Cement-based composite fiber manufacturing apparatus

Abstract

This invention discloses a cement-based composite fiber manufacturing equipment, comprising a pulping tank, an extrusion feeder, a fiber forming component, a non-aqueous coagulation bath, and a continuous drawing mechanism. The pulping tank mixes the raw material system and produces a spinnable pulp. The extrusion feeder is connected to both the pulping tank and the fiber forming component, and conveys the spinnable pulp to the fiber forming component. The fiber forming component forms the spinnable pulp into fibrous streams and conveys them to the non-aqueous coagulation bath. The non-aqueous coagulation bath contains a non-aqueous coagulation medium, which solidifies and shapes the fibrous streams into nascent composite fibers, and then conveys the nascent composite fibers to the continuous drawing mechanism. The continuous drawing mechanism continuously draws and stretches the nascent composite fibers to modify them into cement-based composite fibers. This allows for continuous production of cement-based composite fibers with a simple process, and the entire process does not introduce free water, thus preserving the characteristics of the cement-based powder phase.

Description

Technical Field

[0001] This invention belongs to the field of cement-based composite fiber preparation technology, and particularly relates to a cement-based composite fiber manufacturing equipment. Background Technology

[0002] Cement-based composite fibers are a type of fibrous composite material made by compounding cement-based powder with a polymer system to form a spinnable slurry, followed by fiberization treatment. They possess advantages such as high temperature resistance, corrosion resistance, and good compatibility with the cement matrix. Existing cement-based composite fiber production technologies mainly include mechanical drawing, die extrusion, and jet atomization. These methods generally suffer from low production efficiency, poor fiber performance stability, and insufficient equipment automation, making it difficult to meet the large-scale demand for high-performance cement-based composite fibers in the modern construction industry.

[0003] For example, the content disclosed in document CN114290485A, "A Continuous Molding Device and Method for Fiber-Toughened Cement-Based Composite Material Products", has solved the problem of long demolding time and difficulty in continuous production of cement-based composite material products to a certain extent. However, its molding objects are mainly tubular, plate-shaped, and other block or plate-like products. It relies on the mold to constrain the slurry as a whole for molding. Its core technology lies in the coupling of molding and demolding processes, and does not involve the problem of continuous extrusion, stretching, and directional molding of cement-based materials in the form of filaments or fibers.

[0004] For example, the content disclosed in document CN116555942A, "Preparation method and application of a core-shell structure hydraulic organic-inorganic composite material", mainly relies on chemical reactions and multi-step processes to complete the material structure construction. The process is complex and has poor continuity. It does not involve continuous extrusion, stretching and tension control of spinnable sizing by mechanical means, which is difficult to meet the needs of large-scale and continuous industrial production of cement-based composite fibers.

[0005] In the field of cement-based fiber preparation, existing technologies mostly employ short fiber blending, compression molding, or intermittent extrusion methods. These methods generally suffer from low production efficiency, poor fiber size consistency, insufficient fiber continuity, and low equipment system integration, making it difficult to achieve continuous and stable operation of fiber production from raw material supply, pulping, forming, curing to drawing and collection. In particular, for spinnable pulps formed by blending cement-based powders and liquid polymers, existing technologies lack suitable continuous production equipment and processes. Summary of the Invention

[0006] In order to solve the above-mentioned technical problems, the purpose of this invention is to provide a cement-based composite fiber manufacturing equipment with a simple structure and simple process, which can produce cement-based composite fibers in an anhydrous system.

[0007] To achieve the above objectives, the technical solution of the present invention is as follows: A cement-based composite fiber manufacturing equipment, comprising a pulping tank, an extrusion feeding component, a fiber forming component, a non-aqueous coagulation bath component, and a continuous drawing mechanism arranged in sequence; The pulping tank is used to mix the raw material system consisting of cement-based powder phase, reinforcing phase, anhydrous liquid polymer compound and anhydrous trace additives and make it into a spinnable pulp. The extrusion feeder is connected to the pulping tank and the fiber forming component respectively. The extrusion feeder is used to transport the spinnable pulp produced by the pulping tank to the fiber forming component. The fiberized forming part is used to form the spinnable slurry into fibrous streams and transport them to the non-aqueous coagulation bath; The non-aqueous coagulation bath contains a non-aqueous coagulation medium. The non-aqueous coagulation bath is used to solidify and shape the fibrous streams passing through it into nascent composite fibers, and to transport the nascent composite fibers to the continuous drawing mechanism. The continuous drawing mechanism is used to continuously draw and stretch the nascent composite fibers to modify them and obtain cement-based composite fibers.

[0008] Based on the above technical solution, the present invention can be further improved as follows: Furthermore, the raw material system satisfies at least one of the following conditions AE: A: The components of the raw material system, by mass fraction, are as follows: the content of the cement-based powder phase is 55-70 wt%, the content of the reinforcing phase is 1-5 wt%, the content of the anhydrous trace additives is 1-4 wt%, and the balance is anhydrous liquid polymer compound. B: The cement-based powder phase comprises a main binder and a SiO2-CaO binary system, wherein the main binder is at least one of ordinary Portland cement, rapid-hardening sulfoaluminate cement and aluminate cement; C: The reinforcing phase is at least one of whiskers and chopped fibers. The whiskers are at least one of calcium carbonate whiskers, calcium sulfate whiskers, zinc oxide whiskers, and silicon carbide whiskers, and the aspect ratio of the whiskers is 10-30. The chopped fibers are at least one of anhydrous polypropylene chopped fibers, polyimide chopped fibers, and basalt chopped fibers, and the length of the chopped fibers is 1-3 mm. D: The anhydrous liquid polymer compound is composed of a main liquid polymer, a co-crosslinking polymer, and a latent curing agent. The main liquid polymer is at least one of anhydrous polyethylene glycol, anhydrous liquid acrylate oligomer, and anhydrous liquid polybutadiene. The co-crosslinking polymer is at least one of anhydrous liquid epoxy resin oligomer and anhydrous hydroxyl-terminated polyurethane prepolymer. The latent curing agent is at least one of anhydrous amine latent curing agent and anhydrous benzoyl peroxide latent curing agent. E: The anhydrous trace additive is at least one of anhydrous polycarboxylate superplasticizer powder, anhydrous glyceryl stearate, anhydrous organosilicon defoamer, and anhydrous fumed silica.

[0009] Furthermore, it also includes a winding mechanism disposed on the side of the continuous drawing mechanism away from the non-aqueous curing bath, which is used to provide traction force to the cement-based composite fiber and wind it up.

[0010] Furthermore, the pulping tank includes a tank body and a stirring component. The upper end of the tank body is provided with a feeding port, and the lower end of the tank body is provided with a pulp outlet. The stirring component is disposed on the tank body, and its stirring part is located inside the tank body. The stirring component includes a driving component, a stirring shaft, and a shearing blade. The stirring shaft is vertically arranged and passes through the tank body, and is rotatably connected to the tank body. The stirring shaft is drively connected to the driving component located outside the tank body. The shearing blade is located inside the tank body and is disposed on the stirring shaft.

[0011] Furthermore, the extrusion feeder includes a feed pump, a flow meter, and a pressure equalization and flow stabilization container. The pulping tank, feed pump, pressure equalization and flow stabilization container, and fiber forming component are connected in sequence. The flow meter is located at the connection between the feed pump and the pressure equalization and flow stabilization container. The feed pump is used to transport the spinnable pulp in the pulping tank to the pressure equalization and flow stabilization container. The pressure equalization and flow stabilization container is used to buffer the feed pressure of the spinnable pulp and supply it to the fiber forming component.

[0012] Furthermore, the fibrous formed part includes a screw extruder and a spinneret, the spinneret being disposed at the outlet end of the screw extruder, and the inlet end of the screw extruder being connected to the extrusion feeder.

[0013] Furthermore, the non-aqueous coagulation bath includes a coagulation bath tank and a lower pressure roller. One end of the coagulation bath tank is provided with an inlet hole, and the inlet hole is connected to the spinneret. The lower pressure roller is horizontally arranged and rotatably installed in the coagulation bath tank. The coagulation bath tank contains a non-aqueous coagulation medium. The lower pressure roller and the inlet hole are both immersed below the liquid surface of the non-aqueous coagulation medium. After the fibrous stream is squeezed into the coagulation bath tank through the inlet hole, it passes under the lower pressure roller to immerse itself in the non-aqueous coagulation medium and is finally discharged out of the coagulation bath tank.

[0014] Furthermore, a heating device is provided between the non-aqueous coagulation bath and the continuous drawing mechanism. The non-aqueous coagulation medium is an anhydrous organic solvent, and the heating device is used to heat the nascent composite fiber.

[0015] Furthermore, the heating device includes a housing and a heating element disposed within the housing. The housing has mutually aligned perforations at both ends to allow the nascent composite fibers to pass through it. The housing also has a negative pressure interface for communicating with the air intake of a negative pressure device.

[0016] Furthermore, the continuous drafting mechanism includes a vertical plate, a tension testing device, a counterweight roller, and at least two guide rollers. Multiple guide rollers are spaced apart on the vertical plate along the feeding direction of the nascent composite fiber. All guide rollers are horizontally positioned, with one end vertically rotatably connected to the vertical plate. A counterweight roller is positioned below any two adjacent guide rollers and is vertically slidably connected to the vertical plate. The counterweight roller is parallel to the guide rollers. The nascent composite fiber bends and passes sequentially around the counterweight roller and guide roller. The tension testing device is positioned between any guide roller and the corresponding counterweight roller, with its sensing end contacting the corresponding point of the nascent composite fiber to measure the tension borne by the nascent composite fiber.

[0017] Compared with the prior art, the beneficial effects of the embodiments of the present invention are as follows: continuous production of cement-based composite fibers can be realized from the equipment level, and the process is simple. The whole process does not introduce free water, thus maintaining the characteristics of the cement-based powder phase. When the cement-based composite fibers are used later, they are brought into contact with water, so that the cement-based separate phase undergoes a hydration reaction, that is, it is solidified into cement products.

[0018] In terms of raw material system, a spinnable slurry is prepared by mixing cement-based powder phase and anhydrous liquid polymer compound, and then the spinnable slurry is extruded to form fibrous fine streams. When the fibrous fine streams come into contact with non-aqueous solidification media, the polymer materials in the fibrous fine streams can undergo cross-linking reaction to form a three-dimensional tough skeleton, while the cement-based powder phase and reinforcing phase are embedded in the three-dimensional tough skeleton. After drying and stretching, the nascent composite fibers of Deao have good toughness and tensile properties. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of the cement-based composite fiber manufacturing equipment described in an embodiment of the present invention; Figure 2 This is a schematic diagram of the structure of the pulping tank described in an embodiment of the present invention; Figure 3 This is a schematic diagram of the structure of the fibrous formed part, the non-aqueous coagulation bath part, and the continuous drawing mechanism described in the embodiments of the present invention; Figure 4 This is a schematic diagram of the structure of the fiberized forming part, the non-aqueous coagulation bath part, the heating device and the continuous stretching mechanism described in the embodiments of the present invention.

[0020] In the diagram: 1. Pulping tank; 11. Tank body; 111. Feed port; 112. Pulp outlet; 12. Agitator; 121. Drive unit; 122. Agitator shaft; 123. Shear blade; 2. Extrusion feed unit; 21. Feed pump; 22. Flow meter; 23. Pressure equalization and flow stabilization container; 3. Fiber forming unit; 31. Screw extruder; 32. Spinneret; 4. Non-aqueous coagulation bath; 41. Coagulation bath tank; 411. Inlet hole; 42. Lower pressure roller; 5. Continuous drawing mechanism; 51. Vertical plate; 52. Tension testing device; 53. Counterweight roller; 54. Guide roller; 6. Rewinding mechanism; 7. Heating device; 71. Shell; 711. Perforation; 712. Negative pressure interface; 72. Heating element. Detailed Implementation

[0021] The principles and features of the present invention are described below with reference to the accompanying drawings. The examples given are for illustrative purposes only and are not intended to limit the scope of the invention. The invention is described more specifically in the following paragraphs by way of example with reference to the accompanying drawings. The advantages and features of the invention will become clearer from the following description and claims. It should be noted that the drawings are in a very simplified form and use non-precise proportions, and are only used to facilitate and clarify the illustration of the embodiments of the invention.

[0022] like Figure 1As shown, this embodiment provides a cement-based composite fiber manufacturing equipment, including a pulping tank 1, an extrusion feeder 2, a fiber forming component 3, a non-aqueous coagulation bath 4, and a continuous drawing mechanism 5 arranged sequentially. The pulping tank 1 is used to mix a raw material system composed of cement-based powder phase, reinforcing phase, anhydrous liquid polymer compound, and anhydrous trace additives to produce a spinnable pulp. The extrusion feeder 2 is connected to both the pulping tank 1 and the fiber forming component 3, and is used to feed the spinnable pulp produced by the pulping tank 1. The material is conveyed to the fiber forming component 3; the fiber forming component 3 is used to form the spinnable slurry into fibrous streams and convey them to the non-aqueous coagulation bath 4; the non-aqueous coagulation bath 4 contains a non-aqueous coagulation medium, the non-aqueous coagulation bath 4 is used to solidify and shape the fibrous streams passing through it into nascent composite fibers, and convey the nascent composite fibers to the continuous drawing mechanism 5; the continuous drawing mechanism 5 is used to continuously draw and stretch the nascent composite fibers to modify them, and obtain cement-based composite fibers. This enables continuous production of cement-based composite fibers. The pulping tank 1 mixes the raw materials to obtain a spinnable pulp, while the extrusion feeder 2 and the fiber forming component 3 work together to form the spinnable pulp into fibrous streams. The non-aqueous coagulation bath 4 solidifies and shapes the fibrous streams (forming a polymer skeleton) and creates pores. The continuous drawing mechanism 5 continuously draws and stretches the nascent composite fibers, which helps improve the internal structure of the cement-based composite fibers and enhances their continuity and dimensional consistency. When the cement-based composite fibers are immersed in water, water quickly penetrates into the interior of the cement-based composite fibers through the interconnected porous channels, fully contacting the cement particles and undergoing a hydration reaction. The hydration products form a synergistic system with the polymer skeleton, thus giving the cement-based composite fibers both rigidity and toughness after immersion in water.

[0023] Hardware device introduction: like Figure 2 As shown, the pulping tank 1 in this embodiment includes a tank body 11 and a stirring component 12. The upper end of the tank body 11 is provided with a feed port 111, and the lower end of the tank body 11 is provided with a pulp outlet 112. The stirring component 12 is disposed on the tank body 11, and its stirring part is located inside the tank body 11. The stirring component 12 includes a drive component 121, a stirring shaft 122, and a shearing blade 123. The stirring shaft 122 is vertically arranged and passes through the tank body 11, and is rotatably connected to the tank body 11. The stirring shaft 122 is drively connected to the drive component 121 located outside the tank body 11. The shearing blade 123 is located inside the tank body 11 and is disposed on the stirring shaft 122. This design simplifies the structure of the entire stirring component 12, allows for thorough mixing of the raw material system, and forms a flowable spinnable pulp.

[0024] In this embodiment, two pulping tanks 1 can be set up, and the two pulping tanks 1 alternately prepare spinnable pulp, so that the entire cement-based composite fiber manufacturing equipment can maintain continuous production.

[0025] In this embodiment, two feeding ports 111 can be provided, one of which is used to feed solid materials, and the other is used to feed liquid materials.

[0026] In this embodiment, multiple shear blades 123 can be provided and evenly distributed on the stirring shaft 122.

[0027] like Figure 1 As shown, in this embodiment, the extrusion feeder 2 includes a feed pump 21, a flow meter 22, and a pressure equalization and flow stabilization container 23. The pulping tank 1, the feed pump 21, the pressure equalization and flow stabilization container 23, and the fiber forming component 3 are connected in sequence. The flow meter 22 is located at the connection between the feed pump 21 and the pressure equalization and flow stabilization container 23. The feed pump 21 is used to transport the spinnable pulp in the pulping tank 1 to the pressure equalization and flow stabilization container 23. The pressure equalization and flow stabilization container 23 is used to buffer the feed pressure of the spinnable pulp and supply it to the fiber forming component 3. This allows the flow rate of the spinnable slurry delivered by the feed pump 21 to be monitored by the flow meter 22. The spinnable slurry delivered by the feed pump 21 is then transferred to the fiberized forming part 3 after passing through the pressure equalization and flow stabilization container 23. This ensures that the feed pressure of the fiberized forming part 3 remains stable, which is beneficial to improving the stability of the speed during the continuous production of the cement-based composite fiber, thereby making the downstream components of the fiberized forming part 3 more compatible.

[0028] In this embodiment, the pressure equalization and flow stabilization container 23 is equivalent to a closed container, which can be connected to the feed pump 21 and the fiberized forming part 3 respectively.

[0029] like Figure 3 As shown, the fibrous forming part 3 in this embodiment includes a screw extruder 31 and a spinneret 32. The spinneret 32 ​​is located at the outlet end of the screw extruder 31, and the inlet end of the screw extruder 31 is connected to the extrusion feeder 2. This allows the spinnable slurry to be extruded into linear fibrous streams through the spinneret 32, and the fibrous streams can be further processed to obtain cement-based composite fibers.

[0030] like Figure 3As shown, in this embodiment, the non-aqueous coagulation bath 4 includes a coagulation bath 41 and a lower pressure roller 42. One end of the coagulation bath 41 has an inlet hole 411, which is connected to the spinneret 32. The lower pressure roller 42 is horizontally and rotatably mounted inside the coagulation bath 41. The coagulation bath 41 contains a non-aqueous coagulation medium. Both the lower pressure roller 42 and the inlet hole 411 are submerged below the surface of the non-aqueous coagulation medium. The fibrous stream is squeezed into the coagulation bath 41 through the inlet hole 411, then passes under the lower pressure roller 42 to immerse itself in the non-aqueous coagulation medium, and finally exits the coagulation bath 41. This allows the extruded fibrous stream to directly enter the coagulation bath 41 and contact the non-aqueous coagulation medium to obtain nascent composite fibers with a certain tensile toughness, which are then finally output.

[0031] In this embodiment, the lower pressure roller 42 is disposed at one end of the coagulation bath 41 away from the inlet hole 411.

[0032] like Figure 4 As shown, in this embodiment, a heating device 7 is further provided between the non-aqueous coagulation bath 4 and the continuous drawing mechanism 5. The non-aqueous coagulation medium is an anhydrous organic solvent (such as at least one of anhydrous ethanol, anhydrous isopropanol, anhydrous liquid paraffin, and white oil). The heating device 7 is used to heat the nascent composite fiber. In this way, the evaporation of the solvent in the nascent composite fiber can be accelerated by the heating device.

[0033] like Figure 4 As shown, the heating device 7 in this embodiment includes a housing 71 and a heating element 72 disposed within the housing 71. The housing 71 has aligned perforations 711 at both ends to allow the nascent composite fibers to pass through it. The housing 71 also has a negative pressure interface 712, which connects to the suction port of a negative pressure device. This allows for heating and drying of the nascent composite fibers while simultaneously enabling the solvent within the fibers to be more quickly precipitated and drained away due to the negative pressure. In this embodiment, the heating element can be an electric heating wire.

[0034] like Figure 3As shown, the continuous drawing mechanism 5 in this embodiment includes a vertical plate 51, a tension testing device 52, a counterweight roller 53, and at least two guide rollers 54. Multiple guide rollers 54 are spaced apart on the vertical plate 51 along the feeding direction of the nascent composite fiber. All guide rollers 54 are horizontally arranged, with one end vertically rotatably connected to the vertical plate 51. A counterweight roller 53 is vertically slidably connected to the vertical plate 51 below any two adjacent guide rollers 54, and the counterweight roller 53 is parallel to the guide rollers 54. The nascent composite fiber bends and passes sequentially around the counterweight roller 53 and guide roller 54. The tension testing device 52 is positioned between any guide roller 54 and the corresponding counterweight roller 53, with its sensing end contacting the corresponding part of the nascent composite fiber to measure the tension borne by the nascent composite fiber. In this way, the nascent composite fiber can be physically modified by the continuous stretching mechanism 5, thereby improving its toughness and making its dimensions more uniform. The tension testing device 52 can obtain the real-time tension value of the nascent composite fiber, which is equivalent to the magnitude of the traction force when it is stretched.

[0035] The installation form of the tension testing device 52 described in this embodiment can be similar to the tensioner body disclosed in document CN220766146U, "A Constant Tensioner for Feeding Covered Yarn".

[0036] In this embodiment, the nascent composite fiber has a “V”-shaped trajectory at each counterweight roller 53. It can be understood that the number of counterweight rollers 53 determines how many stages of traction and stretching the nascent composite fiber undergoes. For example, if there are only n counterweight rollers 53, the nascent composite fiber undergoes n stages of traction and stretching, where n is a positive integer, and n is usually any integer from 1 to 5.

[0037] like Figure 1 As shown, the cement-based composite fiber manufacturing equipment in this embodiment further includes a winding mechanism 6. The winding mechanism 6 is located on the side of the continuous drawing mechanism 5 away from the non-aqueous solidification bath 4, and is used to provide traction force to the cement-based composite fiber and wind it up. This allows the winding mechanism 6 to wind up the cement-based composite fiber and provide traction force to the cement-based composite fiber throughout the entire production process.

[0038] The winding mechanism 6 described in this embodiment is an existing device in the spinning field and will not be described in detail here.

[0039] Raw material system introduction: In this embodiment, the components of the raw material system, by mass fraction, are as follows: the cement-based powder phase content is 55-70 wt%, the reinforcing phase content is 1-5 wt%, the anhydrous trace additive content is 1-4 wt%, and the balance is anhydrous liquid polymer compound.

[0040] In this embodiment, the cement-based powder phase comprises a main binder and a binary system of SiO2-CaO. The main binder is at least one of ordinary Portland cement, rapid-hardening sulfoaluminate cement, and aluminate cement. Preferably, the main binder accounts for 90-95 wt% of the cement-based powder phase, and the SiO2-CaO binary system accounts for 5-10 wt% of the cement-based powder phase.

[0041] Ordinary silicate cement mainly provides stable late-stage hydration strength; rapid-hardening sulfoaluminate cement can provide faster early-stage strength; aluminate cement can improve early-stage strength and heat resistance. The three can be used alone or in combination to regulate the late-stage hydration rate, strength development, and service performance of cement-based composite fibers. The SiO2-CaO binary system can serve as an active inorganic regulating component. SiO2 can react with Ca(OH)2 generated later to produce pozzolanic reaction, generating more CSH gel. CaO or calcium-containing components can provide a calcium source to promote the formation of the late-stage inorganic cementitious phase. This system helps to improve the continuity of late-stage hydration products, pore filling effect, and strength of cement-based composite fibers.

[0042] In this embodiment, the reinforcing phase is at least one of whiskers and chopped fibers. The whiskers are at least one of calcium carbonate whiskers, calcium sulfate whiskers, zinc oxide whiskers, and silicon carbide whiskers, and the aspect ratio of the whiskers is 10-30. The chopped fibers are at least one of anhydrous polypropylene chopped fibers, polyimide chopped fibers, and basalt chopped fibers, and the length of the chopped fibers is 1-3 mm.

[0043] The anhydrous liquid polymer compound described in this embodiment is composed of a main liquid polymer, a co-crosslinking polymer, and a latent curing agent. The main liquid polymer is at least one of anhydrous polyethylene glycol, anhydrous liquid acrylate oligomer, and anhydrous liquid polybutadiene. The co-crosslinking polymer is at least one of anhydrous liquid epoxy resin oligomer and anhydrous hydroxyl-terminated polyurethane prepolymer. The latent curing agent is at least one of anhydrous amine latent curing agent and anhydrous benzoyl peroxide latent curing agent.

[0044] Preferably, the anhydrous polyethylene glycol has a molecular weight of 200-400, which is relatively low and has good fluidity under normal conditions, making it suitable as a liquid polymer component.

[0045] The main liquid polymer accounts for 70-85 wt% of the total anhydrous liquid polymer composite, the auxiliary crosslinking polymer accounts for 15-30 wt% of the total anhydrous liquid polymer composite, and the latent curing agent accounts for 1-4 wt% of the total anhydrous liquid polymer composite.

[0046] In this system, the main liquid polymer, as the continuous phase, constitutes the majority of the polymer base liquid and is responsible for providing flowability, wettability, and dispersibility, making the slurry suitable for continuous transport and nozzle extrusion. Specifically, anhydrous polyethylene glycol, anhydrous liquid acrylate oligomers, and anhydrous liquid polybutadiene can be used as the main liquid polymer. Among them, acrylate oligomers are beneficial for subsequent free radical crosslinking and curing, liquid polybutadiene is beneficial for improving flexibility, and PEG can improve dispersion and extractable pore-forming effects. The co-crosslinking polymer is used to provide crosslinking sites, enabling the liquid polymer to... In the coagulation bath, the flowable slurry is transformed into a stable skeleton. Specifically, anhydrous liquid epoxy resin oligomers can improve the strength and interfacial adhesion after curing; anhydrous hydroxyl-terminated polyurethane prepolymers can improve fiber flexibility and bending resistance; the key role of the latent curing agent is to control the reaction sequence. It remains relatively stable during the mixing, conveying and extrusion stages at room temperature, avoiding premature gelation or blockage of the spinneret 32. After entering the non-aqueous coagulation bath stage, the reaction is triggered or accelerated, causing the main liquid polymer and the auxiliary crosslinking polymer to crosslink and cure, forming a three-dimensional tough skeleton.

[0047] In this embodiment, the anhydrous trace additive is at least one of anhydrous polycarboxylate superplasticizer powder, anhydrous glyceryl stearate, anhydrous silicone defoamer, and anhydrous fumed silica. Specifically, anhydrous polycarboxylate superplasticizer powder can improve cement powder dispersion; anhydrous glyceryl stearate can improve lubricity and interfacial compatibility; anhydrous silicone defoamer can reduce bubbles generated during high-shear mixing; and anhydrous fumed silica can adjust the thixotropy of the slurry, prevent particle sedimentation, and enhance slurry stability.

[0048] The characteristics of preparing cement-based composite fibers in this embodiment are as follows: no free water is introduced throughout the process, so that the cement-based powder phase and the reinforcing phase are only dispersed and embedded as powder without pre-hydration; during the extrusion stage, the fluidity and spinnability of the slurry are provided by the completely anhydrous liquid polymer compound, and the extraction and shaping, phase separation and pore formation and cross-linking curing are achieved through a non-aqueous coagulation bath, so that the nascent composite fiber has certain toughness and tensile properties to meet the needs of subsequent production; and during the use stage, after the cement-based composite fiber comes into contact with water, the internal cement-based powder phase and the reinforcing phase undergo a hydration reaction, thereby forming cement hydration products, which improves the strength and structural stability of the cement-based composite fiber.

[0049] The role of each component in the raw material system is explained in this embodiment: Cement-based powder phase is the main source of later hydration hardening and inorganic skeleton formation. During the preparation stage of cement-based composite fibers, the cement-based powder phase does not undergo hydration and is only dispersed as solid particles in the completely anhydrous liquid polymer compound. In the later use or water-contaminated stage, the cement-based powder phase undergoes a hydration reaction to generate hydration products such as hydrated calcium silicate gel and ettringite, thereby improving the mechanical strength, dimensional stability and durability of cement-based composite fibers.

[0050] Reinforcing phases are mainly used to improve the brittleness of cement-based fibers. Whisker-type reinforcing phases can inhibit microcrack propagation through mechanisms such as crack bridging, crack deflection, and pull-out energy dissipation; chopped fiber-type reinforcing phases can play a bridging, tensile, bending, and toughening role on a larger scale, thereby improving the toughness, impact resistance, and structural integrity of composite fibers during continuous drawing.

[0051] The anhydrous liquid polymer compound is the continuous liquid phase and forming matrix in the preparation stage of cement-based composite fibers. Its main function is to wet and disperse the cement-based powder phase and the reinforcing phase, and to provide the slurry with fluidity, viscoelasticity and extrusion spinning properties. When entering the non-aqueous coagulation bath stage, the anhydrous liquid polymer compound forms an insoluble and infusible three-dimensional tough skeleton through extraction, phase separation and cross-linking triggered by a latent curing agent, embedding the cement-based powder phase and the reinforcing phase inside the three-dimensional tough skeleton.

[0052] Anhydrous trace additives are mainly used to improve the stability of slurry processing.

[0053] The non-aqueous coagulation bath medium is the core shaping system in this embodiment. Its function is to extract the extractable components in the anhydrous liquid polymer compound, thus initially shaping the extruded fibrous stream; inducing phase separation to form a through-porous structure; and simultaneously triggering or promoting the reaction of the latent curing agent, causing the polymer system to cross-link and solidify. The non-aqueous coagulation bath medium also does not introduce free water, avoiding prehydration of the cement-based powder phase.

[0054] In the following examples and comparative examples, unless otherwise stated, the content of each component is a mass percentage of the total mass of the raw material system; the distribution ratio of each component in the non-aqueous solidification medium is a volume ratio.

[0055] Example 1 This embodiment uses the cement-based composite fiber manufacturing equipment described above to produce cement-based composite fibers, and the specific details are as follows: In this embodiment, the components of the raw material system, by mass fraction, are as follows: the cement-based powder phase content is 60 wt%, the reinforcing phase content is 4 wt%, the anhydrous trace additive content is 2 wt%, and the anhydrous liquid polymer compound content is 34 wt%, totaling 100 wt%.

[0056] The composition of the cement-based powder phase, relative to the raw material system, by mass fraction, is as follows: 56 wt% ordinary Portland cement and 4 wt% SiO2-CaO binary system, totaling 60 wt%. The reinforcing phase is calcium sulfate whiskers; The composition of the anhydrous liquid polymer compound, relative to the raw material system, by mass fraction, is as follows: 28 wt% anhydrous polyethylene glycol, 5 wt% anhydrous liquid epoxy resin oligomer, and 1 wt% anhydrous amine latent curing agent, totaling 34 wt%. The composition of the anhydrous trace additives, relative to the raw material system, is as follows by mass fraction: 1 wt% anhydrous polycarboxylate superplasticizer and 1 wt% anhydrous silicone defoamer, totaling 2 wt%.

[0057] The cement-based powder phase and the reinforcing phase need to be pre-treated by drying in a vacuum oven before use (drying until the moisture content is less than 0.3wt%).

[0058] The preparation was carried out in a closed, dry environment with a relative humidity not exceeding 30%, and the steps are as follows: Step 1: Add the raw material system to the pulping tank 1 and stir for 20 minutes to obtain a uniformly dispersed spinnable sizing material; Step 2: The spinnable sizing material is fed to the fiberized forming part 3 through the extrusion feeder 2. The spinneret 32 ​​is a single hole with a diameter of 0.5 mm, and extrudes fibrous fine streams. Step 3: The fibrous stream is fed into a non-aqueous coagulation bath 4, which is a mixture of anhydrous ethanol and anhydrous isopropanol, to complete the initial shaping and cross-linking curing, so as to form nascent composite fibers; the volume ratio of anhydrous ethanol to anhydrous isopropanol is 1:1. Step 4: The nascent composite fibers are subjected to two-stage traction and stretching through the continuous stretching mechanism 5, and finally wound, collected, and stored in a moisture-proof and sealed manner.

[0059] The cement-based composite fiber prepared in this embodiment has a continuous and stable forming process, good fiber continuity, uniform appearance, and is not prone to fiber breakage during collection. The obtained cement-based composite fiber has a relatively stable polymer skeleton structure and porous structure, which facilitates subsequent moisture-proof storage and water hardening during use.

[0060] Example 2 Same as Example 1, but with the following differences: In this embodiment, the components of the raw material system, by mass fraction, are as follows: the cement-based powder phase content is 59 wt%, the reinforcing phase content is 5 wt%, the anhydrous trace additive content is 3 wt%, and the anhydrous liquid polymer compound content is 33 wt%, totaling 100 wt%.

[0061] The composition of the cement-based powder phase, relative to the raw material system, by mass fraction, is as follows: it consists of 54 wt% rapid-hardening sulfoaluminate cement and 4 wt% SiO2-CaO binary system, totaling 58 wt%. The reinforcing phase is chopped polypropylene fibers; The composition of the anhydrous liquid polymer compound, relative to the raw material system, by mass fraction, is as follows: 27 wt% anhydrous liquid acrylate oligomer, 5 wt% anhydrous hydroxyl-terminated polyurethane prepolymer, and 1 wt% anhydrous benzoyl peroxide latent curing agent, totaling 33 wt%. The composition of the anhydrous trace additive, relative to the raw material system, by mass fraction, is as follows: 1.5 wt% anhydrous fumed silica, 0.5 wt% anhydrous silicone defoamer, and 1 wt% anhydrous glyceryl stearate, totaling 3 wt%.

[0062] The preparation was carried out in a closed, dry environment with a relative humidity not exceeding 28%, and the steps are as follows: Step 1: Stirring time is 22 minutes; Step 2: The orifice diameter on the spinneret 32 ​​is 1 mm; Step 3: The fibrous stream is sent to the non-aqueous solidification bath 4, which is composed of anhydrous liquid paraffin and white oil, to complete the initial shaping and cross-linking curing; the volume ratio of anhydrous liquid paraffin to white oil is 1:1. Step 4: The nascent composite fibers are subjected to three-stage traction and stretching through the continuous stretching mechanism 5.

[0063] In this embodiment, short-cut fibers are used as the reinforcing phase. The resulting cement-based composite fibers exhibit small tension fluctuations and good stretching stability during continuous traction. The prepared cement-based composite fibers have relatively superior flexibility and are suitable for subsequent applications requiring a certain degree of bending adaptability.

[0064] Example 3 Same as Example 1, but with the following differences: In this embodiment, the components of the raw material system, by mass fraction, are as follows: the cement-based powder phase content is 62wt%, the reinforcing phase content is 3wt%, the anhydrous trace additive content is 4wt%, and the anhydrous liquid polymer compound content is 31wt%, totaling 100wt%.

[0065] The composition of the cement-based powder phase, relative to the raw material system, by mass fraction, is as follows: 58 wt% aluminate cement and 4 wt% SiO2-CaO binary system, totaling 62 wt%. The reinforcing phase is silicon carbide whiskers; The composition of the anhydrous liquid polymer compound, relative to the raw material system, by mass fraction, is as follows: 25 wt% anhydrous liquid polybutadiene, 5 wt% anhydrous liquid epoxy resin oligomer, and 1 wt% anhydrous amine latent curing agent, totaling 31 wt%. The composition of the anhydrous trace additives, in terms of mass fraction relative to the raw material system, is as follows: 2 wt% anhydrous polycarboxylate superplasticizer powder, 1 wt% anhydrous fumed silica, and 1 wt% anhydrous organosilicon defoamer, totaling 4 wt%.

[0066] The preparation was carried out in a closed, dry environment with a relative humidity not exceeding 25%, and the steps are as follows: Step 1: Stir for 18 minutes; Step 2: The spinneret 32 ​​is multi-hole; Step 3: The fibrous stream is sent to the non-aqueous curing bath 4, which is a non-aqueous curing medium of white oil, to complete the initial shaping and cross-linking curing.

[0067] In this embodiment, multiple cement-based composite fibers can be produced simultaneously, which is suitable for the continuous preparation of fiber bundles; the resulting fiber bundles have good bundle formation and collection efficiency, making them suitable for large-scale continuous production.

[0068] Comparative Example 1 Similar to Example 1, the difference is that the preparation was carried out directly under conventional experimental conditions, and the cement-based powder phase and the reinforcing phase were not dried before use.

[0069] When the above process was used to prepare the cement-based powder phase, it was easily affected by the ambient humidity during mixing and transportation, resulting in decreased slurry stability and the occurrence of local agglomeration, increased viscosity fluctuations, and discontinuous extrusion. After entering the non-aqueous coagulation bath 4, the uniformity of the fibrous fine stream formation was poor, and the stability of continuous production was insufficient. The storage stability and subsequent use consistency of the obtained cement-based composite fiber were both affected.

[0070] This comparative example illustrates that pretreatment of raw materials and pulping under low humidity or anhydrous conditions plays an important role in preventing premature cement hydration, maintaining the stability of spinnable pulp, and achieving continuous extrusion molding.

[0071] Comparative Example 2 Similar to Example 1, the difference is that an aqueous coagulation medium is used instead of an anhydrous coagulation medium in the non-aqueous coagulation bath 4, and the aqueous coagulation medium is deionized water; at the same time, the latent curing agent is omitted in the completely anhydrous liquid polymer compound, and the corresponding mass of the omitted latent curing agent is added to the anhydrous polyethylene glycol.

[0072] Specifically, the composition of the anhydrous liquid polymer complex in Comparative Example 2, by mass fraction relative to the raw material system, is as follows: 29 wt% anhydrous polyethylene glycol and 5 wt% anhydrous liquid epoxy resin oligomer, totaling 34 wt%, without the addition of a latent curing agent.

[0073] When the above process was used to prepare the comparative example, the cement-based powder phase would undergo premature hydration after the fibrous streams entered the deionized water. At the same time, since no latent curing agent was added, the anhydrous liquid polymer composite was difficult to form a stable three-dimensional solidified skeleton. The initial shaping effect of the fibrous streams was poor, and the nascent composite fibers were prone to breakage, adhesion or structural collapse during continuous traction. The resulting cement-based composite fibers were difficult to store stably in a dry state for a long time, and were also not conducive to forming a more ideal porous structure.

[0074] This comparative example illustrates that using a non-aqueous coagulation medium combined with a latent curing agent to trigger crosslinking is a key condition for achieving stable shaping of nascent composite fibers, forming a polymer skeleton and porous structure, and ensuring subsequent continuous stretching and moisture-proof storage.

[0075] Summarize: As can be seen from the above embodiments and comparative examples, the method of triggering crosslinking in a low-humidity or waterless environment by using a non-aqueous coagulation bath and a latent curing agent plays an important role in maintaining the stability of spinnable slurry, achieving stable and continuous forming of cement-based composite fibers, and constructing polymer skeletons and porous structures.

[0076] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Those skilled in the art can readily implement the present invention based on the accompanying drawings and the above description. However, any modifications, alterations, or variations made by those skilled in the art without departing from the scope of the present invention, utilizing the disclosed technical content, are equivalent embodiments of the present invention. Furthermore, any modifications, alterations, or variations made to the above embodiments based on the essential technology of the present invention are still within the protection scope of the present invention.

Claims

1. A cement-based composite fiber manufacturing equipment, characterized in that, It includes a pulping tank (1), an extrusion feeder (2), a fiber forming component (3), a non-aqueous coagulation bath component (4), and a continuous drawing mechanism (5) arranged in sequence. The pulping tank (1) is used to mix the raw material system consisting of cement-based powder phase, reinforcing phase, anhydrous liquid polymer compound and anhydrous trace additives and make it into a spinnable pulp. The extrusion feeder (2) is connected to the pulping tank (1) and the fiber forming part (3) respectively. The extrusion feeder (2) is used to transport the spinnable pulp produced by the pulping tank (1) to the fiber forming part (3). The fibrous molding part (3) is used to form the spinnable slurry into fibrous streams and transport them to the non-aqueous coagulation bath (4). The non-aqueous coagulation bath (4) contains a non-aqueous coagulation medium. The non-aqueous coagulation bath (4) is used to solidify and shape the fibrous stream passing through it into nascent composite fibers and to transport the nascent composite fibers to the continuous drawing mechanism (5). The continuous drawing mechanism (5) is used to continuously draw and stretch the nascent composite fiber to modify it and obtain cement-based composite fiber.

2. The cement-based composite fiber manufacturing equipment according to claim 1, characterized in that, The raw material system satisfies at least one of the following conditions AE: A: The components of the raw material system, by mass fraction, are as follows: the content of the cement-based powder phase is 55-70 wt%, the content of the reinforcing phase is 1-5 wt%, the content of the anhydrous trace additives is 1-4 wt%, and the balance is anhydrous liquid polymer compound. B: The cement-based powder phase comprises a main binder and a SiO2-CaO binary system, wherein the main binder is at least one of ordinary Portland cement, rapid-hardening sulfoaluminate cement and aluminate cement; C: The reinforcing phase is at least one of whiskers and chopped fibers. The whiskers are at least one of calcium carbonate whiskers, calcium sulfate whiskers, zinc oxide whiskers, and silicon carbide whiskers, and the aspect ratio of the whiskers is 10-30. The chopped fibers are at least one of anhydrous polypropylene chopped fibers, polyimide chopped fibers, and basalt chopped fibers, and the length of the chopped fibers is 1-3 mm. D: The anhydrous liquid polymer compound is composed of a main liquid polymer, a co-crosslinking polymer, and a latent curing agent. The main liquid polymer is at least one of anhydrous polyethylene glycol, anhydrous liquid acrylate oligomer, and anhydrous liquid polybutadiene. The co-crosslinking polymer is at least one of anhydrous liquid epoxy resin oligomer and anhydrous hydroxyl-terminated polyurethane prepolymer. The latent curing agent is at least one of anhydrous amine latent curing agent and anhydrous benzoyl peroxide latent curing agent. E: The anhydrous trace additive is at least one of anhydrous polycarboxylate superplasticizer powder, anhydrous glyceryl stearate, anhydrous organosilicon defoamer, and anhydrous fumed silica.

3. The cement-based composite fiber manufacturing equipment according to claim 1, characterized in that, It also includes a winding mechanism (6), which is located on the side of the continuous drawing mechanism (5) away from the non-aqueous curing bath (4) for providing traction force to the cement-based composite fiber and winding it up.

4. The cement-based composite fiber manufacturing equipment according to claim 1, characterized in that, The pulping tank (1) includes a tank body (11) and a stirring component (12). The upper end of the tank body (11) is provided with a feeding port (111), and the lower end of the tank body (11) is provided with a pulp outlet (112). The stirring component (12) is disposed on the tank body (11), and its stirring part is located inside the tank body (11). The stirring component (12) includes a driving component (121), a stirring shaft (122), and a shearing blade (123). The stirring shaft (122) is vertically arranged and passes through the tank (11) and is rotatably connected to the tank (11). The stirring shaft (122) is connected to the driving component (121) located outside the tank (11). The shearing blade (123) is located inside the tank (11) and is arranged on the stirring shaft (122).

5. The cement-based composite fiber manufacturing equipment according to claim 1, characterized in that, The extrusion feeder (2) includes a feed pump (21), a flow meter (22), and a pressure equalization and flow stabilization container (23). The pulping tank (1), the feed pump (21), the pressure equalization and flow stabilization container (23), and the fiber forming part (3) are connected in sequence. The flow meter (22) is located at the connection between the feed pump (21) and the pressure equalization and flow stabilization container (23). The feed pump (21) is used to transport the spinnable pulp in the pulping tank (1) to the pressure equalization and flow stabilization container (23). The pressure equalization and flow stabilization container (23) is used to buffer the feed pressure of the spinnable pulp and supply it to the fiber forming part (3).

6. The cement-based composite fiber manufacturing equipment according to claim 1, characterized in that, The fiberized forming part (3) includes a screw extruder (31) and a spinneret (32). The spinneret (32) is located at the outlet end of the screw extruder (31), and the inlet end of the screw extruder (31) is connected to the extrusion feeder (2).

7. The cement-based composite fiber manufacturing equipment according to claim 6, characterized in that, The non-aqueous coagulation bath component (4) includes a coagulation bath tank (41) and a lower pressure roller (42). One end of the coagulation bath tank (41) is provided with an inlet hole (411), and the inlet hole (411) is connected to the spinneret (32). The lower pressure roller (42) is horizontally set and rotatably installed in the coagulation bath tank (41). The coagulation bath tank (41) contains a non-aqueous coagulation medium. The lower pressure roller (42) and the inlet hole (411) are both immersed below the liquid surface of the non-aqueous coagulation medium. The fibrous stream is squeezed into the coagulation bath tank (41) through the inlet hole (411), then passes under the lower pressure roller (42) to immerse in the non-aqueous coagulation medium, and finally discharged out of the coagulation bath tank (41).

8. The cement-based composite fiber manufacturing equipment according to claim 1, characterized in that, A heating device (7) is also provided between the non-aqueous coagulation bath (4) and the continuous stretching mechanism (5). The non-aqueous coagulation medium is an anhydrous organic solvent. The heating device (7) is used to heat the nascent composite fiber.

9. The cement-based composite fiber manufacturing equipment according to claim 8, characterized in that, The heating device (7) includes a housing (71) and a heating element (72) disposed in the housing (71). The two ends of the housing (71) are provided with mutually aligned perforations (711) for the nascent composite fiber to pass through the housing (71). The housing (71) is provided with a negative pressure interface (712) for communicating with the air intake of a negative pressure device.

10. The cement-based composite fiber manufacturing equipment according to any one of claims 1-9, characterized in that, The continuous drawing mechanism (5) includes a vertical plate (51), a tension testing device (52), a counterweight roller (53), and at least two guide rollers (54). Multiple guide rollers (54) are spaced apart on the vertical plate (51) along the feeding direction of the nascent composite fiber. All guide rollers (54) are horizontally arranged, and one end of each guide roller is vertically rotatably connected to the vertical plate (51). A counterweight roller (53) is arranged below any two adjacent guide rollers (54) and is vertically slidably connected to the vertical plate (51). The counterweight roller (53) is parallel to the guide roller (54). The nascent composite fiber is bent and passes around the counterweight roller (53) and the guide roller (54) in sequence. The tension testing device (52) is arranged between any one of the guide rollers (54) and the corresponding counterweight roller (53), and its sensing end contacts the corresponding part of the nascent composite fiber to measure the tension of the nascent composite fiber.

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