Impact-resistant fiber-reinforced synthetic resin composite material as well as preparation process and application thereof

Abstract

The invention belongs to the technical field of fiber-reinforced resin composite materials, and particularly provides an impact-resistant fiber-reinforced synthetic resin composite material, a preparation process and application of the impact-resistant fiber-reinforced synthetic resin composite material. The invention relates to a preparation process of an impact-resistant fiber-reinforced synthetic resin composite material. The preparation process comprises the following steps: 1) treating glass fibers with a presoaking solution to obtain modified glass fibers; and 2) mixing the modified glass fiber, epoxy resin and an auxiliary agent, degassing, pouring into a mold, curing to obtain the impact-resistant fiber-reinforced synthetic resin composite material, and adding interface reinforced particles which take ethylidene norbornene as a core and polyamide and zinc oxide as a shell in the preparation process of the prepreg liquid. The impact-resistant fiber-reinforced synthetic resin composite material prepared by the invention has good mechanical properties.

Description

Technical Field

[0001] The present application belongs to the technical field of fiber-reinforced resin composite materials, and in particular relates to an impact-resistant fiber-reinforced synthetic resin composite material, a preparation process, and applications thereof. Background Art

[0002] Fiber-reinforced resin composites are high-performance materials made by a specific preparation process, with high-performance fibers (such as carbon fibers, glass fibers, etc.) as the reinforcing phase and a resin matrix (such as epoxy resin, phenolic resin, etc.) as the continuous phase. They have shown high application value in multiple manufacturing fields, and the optimization of their preparation process and the improvement of their performance have always been the focus of research. In the aerospace sector, this material is often used in key components such as the fuselages and wings of civil airliners, as well as satellite main structures and rocket bodies. In the automotive sector, fiber-reinforced resin composites have also seen significant success. New energy vehicles use them in battery pack casings and body frames, reducing weight to extend range while providing reliable battery protection. Traditional fuel-powered vehicles use them in engine compartment components and chassis structures to improve power performance and fatigue resistance while reducing noise and vibration.

[0003] However, fiber-reinforced resin composites still have mechanical performance shortcomings in the above-mentioned application fields due to poor interfacial bonding between fibers and resins. The fiber-resin interface is a key channel for stress transmission. If the interface bonding is not tight, interfacial debonding is likely to occur when subjected to tensile loads, resulting in the material's tensile strength failing to meet design expectations. When subjected to impact loads, microcracks are likely to form at the interface and expand rapidly, causing the material's impact resistance to decline, making it difficult to meet the aerospace components' tolerance requirements for extreme impact environments and the automotive components' requirements for collision safety. At the same time, interfacial bonding defects will also affect the material's toughness, causing the material to easily fracture brittlely during stress, limiting its application in aerospace structural parts and automotive load-bearing components that have high requirements for material toughness. Therefore, improving the interfacial bonding between fibers and resins has become a key direction for improving the mechanical properties of fiber-reinforced resin composites and expanding their scope of application. The patent application document with application publication number CN114891320A discloses an epoxy resin / chopped glass fiber composite material and its preparation method. The preparation method of the composite material of this application is to mix epoxy resin monomer, acid curing agent and chopped glass fiber, and prepare the composite material through dynamic vulcanization reaction. The acid curing agent used is a dicarboxylic acid with a disulfide bond, which makes the composite material have a certain high-temperature fluidity, and the glass fiber can be dispersed more evenly in the reaction system, thereby improving the mechanical properties of the composite material. However, this application only promotes the uniform dispersion of glass fiber in the composite material by adjusting the fluidity of the composite material, which has no obvious promoting effect on the bonding performance of glass fiber and resin. When the composite material is impacted by external force, the bonding between the glass fiber and the resin may cause a gap between the two due to the weak interaction force, which hinders the dispersion of stress, further expands the gap, and affects the normal use of the composite material. Summary of the Invention

[0004] In order to solve the above problems and further improve the bonding strength between the fiber and the resin matrix, and thus enhance the mechanical properties of the fiber-reinforced resin composite material, the present application provides an impact-resistant fiber-reinforced synthetic resin composite material, a preparation process and its application.

[0005] In a first aspect, the present application provides a process for preparing an impact-resistant fiber-reinforced synthetic resin composite material, comprising the following steps: 1) The glass fiber is immersed in a prepreg solution for impregnation, and then filtered and dried to obtain the modified glass fiber; 2) Mixing the modified glass fiber and epoxy resin, adding an additive, mixing evenly, degassing the resulting mixture, and then pouring the mixture into a mold and curing it to obtain an impact-resistant fiber-reinforced synthetic resin composite material; The prepreg is made of raw materials including tetraethoxysilane, polyvinyl pyrrolidone, silane coupling agent and interface strengthening particles; The interface enhancement particles are prepared by taking ethylidene norbornene as the core and polyamide and zinc oxide as the shell.

[0006] Furthermore, the preparation method of the pre-soak comprises the following steps: S1: Tetraethoxysilane is dissolved in ethanol, and then a mixed solution of a silane coupling agent and ethanol is added while continuously stirring, and the mixture is allowed to stand to obtain a precursor solution; S2: Mix polyvinyl pyrrolidone and deionized water, then drop the precursor solution into it, stir evenly, add interface reinforcement particles, and perform ultrasonic treatment to obtain a pre-impregnation solution.

[0007] Furthermore, the preparation method of the interface-enhanced particles includes the following steps: uniformly mixing ethylidene norbornene, an emulsifier, and deionized water to obtain an emulsion; dropwise adding a polyamide prepolymer into the emulsion, reacting for a period of time, then adding zinc oxide and continuing the reaction; after the reaction is completed, adding the obtained solid product into a polyamide prepolymer solution, mixing evenly, standing, filtering, washing, and then soaking in a methanol-water solution, filtering, washing, and drying to obtain interface-enhanced particles.

[0008] Furthermore, the zinc oxide is produced by reacting zinc salt and sodium hydroxide in a mixed alcohol environment.

[0009] Furthermore, the polyamide prepolymer is prepared by mixing hexamethylenediamine and polyether ester acid.

[0010] Furthermore, the polyether ester acid is prepared by reacting polyether polyol and adipic acid.

[0011] Furthermore, the molar ratio of the polyether polyol to adipic acid is 1:(2-4).

[0012] Furthermore, the mixed alcohol is prepared by mixing ethanol and polyethylene glycol in a mass ratio of (2-5):1.

[0013] In a second aspect, the present application provides an impact-resistant fiber-reinforced synthetic resin composite material, which is prepared using the above-mentioned preparation process.

[0014] In a third aspect, the present application provides an application of an impact-resistant fiber-reinforced synthetic resin composite material in the aerospace and automotive fields.

[0015] Compared with the prior art, this application has the following beneficial effects: 1. When the composite material is subjected to a strong external impact, the shell of the interface reinforcement particles breaks, and the ethylidene norbornene in the core layer is released, filling the microcracks of the composite material and then solidifying, thereby repairing the composite material and preventing the cracks from further expanding.

[0016] 2. The interface reinforcement particles are attached to the surface of the glass fiber, increasing the specific surface area of ​​the glass fiber. The needle-shaped protrusion structure on the surface of the interface reinforcement particles can form a good interlocking effect with the resin. This structure can increase the bonding force between the glass fiber and the resin, effectively avoid the formation of gaps at the interface between the glass fiber and the resin, reduce the phenomenon of glass fiber debonding after the composite material is subjected to force, and improve the impact resistance of the composite material.

[0017] 3. After swelling, the outer shell of the interface reinforcement particles participates in the curing process of the epoxy resin during the curing process of the composite material, forming a more flexible epoxy resin at the junction of the two. This is because the polyether ester acid molecular chain also contains flexible and easily rotatable ether bonds, which greatly improves the flexibility of the epoxy resin and improves the mechanical properties of its cured product. This more flexible epoxy resin layer at the junction of the glass fiber and the resin matrix effectively buffers external forces, thereby improving the mechanical properties of the composite material. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 Scanning electron microscope images of the interface enhancement particles prepared in Examples 1-3 of the present application. DETAILED DESCRIPTION

[0019] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0020] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this application pertains. The terms used herein in the specification of this application are for the purpose of describing specific embodiments only and are not intended to limit this application. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0021] Where “including,” “having,” and “comprising” are used herein, it is intended to cover a non-exclusive inclusion, and another component may also be added unless a clear limiting term such as “only,” “consisting of,” etc. is used.

[0022] The words "preferably", "more preferably", "preferably", "better", etc. in this application refer to embodiments of the present application that may provide certain beneficial effects in certain circumstances. However, other embodiments may also be preferred under the same circumstances or other circumstances. In addition, the statement of one or more preferred embodiments does not imply that other embodiments are not available, nor is it intended to exclude other embodiments from the scope of this application. That is, in this application, "preferably", "more preferably", "preferably", "better", etc. are merely descriptions of implementation methods or examples with better effects, but do not constitute a limitation on the scope of protection of this application.

[0023] In the present application, “further”, “further”, “particularly”, etc. are used for descriptive purposes to indicate differences in content but should not be understood as limiting the scope of protection of the present application.

[0024] In this application, "at least one" means more than one, such as one, two, or more than two. "Multiple" or "several" means at least two, such as two, three, etc., and "multi-layer" means at least two layers, such as two, three, etc., unless otherwise specifically defined. In the description of this application, "several" means at least one, such as one, two, etc., unless otherwise specifically defined.

[0025] When a numerical range is disclosed herein, the range is considered continuous and includes the minimum and maximum values ​​of the range, as well as every value between such minimum and maximum values. Further, when a range refers to an integer, every integer between the minimum and maximum values ​​of the range is included. In addition, when multiple ranges are provided to describe a feature or characteristic, the ranges can be combined. In other words, unless otherwise indicated, all ranges disclosed herein are understood to include any and all subranges subsumed therein.

[0026] Unless otherwise specified, all steps of the present application may be performed sequentially or randomly. For example, the method includes steps (a) and (b), indicating that the method may include steps (a) and (b) performed sequentially, or may include steps (b) and (a) performed sequentially. For example, the method may further include step (c), indicating that step (c) may be added to the method in any order, for example, the method may include steps (a), (b) and (c), or may include steps (a), (c) and (b), or may include steps (c), (a) and (b), etc. Unless otherwise mentioned, terms in the singular may include plural forms and are not to be understood as being one in number.

[0027] In this application, “above” or “below” includes the number itself. For example, “1 below” includes 1.

[0028] In the present application, room temperature refers to 0-40°C, including but not limited to 10-40°C, or further 20-30°C.

[0029] After extensive experimental research, this application provides a preparation process for an impact-resistant fiber-reinforced synthetic resin composite material, comprising the following steps: 1) The glass fiber is immersed in a prepreg solution for impregnation, and then filtered and dried to obtain the modified glass fiber; 2) Mixing the modified glass fiber and epoxy resin, adding an additive, mixing evenly, degassing the resulting mixture, and then pouring the mixture into a mold and curing it to obtain an impact-resistant fiber-reinforced synthetic resin composite material; The prepreg is made of raw materials including tetraethoxysilane, polyvinyl pyrrolidone, silane coupling agent and interface strengthening particles; The interface enhancement particles are prepared by taking ethylidene norbornene as the core and polyamide and zinc oxide as the shell.

[0030] In some embodiments of the present application, the method for preparing the pre-dip comprises the following steps: S1: Tetraethoxysilane is dissolved in ethanol, and then a mixed solution of a silane coupling agent and ethanol is added while continuously stirring, and the mixture is allowed to stand to obtain a precursor solution; S2: Mix polyvinyl pyrrolidone and deionized water, then drop the precursor solution into it, stir evenly, add interface reinforcement particles, and perform ultrasonic treatment to obtain a pre-impregnation solution.

[0031] In some embodiments of the present application, the preparation method of the interface-enhanced particles includes the following steps: uniformly mixing ethylidene norbornene, an emulsifier, and deionized water to obtain an emulsion; dropping a polyamide prepolymer into the emulsion, reacting for a period of time, and then adding zinc oxide to continue the reaction. After the reaction is completed, the obtained solid product is added to a polyamide prepolymer solution, mixed evenly, allowed to stand, filtered, washed, and then immersed in a methanol aqueous solution, filtered, washed, and dried to obtain interface-enhanced particles.

[0032] In some embodiments of the present application, the method for preparing zinc oxide comprises the following steps: mixing ethanol and polyethylene glycol, adding zinc salt and sodium hydroxide, adjusting the temperature to 110-130°C, reacting for 8-15 hours, and after the reaction is completed, filtering, washing, and drying to obtain zinc oxide.

[0033] In some embodiments of the present application, the method for preparing the polyamide prepolymer comprises the following steps: mixing hexamethylenediamine and polyether ester acid, controlling the reaction temperature to 70-90° C., and reacting for 1-2 hours to obtain the polyamide prepolymer.

[0034] In some embodiments of the present application, the preparation method of the polyether ester acid includes the following steps: polyether polyol and adipic acid are put into a reaction container in sequence, then toluene is added, reacted at 110-130°C for a period of time, distilled under reduced pressure, then heated to 170-180°C for 2-3 hours, and rotary evaporated to obtain polyether ester acid.

[0035] In some embodiments of the present application, the molar ratio of the polyether polyol to adipic acid is 1:(2-4).

[0036] In some specific embodiments of the present application, the molar ratio of polyether polyol to adipic acid can be 1:(2-2.5), 1:(2.5-3), 1:(3-3.5), 1:(3.5-4); typically but not limiting, for example, it can be 1:2.5, 1:3, 1:3.2.

[0037] In some embodiments of the present application, the mixed alcohol is prepared by mixing ethanol and polyethylene glycol in a mass ratio of (2-5):1.

[0038] In some specific embodiments of the present application, the mass ratio of ethanol to polyethylene glycol can be (2-2.5):1, (2.5-3):1, (3-3.5):1, (3.5-4):1, (4-4.5):1, (4.5-5):1; typically but not limitatively, for example, it can be 2.5:1, 2.8:1.

[0039] The present application is further described below by way of examples, but the scope of the present application is not limited thereby.

[0040] When the embodiments provide numerical ranges, it should be understood that, unless otherwise specified herein, both endpoints of each numerical range and any numerical value between the two endpoints may be selected. Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as those generally understood by those skilled in the art. Where specific conditions are not specified in the embodiments, they are carried out according to conventional conditions or the conditions recommended by the manufacturer. Where all reagents or instruments are not specified by the manufacturer, they are conventional products that can be purchased commercially. In addition to the specific methods, equipment, and materials used in the embodiments, according to the prior art mastery and the record of the present application by those skilled in the art, any methods, equipment, and materials of the prior art similar or equivalent to the methods, equipment, and materials described in the embodiments of the present application can also be used to realize the present application.

[0041] The average length of the glass fibers used in this embodiment and the comparative example is 2-3 mm.

[0042] Example 1 The preparation process of the impact-resistant fiber-reinforced synthetic resin of this embodiment is as follows: 1) Weigh 100 g of ethanol into a 500 mL three-necked flask, then add 15 g of tetraethoxysilane. Stir at 300 rpm for 40 min. Then, add a mixed solution consisting of 2.5 g of aminopropyltrimethoxysilane and 95 g of ethanol at a rate of 2.8 mL / min. After the addition of the mixed solution, let it stand for 15 h to obtain a precursor solution. 2) 30g of deionized water was placed in a 500mL beaker, followed by 0.8g of polyvinylpyrrolidone K90. The mixture was stirred magnetically until the polyvinylpyrrolidone K90 was completely dissolved. The precursor solution was then added at a rate of 1.2mL / min. After the precursor solution was added, 10g of interface reinforcement particles were added and ultrasonically dispersed for 20min to obtain a prepreg solution. 3) 30 g of glass fiber was ultrasonically cleaned in 100 g of acetone for 2 h, then dried in a drying oven. The dried glass fiber was placed in a 250 mL beaker containing 70 g of pre-impregnation solution and immersed for 15 min. The pre-impregnation solution was filtered and dried to obtain the modified glass fiber. 4) Weigh 25 g of modified glass fiber, 90 g of epoxy resin E51, and 10 g of neopentyl glycol diglycidyl ether into a 250 mL beaker and stir for 2 h. Then, add 5 g of triethylenetetramine and 0.02 g of Grubbs first-generation catalyst and mix thoroughly. Transfer the mixture to an oven for vacuum degassing for 30 min. Then, cast the mixture into a polytetrafluoroethylene mold and cure at 80°C for 1 h. Then, increase the temperature to 150°C and continue curing for 3 h to obtain an impact-resistant fiber-reinforced synthetic resin composite material.

[0043] The preparation method of the interface enhancement particles of this embodiment is as follows: M1: 100 g of ethanol and 40 g of polyethylene glycol were added to a reactor and stirred for 10 min. Then, 5 g of zinc acetate and 15.3 g of sodium hydroxide were added. The temperature was adjusted to 110°C and the reaction was carried out for 15 h. After the reaction was completed, the mixture was filtered, washed, and dried to obtain zinc oxide. M2: 8 g of polyethylene glycol (PEG-200) and 14.6 g of adipic acid were placed in a 250 mL three-necked flask, followed by the addition of 120 g of toluene. The mixture was reacted at 130°C for 1 h. After the reaction, vacuum distillation was performed. The reaction system was then heated to 170°C and the reaction was continued for 3 h. The mixture was then rotary evaporated to obtain polyether ester acid. M3: Weigh 11.5 g of hexamethylenediamine, 23 g of polyether ester acid, and 100 g of deionized water into a 100 mL three-necked flask and mix well. Then, add 0.2 g of triethanolamine. Adjust the temperature to 70°C, react for 1 h, and rotary evaporate to obtain a polyamide prepolymer. M4: 5 g of ethylidene norbornene, 0.2 g of sodium dodecylbenzenesulfonate and 60 g of deionized water were mixed and stirred at 400 rpm for 40 min to obtain an emulsion; 18 g of polyamide prepolymer was added dropwise to the emulsion at a rate of 0.5 mL / min, and the mixture was reacted for 35 min after the addition was completed. 1.5 g of zinc oxide was then added and the reaction was continued for 3 h. After the reaction was completed, the obtained solid product was added to a mixed solution consisting of 10 g of polyamide prepolymer and 30 g of deionized water, ultrasonically dispersed for 10 min, adjusted the temperature to 55°C and allowed to stand for 1 h, filtered, washed, and then immersed in a methanol aqueous solution with a mass percentage concentration of 65% for 5 min, filtered, washed, and dried to obtain interface-reinforced particles.

[0044] Example 2 The preparation process of the impact-resistant fiber-reinforced synthetic resin of this embodiment is as follows: 1) Weigh 100 g of ethanol into a 500 mL three-necked flask, then add 15 g of tetraethoxysilane. Stir at 300 rpm for 40 min. Then, add a mixed solution consisting of 2.5 g of aminopropyltrimethoxysilane and 95 g of ethanol at a rate of 2.5 mL / min. After the addition of the mixed solution, let it stand for 15 h to obtain a precursor solution. 2) 30g of deionized water was placed in a 500mL beaker, followed by 0.8g of polyvinylpyrrolidone K90. The mixture was stirred magnetically until the polyvinylpyrrolidone K90 was completely dissolved. The precursor solution was then added at a rate of 1.2mL / min. After the precursor solution was added, 7g of interface reinforcement particles were added and ultrasonically dispersed for 20min to obtain a prepreg solution. 3) 30 g of glass fiber was ultrasonically cleaned in 100 g of acetone for 2 h, then dried in a drying oven. The dried glass fiber was placed in a 250 mL beaker containing 70 g of pre-impregnation solution and immersed for 15 min. The pre-impregnation solution was filtered and dried to obtain the modified glass fiber. 40 g of modified glass fiber, 140 g of epoxy resin E51, and 15 g of neopentyl glycol diglycidyl ether were weighed and placed in a 250 mL beaker and stirred for 2 h. Subsequently, 7 g of triethylenetetramine and 0.02 g of Grubbs first-generation catalyst were added and mixed evenly. The mixture was transferred to an oven for vacuum degassing for 40 min. The mixture was then poured into a polytetrafluoroethylene mold and cured at 80°C for 1 h. The temperature was then increased to 150°C and cured for another 3 h to obtain an impact-resistant fiber-reinforced synthetic resin composite material.

[0045] The preparation method of the interface enhancement particles of this embodiment is as follows: M1: 112 g of ethanol and 40 g of polyethylene glycol were added to a reactor and stirred for 10 min. Then, 5.5 g of zinc acetate and 15.7 g of sodium hydroxide were added. The temperature was adjusted to 130°C and the reaction was carried out for 8 h. After the reaction was completed, the mixture was filtered, washed, and dried to obtain zinc oxide. M2: 8 g of polyethylene glycol (PEG-200) and 17.5 g of adipic acid were placed in a 250 mL three-necked flask, followed by the addition of 120 g of toluene. The mixture was reacted at 110°C for 2 h. After the reaction was complete, vacuum distillation was performed. The reaction system was then heated to 180°C and the reaction was continued for 2 h. The mixture was then rotary distilled to obtain polyether ester acid. M3: Weigh 11.5 g of hexamethylenediamine, 23 g of polyether ester acid, and 100 g of deionized water into a 100 mL three-necked flask and mix well. Then, add 0.2 g of triethanolamine. Adjust the temperature to 75°C, react for 1 h, and rotary evaporate to obtain a polyamide prepolymer. M4: 5 g of ethylidene norbornene, 0.2 g of sodium dodecylbenzenesulfonate and 60 g of deionized water were mixed and stirred at 400 rpm for 40 min to obtain an emulsion; 20 g of polyamide prepolymer was added dropwise to the emulsion at a rate of 0.5 mL / min, and the mixture was reacted for 35 min after the addition was completed. 1.5 g of zinc oxide was then added and the reaction was continued for 3 h. After the reaction was completed, the obtained solid product was added into a mixed solution consisting of 13 g of polyamide prepolymer and 30 g of deionized water, ultrasonically dispersed for 10 min, adjusted the temperature to 55°C and allowed to stand for 1 h, filtered, washed, and then immersed in a methanol aqueous solution with a mass percentage concentration of 65% for 5 min, filtered, washed, and dried to obtain interface-reinforced particles.

[0046] Example 3 The preparation process of the impact-resistant fiber-reinforced synthetic resin of this embodiment is as follows: 1) Weigh 100 g of ethanol into a 500 mL three-necked flask, then add 15 g of tetraethoxysilane. Stir at 300 rpm for 40 min. Then, add a mixed solution consisting of 2.5 g of aminopropyltrimethoxysilane and 95 g of ethanol at a rate of 2.8 mL / min. After the addition of the mixed solution, let it stand for 20 h to obtain a precursor solution. 2) 30g of deionized water was placed in a 500mL beaker, followed by 1.2g of polyvinylpyrrolidone K90. The mixture was stirred magnetically until the polyvinylpyrrolidone K90 was completely dissolved. The precursor solution was then added at a rate of 1.2mL / min. After the precursor solution was added, 10g of interface reinforcement particles were added and ultrasonically dispersed for 20min to obtain a prepreg solution. 3) 30 g of glass fiber was ultrasonically cleaned in 100 g of acetone for 2 h, then dried in a drying oven. The dried glass fiber was placed in a 250 mL beaker containing 70 g of pre-impregnation solution and immersed for 15 min. The pre-impregnation solution was filtered and dried to obtain the modified glass fiber. 4) Weigh 30 g of modified glass fiber, 120 g of epoxy resin E51, and 12 g of neopentyl glycol diglycidyl ether into a 250 mL beaker and stir for 2 h. Then, add 5.2 g of triethylenetetramine and 0.02 g of Grubbs first-generation catalyst and mix thoroughly. Transfer the mixture to an oven for vacuum degassing for 30 min. Then, cast the mixture into a polytetrafluoroethylene mold and cure at 80°C for 1 h. Then, increase the temperature to 150°C and continue curing for 3 h to obtain an impact-resistant fiber-reinforced synthetic resin composite material.

[0047] The preparation method of the interface enhancement particles of this embodiment is as follows: M1: 100 g of ethanol and 40 g of polyethylene glycol were added to a reactor and stirred for 10 min. Then, 5 g of zinc acetate and 15.3 g of sodium hydroxide were added. The temperature was adjusted to 115°C and the reaction was carried out for 13 h. After the reaction was completed, the mixture was filtered, washed, and dried to obtain zinc oxide. M2: 8 g of polyethylene glycol (PEG-200) and 18.6 g of adipic acid were placed in a 250 mL three-necked flask, followed by the addition of 120 g of toluene. The reaction was carried out at 100°C for 1.5 h. After the reaction was completed, vacuum distillation was performed. The reaction system was then heated to 175°C and the reaction was continued for 2.5 h. The mixture was then rotary evaporated to obtain polyether ester acid. M3: Weigh 11.5 g of hexamethylenediamine, 23 g of polyether ester acid, and 100 g of deionized water into a 100 mL three-necked flask and mix well. Then, add 0.2 g of triethanolamine. Adjust the temperature to 70°C, react for 1.5 h, and rotary evaporate to obtain a polyamide prepolymer. M4: 5 g of ethylidene norbornene, 0.2 g of sodium dodecylbenzenesulfonate and 60 g of deionized water were mixed and stirred at 400 rpm for 40 min to obtain an emulsion; 18 g of polyamide prepolymer was added dropwise to the emulsion at a rate of 0.5 mL / min, and the mixture was reacted for 30 min after the addition was completed. 1.5 g of zinc oxide was then added and the reaction was continued for 3 h. After the reaction was completed, the obtained solid product was added into a mixed solution consisting of 10 g of polyamide prepolymer and 30 g of deionized water, ultrasonically dispersed for 10 min, adjusted the temperature to 55°C and allowed to stand for 1 h, filtered, washed, and then immersed in a methanol aqueous solution with a mass percentage concentration of 65% for 5 min, filtered, washed, and dried to obtain interface-reinforced particles.

[0048] Comparative Example 1 The preparation process of the impact-resistant fiber-reinforced synthetic resin of this comparative example is as follows: 1) Weigh 100 g of ethanol into a 500 mL three-necked flask, then add 15 g of tetraethoxysilane. Stir at 300 rpm for 40 min. Then, add a mixed solution consisting of 2.5 g of aminopropyltrimethoxysilane and 95 g of ethanol at a rate of 2.8 mL / min. After the addition of the mixed solution, let it stand for 15 h to obtain a precursor solution. 2) 30g of deionized water was placed in a 500mL beaker, followed by 0.8g of polyvinylpyrrolidone K90. The mixture was stirred magnetically until the polyvinylpyrrolidone K90 was completely dissolved. The precursor solution was then added at a rate of 1.2mL / min. After the precursor solution was added, 10g of interface reinforcement particles were added and ultrasonically dispersed for 20min to obtain a prepreg solution. 3) 30 g of glass fiber was ultrasonically cleaned in 100 g of acetone for 2 h, then dried in a drying oven. The dried glass fiber was placed in a 250 mL beaker containing 70 g of pre-impregnation solution and immersed for 15 min. The pre-impregnation solution was filtered and dried to obtain the modified glass fiber. 4) Weigh 25 g of modified glass fiber, 90 g of epoxy resin E51, and 10 g of neopentyl glycol diglycidyl ether into a 250 mL beaker and stir for 2 h. Then, add 5 g of triethylenetetramine and 0.02 g of Grubbs first-generation catalyst and mix thoroughly. Transfer the mixture to an oven for vacuum degassing for 30 min. Then, cast the mixture into a polytetrafluoroethylene mold and cure at 80°C for 1 h. Then, increase the temperature to 150°C and continue curing for 3 h to obtain an impact-resistant fiber-reinforced synthetic resin composite material.

[0049] The preparation method of the interface enhancement particles of this comparative example is as follows: M1: 100 g of ethanol and 40 g of polyethylene glycol were added to a reactor and stirred for 10 min. Then, 5 g of zinc acetate and 15.3 g of sodium hydroxide were added. The temperature was adjusted to 110°C and the reaction was carried out for 15 h. After the reaction was completed, the mixture was filtered, washed, and dried to obtain zinc oxide. M2: 8 g of polyethylene glycol (PEG-200) and 14.6 g of adipic acid were placed in a 250 mL three-necked flask, followed by the addition of 120 g of toluene. The mixture was reacted at 130°C for 1 h. After the reaction, vacuum distillation was performed. The reaction system was then heated to 170°C and the reaction was continued for 3 h. The mixture was then rotary evaporated to obtain polyether ester acid. M3: Weigh 11.5 g of hexamethylenediamine, 23 g of polyether ester acid, and 100 g of deionized water into a 100 mL three-necked flask and mix well. Then, add 0.2 g of triethanolamine. Adjust the temperature to 70°C, react for 1 h, and rotary evaporate to obtain a polyamide prepolymer. M4: 5 g of ethylidene norbornene, 0.2 g of sodium dodecylbenzenesulfonate and 60 g of deionized water were mixed and stirred at 400 rpm for 40 min to obtain an emulsion; 18 g of polyamide prepolymer was added dropwise to the emulsion at a rate of 0.5 mL / min, and the mixture was reacted for 3 h. After the reaction, the obtained solid product was added to a mixed solution consisting of 10 g of polyamide prepolymer and 30 g of deionized water, and ultrasonically dispersed for 10 min. The temperature was adjusted to 55°C and allowed to stand for 1 h. The solid product was filtered, washed, and then immersed in a methanol aqueous solution with a mass percentage concentration of 65% for 5 min. The solid product was filtered, washed, and dried to obtain interface-reinforced particles.

[0050] Comparative Example 2 The preparation process of the impact-resistant fiber-reinforced synthetic resin of this comparative example is as follows: 1) Weigh 100 g of ethanol into a 500 mL three-necked flask, then add 15 g of tetraethoxysilane. Stir at 300 rpm for 40 min. Then, add a mixed solution consisting of 2.5 g of aminopropyltrimethoxysilane and 95 g of ethanol at a rate of 2.8 mL / min. After the addition of the mixed solution, let it stand for 15 h to obtain a precursor solution. 2) Place 30g of deionized water in a 500mL beaker, add 0.8g of polyvinylpyrrolidone K90, and stir magnetically until the polyvinylpyrrolidone K90 is completely dissolved. Then, add the precursor solution at a rate of 1.2mL / min. After the precursor solution is added, ultrasonically disperse for 20min to obtain a pre-dip solution. 3) 30 g of glass fiber was ultrasonically cleaned in 100 g of acetone for 2 h, then dried in a drying oven. The dried glass fiber was placed in a 250 mL beaker containing 70 g of pre-impregnation solution and immersed for 15 min. The pre-impregnation solution was filtered and dried to obtain the modified glass fiber. 4) Weigh 25 g of modified glass fiber, 90 g of epoxy resin E51, and 10 g of neopentyl glycol diglycidyl ether into a 250 mL beaker and stir for 2 h. Then, add 5 g of triethylenetetramine and mix thoroughly. Transfer the mixture to an oven for vacuum degassing for 30 min. Then, cast the mixture into a polytetrafluoroethylene mold and cure at 80°C for 1 h. Then, increase the temperature to 150°C and continue curing for 3 h to obtain an impact-resistant fiber-reinforced synthetic resin composite.

[0051] Performance testing 1. Bending test Referring to the GB / T1449-2005 standard, bending tests were conducted on impact-resistant fiber-reinforced synthetic resin composites using a universal mechanical testing machine at a test rate of 10 mm / min. The test specimens were sized at 40 mm × 15 mm × 2 mm. The test results are shown in Table 1.

[0052] 2. Impact test Impact tests were conducted on impact-resistant fiber-reinforced synthetic resin composites using a simply supported beam impact tester. The test method followed the standard GB / T2567-2021. The test specimen dimensions were 10 mm × 5 mm × 2 mm, and the test fixture span was 60 mm. The test results are shown in Table 1.

[0053] 3. Tensile test With reference to the standard GB / T2567-2021, tensile tests were conducted on impact-resistant fiber-reinforced synthetic resin composites using a universal mechanical testing machine at a test speed of 10 mm / min. The test results are shown in Table 1.

[0054] 4. The interface enhancement particles prepared in Examples 1-3 were observed using a scanning electron microscope. The images obtained are as follows: Figure 1 shown.

[0055] Table 1 Performance test data of impact-resistant fiber-reinforced synthetic resin composite materials of Examples 1-3 and Comparative Examples 1-2 Analysis of Examples 1-3 and Comparative Examples 1-2, combined with Table 1, shows that preparing interface-reinforced particles with polyamide and zinc oxide as shells and attaching these interface-reinforced particles to the surface of glass fibers has a good effect on improving the mechanical properties of the composite material. This is because the interface-reinforced particles effectively improve the bonding ability between the glass fiber and the resin. When the composite material is subjected to external force, the stress dispersion at the interface between the glass fiber and the resin is smoother and faster, thereby enhancing the mechanical properties of the composite material. The interface-reinforced particles prepared in Comparative Example 1 only have polyamide as the shell, and the specific surface area is reduced, thereby reducing the bonding ability between the glass fiber and the resin compared with the embodiment, which is intuitively manifested in that the mechanical properties of Comparative Example 1 are significantly reduced compared with the embodiment. No interface-reinforced particles are added in Comparative Example 2, which reduces the interfacial bonding ability between the glass fiber and the resin and the stress buffering and dispersion ability at the interface bonding point, thereby further reducing the mechanical properties of the composite material prepared in Comparative Example 2.

[0056] Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments, or make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application should be included in the scope of protection of the present application.

Claims

1. A process for preparing an impact-resistant fiber-reinforced synthetic resin composite material, characterized by: The steps include: 1) The glass fiber is immersed in a prepreg solution for impregnation, and then filtered and dried to obtain the modified glass fiber; 2) Mixing the modified glass fiber and epoxy resin, adding an additive, mixing evenly, degassing the resulting mixture, and then pouring the mixture into a mold and curing it to obtain an impact-resistant fiber-reinforced synthetic resin composite material; The prepreg is made of raw materials including tetraethoxysilane, polyvinyl pyrrolidone, silane coupling agent and interface strengthening particles; The interface enhancement particles are prepared by taking ethylidene norbornene as the core and polyamide and zinc oxide as the shell.

2. The process for preparing an impact-resistant fiber-reinforced synthetic resin composite material according to claim 1, characterized in that: The preparation method of the pre-soak comprises the following steps: S1: Tetraethoxysilane is dissolved in ethanol, and then a mixed solution of a silane coupling agent and ethanol is added while continuously stirring, and the mixture is allowed to stand to obtain a precursor solution; S2: Mix polyvinyl pyrrolidone and deionized water, then drop the precursor solution into it, stir evenly, add interface reinforcement particles, and perform ultrasonic treatment to obtain a pre-impregnation solution.

3. The process for preparing an impact-resistant fiber-reinforced synthetic resin composite material according to claim 1, characterized in that: The preparation method of the interface-enhanced particles comprises the following steps: uniformly mixing ethylidene norbornene, an emulsifier, and deionized water to obtain an emulsion; dropwise adding a polyamide prepolymer into the emulsion, reacting for a period of time, adding zinc oxide, and continuing the reaction; after the reaction is completed, adding the obtained solid product into a polyamide prepolymer solution, uniformly mixing, standing, filtering, washing, and then soaking in a methanol-water solution, filtering, washing, and drying to obtain the interface-enhanced particles.

4. The process for preparing an impact-resistant fiber-reinforced synthetic resin composite material according to claim 1, wherein: The zinc oxide is produced by the reaction of zinc salt and sodium hydroxide in a mixed alcohol environment.

5. The process for preparing an impact-resistant fiber-reinforced synthetic resin composite material according to claim 3, characterized in that: The polyamide prepolymer is prepared by mixing hexamethylenediamine and polyether ester acid.

6. The process for preparing an impact-resistant fiber-reinforced synthetic resin composite material according to claim 5, characterized in that: The polyether ester acid is prepared by reacting polyether polyol and adipic acid.

7. The process for preparing an impact-resistant fiber-reinforced synthetic resin composite material according to claim 6, characterized in that: The molar ratio of the polyether polyol to adipic acid is 1:(2-4).

8. The process for preparing an impact-resistant fiber-reinforced synthetic resin composite material according to claim 4, characterized in that: The mixed alcohol is prepared by mixing ethanol and polyethylene glycol in a mass ratio of (2-5):

1.

9. An impact-resistant fiber-reinforced synthetic resin composite material, characterized by: The method is prepared by the preparation process described in any one of claims 1 to 8.

10. An application of an impact-resistant fiber-reinforced synthetic resin composite material, characterized by: The impact-resistant fiber-reinforced synthetic resin composite material as claimed in claim 9 is used in the aerospace and automotive fields.

Images