A modified glass fiber based on a lubricant and its use in epoxy pultrusion plates

Abstract

The application discloses a modified glass fiber based on a lubricant and application thereof in an epoxy pultrusion plate, and relates to the technical field of glass fibers.The application prepares a lubricant and a modified glass fiber based on the lubricant.Fatty alcohol polyoxyethylene ether, polyvinylpyrrolidone, triethanolamine borate and paraffin wax are used to enhance lubricating performance.Water-based polyurethane emulsion is added to form a continuous and tough protective film, which significantly improves the wear resistance and mechanical damage resistance of the glass fiber.The surface of the glass fiber is first subjected to low-temperature plasma treatment, so that the surface of the glass fiber becomes more microscopically rough, and the surface area is increased;then, tetraethyl orthosilicate is added to form nano silicon dioxide on the surface of the glass fiber, so that the surface roughness and acid and alkali resistance of the glass fiber are further increased;and then, the surface of the glass fiber is subjected to surface modification treatment by using amino branched polyamide, so that the compatibility of the glass fiber with polyamide resin is enhanced, and the mechanical properties of the pultrusion plate are improved.

Description

Technical Field

[0001] This invention relates to the field of glass fiber technology, specifically to a lubricant-based modified glass fiber and its application in epoxy pultruded sheets. Background Technology

[0002] Epoxy pultruded sheets, as an important glass fiber reinforced epoxy resin composite material product, have excellent mechanical properties and corrosion resistance, and are widely used in wind turbine blades, aerospace, automobile manufacturing and other fields.

[0003] When glass fiber is used as a reinforcing material in epoxy pultruded sheets, insufficient interfacial compatibility between the glass fiber and epoxy resin can lead to inadequate adhesion between the fiber and resin, affecting the overall performance of the composite material. Furthermore, glass fiber is susceptible to mechanical damage during pultrusion, resulting in decreased strength and toughness. Lubricants can improve the flowability and dispersion of glass fiber during pultrusion, reduce friction and damage between fibers, improve fiber integrity, and enhance the performance of epoxy pultruded sheets. Therefore, selecting a suitable lubricant that effectively improves the performance of glass fiber without negatively impacting the mechanical properties of the epoxy pultruded sheet is a pressing issue that needs to be addressed.

[0004] To address the aforementioned problems, this invention provides a lubricant-based modified glass fiber and its application in epoxy pultruded sheets. Summary of the Invention

[0005] The purpose of this invention is to provide a lubricant-based modified glass fiber and its application in epoxy pultruded sheets, in order to solve the problems raised in the prior art.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] A lubricant-based modified glass fiber, comprising the following steps:

[0008] S1: Take water-based polyurethane emulsion, add deionized water, stir evenly, add composite solution and polyamide solution, stir evenly, add coupling agent solution, stir evenly, and obtain lubricant;

[0009] S2: Take tetraethyl orthosilicate and ethanol, stir evenly, add sodium hydroxide solution to adjust the pH value to obtain tetraethyl orthosilicate solution; immerse the plasma-treated glass fiber in tetraethyl orthosilicate solution, react for 3-4 hours, take it out and dry it to obtain glass fiber A;

[0010] S3: Take amino-branched polyamide, deionized water and ethanol, stir evenly, add glass fiber A, heat to 60-62℃, react for 15-20 min, filter and dry to obtain glass fiber B;

[0011] S4: Immerse glass fiber B in lubricant, remove and dry to obtain modified glass fiber.

[0012] In a more optimized manner, in S1, the lubricant preparation method includes the following steps:

[0013] Step 1: Take fatty alcohol polyoxyethylene ether, polyvinylpyrrolidone, triethanolamine borate, paraffin, and deionized water, stir evenly to obtain a composite solution;

[0014] Step 2: Take water-based polyamide and deionized water, stir well to obtain a polyamide solution;

[0015] Step 3: Take the coupling agent, add deionized water, stir well, add pH adjuster until the pH of the aqueous solution is 5-7, stir well, and obtain the coupling agent solution;

[0016] Step 4: Take the water-based polyurethane emulsion, add deionized water, stir evenly, add the composite solution and polyamide solution, stir evenly, add the coupling agent solution, stir evenly, and obtain the lubricant.

[0017] In a more optimized manner, the composite solution contains the following components, by weight fraction: 6-8 parts fatty alcohol polyoxyethylene ether, 3-5 parts polyvinylpyrrolidone, 1-2 parts triethanolamine borate, 2-2.5 parts paraffin, and 100-105 parts deionized water.

[0018] Ideally, the mass ratio of the aqueous polyamide to deionized water is (10-15):100.

[0019] Ideally, the pH adjuster is any one or more of acetic acid, citric acid, and succinic acid.

[0020] More preferably, the coupling agent is coupling agent Y-9669 or coupling agent A-187.

[0021] In a more optimized manner, the preparation method of the plasma-treated glass fiber is as follows: take glass fiber, rinse the surface alternately with deionized water and acetone, and dry it to obtain cleaned glass fiber; put the cleaned glass fiber into a low-temperature plasma reactor, fill it with argon gas, and discharge it at a power of 80-85W for 3-4 minutes to obtain plasma-treated glass fiber.

[0022] A more optimized method for preparing the amino-branched polyamide is as follows: take diethylenetriamine, heat it at 50-55℃ for 2-3 hours, add succinic anhydride, raise the temperature to 140℃ and continue heating and stirring for 3-4 hours, cool, and obtain the amino-branched polyamide.

[0023] Application of a modified glass fiber in epoxy pultruded sheets.

[0024] Compared with the prior art, the beneficial effects of the present invention are:

[0025] 1. This invention prepares a lubricant and a modified glass fiber based on the lubricant. Fatty alcohol polyoxyethylene ether, polyvinylpyrrolidone, triethanolamine borate, and paraffin wax are used to enhance lubrication performance. The addition of an aqueous polyurethane emulsion forms a continuous and tough protective film, significantly improving the wear resistance and resistance to mechanical damage of the glass fiber.

[0026] 2. This invention first subjects the glass fiber surface to low-temperature plasma treatment, making the surface slightly rougher and increasing the surface area. Then, by adding tetraethyl orthosilicate to form nano-silica on the glass fiber surface, its surface roughness and acid and alkali resistance are further increased. Next, amino-branched polyamide is used to modify the glass fiber surface, improving the compatibility between the modified glass fiber and the lubricant. Simultaneously, amino groups are loaded onto the glass fiber, and these amino groups form chemical bonds with the polyamide resin in the pultruded plate substrate, enhancing the compatibility between the glass fiber and the polyamide resin, thereby improving the mechanical properties of the pultruded plate. Detailed Implementation

[0027] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0028] The sources and types of substances involved in this invention are not specifically limited. Exemplary examples include: coupling agent Y-9669, which can be purchased from Momentive; coupling agent A-187, which can be purchased from Momentive; glass fiber: diameter: 11-13μm, length: 3-20mm; waterborne polyamide: which can be purchased from Wenzhou Guoshibang Polymer Materials Co., Ltd., GSB; waterborne polyurethane emulsion: which can be purchased from Nanjing Chuhai New Materials Technology Co., Ltd., type: PU667.

[0029] Example 1: Preparation of a lubricant-based modified glass fiber, comprising the following steps:

[0030] Step 1: Preparation of Lubricant

[0031] Take 6g of fatty alcohol polyoxyethylene ether, 3g of polyvinylpyrrolidone, 1g of triethanolamine borate, 2g of paraffin, and 100mL of deionized water, stir well to obtain a composite solution.

[0032] The composite solution contains the following components by weight fraction: 7 parts fatty alcohol polyoxyethylene ether, 4 parts polyvinylpyrrolidone, 1.5 parts triethanolamine borate, 2.3 parts paraffin, and 102 parts deionized water;

[0033] Take 12g of aqueous polyamide and 100mL of deionized water, stir well to obtain a polyamide solution;

[0034] The mass ratio of waterborne polyamide to deionized water is 12:100;

[0035] Take 5g of coupling agent Y-9669 and 3g of coupling agent A-187, add 50mL of deionized water, stir well, add pH adjuster to make the pH of the aqueous solution 6, stir well to obtain coupling agent solution;

[0036] The pH adjuster is citric acid;

[0037] Take 25g of waterborne polyurethane emulsion, add 100mL of deionized water, stir well, add composite solution and polyamide solution, stir well, add coupling agent solution, stir well, and obtain lubricant.

[0038] Step 2: Preparation of modified glass fiber, including the following steps:

[0039] S1: Preparation of amino-branched polyamide:

[0040] Take 103g of diethylenetriamine, heat it at 52℃ for 2.5h, add 80g of succinic anhydride, raise the temperature to 140℃ and continue heating and stirring for 3.5h, cool, and obtain amino-branched polyamide;

[0041] S2: Plasma treatment:

[0042] Take glass fiber, cut it into 3-20mm fibers, rinse the surface twice with deionized water and acetone alternately, and dry it to obtain cleaned glass fiber; put the cleaned glass fiber into a low-temperature plasma reactor, fill it with argon gas at a pressure of 0.1MPa, and discharge it at a power of 80W for 3min to obtain plasma-treated glass fiber.

[0043] S3: Modification treatment:

[0044] Take 20g of tetraethyl orthosilicate and 100mL of ethanol, stir well, and add sodium hydroxide solution to adjust the pH to 11 to obtain a tetraethyl orthosilicate solution; immerse the plasma-treated glass fiber in the tetraethyl orthosilicate solution and react for 3.5h, then remove and dry to obtain glass fiber A;

[0045] Take 2g of amino-branched polyamide, 80mL of deionized water, and 20mL of ethanol, stir well, add 1g of glass fiber A, heat to 61℃, react for 18min, filter and dry to obtain glass fiber B.

[0046] Glass fiber B was immersed in a lubricant, then removed and dried to obtain modified glass fiber.

[0047] Example 2: Preparation of a lubricant-based modified glass fiber, comprising the following steps:

[0048] Step 1: Preparation of Lubricant

[0049] Take 6g of fatty alcohol polyoxyethylene ether, 3g of polyvinylpyrrolidone, 1g of triethanolamine borate, 2g of paraffin, and 100mL of deionized water, stir well to obtain a composite solution.

[0050] The composite solution contains the following components by weight fraction: 6 parts fatty alcohol polyoxyethylene ether, 3 parts polyvinylpyrrolidone, 1 part triethanolamine borate, 2 parts paraffin, and 100 parts deionized water.

[0051] Take 10g of aqueous polyamide and 100mL of deionized water, stir well to obtain a polyamide solution;

[0052] The mass ratio of waterborne polyamide to deionized water is 10:100;

[0053] Take 5g of coupling agent Y-9669 and 3g of coupling agent A-187, add 50mL of deionized water, stir well, add pH adjuster until the pH of the aqueous solution is 5, stir well to obtain coupling agent solution;

[0054] The pH adjuster is citric acid;

[0055] Take 25g of waterborne polyurethane emulsion, add 100mL of deionized water, stir well, add composite solution and polyamide solution, stir well, add coupling agent solution, stir well, and obtain lubricant.

[0056] Step 2: Preparation of modified glass fiber, including the following steps:

[0057] S1: Preparation of amino-branched polyamide:

[0058] Take 103g of diethylenetriamine, heat it at 50℃ for 2h, add 80g of succinic anhydride, raise the temperature to 140℃ and continue heating and stirring for 3h, cool it to obtain amino-branched polyamide;

[0059] S2: Plasma treatment:

[0060] Take glass fiber, cut it into 3-20mm fibers, rinse the surface twice with deionized water and acetone alternately, and dry it to obtain cleaned glass fiber; put the cleaned glass fiber into a low-temperature plasma reactor, fill it with argon gas at a pressure of 0.1MPa, and discharge it at a power of 80W for 3min to obtain plasma-treated glass fiber.

[0061] S3: Modification treatment:

[0062] Take 20g of tetraethyl orthosilicate and 100mL of ethanol, stir well, and add sodium hydroxide solution to adjust the pH value to 11 to obtain a tetraethyl orthosilicate solution; immerse the plasma-treated glass fiber in the tetraethyl orthosilicate solution, react for 3h, take it out and dry it to obtain glass fiber A.

[0063] Take 2g of amino-branched polyamide, 80mL of deionized water, and 20mL of ethanol, stir well, add 1g of glass fiber A, heat to 60℃, react for 15min, filter and dry to obtain glass fiber B.

[0064] Glass fiber B was immersed in a lubricant, then removed and dried to obtain modified glass fiber.

[0065] Example 3: Preparation of a lubricant-based modified glass fiber, comprising the following steps:

[0066] Step 1: Preparation of Lubricant

[0067] Take 6g of fatty alcohol polyoxyethylene ether, 3g of polyvinylpyrrolidone, 1g of triethanolamine borate, 2g of paraffin, and 100mL of deionized water, stir well to obtain a composite solution.

[0068] The composite solution contains the following components by weight fraction: 8 parts fatty alcohol polyoxyethylene ether, 5 parts polyvinylpyrrolidone, 2 parts triethanolamine borate, 2.5 parts paraffin, and 105 parts deionized water.

[0069] Take 15g of aqueous polyamide and 100mL of deionized water, stir well to obtain a polyamide solution;

[0070] The mass ratio of waterborne polyamide to deionized water is 15:100;

[0071] Take 5g of coupling agent Y-9669 and 3g of coupling agent A-187, add 50mL of deionized water, stir well, add pH adjuster until the pH of the aqueous solution is 7, stir well to obtain coupling agent solution;

[0072] The pH adjuster is succinic acid;

[0073] Take 25g of waterborne polyurethane emulsion, add 100mL of deionized water, stir well, add composite solution and polyamide solution, stir well, add coupling agent solution, stir well, and obtain lubricant.

[0074] Step 2: Preparation of modified glass fiber, including the following steps:

[0075] S1: Preparation of amino-branched polyamide:

[0076] Take 103g of diethylenetriamine, heat it at 55℃ for 3h, add 80g of succinic anhydride, raise the temperature to 140℃ and continue heating and stirring for 4h, cool it to obtain amino-branched polyamide;

[0077] S2: Plasma treatment:

[0078] Take glass fiber, cut it into 3-20mm fibers, rinse the surface twice with deionized water and acetone alternately, and dry it to obtain cleaned glass fiber; put the cleaned glass fiber into a low-temperature plasma reactor, fill it with argon gas at a pressure of 0.1MPa, and discharge it at a power of 80W for 4min to obtain plasma-treated glass fiber.

[0079] S3: Modification treatment:

[0080] Take 20g of tetraethyl orthosilicate and 100mL of ethanol, stir well, and add sodium hydroxide solution to adjust the pH value to 11 to obtain a tetraethyl orthosilicate solution; immerse the plasma-treated glass fiber in the tetraethyl orthosilicate solution, react for 4h, take it out and dry it to obtain glass fiber A.

[0081] Take 2g of amino-branched polyamide, 80mL of deionized water, and 20mL of ethanol, stir well, add 1g of glass fiber A, heat to 62℃, react for 20min, filter and dry to obtain glass fiber B;

[0082] Glass fiber B was immersed in a lubricant, then removed and dried to obtain modified glass fiber.

[0083] Comparative Example 1: No low-temperature plasma treatment was performed on the glass fiber surface; all other aspects were the same as in Example 1.

[0084] Step 1: Preparation of Lubricant

[0085] Take 6g of fatty alcohol polyoxyethylene ether, 3g of polyvinylpyrrolidone, 1g of triethanolamine borate, 2g of paraffin, and 100mL of deionized water, stir well to obtain a composite solution.

[0086] The composite solution contains the following components by weight fraction: 7 parts fatty alcohol polyoxyethylene ether, 4 parts polyvinylpyrrolidone, 1.5 parts triethanolamine borate, 2.3 parts paraffin, and 102 parts deionized water;

[0087] Take 12g of aqueous polyamide and 100mL of deionized water, stir well to obtain a polyamide solution;

[0088] The mass ratio of waterborne polyamide to deionized water is 12:100;

[0089] Take 5g of coupling agent Y-9669 and 3g of coupling agent A-187, add 50mL of deionized water, stir well, add pH adjuster to make the pH of the aqueous solution 6, stir well to obtain coupling agent solution;

[0090] The pH adjuster is citric acid;

[0091] Take 25g of waterborne polyurethane emulsion, add 100mL of deionized water, stir well, add composite solution and polyamide solution, stir well, add coupling agent solution, stir well, and obtain lubricant.

[0092] Step 2: Preparation of modified glass fiber, including the following steps:

[0093] S1: Preparation of amino-branched polyamide:

[0094] Take 103g of diethylenetriamine, heat it at 52℃ for 2.5h, add 80g of succinic anhydride, raise the temperature to 140℃ and continue heating and stirring for 3.5h, cool, and obtain amino-branched polyamide;

[0095] S2: Cleaning:

[0096] Take glass fiber, cut it into 3-20mm fibers, rinse the surface twice with deionized water and acetone alternately, and dry it to obtain cleaned glass fiber;

[0097] S3: Modification treatment:

[0098] Take 20g of tetraethyl orthosilicate and 100mL of ethanol, stir well, and add sodium hydroxide solution to adjust the pH to 11 to obtain a tetraethyl orthosilicate solution; immerse the cleaned glass fiber in the tetraethyl orthosilicate solution and react for 3.5h, then remove and dry to obtain glass fiber A;

[0099] Take 2g of amino-branched polyamide, 80mL of deionized water, and 20mL of ethanol, stir well, add 1g of glass fiber A, heat to 61℃, react for 18min, filter and dry to obtain glass fiber B.

[0100] Glass fiber B was immersed in a lubricant, then removed and dried to obtain modified glass fiber.

[0101] Comparative Example 2: No tetraethyl orthosilicate added, otherwise the same as in Example 1:

[0102] Step 1: Preparation of Lubricant

[0103] Take 6g of fatty alcohol polyoxyethylene ether, 3g of polyvinylpyrrolidone, 1g of triethanolamine borate, 2g of paraffin, and 100mL of deionized water, stir well to obtain a composite solution.

[0104] The composite solution contains the following components by weight fraction: 7 parts fatty alcohol polyoxyethylene ether, 4 parts polyvinylpyrrolidone, 1.5 parts triethanolamine borate, 2.3 parts paraffin, and 102 parts deionized water;

[0105] Take 12g of aqueous polyamide and 100mL of deionized water, stir well to obtain a polyamide solution;

[0106] The mass ratio of waterborne polyamide to deionized water is 12:100;

[0107] Take 5g of coupling agent Y-9669 and 3g of coupling agent A-187, add 50mL of deionized water, stir well, add pH adjuster to make the pH of the aqueous solution 6, stir well to obtain coupling agent solution;

[0108] The pH adjuster is citric acid;

[0109] Take 25g of waterborne polyurethane emulsion, add 100mL of deionized water, stir well, add composite solution and polyamide solution, stir well, add coupling agent solution, stir well, and obtain lubricant.

[0110] Step 2: Preparation of modified glass fiber, including the following steps:

[0111] S1: Preparation of amino-branched polyamide:

[0112] Take 103g of diethylenetriamine, heat it at 52℃ for 2.5h, add 80g of succinic anhydride, raise the temperature to 140℃ and continue heating and stirring for 3.5h, cool, and obtain amino-branched polyamide;

[0113] S2: Plasma treatment:

[0114] Take glass fiber, cut it into 3-20mm fibers, rinse the surface twice with deionized water and acetone alternately, and dry it to obtain cleaned glass fiber; put the cleaned glass fiber into a low-temperature plasma reactor, fill it with argon gas at a pressure of 0.1MPa, and discharge it at a power of 80W for 3min to obtain plasma-treated glass fiber.

[0115] S3: Modification treatment:

[0116] Take 2g of amino-branched polyamide, 80mL of deionized water, and 20mL of ethanol, stir well, add 1g of plasma-treated glass fiber, heat to 61℃, react for 18min, filter and dry to obtain glass fiber B.

[0117] Glass fiber B was immersed in a lubricant, then removed and dried to obtain modified glass fiber.

[0118] Comparative Example 3: No surface modification treatment of glass fiber was performed using amino-branched polyamide; all other aspects were the same as in Example 1.

[0119] Step 1: Preparation of Lubricant

[0120] Take 6g of fatty alcohol polyoxyethylene ether, 3g of polyvinylpyrrolidone, 1g of triethanolamine borate, 2g of paraffin, and 100mL of deionized water, stir well to obtain a composite solution;

[0121] The composite solution contains the following components by weight fraction: 7 parts fatty alcohol polyoxyethylene ether, 4 parts polyvinylpyrrolidone, 1.5 parts triethanolamine borate, 2.3 parts paraffin, and 102 parts deionized water;

[0122] Take 12g of aqueous polyamide and 100mL of deionized water, stir well to obtain a polyamide solution;

[0123] The mass ratio of waterborne polyamide to deionized water is 12:100;

[0124] Take 5g of coupling agent Y-9669 and 3g of coupling agent A-187, add 50mL of deionized water, stir well, add pH adjuster to make the pH of the aqueous solution 6, stir well to obtain coupling agent solution;

[0125] The pH adjuster is citric acid;

[0126] Take 25g of waterborne polyurethane emulsion, add 100mL of deionized water, stir well, add composite solution and polyamide solution, stir well, add coupling agent solution, stir well, and obtain lubricant.

[0127] Step 2: Preparation of modified glass fiber, including the following steps:

[0128] S1: Plasma treatment:

[0129] Take glass fiber, cut it into 3-20mm fibers, rinse the surface twice with deionized water and acetone alternately, and dry it to obtain cleaned glass fiber; put the cleaned glass fiber into a low-temperature plasma reactor, fill it with argon gas at a pressure of 0.1MPa, and discharge it at a power of 80W for 3min to obtain plasma-treated glass fiber.

[0130] S2: Modification treatment:

[0131] Take 20g of tetraethyl orthosilicate and 100mL of ethanol, stir well, and add sodium hydroxide solution to adjust the pH to 11 to obtain a tetraethyl orthosilicate solution; immerse the plasma-treated glass fiber in the tetraethyl orthosilicate solution and react for 3.5h, then remove and dry to obtain glass fiber A;

[0132] Glass fiber A was immersed in a lubricant, then removed and dried to obtain modified glass fiber.

[0133] Preparation of epoxy pultruded sheets:

[0134] Modified glass fibers prepared in Examples 1-3 and Comparative Examples 1-3 were used respectively. 65 wt% glass fiber and 35 wt% polyamide resin were used to press the fibers into sheets by hot press rollers. The sheets were then subjected to 0° and 90° transverse and longitudinal molding to obtain epoxy pultruded sheets.

[0135] experiment:

[0136] The epoxy pultruded sheets prepared in Examples 1-3 and Comparative Examples 1-3 were tested for flexural strength according to ASTM D790. The data are shown in the table below:

[0137] Lubricant immersion state Bending strength / MPa Example 1 good 283 Example 2 good 280 Example 3 good 285 Comparative Example 1 good 276 Comparative Example 2 good 261 Comparative Example 3 good 258

[0138] Conclusion: The data comparison in the table shows that Comparative Example 1, without low-temperature plasma treatment of the glass fiber surface, has a smaller surface area, resulting in less surface-loaded silica and amino-branched polyamide. This reduces the compatibility between the modified glass fiber and the lubricant, and also reduces the compatibility between the glass fiber and the polyamide resin, leading to a decrease in the mechanical properties of the epoxy pultruded sheet. Comparative Example 2, without adding tetraethyl orthosilicate, failed to form nano-silica on the glass fiber surface, resulting in decreased surface roughness and acid / alkali resistance, further reducing the mechanical properties of the epoxy pultruded sheet. Comparative Example 3, without using amino-branched polyamide for surface modification of the glass fiber, resulted in decreased compatibility between the glass fiber and the polyamide resin, leading to a decrease in the mechanical properties of the epoxy pultruded sheet. Examples 1-3 of this invention first subject the glass fiber surface to low-temperature plasma treatment, making the glass fiber surface slightly rougher and increasing the surface area; then, by adding tetraethyl orthosilicate to form nano-silica on the glass fiber surface, its surface roughness and acid / alkali resistance are further increased. Finally, the glass fiber was surface-modified using amino-branched polyamide, which improved the compatibility between the modified glass fiber and the lubricant. Simultaneously, amino groups were loaded onto the glass fiber, forming chemical bonds with the polyamide resin of the pultruded substrate, further enhancing the compatibility between the glass fiber and the polyamide resin, thereby improving the mechanical properties of the epoxy pultruded sheet. This invention prepares a lubricant and a lubricant-based modified glass fiber. Fatty alcohol polyoxyethylene ether, polyvinylpyrrolidone, triethanolamine borate, and paraffin wax are used to enhance lubrication performance. The addition of an aqueous polyurethane emulsion forms a continuous and tough protective film, significantly improving the wear resistance and mechanical damage resistance of the glass fiber. At this point, the lubricant penetration into the glass fiber is good, meeting industrial application standards.

[0139] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within the present invention.

Claims

1. A method for preparing lubricant-based modified glass fiber, characterized in that: Includes the following steps: S1: Take water-based polyurethane emulsion, add deionized water, stir evenly, add composite solution and polyamide solution, stir evenly, add coupling agent solution, stir evenly, and obtain lubricant; S2: Take tetraethyl orthosilicate and ethanol, stir evenly, add sodium hydroxide solution to adjust the pH value to obtain tetraethyl orthosilicate solution; immerse the plasma-treated glass fiber in tetraethyl orthosilicate solution, react for 3-4 hours, take it out and dry it to obtain glass fiber A; S3: Take amino-branched polyamide, deionized water and ethanol, stir evenly, add glass fiber A, heat to 60-62℃, react for 15-20 min, filter and dry to obtain glass fiber B; S4: Immerse glass fiber B in lubricant, remove and dry to obtain modified glass fiber; In S1, the lubricant is prepared by the following steps: Step 1: Take fatty alcohol polyoxyethylene ether, polyvinylpyrrolidone, triethanolamine borate, paraffin, and deionized water, stir evenly to obtain a composite solution; Step 2: Take water-based polyamide and deionized water, stir well to obtain a polyamide solution; Step 3: Take the coupling agent, add deionized water, stir well, add pH adjuster until the pH of the aqueous solution is 5-7, stir well, and obtain the coupling agent solution; Step 4: Take the water-based polyurethane emulsion, add deionized water, stir evenly, add the composite solution and polyamide solution, stir evenly, add the coupling agent solution, stir evenly, and obtain the lubricant.

2. The method for preparing lubricant-based modified glass fiber according to claim 1, characterized in that: The composite solution contains the following components, by weight fraction: 6-8 parts fatty alcohol polyoxyethylene ether, 3-5 parts polyvinylpyrrolidone, 1-2 parts triethanolamine borate, 2-2.5 parts paraffin, and 100-105 parts deionized water.

3. The method for preparing lubricant-based modified glass fiber according to claim 1, characterized in that: The mass ratio of the aqueous polyamide to deionized water is (10-15):

100.

4. The method for preparing lubricant-based modified glass fiber according to claim 1, characterized in that: The pH adjuster is any one or more of acetic acid, citric acid, and succinic acid.

5. The method for preparing lubricant-based modified glass fiber according to claim 1, characterized in that: The coupling agents are coupling agent Y-9669 and coupling agent A-187.

6. The method for preparing lubricant-based modified glass fiber according to claim 1, characterized in that: The method for preparing the plasma-treated glass fiber is as follows: take glass fiber, rinse the surface alternately with deionized water and acetone, and dry it to obtain cleaned glass fiber; put the cleaned glass fiber into a low-temperature plasma reactor, fill it with argon gas, and discharge it at a power of 80-85W for 3-4 minutes to obtain plasma-treated glass fiber.

7. The method for preparing lubricant-based modified glass fiber according to claim 1, characterized in that: The preparation method of the amino-branched polyamide is as follows: take diethylenetriamine, heat it at 50-55℃ for 2-3 hours, add succinic anhydride, raise the temperature to 140℃ and continue heating and stirring for 3-4 hours, cool, and obtain amino-branched polyamide.

8. Modified glass fiber prepared by the method for preparing lubricant-based modified glass fiber according to any one of claims 1-7.

9. The application of the modified glass fiber as described in claim 8 in epoxy pultruded sheets.