swelled fiber to-30 ℃, and drying under-0.1 Mpa to obtain swelled fiber;
finally, immersing the swelling fiber into a prepreg, wherein the prepreg is mixed epoxy resin by using 800W power ultrasonic for 10s, and the mixed epoxy resin is composed of the following raw materials in parts by weight: 50kg of epoxy resin glue, 2kg of propylene oxide butyl ether and 6kg of modified polyvinyl alcohol fiber. And then drying at 100 ℃ to obtain the high-performance fiber.
Example 2
The difference from example 1 is that 800W power ultrasound is used for 15s for immersing the swelling fiber in a prepreg, which is a mixed epoxy resin composed of the following raw materials by weight kg: 60kg of epoxy resin glue, 3kg of propylene oxide butyl ether and 8kg of modified polyvinyl alcohol fiber. And then drying at 120 ℃ to obtain the high-performance fiber.
Comparative example 1
The difference from example 1 is that the swelling liquid does not contain amine-type dendrimer polyamide.
Comparative example 2
The difference from example 1 is that the mixed epoxy resin does not contain propylene oxide butyl ether.
Comparative example 3
The difference from example 1 is that the modified polyvinyl alcohol fibers are replaced with polyvinyl alcohol fibers.
The high performance fibers of examples 1-2 and comparative examples 1-3 were tested for tensile properties according to the test method in the national standard GB/T26749-2011 carbon fiber, the tensile properties of the dipped yarn, and the results are shown in the following table:
example 1 Example 2 Comparative example 1 Comparative example 2 Comparative example 3
Tensile modulus (GPa) 13.4 15.1 8.7 11.6 10.8
As can be seen from the tensile modulus, the polyamide in the swelling liquid plays a key role in improving the tensile property of the fiber by the presoaking process, and meanwhile, the propylene oxide butyl ether and the modified polyvinyl alcohol fiber effectively improve the tensile property of the fiber.
Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made therein without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.

Claims (1)

1. A high performance fiber prepreg process comprising the steps of:
s1, unreeling and drying fibers;
s2, immersing the dried fiber into swelling liquid for 25-40S, quick-freezing the swelled fiber to-30 ℃, and drying under-0.1 Mpa to obtain swelled fiber;
s3, immersing the swelling fiber into the prepreg for 10-15S, and then drying at 100-120 ℃ to obtain high-performance fiber;
in the step S3, when the swelling fiber is immersed in the prepreg, ultrasonic cleaning is performed by using an ultrasonic cleaner;
the swelling liquid is prepared by mixing the following raw materials in parts by weight: 150 parts of water, 75 parts of ethanol and 8 parts of amine dendritic polymer;
the amine dendritic polymer is polyamide;
the prepreg is mixed epoxy resin;
the mixed epoxy resin consists of the following raw materials in parts by weight: 50-60 parts of epoxy resin glue, 1-3 parts of propylene oxide butyl ether and 5-8 parts of modified polyvinyl alcohol fibers;
the preparation method of the modified polyvinyl alcohol fiber comprises the following steps: dispersing 1 part of polyvinyl alcohol fiber in 20 parts of DMF solution containing 1 part of oxalyl chloride, heating to 40 ℃, stirring for reacting for 10 hours, filtering and drying to obtain the acyl chloride polyvinyl alcohol fiber, dispersing the acyl chloride polyvinyl alcohol fiber in 30 parts of carbon tetrachloride solution containing 2 parts of alpha-aminopropionic acid and 0.5 part of sodium carbonate, stirring and mixing for 4 hours at 25 ℃, filtering and washing to obtain the alpha-aminopropionic acid modified polyvinyl alcohol fiber.
CN202010514333.1A 2020-06-08 2020-06-08 High-performance fiber presoaking process Active CN111809396B (en)

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Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102348735A (en) * 2009-03-24 2012-02-08 东丽株式会社 Epoxy resin composition for fiber-reinforced composite material, prepreg, and fiber-reinforced composite material
CN104292749A (en) * 2013-07-19 2015-01-21 味之素株式会社 Resin composition
CN104684975A (en) * 2012-09-28 2015-06-03 东丽株式会社 Prepreg and carbon fiber reinforced composite material
CN106164168A (en) * 2014-04-10 2016-11-23 赫克塞尔合成有限公司 The improvement of composite
CN108219375A (en) * 2017-12-31 2018-06-29 厦门大学 Surface modified carbon fiber prepreg material based on graphene oxide and preparation method thereof
CN109575334A (en) * 2018-11-27 2019-04-05 哈尔滨工业大学 A kind of shape memory epoxy resin prepreg and preparation method thereof

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP5780367B2 (en) * 2013-08-07 2015-09-16 東レ株式会社 Epoxy resin composition, prepreg and fiber reinforced composite material

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102348735A (en) * 2009-03-24 2012-02-08 东丽株式会社 Epoxy resin composition for fiber-reinforced composite material, prepreg, and fiber-reinforced composite material
CN104684975A (en) * 2012-09-28 2015-06-03 东丽株式会社 Prepreg and carbon fiber reinforced composite material
CN104292749A (en) * 2013-07-19 2015-01-21 味之素株式会社 Resin composition
CN106164168A (en) * 2014-04-10 2016-11-23 赫克塞尔合成有限公司 The improvement of composite
CN108219375A (en) * 2017-12-31 2018-06-29 厦门大学 Surface modified carbon fiber prepreg material based on graphene oxide and preparation method thereof
CN109575334A (en) * 2018-11-27 2019-04-05 哈尔滨工业大学 A kind of shape memory epoxy resin prepreg and preparation method thereof

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