Water-phase sizing product based on catechol derivative modified polymer and method for rapidly modifying organic fibers by using water-phase sizing product

Abstract

The invention relates to the field of interface modification of organic fiber materials, and discloses a water-phase sizing product based on a catechol derivative modified polymer and a method for rapidly modifying organic fibers by using the water-phase sizing product. The modified polymer is prepared from a catechol derivative modified acrylate monomer and an acrylate compound through thermal-initiated free radical polymerization. According to a water-phase sizing product based on the catechol derivative, key variables such as the pH value, the polymer structure, the polymer concentration and the ion concentration in a sizing system are accurately regulated and controlled, and the modification speed of organic fibers is effectively regulated and controlled by utilizing the synergistic effect of the variables. Finally, rapid and effective sizing modification treatment on the organic fibers within 1-10 s is achieved.

Description

Technical Field

[0001] The invention belongs to the technical field of organic fiber surface modification, and relates to a preparation method of an aqueous phase sizing product based on a catechol derivative modified polymer and a method for modifying organic fibers. Background Art

[0002] Organic fibers, such as aramid fibers, have symmetrical and regular molecular structures and contain a large number of rigid groups, showing excellent mechanical properties such as high strength, high modulus, and impact resistance. Therefore, they are widely used in the field of composite materials as reinforcements. However, the high rigidity and high orientation of the molecular chain of organic fibers also lead to a lack of chemically active groups on the fiber surface, which further leads to poor interfacial bonding between organic fibers and epoxy resins, which limits the widespread application of fiber composites. Therefore, surface treatment of organic fibers to improve their interfacial bonding performance with epoxy resin bases is an urgent problem to be solved.

[0003] A variety of modification methods for organic fibers have been reported, including physical modification, chemical modification, and surface structure construction. These methods have been extensively studied and applied in the field of organic fibers, but these modification methods are cumbersome and complex, usually causing damage to the mechanical properties of the fiber itself, and the modification process is cumbersome and complex. The literature (Mussel-Inspired Surface Chemistry for Multifunctional Coatings [J]. Science, 2007, 318 (5849): 426-430.) reported a method of forming a multifunctional polymer coating by simply dipping in a dopamine aqueous solution. This method can be used to self-polymerize dopamine to the surface of the material for modification, thereby improving the interfacial bonding performance of the modified material. Dopamine functionalization provides a simple and universal modification idea for organic fibers. The literature (Surface Modification of Aramid Fibers by Bio-Inspired Poly (dopamine) and Epoxy Functionalized Silane Grafting [J]. ACS Applied Materials & Interfaces, 2014, 6 (23): 21730-21738.) reports a method for modifying dopamine-functionalized organic fibers. By simply immersing the organic fibers in a dopamine solution at room temperature, a thin surface-adherent polydopamine film can be formed on the surface of the organic fibers, thereby effectively improving the interfacial properties of the organic fibers. The modification process is gentle and simple, and does not damage the fibers themselves. However, the method of modifying organic fibers with dopamine is usually time-consuming, often requiring more than ten hours or even several days to complete, which is difficult to meet the needs of continuous and rapid in-situ modification of aramid fibers in actual industrial production. The Chinese patent application number CN202311012544.5 provides an aqueous sizing modified organic fiber and a preparation method thereof, and discloses a method for modifying fibers with a polymer based on a catechol structure, wherein the polymer is dissolved in an acetic acid buffer solution to prepare a sizing solution, and then the organic fiber is immersed in the sizing solution for 10 to 60 seconds to complete the surface modification of the organic fiber, which to a certain extent solves the demand for rapid modification of organic fibers. However, although this method has made certain progress in improving the modification speed of organic fibers, there is still room for further optimization of the modification speed in the large-scale industrial production process of organic fibers. For a continuous online modification process, the modification speed is a key factor in determining whether it can demonstrate a competitive advantage in actual industrial applications. Therefore, if the modification process of organic fibers can be further accelerated, the production capacity of modified fibers will be significantly improved, thereby bringing greater economic benefits. In view of this, this application is hereby proposed. Summary of the invention

[0004] The purpose of the present invention is to solve the problems existing in the prior art and provide an aqueous sizing product based on a catechol derivative-modified polymer and a method for rapidly modifying organic fibers.

[0005] To achieve the above object, the technical solution adopted by the present invention is as follows:

[0006] A water-phase sizing product based on a catechol derivative-modified polymer is disclosed. The pH value, polymer structure, polymer concentration, ion concentration and other variables in the water-phase sizing product are adjusted to an optimal ratio. Through the synergistic effect of multiple variables, the water-phase sizing product can modify organic fibers within 1 to 10 seconds. The interface shear strength between the organic fibers modified by the water-phase sizing and the epoxy resin is 50 to 80 MPa.

[0007] The preparation method of the catechol derivative-modified polymer comprises: mixing the catechol derivative-modified acrylate monomer, acrylate derivative and free radical initiator in an organic solvent, and initiating free radical polymerization through heating reaction to generate the target polymer.

[0008] The catechol derivative-modified acrylic ester monomers include norepinephrine, droxidopa, methyldopamine, dihydroxyphenylacrylate and 5-hydroxydopamine.

[0009] The free radical initiator includes azobisisobutyronitrile, azobisisoheptanenitrile, dimethyl azobisisobutyrate, azobisisobutylamidine hydrochloride or dibenzoyl peroxide.

[0010] The organic solvent includes: ethyl acetate, methanol, N,N-dimethylformamide, N,N-dimethylacetamide, tetrahydrofuran or n-hexane.

[0011] The reaction temperature of the free radical polymerization reaction is 60-70° C., and the reaction time is 4-6 hours.

[0012] Based on the optimization of the modification speed of the aqueous sizing product, the configuration of the finally optimized aqueous sizing product is as follows: 5-hydroxydopa monomer is selected as the final polymer monomer, and the polymer concentration is 0.5-10 mg / mL; acetate buffer solution is selected as the acidic buffer solution, and the pH range is 3.5-5.5; sodium chloride is selected as the inorganic salt, and the ion concentration is 300-900 mM.

[0013] The aqueous sizing product changes the ratio of variables such as pH value, polymer structure, polymer concentration, ion concentration, etc. in the buffer solution, and through the synergistic effect of multiple variables, the modification time of organic fibers in the aqueous sizing product is regulated, and finally the sizing modification treatment of organic fibers is successfully achieved within 1 to 10 seconds.

[0014] A continuous sizing and modification method for organic fibers based on a finally optimized aqueous sizing product can achieve surface modification of organic fibers within 1 to 10 seconds.

[0015] The continuous sizing and modification treatment method of organic fiber is to pass through a sizing tank filled with a water-phase sizing product at a speed of 100 to 1000 m / h through an online production line of organic fiber, and then pass through a washing tank and an oven, and then be rolled up after drying to obtain a finished organic fiber. The time of passing through the sizing tank is 1 to 10 seconds.

[0016] Principle of the invention:

[0017] The aqueous sizing product of the present invention forms a highly synergistic mechanism of action through precise regulation of multiple key variables, significantly improving the modification speed of organic fibers. The coordination between pH value, polymer structure, polymer concentration, and ion concentration enables these variables to act together on the self-adhesion process of the catechol derivative modified polymer, ensuring the rapid sizing modification treatment of the fiber within 1 to 10 seconds. The key is that these variables jointly optimize the adhesion speed of the aqueous sizing product through synergistic action.

[0018] In the process of optimizing aqueous sizing products, the key lies in the synergistic effect between various variables to significantly improve the adhesion speed. First, the regulation of pH value is crucial. By adjusting the pH value, the ionization state of the amino and hydroxyl groups in the catechol derivative-modified polymer can be changed, thereby affecting its hydrogen bonding and cation-π interaction with the organic fiber surface. When the pH value is in the optimal range, the polymer can bind to the fiber surface more efficiently and reduce the adhesion time. This precise pH regulation lays the foundation for the synergistic effect of other variables, ensuring that the polymer can quickly and effectively modify the fiber surface. Secondly, the optimization of polymer structure is also an important part of the synergistic effect. By selecting the right catechol derivative, the polymer can provide more active binding sites and enhance the adhesion effect with the fiber surface. Among them, the structure of trihydroxycatechol derivatives can cooperate with the regulation of pH value to ensure the binding with the active sites of aramid fiber in the most favorable intermolecular state. In addition, the regulation of polymer concentration also has a significant synergistic effect with other variables. The appropriate concentration not only ensures that the polymer forms a uniform and tight coating on the fiber surface, but also prevents excessive accumulation caused by too high concentration or insufficient adhesion caused by too low concentration. The optimized concentration range enables catechol derivative-modified polymers to achieve the best adsorption effect in the shortest time. Finally, the regulation of ion concentration further enhances the adhesion effect of the polymer through cation-π interaction between ions and π electrons in the polymer. The change in ion concentration interacts with the regulation of pH value and polymer structure, ultimately synergistically improving the adhesion speed.

[0019] By optimizing pH value, polymer structure, concentration and ion concentration, the aqueous sizing product of the present invention successfully achieves the synergistic effect of various variables, ensuring that the catechol derivative modified polymer can quickly and stably form a uniform coating on the fiber surface. This optimization process improves the modification efficiency of the aqueous sizing product, enables rapid modification of organic fibers within 1 to 10 seconds, and effectively improves the interface performance.

[0020] Beneficial effects:

[0021] (1) The water-phase sizing product prepared by the present invention is obtained by optimizing multiple variables such as polymer structure, polymer concentration, pH value and ion concentration, and utilizing the synergistic effect of multiple variables to optimize the optimal modification conditions of the water-phase sizing product on organic fibers, and finally the modification treatment of the organic fibers can be completed within 1 to 10 seconds.

[0022] (2) The aqueous sizing product prepared by the present invention can be applied to the production line of organic fibers to achieve continuous online in-situ modification of large quantities of organic fibers. The interface properties of the modified organic fibers are significantly improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a graph showing the change in interfacial shear strength between aramid fiber and epoxy resin after modification by the aqueous sizing product in Example 1.

[0024] Figure 2 This is a graph showing the change in interfacial shear strength between glass fiber and epoxy resin after modification of Example 2 with a water-phase sizing product.

[0025] Figure 3 This is a graph showing the change in interfacial shear strength between polyester fiber and epoxy resin after modification by the aqueous sizing product in Example 3.

[0026] Figure 4 This is a graph showing the change in interfacial shear strength between aramid fiber and epoxy resin after modification with an aqueous sizing product containing 5-hydroxydopa polymer in Example 17. DETAILED DESCRIPTION

[0027] The present invention will be further described below in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not intended to limit the scope of the present invention. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms fall within the scope limited by the appended claims of the application equally.

[0028] The test method involved in the present invention is as follows:

[0029] Interface shear strength: The microsphere embedding method was used to evaluate the interface bonding strength between the fiber and the resin. The sample preparation steps are as follows: First, bisphenol A epoxy resin and epoxyamine curing agent were mixed evenly in a ratio of 2.88:1, and then vacuumed for 30 minutes to remove bubbles in the mixture. Next, double-sided tape was attached to both sides of the polytetrafluoroethylene plate, and a single aramid fiber monofilament was carefully selected from the aramid fiber bundle, straightened and fixed one by one on the polytetrafluoroethylene plate. Then, a 1mL syringe was used to carefully drop the prepared epoxy resin onto the aramid monofilament, so that the epoxy resin formed resin beads on the monofilament. Subsequently, the prepared sample was cured at 80°C for 3 hours to obtain a sample for the monofilament pull-out test. The above-prepared resin beads were observed under an optical microscope, and those resin beads that just passed through the midpoint of the aramid monofilament were selected. The diameters of these beads were recorded and numbered by comparing the scale. Ensure that the embedding length of epoxy resin and aramid fiber is moderate. The embedding length should be controlled between 0.25mm and 0.45mm. If it is too long, it will easily cause the fiber itself to break. If it is too short, the mold of the universal testing machine cannot be used to fix the resin ball. Finally, the selected resin ball is tested for single-filament pull-out using the universal testing machine. The fixture loading rate is set to 2mm / min. The maximum pull-out force required to pull the epoxy resin ball and the aramid fiber monofilament apart is recorded to calculate the interface shear strength. The specific calculation formula is as follows

[0030]

[0031] Wherein, F is the external load, unit: Newton; d is the fiber diameter, unit: micron; L is the resin embedding length, unit: millimeter.

[0032] In each example, organic fiber monofilaments selected from organic fiber multifilaments were used for the experiments.

[0033] Example 1

[0034] This embodiment provides an aqueous sizing product based on a catechol derivative-modified polymer and a method for rapidly modifying aramid fibers.

[0035] Among them, the preparation method of the catechol derivative modified polymer is: add azobisisobutyronitrile (molar percentage is 0.1%), methyl dopamine, and 2-aminoethyl methacrylate to the reaction solvent of DMF (total monomer concentration is 0.6 mmol / ml), react at 75°C for 5 hours under a nitrogen atmosphere, and add the solution dropwise into a poor solvent. The precipitated product is the catechol derivative modified polymer provided in this embodiment.

[0036] An aqueous sizing product based on a catechol derivative modified polymer comprises: an acetic acid buffer solution, sodium chloride and a catechol derivative modified polymer. The concentration of the catechol derivative modified polymer is 0.5 mg / mL, the pH value of the aqueous sizing product is 3.5, and the ion concentration of sodium chloride is 300 mM. The aqueous sizing product is obtained by the above method.

[0037] A method for rapid modification of aramid fiber based on an aqueous sizing product, the specific steps are as follows: passing the aramid fiber bundle through a sizing tank filled with the aqueous sizing solution at a speed of 100 m / h, soaking for 10 seconds, then passing through a washing tank, and finally drying and rolling to obtain the aramid fiber modified by the aqueous sizing product.

[0038] The obtained aqueous sizing product is modified into aramid fiber, such as Figure 1 As shown, the interfacial bonding strength between it and epoxy resin reaches 60MPa from 48MPa of untreated.

[0039] Example 2

[0040] This embodiment provides an aqueous sizing product based on a catechol derivative-modified polymer and a method for rapidly modifying glass fiber.

[0041] Among them, the preparation method of the catechol derivative modified polymer is: adding azobisisobutyronitrile (molar percentage of 0.1%), droxidopamine, and 2-aminoethyl methacrylate to a reaction solvent of DMF (total monomer concentration of 0.6 mmol / ml), reacting at 75° C. for 5 hours under a nitrogen atmosphere, and adding the solution dropwise into a poor solvent. The precipitated product is the catechol derivative modified polymer provided in this embodiment.

[0042] An aqueous sizing product based on a catechol derivative modified polymer comprises: an acetic acid buffer solution, sodium chloride and a catechol derivative modified polymer. The concentration of the catechol derivative modified polymer is 2.5 mg / mL, the pH value of the aqueous sizing product is 4.0, and the ion concentration of sodium chloride is 400 mM. The aqueous sizing product is obtained by the above method.

[0043] A method for rapid modification of glass fiber based on an aqueous sizing product, the specific steps of which are as follows: passing a glass fiber bundle through a sizing tank filled with the aqueous sizing liquid at a speed of 100 m / h, soaking for 8 seconds, then passing through a water washing tank, and finally drying and rolling to obtain glass fiber modified by the aqueous sizing product.

[0044] The obtained aqueous sizing product is modified into glass fiber, such as Figure 2 As shown, the interfacial bonding strength between it and epoxy resin reaches 35MPa from 25MPa without treatment.

[0045] Example 3

[0046] This embodiment provides an aqueous sizing product based on a catechol derivative-modified polymer and a method for rapidly modifying polyester fibers.

[0047] Among them, the preparation method of the catechol derivative modified polymer is: adding azobisisobutyronitrile (molar percentage of 0.1%), norepinephrine, and 2-aminoethyl methacrylate to a reaction solvent of DMF (total monomer concentration of 0.6 mmol / ml), reacting at 75° C. for 5 hours under a nitrogen atmosphere, and adding the solution dropwise into a poor solvent. The precipitated product is the catechol derivative modified polymer provided in this embodiment.

[0048] An aqueous sizing product based on a catechol derivative modified polymer comprises: an acetic acid buffer solution, sodium chloride and a catechol derivative modified polymer. The concentration of the catechol derivative modified polymer is 4.5 mg / mL, the pH value of the aqueous sizing product is 4.5, and the ion concentration of sodium chloride is 500 mM. The aqueous sizing product is obtained by the above method.

[0049] A method for rapidly modifying polyester fibers based on an aqueous sizing product, the specific steps of which are as follows: passing a polyester fiber bundle through a sizing tank filled with the aqueous sizing solution at a speed of 100 m / h, soaking for 6 seconds, then passing through a washing tank, and finally drying and rolling to obtain polyester fibers modified by the aqueous sizing product.

[0050] The polyester fiber modified by the aqueous sizing product is as follows: Figure 3 As shown, the interfacial bonding strength between it and epoxy resin reaches 20 MPa from 13 MPa without treatment.

[0051] Example 4

[0052] This embodiment provides an aqueous sizing product based on a catechol derivative-modified polymer and a method for rapidly modifying aramid fibers.

[0053] The preparation method of the catechol derivative modified polymer is as follows: azobisisobutyronitrile (0.1% by mole), dihydroxyphenyl acrylate, and 2-aminoethyl methacrylate are added to a DMF reaction solvent (total monomer concentration is 0.6 mmol / ml), reacted at 75° C. for 5 h under a nitrogen atmosphere, and the solution is added dropwise into a poor solvent. The precipitated product is the catechol derivative modified polymer provided in this embodiment.

[0054] An aqueous sizing product based on a catechol derivative modified polymer comprises: an acetic acid buffer solution, sodium chloride and a catechol derivative modified polymer. The concentration of the catechol derivative modified polymer is 6.5 mg / mL, the pH value of the aqueous sizing product is 5.0, and the ion concentration of sodium chloride is 600 mM. The aqueous sizing product is obtained by the above method.

[0055] A method for rapid modification of aramid fiber based on an aqueous sizing product, the specific steps of which are as follows: passing the aramid fiber bundle through a sizing tank filled with the aqueous sizing solution at a speed of 100 m / h, soaking for 4 seconds, then passing through a washing tank, and finally drying and rolling to obtain the aramid fiber modified by the aqueous sizing product.

[0056] The interface bonding strength between the aramid fiber modified by the aqueous sizing product and the epoxy resin increases from 45 MPa before treatment to 53 MPa.

[0057] Example 5

[0058] This embodiment provides an aqueous sizing product based on a catechol derivative-modified polymer and a method for rapidly modifying aramid fibers.

[0059] Among them, the preparation method of the catechol derivative modified polymer is: adding azobisisobutyronitrile (molar percentage of 0.1%), 5-hydroxydopamine, and 2-aminoethyl methacrylate to a reaction solvent of DMF (total monomer concentration of 0.6 mmol / ml), reacting at 75° C. for 5 hours under a nitrogen atmosphere, and adding the solution dropwise into a poor solvent. The precipitated product is the catechol derivative modified polymer provided in this embodiment.

[0060] An aqueous sizing product based on a catechol derivative modified polymer comprises: an acetic acid buffer solution, sodium chloride and a catechol derivative modified polymer. The concentration of the catechol derivative modified polymer is 8.5 mg / mL, the pH value of the aqueous sizing product is 5.5, and the ion concentration of sodium chloride is 700 mM. The aqueous sizing product is obtained by the above method.

[0061] A method for rapid modification of aramid fiber based on an aqueous sizing product, the specific steps are as follows: passing the aramid fiber bundle through a sizing tank filled with the aqueous sizing solution at a speed of 100 m / h, soaking for 2 seconds, then passing through a washing tank, and finally drying and rolling to obtain the aramid fiber modified by the aqueous sizing product.

[0062] The interface bonding strength between the aramid fiber modified by the aqueous sizing product and the epoxy resin increases from 45 MPa before treatment to 62 MPa.

[0063] Example 6

[0064] This embodiment provides an aqueous sizing product based on a catechol derivative-modified polymer and a method for rapidly modifying glass fiber.

[0065] Among them, the preparation method of the catechol derivative modified polymer is: add azobisisobutyronitrile (molar percentage is 0.1%), methyl dopamine, and 2-aminoethyl methacrylate to the reaction solvent of DMF (total monomer concentration is 0.6 mmol / ml), react at 75°C for 5 hours under a nitrogen atmosphere, and add the solution dropwise into a poor solvent. The precipitated product is the catechol derivative modified polymer provided in this embodiment.

[0066] An aqueous sizing product based on a catechol derivative modified polymer comprises: an acetic acid buffer solution, sodium chloride and a catechol derivative modified polymer. The concentration of the catechol derivative modified polymer is 10 mg / mL, the pH value of the aqueous sizing product is 4.5, and the ion concentration of sodium chloride is 800 mM. The aqueous sizing product is obtained by the above method.

[0067] A method for rapid modification of glass fiber based on an aqueous sizing product, the specific steps of which are as follows: passing a glass fiber bundle through a sizing tank filled with the aqueous sizing liquid at a speed of 100 m / h, soaking for 1 second, then passing through a water washing tank, and finally drying and rolling to obtain glass fiber modified by the aqueous sizing product.

[0068] The interface bonding strength between the glass fiber modified by the prepared aqueous sizing product and the epoxy resin increases from 25 MPa before treatment to 32 MPa.

[0069] Example 7

[0070] This embodiment provides an aqueous sizing product based on a catechol derivative-modified polymer and a method for rapidly modifying aramid fibers.

[0071] The preparation method of the catechol derivative modified polymer is as follows: azobisisobutyronitrile (0.1% by mole), dihydroxyphenyl acrylate, and 2-aminoethyl methacrylate are added to a DMF reaction solvent (total monomer concentration is 0.6 mmol / ml), reacted at 75° C. for 5 h under a nitrogen atmosphere, and the solution is added dropwise into a poor solvent. The precipitated product is the catechol derivative modified polymer provided in this embodiment.

[0072] An aqueous sizing product based on a catechol derivative modified polymer comprises: an acetic acid buffer solution, sodium chloride and a catechol derivative modified polymer. The concentration of the catechol derivative modified polymer is 5 mg / mL, the pH value of the aqueous sizing product is 3.5, and the ion concentration of sodium chloride is 900 mM. The aqueous sizing product is obtained by the above method.

[0073] A method for rapid modification of aramid fiber based on an aqueous sizing product, the specific steps of which are as follows: passing the aramid fiber bundle through a sizing tank filled with the aqueous sizing solution at a speed of 100 m / h, soaking for 5 seconds, then passing through a washing tank, and finally drying and rolling to obtain the aramid fiber modified by the aqueous sizing product.

[0074] The interface bonding strength between the aramid fiber modified by the aqueous sizing product and the epoxy resin increases from 45 MPa before treatment to 59 MPa.

[0075] Example 8

[0076] This embodiment provides an aqueous sizing product based on a catechol derivative-modified polymer and a method for rapidly modifying aramid fibers.

[0077] Among them, the preparation method of the catechol derivative modified polymer is: adding azobisisobutyronitrile (molar percentage of 0.1%), 5-hydroxydopamine, and 2-aminoethyl methacrylate to a reaction solvent of DMF (total monomer concentration of 0.6 mmol / ml), reacting at 75° C. for 5 hours under a nitrogen atmosphere, and adding the solution dropwise into a poor solvent. The precipitated product is the catechol derivative modified polymer provided in this embodiment.

[0078] An aqueous sizing product based on a catechol derivative modified polymer comprises: an acetic acid buffer solution, sodium chloride and a catechol derivative modified polymer. The concentration of the catechol derivative modified polymer is 1 mg / mL, the pH value of the aqueous sizing product is 5.0, and the ion concentration of sodium chloride is 800 mM. The aqueous sizing product is obtained by the above method.

[0079] A method for rapid modification of aramid fiber based on an aqueous sizing product, the specific steps are as follows: passing the aramid fiber bundle through a sizing tank filled with the aqueous sizing solution at a speed of 100 m / h, soaking for 10 seconds, then passing through a washing tank, and finally drying and rolling to obtain the aramid fiber modified by the aqueous sizing product.

[0080] The interface bonding strength between the aramid fiber modified by the aqueous sizing product and the epoxy resin increases from 45 MPa before treatment to 68 MPa.

[0081] Example 9

[0082] This embodiment provides an aqueous sizing product based on a catechol derivative-modified polymer and a method for rapidly modifying aramid fibers.

[0083] Among them, the preparation method of the catechol derivative modified polymer is: adding azobisisobutyronitrile (molar percentage of 0.1%), 5-hydroxydopamine, and 2-aminoethyl methacrylate to a reaction solvent of DMF (total monomer concentration of 0.6 mmol / ml), reacting at 75° C. for 5 hours under a nitrogen atmosphere, and adding the solution dropwise into a poor solvent. The precipitated product is the catechol derivative modified polymer provided in this embodiment.

[0084] An aqueous sizing product based on a catechol derivative modified polymer comprises: an acetic acid buffer solution, sodium chloride and a catechol derivative modified polymer. The concentration of the catechol derivative modified polymer is 5 mg / mL, the pH value of the aqueous sizing product is 4.0, and the ion concentration of sodium chloride is 600 mM. The aqueous sizing product is obtained by the above method.

[0085] A method for rapid modification of aramid fiber based on an aqueous sizing product, the specific steps are as follows: passing the aramid fiber bundle through a sizing tank filled with the aqueous sizing solution at a speed of 100 m / h, soaking for 10 seconds, then passing through a washing tank, and finally drying and rolling to obtain the aramid fiber modified by the aqueous sizing product.

[0086] The interface bonding strength between the aramid fiber modified by the aqueous sizing product and the epoxy resin increases from 45 MPa before treatment to 76 MPa.

[0087] Example 10

[0088] This embodiment provides an aqueous sizing product based on a catechol derivative-modified polymer and a method for rapidly modifying aramid fibers.

[0089] The preparation method of the catechol derivative modified polymer is as follows: azobisisobutyronitrile (0.1% by mole), dihydroxyphenyl acrylate, and 2-aminoethyl methacrylate are added to a DMF reaction solvent (total monomer concentration is 0.6 mmol / ml), reacted at 75° C. for 5 h under a nitrogen atmosphere, and the solution is added dropwise into a poor solvent. The precipitated product is the catechol derivative modified polymer provided in this embodiment.

[0090] An aqueous sizing product based on a catechol derivative modified polymer comprises: an acetic acid buffer solution, sodium chloride and a catechol derivative modified polymer. The concentration of the catechol derivative modified polymer is 5 mg / mL, the pH value of the aqueous sizing product is 4.0, and the ion concentration of sodium chloride is 600 mM. The aqueous sizing product is obtained by the above method.

[0091] A method for rapid modification of aramid fiber based on an aqueous sizing product, the specific steps are as follows: passing the aramid fiber bundle through a sizing tank filled with the aqueous sizing solution at a speed of 100 m / h, soaking for 10 seconds, then passing through a washing tank, and finally drying and rolling to obtain the aramid fiber modified by the aqueous sizing product.

[0092] The interface bonding strength between the aramid fiber modified by the prepared aqueous sizing product and the epoxy resin increases from 45 MPa before treatment to 64 MPa.

[0093] Embodiment 11

[0094] This embodiment provides an aqueous sizing product based on a catechol derivative-modified polymer and a method for rapidly modifying aramid fibers.

[0095] The preparation method of the catechol derivative modified polymer is as follows: azobisisobutyronitrile (0.1% by mole), dihydroxyphenyl acrylate, and 2-aminoethyl methacrylate are added to a DMF reaction solvent (total monomer concentration is 0.6 mmol / ml), reacted at 75° C. for 5 h under a nitrogen atmosphere, and the solution is added dropwise into a poor solvent. The precipitated product is the catechol derivative modified polymer provided in this embodiment.

[0096] An aqueous sizing product based on a catechol derivative modified polymer comprises: an acetic acid buffer solution, sodium chloride and a catechol derivative modified polymer. The concentration of the catechol derivative modified polymer is 5 mg / mL, the pH value of the aqueous sizing product is 4.0, and the ion concentration of sodium chloride is 600 mM. The aqueous sizing product is obtained by the above method.

[0097] A method for rapid modification of aramid fiber based on an aqueous sizing product, the specific steps are as follows: passing the aramid fiber bundle through a sizing tank filled with the aqueous sizing solution at a speed of 100 m / h, soaking for 10 seconds, then passing through a washing tank, and finally drying and rolling to obtain the aramid fiber modified by the aqueous sizing product.

[0098] The interface bonding strength between the aramid fiber modified by the prepared aqueous sizing product and the epoxy resin increases from 45 MPa before treatment to 64 MPa.

[0099] Example 12

[0100] This embodiment provides an aqueous sizing product based on a catechol derivative-modified polymer and a method for rapidly modifying glass fiber.

[0101] Among them, the preparation method of the catechol derivative modified polymer is: adding azobisisobutyronitrile (molar percentage of 0.1%), dihydroxyphenyl acrylate amine, and 2-aminoethyl methacrylate to a DMF reaction solvent (total monomer concentration is 0.6 mmol / ml), reacting at 75° C. for 5 hours under a nitrogen atmosphere, and adding the solution dropwise into a poor solvent. The precipitated product is the catechol derivative modified polymer provided in this embodiment.

[0102] An aqueous sizing product based on a catechol derivative modified polymer comprises: an acetic acid buffer solution, sodium chloride and a catechol derivative modified polymer. The concentration of the catechol derivative modified polymer is 9.5 mg / mL, the pH value of the aqueous sizing product is 5.0, and the ion concentration of sodium chloride is 500 mM. The aqueous sizing product is obtained by the above method.

[0103] A method for rapid modification of glass fiber based on an aqueous sizing product, the specific steps of which are as follows: passing a glass fiber bundle through a sizing tank filled with the aqueous sizing liquid at a speed of 100 m / h, soaking for 5 seconds, then passing through a water washing tank, and finally drying and rolling to obtain glass fiber modified by the aqueous sizing product.

[0104] The interface bonding strength between the glass fiber modified by the prepared aqueous sizing product and the epoxy resin increases from 25 MPa before treatment to 33 MPa.

[0105] Example 12

[0106] This embodiment provides an aqueous sizing product based on a catechol derivative-modified polymer and a method for rapidly modifying aramid fibers.

[0107] Among them, the preparation method of the catechol derivative modified polymer is: adding azobisisobutyronitrile (molar percentage of 0.1%), 5-hydroxydopamine, and 2-aminoethyl methacrylate to a reaction solvent of DMF (total monomer concentration of 0.6 mmol / ml), reacting at 75° C. for 5 hours under a nitrogen atmosphere, and adding the solution dropwise into a poor solvent. The precipitated product is the catechol derivative modified polymer provided in this embodiment.

[0108] An aqueous sizing product based on a catechol derivative modified polymer comprises: an acetic acid buffer solution, sodium chloride and a catechol derivative modified polymer. The concentration of the catechol derivative modified polymer is 2 mg / mL, the pH value of the aqueous sizing product is 3.5, and the ion concentration of sodium chloride is 300 mM. The aqueous sizing product is obtained by the above method.

[0109] A method for rapid modification of aramid fiber based on an aqueous sizing product, the specific steps are as follows: passing the aramid fiber bundle through a sizing tank filled with the aqueous sizing solution at a speed of 100 m / h, soaking for 2 seconds, then passing through a washing tank, and finally drying and rolling to obtain the aramid fiber modified by the aqueous sizing product.

[0110] The interface bonding strength between the aramid fiber modified by the aqueous sizing product and the epoxy resin increases from 45 MPa before treatment to 66 MPa.

[0111] Example 13

[0112] This embodiment provides an aqueous sizing product based on a catechol derivative-modified polymer and a method for rapidly modifying aramid fibers.

[0113] Among them, the preparation method of the catechol derivative modified polymer is: adding azobisisobutyronitrile (molar percentage of 0.1%), 5-hydroxydopamine, and 2-aminoethyl methacrylate to a reaction solvent of DMF (total monomer concentration of 0.6 mmol / ml), reacting at 75° C. for 5 hours under a nitrogen atmosphere, and adding the solution dropwise into a poor solvent. The precipitated product is the catechol derivative modified polymer provided in this embodiment.

[0114] An aqueous sizing product based on a catechol derivative modified polymer comprises: an acetic acid buffer solution, sodium chloride and a catechol derivative modified polymer. The concentration of the catechol derivative modified polymer is 3 mg / mL, the pH value of the aqueous sizing product is 4.0, and the ion concentration of sodium chloride is 500 mM. The aqueous sizing product is obtained by the above method.

[0115] A method for rapid modification of aramid fiber based on an aqueous sizing product, the specific steps of which are as follows: passing the aramid fiber bundle through a sizing tank filled with the aqueous sizing solution at a speed of 100 m / h, soaking for 4 seconds, then passing through a washing tank, and finally drying and rolling to obtain the aramid fiber modified by the aqueous sizing product.

[0116] The interface bonding strength between the aramid fiber modified by the aqueous sizing product and the epoxy resin increases from 45 MPa before treatment to 68 MPa.

[0117] Embodiment 14

[0118] This embodiment provides an aqueous sizing product based on a catechol derivative-modified polymer and a method for rapidly modifying aramid fibers.

[0119] Among them, the preparation method of the catechol derivative modified polymer is: adding azobisisobutyronitrile (molar percentage of 0.1%), 5-hydroxydopamine, and 2-aminoethyl methacrylate to a reaction solvent of DMF (total monomer concentration of 0.6 mmol / ml), reacting at 75° C. for 5 hours under a nitrogen atmosphere, and adding the solution dropwise into a poor solvent. The precipitated product is the catechol derivative modified polymer provided in this embodiment.

[0120] An aqueous sizing product based on a catechol derivative modified polymer comprises: an acetic acid buffer solution, sodium chloride and a catechol derivative modified polymer. The concentration of the catechol derivative modified polymer is 4 mg / mL, the pH value of the aqueous sizing product is 4.5, and the ion concentration of sodium chloride is 700 mM. The aqueous sizing product is obtained by the above method.

[0121] A method for rapid modification of aramid fiber based on an aqueous sizing product, the specific steps of which are as follows: passing the aramid fiber bundle through a sizing tank filled with the aqueous sizing solution at a speed of 100 m / h, soaking for 8 seconds, then passing through a washing tank, and finally drying and rolling to obtain the aramid fiber modified by the aqueous sizing product.

[0122] The interface bonding strength between the aramid fiber modified by the aqueous sizing product and the epoxy resin increases from 45 MPa before treatment to 68 MPa.

[0123] Embodiment 15

[0124] This embodiment provides an aqueous sizing product based on a catechol derivative-modified polymer and a method for rapidly modifying aramid fibers.

[0125] Among them, the preparation method of the catechol derivative modified polymer is: adding azobisisobutyronitrile (molar percentage of 0.1%), 5-hydroxydopamine, and 2-aminoethyl methacrylate to a reaction solvent of DMF (total monomer concentration of 0.6 mmol / ml), reacting at 75° C. for 5 hours under a nitrogen atmosphere, and adding the solution dropwise into a poor solvent. The precipitated product is the catechol derivative modified polymer provided in this embodiment.

[0126] An aqueous sizing product based on a catechol derivative modified polymer comprises: an acetic acid buffer solution, sodium chloride and a catechol derivative modified polymer. The concentration of the catechol derivative modified polymer is 5 mg / mL, the pH value of the aqueous sizing product is 5.0, and the ion concentration of sodium chloride is 900 mM. The aqueous sizing product is obtained by the above method.

[0127] A method for rapid modification of aramid fiber based on an aqueous sizing product, the specific steps are as follows: passing the aramid fiber bundle through a sizing tank filled with the aqueous sizing solution at a speed of 100 m / h, soaking for 10 seconds, then passing through a washing tank, and finally drying and rolling to obtain the aramid fiber modified by the aqueous sizing product.

[0128] The interface bonding strength between the aramid fiber modified by the aqueous sizing product and the epoxy resin increases from 45 MPa before treatment to 71 MPa.

[0129] Example 16

[0130] This embodiment provides an aqueous sizing product based on a catechol derivative-modified polymer and a method for rapidly modifying aramid fibers.

[0131] Among them, the preparation method of the catechol derivative modified polymer is: adding azobisisobutyronitrile (molar percentage of 0.1%), 5-hydroxydopamine, and 2-aminoethyl methacrylate to a reaction solvent of DMF (total monomer concentration of 0.6 mmol / ml), reacting at 75° C. for 5 hours under a nitrogen atmosphere, and adding the solution dropwise into a poor solvent. The precipitated product is the catechol derivative modified polymer provided in this embodiment.

[0132] An aqueous sizing product based on a catechol derivative modified polymer comprises: an acetic acid buffer solution, sodium chloride and a catechol derivative modified polymer. The concentration of the catechol derivative modified polymer is 6 mg / mL, the pH value of the aqueous sizing product is 5.5, and the ion concentration of sodium chloride is 600 mM. The aqueous sizing product is obtained by the above method.

[0133] A method for rapid modification of aramid fiber based on an aqueous sizing product, the specific steps of which are as follows: passing the aramid fiber bundle through a sizing tank filled with the aqueous sizing solution at a speed of 100 m / h, soaking for 5 seconds, then passing through a washing tank, and finally drying and rolling to obtain the aramid fiber modified by the aqueous sizing product.

[0134] The interface bonding strength between the aramid fiber modified by the aqueous sizing product and the epoxy resin increases from 45 MPa before treatment to 67 MPa.

[0135] Embodiment 17

[0136] This embodiment provides an aqueous sizing product based on a catechol derivative-modified polymer and a method for rapidly modifying aramid fibers.

[0137] Among them, the preparation method of the catechol derivative modified polymer is: adding azobisisobutyronitrile (molar percentage of 0.1%), 5-hydroxydopamine, and 2-aminoethyl methacrylate to a reaction solvent of DMF (total monomer concentration of 0.6 mmol / ml), reacting at 75° C. for 5 hours under a nitrogen atmosphere, and adding the solution dropwise into a poor solvent. The precipitated product is the catechol derivative modified polymer provided in this embodiment.

[0138] An aqueous sizing product based on a catechol derivative modified polymer comprises: an acetic acid buffer solution, sodium chloride and a catechol derivative modified polymer. The concentration of the catechol derivative modified polymer is 5 mg / mL, the pH value of the aqueous sizing product is 3.5, and the ion concentration of sodium chloride is 600 mM. The aqueous sizing product is obtained by the above method.

[0139] A method for rapid modification of aramid fiber based on an aqueous sizing product, the specific steps are as follows: passing the aramid fiber bundle through a sizing tank filled with the aqueous sizing solution at a speed of 100 m / h, soaking for 10 seconds, then passing through a washing tank, and finally drying and rolling to obtain the aramid fiber modified by the aqueous sizing product.

[0140] The obtained aqueous sizing product is modified into aramid fiber, such as Figure 4 As shown, the interfacial bonding strength between it and epoxy resin increases from 45 MPa to 75 MPa without treatment.

[0141] Embodiment 18

[0142] This embodiment provides an aqueous sizing product based on a catechol derivative-modified polymer and a method for rapidly modifying aramid fibers.

[0143] Among them, the preparation method of the catechol derivative modified polymer is: adding azobisisobutyronitrile (molar percentage of 0.1%), 5-hydroxydopamine, and 2-aminoethyl methacrylate to a reaction solvent of DMF (total monomer concentration of 0.6 mmol / ml), reacting at 75° C. for 5 hours under a nitrogen atmosphere, and adding the solution dropwise into a poor solvent. The precipitated product is the catechol derivative modified polymer provided in this embodiment.

[0144] An aqueous sizing product based on a catechol derivative modified polymer comprises: an acetic acid buffer solution, sodium chloride and a catechol derivative modified polymer. The concentration of the catechol derivative modified polymer is 0.5 mg / mL, the pH value of the aqueous sizing product is 3.5, and the ion concentration of sodium chloride is 600 mM. The aqueous sizing product is obtained by the above method.

[0145] A method for rapid modification of aramid fiber based on an aqueous sizing product, the specific steps are as follows: passing the aramid fiber bundle through a sizing tank filled with the aqueous sizing solution at a speed of 100 m / h, soaking for 10 seconds, then passing through a washing tank, and finally drying and rolling to obtain the aramid fiber modified by the aqueous sizing product.

[0146] The interface bonding strength between the aramid fiber modified by the prepared aqueous sizing product and the epoxy resin increases from 45 MPa before treatment to 55 MPa.

[0147] Embodiment 19

[0148] This embodiment provides an aqueous sizing product based on a catechol derivative-modified polymer and a method for rapidly modifying aramid fibers.

[0149] Among them, the preparation method of the catechol derivative modified polymer is: adding azobisisobutyronitrile (molar percentage of 0.1%), 5-hydroxydopamine, and 2-aminoethyl methacrylate to a reaction solvent of DMF (total monomer concentration of 0.6 mmol / ml), reacting at 75° C. for 5 hours under a nitrogen atmosphere, and adding the solution dropwise into a poor solvent. The precipitated product is the catechol derivative modified polymer provided in this embodiment.

[0150] An aqueous sizing product based on a catechol derivative modified polymer comprises: an acetic acid buffer solution, sodium chloride and a catechol derivative modified polymer. The concentration of the catechol derivative modified polymer is 10 mg / mL, the pH value of the aqueous sizing product is 5.5, and the ion concentration of sodium chloride is 600 mM. The aqueous sizing product is obtained by the above method.

[0151] A method for rapid modification of aramid fiber based on an aqueous sizing product, the specific steps are as follows: passing the aramid fiber bundle through a sizing tank filled with the aqueous sizing solution at a speed of 100 m / h, soaking for 10 seconds, then passing through a washing tank, and finally drying and rolling to obtain the aramid fiber modified by the aqueous sizing product.

[0152] The interface bonding strength between the aramid fiber modified by the prepared aqueous sizing product and the epoxy resin increases from 45 MPa before treatment to 70 MPa.

[0153] Embodiment 20

[0154] This embodiment provides an aqueous sizing product based on a catechol derivative-modified polymer and a method for rapidly modifying aramid fibers.

[0155] Among them, the preparation method of the catechol derivative modified polymer is: adding azobisisobutyronitrile (molar percentage of 0.1%), 5-hydroxydopamine, and 2-aminoethyl methacrylate to a reaction solvent of DMF (total monomer concentration of 0.6 mmol / ml), reacting at 75° C. for 5 hours under a nitrogen atmosphere, and adding the solution dropwise into a poor solvent. The precipitated product is the catechol derivative modified polymer provided in this embodiment.

[0156] An aqueous sizing product based on a catechol derivative modified polymer comprises: an acetic acid buffer solution, sodium chloride and a catechol derivative modified polymer. The concentration of the catechol derivative modified polymer is 5 mg / mL, the pH value of the aqueous sizing product is 4.0, and the ion concentration of sodium chloride is 400 mM. The aqueous sizing product is obtained by the above method.

[0157] A method for rapid modification of aramid fiber based on an aqueous sizing product, the specific steps are as follows: passing the aramid fiber bundle through a sizing tank filled with the aqueous sizing solution at a speed of 100 m / h, soaking for 10 seconds, then passing through a washing tank, and finally drying and rolling to obtain the aramid fiber modified by the aqueous sizing product.

[0158] The interface bonding strength between the aramid fiber modified by the aqueous sizing product and the epoxy resin increases from 45 MPa before treatment to 72 MPa.

[0159] Embodiment 21

[0160] This embodiment provides an aqueous sizing product based on a catechol derivative-modified polymer and a method for rapidly modifying aramid fibers.

[0161] Among them, the preparation method of the catechol derivative modified polymer is: adding azobisisobutyronitrile (molar percentage of 0.1%), 5-hydroxydopamine, and 2-aminoethyl methacrylate to a reaction solvent of DMF (total monomer concentration of 0.6 mmol / ml), reacting at 75° C. for 5 hours under a nitrogen atmosphere, and adding the solution dropwise into a poor solvent. The precipitated product is the catechol derivative modified polymer provided in this embodiment.

[0162] An aqueous sizing product based on a catechol derivative modified polymer comprises: an acetic acid buffer solution, sodium chloride and a catechol derivative modified polymer. The concentration of the catechol derivative modified polymer is 5 mg / mL, the pH value of the aqueous sizing product is 4.0, and the ion concentration of sodium chloride is 800 mM. The aqueous sizing product is obtained by the above method.

[0163] A method for rapid modification of aramid fiber based on an aqueous sizing product, the specific steps of which are as follows: passing the aramid fiber bundle through a sizing tank filled with the aqueous sizing solution at a speed of 100 m / h, soaking for 5 seconds, then passing through a washing tank, and finally drying and rolling to obtain the aramid fiber modified by the aqueous sizing product.

[0164] The interface bonding strength between the aramid fiber modified by the aqueous sizing product and the epoxy resin increases from 45 MPa before treatment to 67 MPa.

[0165] The proportions of the aqueous sizing solutions and sizing times of Examples 1 to 21 are shown in Table 1:

[0166] Table 1

[0167]

[0168]

Claims

1. An aqueous sizing product based on a catechol derivative modified polymer, characterized in that: It comprises an acidic buffer solution, a catechol derivative modified polymer and an inorganic salt, wherein the ratio of the catechol derivative modified polymer to the alkaline buffer solution is 0.5-10 mg:1 mL; The preparation method of the catechol derivative modified polymer is as follows: catechol derivative modified acrylate monomer, acrylate monomer and free radical initiator are placed in an organic solvent and mixed, and free radical polymerization is initiated by heating reaction to generate the target polymer, wherein the concentration of the free radical initiator is within 0.01% to 0.5% of the monomer mass. The catechol derivative-modified acrylic ester monomer is characterized in that the monomer structure includes at least one of norepinephrine, droxidopa, methyldopamine, dihydroxyphenylacrylate and 5-hydroxydopamine, and the preferred polymer concentration range is 0.5 to 10 mg / mL. The acidic buffer solution is characterized in that the acidic buffer solution includes acetic acid / sodium acetate buffer, citric acid-sodium hydroxide-hydrochloric acid buffer, disodium hydrogen phosphate-sodium dihydrogen phosphate buffer or aminoacetic acid-aminoacetate buffer, and the preferred pH range is within 3.5 to 5.

5. The inorganic salt is characterized in that the inorganic salt includes at least one of sodium chloride, magnesium chloride, potassium chloride, sodium sulfate and magnesium sulfate, and the preferred concentration range is 300-900 mM.

2. The acidic buffer solution according to claim 1, characterized in that: The acidic buffer solution is an acetic acid / sodium acetate buffer solution, and the preferred pH range is 3.5 to 5.

5.

3. The inorganic salt according to claim 1, characterized in that The inorganic salt is sodium chloride, and the preferred concentration range is 300-900 mM.

4. According to claims 1, 2, 3 and 4, in an acetate buffer solution with a pH of 3.5 to 5.5, a catechol derivative modified polymer prepared from a 5-hydroxydopamine monomer having a concentration of 300 to 900 mM sodium chloride and a polymer concentration of 0.5 to 10 mg / mL is fully mixed to obtain an optimized aqueous sizing product.

5. The aqueous sizing product according to claim 4, characterized in that: After the organic fiber is treated with the aqueous sizing product for only 1 to 10 seconds, the interfacial properties of the organic fiber are effectively improved.

6. A modification method for continuous sizing of organic fibers, characterized in that: After the organic fiber passes through the sizing tank containing the aqueous sizing product as claimed in claim 1, it continues to go through the steps of water washing and drying, and finally is rolled up to obtain the modified organic fiber, and the interface properties of the modified organic fiber are effectively improved.

7. The continuous sizing and modification method of organic fiber based on aqueous sizing product according to claim 7, characterized in that: The sizing line speed of organic fibers is 100-1000 m / h.

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