Regeneration method of waste glass fiber composite material metering box

Abstract

The invention discloses a regeneration method of a waste glass fiber composite material metering box, and relates to the field of glass fiber composite materials, and the regeneration method comprises the following steps: S1, recycling the waste glass fiber composite material metering box; s2, the waste glass fiber composite material metering box is subjected to multi-stage crushing and screening, and powder is obtained; s3, weighing raw materials in parts by weight as follows: 10-70 parts of the powder, 5-25 parts of resin, 0.2-5 parts of a curing agent, 10-50 parts of glass fibers, 0-40 parts of a flame retardant, 0-15 parts of filler, 0-1 part of a dispersing agent, 1-5 parts of an activating agent and 0-5 parts of a catalyst, and uniformly mixing the raw materials to obtain a mixed material; s4, the mixed material is sequentially subjected to material distribution and hot-pressing curing, and the glass fiber composite material plate is obtained; and S5, manufacturing the glass fiber composite material plate into a new glass fiber composite material metering box. According to the invention, harmless treatment of the waste glass fiber composite material metering box can be realized, and resource regeneration is realized.

Description

Technical Field

[0001] This invention relates to the field of glass fiber composite materials, and more specifically to a method for regenerating waste glass fiber composite material metering boxes. Background Technology

[0002] In recent years, metering boxes made of glass fiber reinforced unsaturated polyester / epoxy resin thermosetting composite material (hereinafter referred to as glass fiber composite material) have replaced metal boxes as the mainstream box in new power systems due to their high specific strength, resistance to environmental aging and excellent electrical insulation properties.

[0003] With the upgrading and transformation of power distribution networks, a large number of fiberglass composite metering boxes that have reached the end of their service life have been decommissioned, resulting in a huge number of abandoned metering boxes. However, these abandoned boxes are difficult to regenerate using conventional methods. The thermosetting resin in the composite material forms a permanent three-dimensional network structure after curing, which cannot be restored to its plasticity by heating and melting or solvent dissolution. This renders the melting or dissolution processes used for recycling ordinary plastics ineffective. Secondly, its structural characteristics exacerbate the processing difficulty. Fiberglass composite boxes have the characteristics of "three highs and one thick," namely, a high fiberglass mass fraction (≥35%), a high degree of resin cross-linking, a complex rib structure, and a large wall thickness (3-6 mm). This causes traditional shredding equipment to experience rapid blade wear and frequent jamming during processing, resulting in severely insufficient processing capacity and making it difficult to obtain powder with controllable particle size suitable for subsequent use. Therefore, common disposal methods have been forced to shift to incineration or landfill, but this not only causes secondary pollution but also means that high-value fiberglass and resin resources are wasted.

[0004] Therefore, how to achieve the recycling of waste glass fiber composite metering boxes has become a technical problem that urgently needs to be solved in this field. Summary of the Invention

[0005] This invention aims to address one of the technical problems in related technologies to a certain extent. To this end, this invention provides a method for regenerating waste glass fiber composite material metering boxes, which can achieve the harmless treatment of waste glass fiber composite material metering boxes and realize resource regeneration.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: A method for regenerating waste glass fiber composite metering boxes includes the following steps: S1. Metering box for recycling waste glass fiber composite materials; S2. The waste glass fiber composite material metering box is subjected to multi-stage crushing and screening to obtain powder; S3. Weigh the raw materials according to the following weight parts and mix them evenly to obtain a mixture: 10-70 parts of the powder, 5-25 parts of the resin, 0.2-5 parts of the curing agent, 10-50 parts of the glass fiber, 0-40 parts of the flame retardant, 0-15 parts of the filler, 0-1 parts of the dispersant, 1-5 parts of the activator, and 0-5 parts of the catalyst. S4. The mixture is sequentially spread and hot-pressed for curing to obtain a glass fiber composite material board; S5, which uses glass fiber composite material sheets to make a new glass fiber composite material metering box.

[0007] In this application, "waste glass fiber composite metering box" refers to a discarded metering box whose performance has severely degraded due to physical and chemical aging caused by reaching or exceeding its design service life, thus failing to meet the original metering, protection, or structural strength requirements and being replaced or phased out. The glass fiber composite material can be glass fiber reinforced unsaturated polyester resin or glass fiber reinforced epoxy resin. The recycling method in this application includes the entire process from recycling the waste metering box to manufacturing a new metering box, and decomposes the conversion of the waste glass fiber composite metering box into several standardized operational steps, providing a directly implementable solution for large-scale, industrialized recycling. In step S2, the waste glass fiber composite metering box undergoes multi-stage crushing and screening to obtain powder. In step S3, the powder, resin, glass fiber, activator, and other raw materials are mixed evenly in a certain proportion to obtain a mixture. In step S4, the mixture is made into glass fiber composite sheet. Finally, in step S5, the sheet is used to manufacture a new glass fiber composite metering box. The recycling method in this application compensates for the performance loss caused by aging of the waste box powder by simultaneously introducing new resin, new glass fiber, activator, catalyst and other components, and further optimizes the performance of glass fiber composite material. This ensures that the resulting glass fiber composite material sheet has sufficient mechanical strength, electrical properties and durability to meet the manufacturing requirements of the new glass fiber composite metering box.

[0008] Optionally, in step S2, the multi-stage crushing includes primary crushing, coarse crushing, and fine crushing performed sequentially; the waste glass fiber composite material metering box is crushed into sheet material after primary crushing, the sheet material is crushed into crushed material after coarse crushing, and the crushed material is crushed into debris after fine crushing.

[0009] Primary crushing first breaks down the complex, reinforced waste metering box into flakes, reducing its overall structural strength and preventing frequent jamming when the processing equipment directly fine-crushes the intact box. Secondary coarse crushing further breaks down the flakes into smaller pieces, reducing their size and breakage resistance, making their shape more suitable for the subsequent fine crushing equipment and increasing processing throughput. Finally, fine crushing pulverizes the smaller pieces into smaller fragments. The fragments obtained after three stages of crushing have a more concentrated particle size distribution and more regular shape, facilitating subsequent screening to obtain recycled powder that meets the target particle size range.

[0010] Optionally, the initial crushing includes: using a twin-shaft shredder to shred the waste glass fiber composite material metering box into sheet-like materials with a length and width of 5 to 50 cm.

[0011] The initial crushing step, by using a twin-shaft shredder and limiting the size range of the output material (5–50 cm), lays a high-efficiency and controllable foundation for multi-stage crushing. The twin-shaft shredder possesses powerful shearing and tearing capabilities, quickly breaking down the entire waste bin into appropriately sized flakes. This avoids severe equipment jamming and impact damage caused by excessively large material sizes in subsequent fine crushing stages, improving the operational stability and safety of the production line. Furthermore, controlling the material size initially within the centimeter range provides a uniform and easily transportable feed for the subsequent coarse crushing process.

[0012] Optionally, the coarse crushing includes: using a twin-shaft shredder to shred the flaky material into fragments with a particle size of 10-50 mm.

[0013] The coarse crushing process utilizes a twin-shaft shredder to further process the centimeter-sized flakes from the initial crushing into millimeter-sized fragments, achieving precise control over material size. The coarse crushing produces uniform fragments with a particle size of 10–50 mm, providing a suitable feed size for subsequent fine crushing equipment. This size range ensures the processing capacity of the fine crushing equipment while avoiding the risks of overload, overheating, or jamming due to excessive feed size, and also prevents energy waste and over-grinding due to insufficient feed size. Furthermore, by setting a specific particle size target (10–50 mm), the coarse crushing process can be quantified, facilitating control over the quality of the generated fragments.

[0014] Optionally, the fine crushing includes: using a high-speed crusher with a rotation speed of 30,000~39,000 rpm to crush the material into fragments, wherein the high-speed crusher is set to: after each 20~40s of opening the crushing mode, close the crushing mode for 40~60s, and control the temperature of the material being crushed during the crushing process to be ≤60℃.

[0015] A high-speed crusher with a spindle speed of 30,000~39,000 rpm is used to provide extremely high mechanical impact and shear force to crush millimeter-sized materials into even finer fragments. Utilizing the instantaneous microscopic temperature rise and mechanical shear force generated by high-speed crushing, the old cross-linked network on the surface of the waste resin matrix undergoes partial depolymerization or microcrack propagation, exposing fresh polar groups (such as hydroxyl and carboxyl groups). This creates conditions for subsequent screening to obtain the target powder, solving the problem of traditional equipment's inability to achieve fine particle size. The high-speed crusher is set to a cyclic mode of "running for 20-40 seconds, intermittently stopping for 40-60 seconds." That is, after each 20-40 seconds of operation, the crushing mode is stopped for 40-60 seconds, then restarted for 20-40 seconds, and then stopped for 40-60 seconds, continuously repeating this process until most of the material is crushed to the target particle size.

[0016] Optionally, in step S2, the sieving includes: sieving out 30-300 mesh debris through a sieve as the powder.

[0017] By sieving to remove excessively coarse (less than 30 mesh) and excessively fine (greater than 300 mesh) debris, the selected powder is ensured to have a controllable particle size distribution. Powder with uniform particle size can achieve more uniform dispersion and encapsulation when subsequently mixed with raw materials such as new resin or new glass fiber, laying the foundation for the preparation of dense, uniformly performing recycled boards.

[0018] Optionally, in step S4, the fabric includes: providing a hot press mold, and uniformly spreading the mixture in the mold cavity of the hot press mold.

[0019] Uniform material distribution within the mold cavity ensures the homogeneity of the mixture, preventing uneven material accumulation. This allows for uniform pressure and flow during subsequent hot pressing, preventing defects such as uneven thickness, air bubbles, or resin aggregation in the finished sheet. Furthermore, confining the material distribution to the mold cavity allows the shape, size, and thickness of each molded sheet to be pre-set, guaranteeing product consistency.

[0020] Optionally, in step S4, the hot-press curing includes: first, pre-pressing the mixture in the mold cavity at pressures of 2 MPa, 4 MPa, and 8 MPa in sequence, with a pre-pressing time of 5 minutes for each pressure stage; and then performing final pressure curing at a pressure of 16 MPa.

[0021] Hot-press curing refers to a molding method that uses the simultaneous application of heat and pressure to induce an irreversible chemical reaction (curing) in the resin matrix, thereby bonding glass fibers and other raw materials. By setting a gradually increasing gradient pressure, maintaining each pressure stage for 5 minutes, during the low-pressure stages (2MPa, 4MPa), the low-viscosity resin can fully penetrate the gaps and surfaces between the powder and glass fibers, as well as the microcracks in the old powder, while gradually and smoothly expelling air and volatile components from the material. This avoids problems such as interface defects, bubbles, or uneven resin distribution caused by sudden high pressure. In other words, the gradually increasing pre-compression pressure allows the loose mixture to be gradually compacted. After completing the gradient pre-compression, a final pressure of 16MPa is applied for final curing, further closing micropores, compensating for resin curing shrinkage, achieving a highly dense board structure, and completing the final cross-linking and curing of the resin under this pressure, ensuring the recycled board has high mechanical strength.

[0022] Optionally, in step S3, the activator is one or more of the following: triethanolamine, dimethylethanolamine, dimethylcyclohexylamine, triethylamine, 1,5-diazabicyclo[4.3.0]non-5-ene, 1,8-diazabicyclo[5.4.0]undecyl7-ene, N,N-dimethylcyclohexylamine, hexadecyltrimethylammonium bromide, benzyltrimethylammonium hydroxide, and benzyltriethylammonium chloride.

[0023] Amine compounds such as triethanolamine and dimethylcyclohexylamine, as well as quaternary ammonium salts such as hexadecyltrimethylammonium bromide and benzyltrimethylammonium hydroxide, all contain highly polar functional groups (such as amino groups and quaternary ammonium ions). These highly polar functional groups can undergo physical adsorption or chemical reaction with hydroxyl and carboxyl groups present on the surface of powders made from aged glass fiber composites, thereby improving the chemical polarity, wettability, and reactivity of the powder surface and repairing the partially deactivated surface state due to aging. Furthermore, the functional groups in the activator can react with or form strong interactions with subsequently added resins (such as unsaturated polyester resins and epoxy resins) during hot-pressing curing, enhancing the interfacial adhesion strength between the powder and the newly added resin. Additionally, plasma treatment can be used to activate the powder surface.

[0024] Optionally, in step S3, the resin is one or more of unsaturated polyester resin, epoxy vinyl resin, or polyurethane resin; the curing agent is one or more of methyl ethyl ketone peroxide, benzoyl peroxide, tert-butyl perbenzoate, or tert-butyl hydroperoxide; the catalyst is one or more of 3-aminopropyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, or 3-methacryloyloxypropyltrimethoxysilane; the flame retardant is one or more of bromide, chloride, aluminum hydroxide, or phosphide flame retardants; the filler is one or more of calcium carbonate, silica fume, or talc; and the dispersant is one or more of polyvinyl alcohol, sodium polyacrylate, or sodium polymethacrylate.

[0025] Methyl ethyl ketone peroxide, benzoyl peroxide, tert-butyl perbenzoate, or tert-butyl hydroperoxide can all enable glass fibers and resins to cross-link and cure under a set hot-pressing curing process, forming a stable three-dimensional network structure. Silane catalysts can react with the hydroxyl groups on the surface of recycled powder and newly added glass fibers, while their organic functional groups can chemically bond with the resin matrix, thereby improving the interfacial bonding strength between the inorganic reinforcing phase and the organic resin matrix. Flame retardants give the manufactured recycled boards high flame retardancy; the addition of fillers can adjust flowability and reduce costs; dispersants can ensure the uniform dispersion of powder and fillers in the resin, avoid agglomeration, and ensure the uniformity of the properties of the manufactured boards.

[0026] These features and advantages of the present invention will be disclosed in detail in the following specific embodiments and accompanying drawings. The preferred embodiments or means of the present invention will be shown in detail in conjunction with the accompanying drawings, but are not intended to limit the technical solutions of the present invention. In addition, each of these features, elements and components appearing in the following text and drawings is a plurality of, and different symbols or numbers are used for convenience of representation, but all represent parts with the same or similar construction or function. Attached Figure Description

[0027] The present invention will be further described below with reference to the accompanying drawings: Figure 1 This is a schematic flowchart of the regeneration method for the waste glass fiber composite material metering box in this invention. Detailed Implementation

[0028] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described are intended to explain the present invention and should not be construed as limiting the invention.

[0029] The terms "an embodiment," "example," or "trademark" used in this specification refer to a particular feature, structure, or characteristic described in connection with the embodiment itself that may be included in at least one embodiment disclosed in this patent. The phrase "in an embodiment" appearing in various places throughout the specification does not necessarily refer to the same embodiment.

[0030] Example: This embodiment provides a method for regenerating waste glass fiber composite metering boxes, such as... Figure 1 As shown, it includes the following steps: S1. Metering box for recycling waste glass fiber composite materials; S2. The waste glass fiber composite material metering box is subjected to multi-stage crushing and screening to obtain powder; S3. Weigh the raw materials according to the following weight parts and mix them evenly to obtain a mixture: 10-70 parts powder, 5-25 parts resin, 0.2-5 parts curing agent, 10-50 parts glass fiber, 0-40 parts flame retardant, 0-15 parts filler, 0-1 part dispersant, 1-5 parts activator, and 0-5 parts catalyst. S4. The mixture is sequentially spread and hot-pressed for curing to obtain a glass fiber composite material board. S5, which uses glass fiber composite material sheets to make a new glass fiber composite material metering box.

[0031] In this embodiment, the waste glass fiber composite metering box refers to a discarded box whose performance has severely degraded due to physical and chemical aging caused by reaching or exceeding its design service life, making it unable to meet the original metering, protection, or structural strength requirements, and thus being replaced or phased out. The glass fiber composite material can be glass fiber reinforced unsaturated polyester resin or glass fiber reinforced epoxy resin. The recycling method in this embodiment includes the entire process from recycling the waste box to manufacturing a new metering box, and decomposes the conversion of the waste glass fiber composite metering box into several standardized operational steps, providing a directly implementable solution for large-scale, industrialized recycling. In step S2, the waste glass fiber composite metering box undergoes multi-stage crushing and screening to obtain powder. In step S3, the powder, resin, glass fiber, activator, and other raw materials are mixed evenly in a certain proportion to obtain a mixture. In step S4, the mixture is made into glass fiber composite material sheets. Finally, in step S5, the sheets are used to manufacture a new glass fiber composite metering box. The regeneration method in this embodiment compensates for the performance loss caused by aging of the waste box powder by simultaneously introducing new resin, new glass fiber, activator, catalyst and other components, and further optimizes the performance of glass fiber composite material. This ensures that the resulting glass fiber composite material sheet has sufficient mechanical strength, electrical properties and durability to meet the manufacturing requirements of the new glass fiber composite metering box.

[0032] In step S2, the multi-stage crushing includes primary crushing, coarse crushing and fine crushing performed sequentially; the waste glass fiber composite material metering box is crushed into sheet material after primary crushing, the sheet material is crushed into crushed material after coarse crushing, and the crushed material is crushed into debris after fine crushing.

[0033] In this embodiment, primary crushing first breaks down the complex, reinforced waste metering box into flake-like material, reducing its overall structural strength and preventing frequent jamming issues when the processing equipment directly performs fine crushing on the intact box. Coarse crushing further breaks the flake-like material into smaller pieces, reducing its size and breakage resistance, making its shape more suitable for the subsequent fine crushing equipment and increasing processing throughput. Fine crushing finally pulverizes the smaller pieces into smaller fragments. The fragments obtained after three stages of crushing have a more concentrated particle size distribution and a more regular shape, facilitating subsequent screening to obtain recycled powder that meets the target particle size range.

[0034] The initial crushing process includes using a twin-shaft shredder to shred the waste glass fiber composite material metering box into sheet-like materials with a length and width of 5 to 50 cm.

[0035] In this embodiment, the initial crushing step, by selecting a twin-shaft shredder and limiting the size range of the output material (5-50cm), lays an efficient and controllable foundation for multi-stage crushing. The twin-shaft shredder has powerful shearing and tearing capabilities, enabling it to quickly decompose the entire waste container into appropriately sized flakes. This avoids severe equipment jamming and impact damage caused by excessively large material sizes in subsequent fine crushing stages, thus improving the operational stability and safety of the production line. On the other hand, initially controlling the material size to the centimeter level also provides a uniform and easily transportable feed for the subsequent coarse crushing process.

[0036] Coarse crushing includes: using a twin-shaft shredder to shred flaky materials into fragments with a particle size of 10-50mm.

[0037] In this embodiment, the coarse crushing process utilizes a twin-shaft shredder to further process the centimeter-sized flakes obtained from the initial crushing into millimeter-sized fragments, achieving precise control over material size. The coarse crushing produces uniform fragments with a particle size of 10–50 mm, providing a suitable feed size for subsequent fine crushing equipment. This size range ensures the processing capacity of the fine crushing equipment while avoiding the risks of equipment overload, overheating, or jamming due to excessive feed size, and also avoids energy waste and over-grinding due to insufficient feed size. Furthermore, by setting a specific particle size target (10–50 mm), the coarse crushing process can be quantified, facilitating control over the quality of the generated fragments.

[0038] Fine crushing includes: using a high-speed crusher with a rotation speed of 30,000~39,000 rpm to crush the material into fragments. The high-speed crusher is set to: turn off the crushing mode for 40~60 seconds after each 20~40 seconds of operation, and control the temperature of the material being crushed to be ≤60℃ during the crushing process.

[0039] In this embodiment, a high-speed crusher with a spindle speed of 30,000~39,000 rpm is used to provide extremely high mechanical impact and shearing force to crush millimeter-sized materials into finer fragments, creating conditions for subsequent screening to obtain the target powder and solving the problem that traditional equipment cannot achieve fine particle size. The high-speed crusher is set to a cyclic mode of "running for 20~40s, intermittently stopping for 40~60s". That is, after each 20~40s of operation, the crushing mode is turned off for 40~60s, then restarted for 20~40s, and then turned off for 40~60s, and this process is continuously repeated until most of the material is crushed to the target particle size. It should be noted that starting the crushing mode means that the main shaft of the high-speed crusher rotates at a speed of 39,000 rpm and drives the cutters to crush the material, and turning off the crushing mode means that the main shaft of the high-speed crusher stops rotating. Through forced stop-and-go intervals, the material and equipment can dissipate heat, suppressing the drastic temperature rise caused by continuous high-speed friction and avoiding the overheating problem in the existing crushing process. Furthermore, by controlling the material temperature to ≤60℃ during the fine crushing process, the thermosetting material, glass fiber composite, was prevented from softening due to friction and sticking to the cutting tools, thus significantly reducing tool wear. Moreover, temperature control also helps maintain the integrity of the glass fibers, preventing excessive fiber breakage and uneven distribution caused by overheating. This ultimately yields recycled powder with uniform particle size and stable quality, laying the structural foundation for the subsequent preparation of high-performance composite material sheets.

[0040] In step S2, sieving includes: sieving out 30-300 mesh debris through a sieve as powder.

[0041] In this embodiment, excessively coarse (less than 30 mesh) and excessively fine (greater than 300 mesh) debris is removed by sieving to ensure that the selected powder has a controllable particle size distribution. Powder with uniform particle size can achieve more uniform dispersion and encapsulation when subsequently mixed with raw materials such as new resin or new glass fiber, laying the foundation for preparing recycled boards with a dense structure and uniform performance.

[0042] In step S4, the fabric includes: providing a hot press mold, and evenly spreading the mixture in the mold cavity of the hot press mold.

[0043] In this embodiment, uniform material distribution within the mold cavity is ensured through even spreading, preventing uneven material accumulation. This allows for uniform pressure and flow during subsequent hot pressing, preventing defects such as uneven thickness, air bubbles, or resin aggregation in the finished sheet. Furthermore, confining the material spreading operation within the mold cavity ensures that the shape, size, and thickness of each molded sheet are pre-set by the mold, guaranteeing product specification consistency.

[0044] In step S4, hot pressing curing includes: first, pre-pressing the mixture in the mold cavity at pressures of 2 MPa, 4 MPa, and 8 MPa, with each pressure stage lasting 5 minutes; and then performing final pressing curing at 16 MPa.

[0045] In this embodiment, hot-press curing refers to a molding method in which an irreversible chemical reaction (curing) occurs in the resin matrix under the simultaneous application of heat and pressure, thereby bonding the glass fiber and other raw materials. By setting a gradient pressure that gradually increases from low to high and maintaining each pressure stage for 5 minutes, the low-viscosity resin can fully penetrate into the gaps and surface of the powder and glass fiber under low pressure. At the same time, air and volatile components in the material are gradually and gently discharged, avoiding problems such as interface defects, bubbles, or uneven resin distribution caused by sudden high pressure. That is, by gradually increasing the pre-compression pressure, the loose mixture can be gradually compacted. After completing the gradient pre-compression, a final pressure of 16 MPa is applied for final pressure curing to further eliminate micropores, making the board structure highly dense. Under this pressure, the final cross-linking and curing of the resin is completed, ensuring that the recycled board has high mechanical strength.

[0046] In step S3, the activator is one or more of the following: triethanolamine, dimethylethanolamine, dimethylcyclohexylamine, triethylamine, 1,5-diazabicyclo[4.3.0]non-5-ene, 1,8-diazabicyclo[5.4.0]undecyl7-ene, N,N-dimethylcyclohexylamine, hexadecyltrimethylammonium bromide, benzyltrimethylammonium hydroxide, and benzyltriethylammonium chloride.

[0047] In this embodiment, amine compounds such as triethanolamine and dimethylcyclohexylamine, as well as quaternary ammonium salts such as hexadecyltrimethylammonium bromide and benzyltrimethylammonium hydroxide, all contain highly polar functional groups (such as amino groups and quaternary ammonium ions). These highly polar functional groups can undergo physical adsorption or chemical reaction with hydroxyl and carboxyl groups present on the surface of powders made from aged glass fiber composite materials, thereby improving the chemical polarity, wettability, and reactivity of the powder surface and repairing the partially deactivated surface state due to aging. Furthermore, the functional groups in the activator can also react with subsequently added resins (such as unsaturated polyester resins and epoxy resins) during hot-press curing or form strong interactions, enhancing the interfacial adhesion strength between the powder and the newly added resin. Additionally, plasma treatment can be used to activate the powder surface.

[0048] In step S3, the resin is one or more of unsaturated polyester resin, epoxy vinyl resin, or polyurethane resin; the curing agent is one or more of methyl ethyl ketone peroxide, benzoyl peroxide, tert-butyl perbenzoate, or tert-butyl hydroperoxide; the catalyst is one or more of 3-aminopropyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, or 3-methacryloyloxypropyltrimethoxysilane; the flame retardant is one or more of bromide, chloride, aluminum hydroxide, or phosphide flame retardants; the filler is one or more of calcium carbonate, silica fume, or talc; and the dispersant is one or more of polyvinyl alcohol, sodium polyacrylate, or sodium polymethacrylate.

[0049] In this embodiment, methyl ethyl ketone peroxide, benzoyl peroxide, tert-butyl perbenzoate, or tert-butyl hydroperoxide can all enable the glass fiber and resin to crosslink and cure under a set hot-press curing process, forming a stable three-dimensional network structure. Silane catalysts can react with the hydroxyl groups on the surface of the recycled powder and newly added glass fibers, while their organic functional groups can chemically bond with the resin matrix, thereby improving the interfacial bonding strength between the inorganic reinforcing phase and the organic resin matrix. Flame retardants give the manufactured recycled boards high flame retardancy; the addition of fillers can adjust flowability and reduce costs; dispersants can ensure the uniform dispersion of powder and fillers in the resin, avoid agglomeration, and ensure the uniformity of the properties of the manufactured boards.

[0050] In other embodiments, coarse crushing and primary crushing may also employ shear crushers or hammer crushers.

[0051] Preparation Example 1: Measuring boxes made from recycled waste glass fiber reinforced unsaturated polyester resin were processed. The recycled waste measuring boxes were shredded using a twin-shaft shredder to obtain sheet-like materials with a length and width of 5–50 cm. The sheet-like materials were then further shredded into fragments with a particle size of 10–50 mm using a twin-shaft shredder. These fragments were then further pulverized into small pieces using a high-speed grinder, and the small pieces with a particle size of 10–50 mm were sieved out for subsequent use as powder. The raw materials were weighed and mixed evenly according to the following parts by weight: 50 parts of the aforementioned powder, 15 parts of unsaturated polyester resin, 1 part of methyl ethyl ketone peroxide, 25 parts of glass fiber, 20 parts of aluminum hydroxide, 10 parts of calcium carbonate, 0.5 parts of polyvinyl alcohol, 2 parts of N,N-dimethylcyclohexylamine, and 1 part of 3-glycidyl etheroxypropyltrimethoxysilane. The mixture was evenly spread into the mold cavity and hot-pressed at 145 ℃ and 8 MPa for 12 minutes to obtain the board material. The sheet material has the following properties: flexural strength of 152 MPa and impact strength of 58 kJ / m. 2 PTI (tracking resistance index) ≥600, flame retardant rating is UL94 V-0.

[0052] Preparation Example 2: Metering boxes made from recycled waste glass fiber reinforced epoxy vinyl ester resin were processed. The recycled waste metering boxes were shredded using a twin-shaft shredder to obtain sheet-like materials with a length and width of 5–50 cm. The sheet-like materials were then further shredded into fragments with a particle size of 10–50 mm using a twin-shaft shredder. These fragments were then further pulverized into small pieces using a high-speed grinder, and the small pieces with a particle size of 8–10 mm were sieved out for subsequent use as powder. The raw materials were weighed and mixed evenly according to the following parts by weight: 30 parts of the aforementioned powder, 20 parts of epoxy vinyl ester resin, 1.5 parts of benzoyl peroxide, 40 parts of glass fiber, 10 parts of brominated flame retardant, 5 parts of silica fume, 0.3 parts of sodium polyacrylate, 1 part of hexadecyltrimethylammonium bromide, and 0.5 parts of 3-methacryloyloxypropyltrimethoxysilane. The mixture was evenly spread into the mold cavity and hot-pressed and cured at 155 °C and 10 MPa for 10 minutes to obtain the board material. The sheet material has the following properties: flexural strength of 168 MPa and impact strength of 63 kJ / m. 2 With a PTI of 650, it is suitable for high-humidity coastal environments.

[0053] Preparation Example 3: Waste glass fiber reinforced polyurethane resin metering boxes are recycled. The recycled waste metering boxes are crushed using a twin-shaft shredder to obtain sheet material. The sheet material is then further crushed into fragments with a particle size of 10–50 mm using the twin-shaft shredder. These fragments are then further pulverized by a high-speed grinder and air-classified to obtain powder with a particle size of 15–30 mm for subsequent use. The raw materials are weighed and mixed evenly according to the following parts by weight: 40 parts of the aforementioned powder, 25 parts of polyurethane resin, 0.5 parts of curing agent, 20 parts of glass fiber, 15 parts of phosphorus-based flame retardant, 8 parts of talc, 0.5 parts of polyvinyl alcohol, 3 parts of triethanolamine, and 1 part of 3-aminopropyltriethoxysilane. The mixture is evenly spread into the mold cavity and cured using a two-stage hot-pressing process: first, pre-pressing at 130 °C and 3 MPa for 3 minutes, and then final pressing at 150 °C and 7 MPa for 10 minutes to obtain the board material. The sheet material has the following properties: flexural strength of 148 MPa and impact strength of 72 kJ / m. 2 With a PTI of 600, the plate prepared in this example exhibits a significant advantage in toughness.

[0054] Preparation Example 4: Waste glass fiber reinforced unsaturated polyester resin metering boxes were recycled. The recycled metering boxes were shredded using a twin-shaft shredder to obtain sheet-like materials with a length and width of 5–50 cm. The sheet-like materials were then further shredded into smaller pieces with a particle size of 10–50 mm using the twin-shaft shredder. These smaller pieces were then further pulverized into smaller fragments using a high-speed pulverizer, and classified using a combination of a vibrating screen and an air classifier to remove fragments with a particle size of 20–40 mm, while also removing excessively long fibers and metallic impurities. The raw materials were weighed and mixed evenly according to the following parts by weight: 70 parts of the aforementioned powder, 10 parts of unsaturated polyester resin, 1 part of methyl ethyl ketone peroxide, 15 parts of glass fiber, 8 parts of aluminum hydroxide, 5 parts of calcium carbonate, 0.2 parts of polyvinyl alcohol, 1 part of N,N-dimethylcyclohexylamine, and 0.2 parts of 3-glycidyl etheroxypropyltrimethoxysilane. The mixture was evenly spread into the mold cavity and hot-pressed at 145 ℃ and 9 MPa for 15 minutes to obtain the board material. The sheet material has the following properties: flexural strength of 142 MPa and impact strength of 55 kJ / m. 2 The high content of powder used in this preparation example reduces the overall cost.

[0055] Preparation Example 5: Waste glass fiber reinforced epoxy vinyl ester resin metering boxes were recycled. The recycled metering boxes were shredded using a twin-shaft shredder to obtain sheet-like materials with a length and width of 5–50 cm. The sheet-like materials were then further shredded into fragments with a particle size of 10–50 mm using a twin-shaft shredder. These fragments were then further pulverized into small pieces using a high-speed grinder, and the small pieces with a particle size of 5–20 mm were sieved out for subsequent use as powder. The raw materials were weighed and mixed evenly according to the following parts by weight: 35 parts of the aforementioned powder, 18 parts of epoxy vinyl ester resin, 1.2 parts of tert-butyl perbenzoate, 30 parts of glass fiber, 30 parts of phosphorus-nitrogen flame retardant, 8 parts of silica fume, 0.3 parts of sodium polyacrylate, 3 parts of N,N-dimethylcyclohexylamine, and 0.8 parts of 3-glycidyl etheroxypropyltrimethoxysilane. The mixture was evenly spread into the mold cavity and hot-pressed at 160 ℃ and 10 MPa for 12 minutes to obtain the board material. The performance of this sheet material is as follows: flame retardant rating reaches UL94 V-0, bending strength is 165 MPa, and after aging in hot air at 120 ℃ for 500 hours, its bending strength retention rate is not less than 90%.

[0056] Preparation Example 6: Waste glass fiber reinforced unsaturated polyester resin metering boxes were recycled. The recycled waste metering boxes were shredded using a twin-shaft shredder to obtain sheet-like materials with a length and width of 5–50 cm. The sheet-like materials were then further shredded into fragments with a particle size of 10–50 mm using a twin-shaft shredder. These fragments were then further pulverized into small pieces using a high-speed grinder, and the small pieces with a particle size of 10–25 mm were sieved out for subsequent use as powder. The powder was then surface-activated using plasma treatment. The raw materials were weighed and mixed evenly according to the following parts by weight: 45 parts of the aforementioned powder, 20 parts of unsaturated polyester resin, 1 part of benzoyl peroxide, 30 parts of glass fiber, 15 parts of bromine-antimony composite flame retardant, 10 parts of calcium carbonate, 0.5 parts of sodium polyacrylate, 2 parts of benzyltrimethylammonium hydroxide, and 1.5 parts of a mixed catalyst composed of 3-aminopropyltriethoxysilane and 3-methacryloyloxypropyltrimethoxysilane in a 1:1 mass ratio. The mixture was evenly spread into the mold cavity and hot-pressed and cured at 150℃ and 8 MPa for 10 minutes to obtain the sheet material. The sheet material has the following properties: flexural strength up to 170 MPa and impact strength up to 60 kJ / m. 2 Water absorption rate decreases, and interfacial bonding performance is enhanced.

[0057] The above are merely specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Those skilled in the art should understand that the present invention includes, but is not limited to, the contents described in the accompanying drawings and the specific embodiments above. Any modifications that do not depart from the functional and structural principles of the present invention will be included within the scope of the claims.

Claims

1. A method for regenerating waste glass fiber composite metering boxes, characterized in that, Includes the following steps: S1. Metering box for recycling waste glass fiber composite materials; S2. The waste glass fiber composite material metering box is subjected to multi-stage crushing and screening to obtain powder; S3. Weigh the raw materials according to the following weight parts and mix them evenly to obtain a mixture: 10-70 parts of the powder, 5-25 parts of the resin, 0.2-5 parts of the curing agent, 10-50 parts of the glass fiber, 0-40 parts of the flame retardant, 0-15 parts of the filler, 0-1 parts of the dispersant, 1-5 parts of the activator, and 0-5 parts of the catalyst. S4. The mixture is sequentially spread and hot-pressed for curing to obtain a glass fiber composite material board; S5, which uses glass fiber composite material sheets to make a new glass fiber composite material metering box.

2. The method for regenerating waste glass fiber composite material metering boxes according to claim 1, characterized in that, In step S2, the multi-stage crushing includes primary crushing, coarse crushing and fine crushing performed sequentially; the waste glass fiber composite material metering box is crushed into sheet material after primary crushing, the sheet material is crushed into crushed material after coarse crushing, and the crushed material is crushed into debris after fine crushing.

3. The method for regenerating waste glass fiber composite material metering boxes according to claim 2, characterized in that, The initial crushing includes: using a twin-shaft shredder to shred the waste glass fiber composite material metering box into sheet-like materials with a length and width of 5 to 50 cm.

4. The method for regenerating waste glass fiber composite material metering boxes according to claim 2, characterized in that, The coarse crushing includes: using a twin-shaft shredder to shred the flaky material into fragments with a particle size of 10-50mm.

5. The method for regenerating waste glass fiber composite material metering boxes according to claim 2, characterized in that, The fine crushing includes: using a high-speed crusher with a rotation speed of 30,000~39,000 rpm to crush the material into fragments. The high-speed crusher is set to: after each 20~40s of opening the crushing mode, close the crushing mode for 40~60s, and control the temperature of the material being crushed during the crushing process to be ≤60℃.

6. The method for regenerating waste glass fiber composite material metering boxes according to claim 2, characterized in that, In step S2, the sieving includes: sieving out 30-300 mesh debris through a sieve as the powder.

7. The method for regenerating waste glass fiber composite material metering boxes according to claim 1, characterized in that, In step S4, the fabric includes: providing a hot press mold, and uniformly spreading the mixture in the mold cavity of the hot press mold.

8. The method for regenerating waste glass fiber composite material metering boxes according to claim 7, characterized in that, In step S4, the hot-press curing includes: first, pre-pressing the mixture in the mold cavity at pressures of 2 MPa, 4 MPa, and 8 MPa, with each pre-pressing time being 5 minutes; and then performing final pressure curing at 16 MPa.

9. The method for regenerating waste glass fiber composite material metering boxes according to any one of claims 1-8, characterized in that, In step S3, the activator is one or more of the following: triethanolamine, dimethylethanolamine, dimethylcyclohexylamine, triethylamine, 1,5-diazabicyclo[4.3.0]non-5-ene, 1,8-diazabicyclo[5.4.0]undecyl7-ene, N,N-dimethylcyclohexylamine, hexadecyltrimethylammonium bromide, benzyltrimethylammonium hydroxide, and benzyltriethylammonium chloride.

10. The method for regenerating waste glass fiber composite material metering boxes according to any one of claims 1-8, characterized in that, In step S3, the resin is one or more of unsaturated polyester resin, epoxy vinyl resin, or polyurethane resin; the curing agent is one or more of methyl ethyl ketone peroxide, benzoyl peroxide, tert-butyl perbenzoate, or tert-butyl hydroperoxide; the catalyst is one or more of 3-aminopropyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, or 3-methacryloyloxypropyltrimethoxysilane; the flame retardant is one or more of bromide, chloride, aluminum hydroxide, or phosphide flame retardants; the filler is one or more of calcium carbonate, silica fume, or talc; and the dispersant is one or more of polyvinyl alcohol, sodium polyacrylate, or sodium polymethacrylate.

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