Composite material for fire hose and preparation method thereof

Abstract

The invention relates to the technical field of composite material preparation, in particular to a composite material for a fire hose and a preparation method of the composite material. The preparation method of the composite material for the fire hose comprises the following steps: step A, adding the matrix resin, the reinforcing filler, the flexibilizer and the functional additive into a double-screw extruder, carrying out melt blending, and granulating to obtain an intermediate 1; and step B, adding the intermediate 1, a vulcanizing agent and a vulcanization accelerator into an internal mixer, pre-vulcanizing, transferring into a press vulcanizer, and carrying out pressurized vulcanization to obtain the composite material for the fire hose. The composite material for the fire hose has the advantages of favorable flame retardancy, stable mechanical properties, excellent tensile strength, elongation at break, aging resistance and wear resistance, and can still maintain favorable toughness in a low-temperature environment, so that the fire hose composite material can stably work under various extreme conditions due to the excellent comprehensive properties, and the service life of the fire hose is prolonged. The overall performance and the service life of the fire hose are improved.

Description

Technical Field

[0001] This application relates to the technical field of composite material preparation, and more specifically, it relates to a composite material for fire hoses and a preparation method thereof. Background Art

[0002] As a core equipment of the fire protection system, a fire hose is a flexible pipeline system used to transport high-pressure water, foam fire extinguishing agent or other liquid fire extinguishing media. Its core function is to undertake the key task of quickly and stably transporting the liquid fire extinguishing agent to the fire scene through a high-pressure-resistant and corrosion-resistant structural design, ensuring the efficiency and safety of fire fighting operations. This equipment is widely used in industrial fire protection, municipal rescue and special fire fighting and other fields, and its performance directly affects the success rate of fire rescue at the scene.

[0003] However, there are some problems with existing fire hose materials. For example, rubber hoses have good flexibility, but insufficient corrosion resistance and high-temperature resistance, and are prone to aging after long-term use, making it difficult to adapt to complex scenarios such as chemical industry and high temperature; polyvinyl chloride hoses have low cost, but poor pressure resistance, are prone to bursting, and have large low-temperature brittleness, unable to meet the requirements of high-pressure or cold environments; polyurethane hoses have advantages such as light weight and wear resistance, but high cost, which restricts their popularization and application; single fluororubber has high-temperature resistance, but insufficient flexibility, is prone to embrittlement at low temperatures, and has poor adhesion to the reinforcing layer; single polyvinylidene fluoride material has high hardness, so it has poor resistance to bending fatigue and is difficult to meet the dynamic use requirements. In view of the above defects, this application proposes a composite material for fire hoses with high-temperature resistance, acid and alkali corrosion resistance, high flexibility and high pressure resistance, which is suitable for scenarios such as high-pressure fire hoses and industrial hoses. Summary of the Invention

[0004] In order to solve the technical problems mentioned in the background art, this application provides a composite material for fire hoses and a preparation method thereof.

[0005] In the first aspect, this application provides a composite material for fire hoses, adopting the following technical scheme: A composite material for fire hoses, comprising the following raw materials in parts by weight: 40 - 60 parts of matrix resin, 2 - 4 parts of toughening agent, 5 - 8 parts of reinforcing filler, 4 - 6 parts of vulcanizing agent, 1 - 3 parts of vulcanization accelerator and 1 - 3 parts of functional additive.

[0006] Preferably, the matrix resin is composed of polyvinylidene fluoride, modified fluororubber and polyamide in a mass ratio of 10 - 15:5 - 8:1 - 3.

[0007] Preferably, the polyamide is aliphatic polyamide.

[0008] Preferably, the aliphatic polyamide is PA11 and / or PA12.

[0009] Preferably, the preparation method of the modified fluororubber comprises the following preparation steps: Step 1: Place the raw fluororubber on an open mill, at a temperature of 50 - 70 °C, thin-pass it 3 - 5 times, with the thin-pass roller gap being 0.5 - 1 mm, add a silane coupling agent with a mass fraction of 1 - 3%, and knead for 10 - 15 min to obtain a pretreated rubber compound; Step 2: Add the pretreated rubber compound, glycidyl methacrylate, dimethyl vinylphosphonate, and initiator to an internal mixer, under nitrogen protection, at a temperature of 160 - 180 °C, react for 1 - 2 h to obtain a grafted fluororubber; Step 3: Add the grafted fluororubber and thermoplastic polyurethane to a twin-screw extruder, melt-blend and extrude into pellets to obtain the modified fluororubber.

[0010] Preferably, in Step 2, the mass ratio of the pretreated rubber compound, glycidyl methacrylate, dimethyl vinylphosphonate, and initiator is 100 - 120:12 - 15:5 - 8:1 - 2.

[0011] Preferably, in Step 3, the mass of the thermoplastic polyurethane is 45 - 55% of the mass of the grafted fluororubber.

[0012] Preferably, the melt-blending temperature is 180 - 200 °C, the screw speed is 200 - 400 rpm, and the kneading time is 1 - 2 h.

[0013] Preferably, the toughening agent is composed of a styrene - ethylene - butene - styrene copolymer, polytetrafluoroethylene micropowder, and perfluoropolyether with a mass ratio of 12 - 18:4 - 7:3 - 5.

[0014] Preferably, the reinforcing filler is one or more of chopped carbon fiber, aramid fiber, and nano-silica.

[0015] Preferably, the vulcanizing agent is bisphenol AF; the vulcanization accelerator is benzyltriphenylphosphonium chloride.

[0016] Preferably, the functional auxiliary agent is one or more of a flame retardant, an anti-aging agent, an antistatic agent, and a lubricant.

[0017] In a second aspect, the present application also provides a preparation method of a composite material for a fire hose, comprising the following steps: Step A: Add the matrix resin, reinforcing filler, toughening agent, and functional auxiliary agent to a twin-screw extruder, After melt-blending, granulate to obtain Intermediate 1; Step B: Add intermediate 1, vulcanizing agent and vulcanization accelerator into an internal mixer, pre-vulcanize at a temperature of 150 - 180°C for 10 - 30 min, then transfer to a flat vulcanizing machine and carry out pressure vulcanization at a temperature of 180 - 200°C to obtain the composite material for fire hoses.

[0018] Preferably, the working conditions of the twin-screw extruder in Step A are as follows: the temperature of the feeding zone is 150 - 180°C, the temperature of the melting zone is 170 - 200°C, the temperature of the extrusion zone is 185 - 210°C, the screw speed is 200 - 400 rpm, and the mixing time is 1 - 2 h.

[0019] Preferably, in Step B, the pressure vulcanization pressure is 15 - 20 MPa and the vulcanization time is 30 - 45 min.

[0020] In summary, the present application has the following beneficial effects: The present application uses a matrix resin prepared by compounding polyvinylidene fluoride, modified fluororubber and aliphatic polyamide as the main material of the composite material for fire hoses. After the three are compounded, the high temperature resistance, corrosion resistance and mechanical properties of the composite material are significantly improved. Polyvinylidene fluoride can not only endow the material with high rigidity and tensile strength, but also improve the high temperature resistance, acid and alkali resistance and oil resistance of the material, and can resist corrosive media in fire fighting scenarios, such as fire extinguishing agents. By modifying the fluororubber, introducing flexible chain segments and graft modification, the elasticity and impact resistance of the material are enhanced. The selected aliphatic polyamide has excellent wear resistance and low temperature toughness, which can make up for the brittleness problem of polyvinylidene fluoride at low temperatures. After the three are compounded, through the synergistic effect of the rigid structure of polyvinylidene fluoride, the elasticity and processability optimization of fluororubber, and the low temperature toughness and wear resistance of aliphatic polyamide, combined with vulcanization crosslinking and carbon fiber reinforcement, the fire hose composite material has both high strength, flexibility, weather resistance and functional characteristics, meeting the strict requirements for the comprehensive performance of materials in the fire fighting field.

[0021] During the modification process of fluororubber in this application, the fluororubber is first pretreated with a silane coupling agent, and through calendering treatment, the molecular weight and cohesion of the fluororubber are reduced, and the processing fluidity is improved. Through graft copolymerization modification, functional groups are introduced. After glycidyl methacrylate grafting, epoxy groups are introduced, and dimethyl vinylphosphonate introduces phosphate ester groups, endowing the fluororubber with polarity and significantly improving its compatibility with polyvinylidene fluoride and polyamide. Through the initiation of free radical reactions by initiators, the chemical cross-linking between the fluororubber molecular chains is promoted. At the same time, the graft monomers act as bridges to form a three-dimensional network structure, improving the strength and high-temperature resistance of the material. The grafted fluororubber is blended with thermoplastic polyurethane, which can enhance the high elasticity and low-temperature toughness of the composite material. The fluororubber provides strength as the continuous phase, and the thermoplastic polyurethane absorbs impact energy as the dispersed phase, significantly improving the elongation at break and impact resistance. The fluororubber has been transformed from a single material with high hardness, difficult processing, and poor compatibility into a modified material with high toughness, easy processing, and high compatibility with polar resins, enabling it to exert the advantages of high temperature resistance and chemical resistance of fluororubber in fire hoses while making up for its brittleness defects.

[0022] In this application, a toughening agent is prepared by compounding styrene-ethylene-butene-styrene copolymer, polytetrafluoroethylene micropowder, and perfluoropolyether. Styrene-ethylene-butene-styrene copolymer is a thermoplastic elastomer with a two-phase structure of a rubber phase (ethylene-butene segment) and a plastic phase (styrene segment), which can form a dispersed phase in the matrix resin, significantly improving the elongation at break and impact strength of the composite material while maintaining a certain rigidity. The polytetrafluoroethylene micropowder has a small particle size and high hardness. As a rigid particle toughening agent, it consumes impact energy by inducing microcracks and plastic deformation in the matrix, while improving the wear resistance and surface smoothness of the material and reducing internal friction. The perfluoropolyether has an extremely low surface tension and excellent lubricity, improving the interfacial compatibility and promoting the uniform dispersion of the two phases. At the same time, it reduces the melt viscosity of polyvinylidene fluoride during the processing process, improves the fluidity, and avoids processing difficulties. Without significantly reducing the strength of the material, the flexibility, wear resistance, chemical resistance, and processing performance of the fire hose composite material are significantly improved. Detailed implementation mode

[0023] The following further elaborates on this application with reference to examples.

[0024] In the examples and comparative examples of this application, the polyvinylidene fluoride (grade: FR921-1) was purchased from Shanghai Sumei Polymer Materials Co., Ltd.; the fluororubber (grade: FKM88) was purchased from Aifudi'aimu (Anhui) New Materials Co., Ltd.; the PA11 (grade: BZMO 30) was purchased from Sabit Plastic Trade (Suzhou) Co., Ltd.; the styrene-ethylene-butene-styrene copolymer (grade: G1650M) was purchased from Dongguan Shengli New Materials Co., Ltd.; the polytetrafluoroethylene micropowder (grade: M111) was from Dongguan Zhongming Plastic Co., Ltd.; the perfluoropolyether (model: HT-200) was purchased from Shanghai Ruiyi Environmental Protection Technology Co., Ltd.; the short carbon fiber (8-10μm) was purchased from Changzhou Yaobang Friction Materials Factory; the bisphenol AF was purchased from Hubei Xinghengye Technology Co., Ltd.; the benzyltriphenylphosphonium chloride was purchased from Hubei Xinghengye Technology Co., Ltd.; the glycidyl methacrylate was purchased from Jinan Kaichuang Chemical Co., Ltd.; the dimethyl vinyl phosphonate was purchased from Hubei Keji Biomedical Technology Co., Ltd.; the thermoplastic polyurethane (grade: B90A11) was purchased from Dongguan Zhangmutou Lanqiao Plastic Raw Materials Business Department.

[0025] Examples 1-3 provide a composite material for fire hoses and a preparation method thereof.

[0026] Example 1 A composite material for fire hoses, comprising the following raw materials in parts by weight: 40 parts of matrix resin, 2 parts of toughening agent, 5 parts of reinforcing filler, 4 parts of vulcanizing agent, 1 part of vulcanization accelerator, and 1 part of functional additive. Among them, the matrix resin is composed of polyvinylidene fluoride, modified fluororubber, and polyamide with a mass ratio of 10:5:1, and the polyamide is PA11; the toughening agent is composed of styrene-ethylene-butene-styrene copolymer, polytetrafluoroethylene micropowder, and perfluoropolyether with a mass ratio of 12:4:3; the reinforcing filler is short carbon fiber; the vulcanizing agent is bisphenol AF; the vulcanization accelerator is benzyltriphenylphosphonium chloride; the functional additive is magnesium hydroxide.

[0027] Among them, the preparation method of the modified fluororubber includes the following preparation steps: Step 1: Place the fluororubber raw rubber on an open mill at a temperature of 50°C, thin-pass it 3 times, with a thin-pass roll gap of 0.5 mm, add 1% by mass of the silane coupling agent KH, and knead for 10 min at a kneading speed of 200 rpm to obtain a pretreated rubber compound; Step 2: Add the pretreated rubber compound, glycidyl methacrylate, dimethyl vinyl phosphonate, and dicumyl peroxide with a mass ratio of 100:12:5:1 to a kneader, and under nitrogen protection and at a temperature of 160°C, stir at a speed of 300 rpm and react for 1 h to obtain grafted fluororubber; Step 3: Add the grafted fluororubber and thermoplastic polyurethane into a twin-screw extruder, melt and blend them. The melt blending temperature is 180°C, the screw speed is 200 rpm, the mixing time is 1 h, and then extrude and pelletize to obtain the modified fluororubber. Among them, the mass of the thermoplastic polyurethane is 45% of the mass of the grafted fluororubber.

[0028] A preparation method of a composite material for a fire hose, comprising the following preparation steps: Step A: Add the matrix resin, reinforcing filler, toughening agent and functional additive into a twin-screw extruder, melt and blend them and then pelletize. Control the temperature of the feeding zone of the twin-screw extruder at 150°C, the temperature of the melting zone at 170°C, the temperature of the extrusion zone at 185°C, the screw speed at 200 rpm, and the mixing time at 1 h to obtain Intermediate 1; Step B: Add Intermediate 1, vulcanizing agent and vulcanization accelerator into a mixer, pre-vulcanize at 150°C for 10 min, transfer to a flat vulcanizer, and carry out pressure vulcanization at 180°C and a pressure of 15 MPa for 30 min to obtain the composite material for a fire hose.

[0029] Example 2 A composite material for a fire hose, comprising the following raw materials in parts by weight: 50 parts of matrix resin, 3 parts of toughening agent, 7 parts of reinforcing filler, 5 parts of vulcanizing agent, 2 parts of vulcanization accelerator and 2 parts of functional additive. Among them, the matrix resin is composed of polyvinylidene fluoride, modified fluororubber and polyamide with a mass ratio of 12:6:2. The polyamide is PA11. The toughening agent is composed of styrene-ethylene-butene-styrene copolymer, polytetrafluoroethylene micropowder and perfluoropolyether with a mass ratio of 15:6:4. The reinforcing filler is short carbon fiber. The vulcanizing agent is bisphenol AF. The vulcanization accelerator is benzyltriphenylphosphonium chloride. The functional additive is magnesium hydroxide.

[0030] Among them, the preparation method of the modified fluororubber comprises the following preparation steps: Step 1: Place the fluororubber raw rubber on an open mill, at a temperature of 60°C, thin pass 4 times, the gap of the thin pass roller is 0.8 mm, add 2% by mass of silane coupling agent KH-550, mix for 12 min, and the mixing speed is 400 rpm to obtain the pretreated rubber compound; Step 2: Add the pretreated rubber compound, glycidyl methacrylate, dimethyl vinyl phosphate and diisopropylbenzene peroxide with a mass ratio of 110:13:7:1.5 into a mixer, under nitrogen protection and at a temperature of 170°C, with a stirring speed of 400 rpm, react for 1.5 h to obtain the grafted fluororubber; Step 3: Add the grafted fluororubber and thermoplastic polyurethane into a twin-screw extruder, melt and blend them. The melt blending temperature is 190°C, the screw speed is 300 rpm, and the mixing time is 1.5 h. Then, extrude and pelletize to obtain the modified fluororubber. Among them, the mass of the thermoplastic polyurethane is 50% of the mass of the grafted fluororubber.

[0031] A preparation method of a composite material for a fire hose includes the following preparation steps: Step A: Add the matrix resin, reinforcing filler, toughening agent, and functional additive into a twin-screw extruder. After melt blending and pelletizing, control the temperature of the feeding zone of the twin-screw extruder at 165°C, the temperature of the melting zone at 185°C, the temperature of the extrusion zone at 195°C, the screw speed at 300 rpm, and the mixing time at 1.5 h to obtain Intermediate 1. Step B: Add Intermediate 1, vulcanizing agent, and vulcanization accelerator into a mixer. Pre-vulcanize for 20 min at a temperature of 165°C, then transfer it to a flat vulcanizer. Pressurize and vulcanize at a temperature of 190°C and a pressure of 18 MPa for 40 min to obtain the composite material for the fire hose.

[0032] Example 3 A composite material for a fire hose includes the following raw materials in parts by weight: 60 parts of matrix resin, 4 parts of toughening agent, 8 parts of reinforcing filler, 6 parts of vulcanizing agent, 3 parts of vulcanization accelerator, and 3 parts of functional additive. Among them, the matrix resin is composed of polyvinylidene fluoride, modified fluororubber, and polyamide with a mass ratio of 15:8:3. The polyamide is PA11. The toughening agent is composed of styrene-ethylene-butene-styrene copolymer, polytetrafluoroethylene micropowder, and perfluoropolyether with a mass ratio of 18:7:5. The reinforcing filler is short carbon fiber. The vulcanizing agent is bisphenol AF. The vulcanization accelerator is benzyltriphenylphosphonium chloride. The functional additive is magnesium hydroxide.

[0033] Among them, the preparation method of the modified fluororubber includes the following preparation steps: Step 1: Place the fluororubber raw rubber on an open mill, at a temperature of 70°C, thin pass 5 times, the gap of the thin pass roller is 1 mm, add 3% by mass of silane coupling agent KH-550, and mix for 15 min at a mixing speed of 500 rpm to obtain the pretreated rubber compound. Step 2: Add the pretreated rubber compound, glycidyl methacrylate, dimethyl vinyl phosphate, and diisopropylbenzene peroxide with a mass ratio of 120:15:8:2 into a mixer. Under nitrogen protection and at a temperature of 180°C, stir at a speed of 500 rpm for 2 h to obtain the grafted fluororubber. Step 3: Add the grafted fluororubber and thermoplastic polyurethane into a twin-screw extruder, melt and blend them. The melt blending temperature is 200 °C, the screw speed is 400 rpm, the mixing time is 2 h, and then extrude and pelletize to obtain the modified fluororubber. Among them, the mass of the thermoplastic polyurethane is 55% of the mass of the grafted fluororubber.

[0034] A preparation method of a composite material for a fire hose includes the following preparation steps: Step A: Add the matrix resin, reinforcing filler, toughening agent, and functional additive into a twin-screw extruder, melt and blend them and then pelletize. Control the temperature of the feeding zone of the twin-screw extruder to be 180 °C, the temperature of the melting zone to be 200 °C, the temperature of the extrusion zone to be 210 °C, the screw speed to be 400 rpm, and the mixing time to be 2 h to obtain Intermediate 1; Step B: Add Intermediate 1, vulcanizing agent, and vulcanization accelerator into a mixer. Pre-vulcanize at 180 °C for 30 min, then transfer to a flat vulcanizer, and carry out pressure vulcanization at 200 °C and a pressure of 20 MPa for 30 - 45 min to obtain the composite material for the fire hose.

[0035] Comparative Example 1 A composite material for a fire hose includes the following raw materials in parts by weight: 40 parts of matrix resin, 2 parts of toughening agent, 5 parts of reinforcing filler, 4 parts of vulcanizing agent, 1 part of vulcanization accelerator, and 1 part of functional additive. Among them, the matrix resin is composed of polyvinylidene fluoride, modified fluororubber, and polyamide with a mass ratio of 10:5:1, and the polyamide is PA11; the toughening agent is composed of styrene-ethylene-butene-styrene copolymer, polytetrafluoroethylene micropowder, and perfluoropolyether with a mass ratio of 12:4:3; the reinforcing filler is short carbon fiber; the vulcanizing agent is bisphenol AF; the vulcanization accelerator is benzyltriphenylphosphonium chloride; the functional additive is magnesium hydroxide.

[0036] Among them, the preparation method of the modified fluororubber includes the following preparation steps: Step 1: Place the fluororubber raw rubber on an open mill, at a temperature of 50 °C, thin-pass it 3 times, the gap of the thin-pass roller is 0.5 mm, add 1% by mass of the silane coupling agent KH, mix for 10 min, and the mixing speed is 200 rpm to obtain a pretreated rubber compound; Step 2: Add the pretreated rubber compound, dimethyl vinyl phosphate, and diisopropylbenzene peroxide with a mass ratio of 100:17:1 into a mixer, under nitrogen protection and at a temperature of 160 °C, with a stirring speed of 300 rpm, react for 1 h to obtain the grafted fluororubber; Step 3: Add the grafted fluororubber and thermoplastic polyurethane into a twin-screw extruder, melt and blend them. The melt blending temperature is 180°C, the screw speed is 200 rpm, and the mixing time is 1 h. Then, extrude and pelletize to obtain the modified fluororubber. Among them, the mass of thermoplastic polyurethane is 45% of the mass of the grafted fluororubber.

[0037] A preparation method of a composite material for a fire hose, comprising the following preparation steps: Step A: Add the matrix resin, reinforcing filler, toughening agent, and functional additive into a twin-screw extruder. After melt blending and pelletizing, control the temperature of the feeding zone of the twin-screw extruder to be 150°C, the temperature of the melting zone to be 170°C, the temperature of the extrusion zone to be 185°C, the screw speed to be 200 rpm, and the mixing time to be 1 h to obtain Intermediate 1. Step B: Add Intermediate 1, vulcanizing agent, and vulcanization accelerator into a kneader, pre-vulcanize at 150°C for 10 min, transfer to a flat vulcanizer, and carry out pressure vulcanization at 180°C and a pressure of 15 MPa for 30 min to obtain the composite material for the fire hose.

[0038] Comparative Example 2 A composite material for a fire hose, comprising the following raw materials in parts by weight: 40 parts of matrix resin, 2 parts of toughening agent, 5 parts of reinforcing filler, 4 parts of vulcanizing agent, 1 part of vulcanization accelerator, and 1 part of functional additive. Among them, the matrix resin is composed of polyvinylidene fluoride, modified fluororubber, and polyamide with a mass ratio of 10:5:1, and the polyamide is PA11; the toughening agent is composed of styrene-ethylene-butene-styrene copolymer, polytetrafluoroethylene micropowder, and perfluoropolyether with a mass ratio of 12:4:3; the reinforcing filler is short carbon fiber; the vulcanizing agent is bisphenol AF; the vulcanization accelerator is benzyltriphenylphosphonium chloride; the functional additive is magnesium hydroxide.

[0039] Among them, the preparation method of the modified fluororubber comprises the following preparation steps: Step 1: Place the fluororubber raw rubber on an open mill, at a temperature of 50°C, thin pass 3 times, the gap of the thin pass roller is 0.5 mm, add 1% by mass of silane coupling agent KH, mix for 10 min, and the mixing speed is 200 rpm to obtain a pretreated rubber compound. Step 2: Add the pretreated rubber compound, glycidyl methacrylate, and diisopropylbenzene peroxide with a mass ratio of 100:17:1 into a kneader, under nitrogen protection and at a temperature of 160°C, with a stirring speed of 300 rpm, react for 1 h to obtain the grafted fluororubber. Step 3: Add the grafted fluororubber and thermoplastic polyurethane into a twin-screw extruder, melt and blend them. The melt blending temperature is 180 °C, the screw speed is 200 rpm, the mixing time is 1 h, and then extrude and pelletize to obtain the modified fluororubber. Among them, the mass of the thermoplastic polyurethane is 45% of the mass of the grafted fluororubber.

[0040] A preparation method of a composite material for a fire hose includes the following preparation steps: Step A: Add the matrix resin, reinforcing filler, toughening agent and functional additive into a twin-screw extruder. After melt blending and pelletizing, control the feeding zone temperature of the twin-screw extruder at 150 °C, the melting zone temperature at 170 °C, the extrusion zone temperature at 185 °C, the screw speed at 200 rpm, and the mixing time at 1 h to obtain Intermediate 1. Step B: Add Intermediate 1, vulcanizing agent and vulcanization accelerator into a kneader, pre-vulcanize at 150 °C for 10 min, then transfer to a flat vulcanizer, and carry out pressure vulcanization at 180 °C and a pressure of 15 MPa for 30 min to obtain the composite material for a fire hose.

[0041] Comparative Example 3 A composite material for a fire hose includes the following raw materials in parts by weight: 40 parts of matrix resin, 2 parts of toughening agent, 5 parts of reinforcing filler, 4 parts of vulcanizing agent, 1 part of vulcanization accelerator and 1 part of functional additive. Among them, the matrix resin is composed of polyvinylidene fluoride, modified fluororubber and polyamide with a mass ratio of 10:5:1, and the polyamide is PA11; the toughening agent is composed of styrene-ethylene-butene-styrene copolymer, polytetrafluoroethylene micropowder and perfluoropolyether with a mass ratio of 12:4:3; the reinforcing filler is short carbon fiber; the vulcanizing agent is bisphenol AF; the vulcanization accelerator is benzyltriphenylphosphonium chloride; the functional additive is magnesium hydroxide.

[0042] Among them, the preparation method of the modified fluororubber includes the following preparation steps: Step 1: Place the fluororubber raw rubber on an open mill, at a temperature of 50 °C, thin pass it 3 times, the thin pass roll gap is 0.5 mm, add 1% by mass of silane coupling agent KH, mix for 10 min, and the mixing speed is 200 rpm to obtain a pretreated rubber compound. Step 2: Add the pretreated rubber compound, glycidyl methacrylate, dimethyl vinyl phosphate and diisopropylbenzene peroxide with a mass ratio of 100:12:5:1 into a kneader, under nitrogen protection and at a temperature of 160 °C, with a stirring speed of 300 rpm, react for 1 h to obtain the grafted fluororubber. Step 3: Add the grafted fluororubber and thermoplastic polyurethane into a twin-screw extruder, melt and blend them. The melt blending temperature is 180°C, the screw speed is 200 rpm, the mixing time is 1 h, and then extrude and pelletize to obtain the modified fluororubber. Among them, the mass of the thermoplastic polyurethane is 40% of the mass of the grafted fluororubber.

[0043] A preparation method of a composite material for a fire hose, comprising the following preparation steps: Step A: Add the matrix resin, reinforcing filler, toughening agent and functional additive into a twin-screw extruder. After melt blending and pelletizing, control the temperature of the feeding zone of the twin-screw extruder to be 150°C, the temperature of the melting zone to be 170°C, the temperature of the extrusion zone to be 185°C, the screw speed to be 200 rpm, and the mixing time to be 1 h to obtain Intermediate 1. Step B: Add Intermediate 1, vulcanizing agent and vulcanization accelerator into a mixer. Pre-vulcanize at a temperature of 150°C for 10 min, then transfer to a flat vulcanizer, and carry out pressure vulcanization at a temperature of 180°C and a pressure of 15 MPa for 30 min to obtain the composite material for the fire hose.

[0044] Comparative Example 4 A composite material for a fire hose, comprising the following raw materials in parts by weight: 40 parts of matrix resin, 2 parts of toughening agent, 5 parts of reinforcing filler, 4 parts of vulcanizing agent, 1 part of vulcanization accelerator and 1 part of functional additive. Among them, the matrix resin is composed of polyvinylidene fluoride, modified fluororubber and polyamide with a mass ratio of 10:5:1, and the polyamide is PA11; the toughening agent is composed of styrene-ethylene-butene-styrene copolymer, polytetrafluoroethylene micropowder and perfluoropolyether with a mass ratio of 12:4:3; the reinforcing filler is short carbon fiber; the vulcanizing agent is bisphenol AF; the vulcanization accelerator is benzyltriphenylphosphonium chloride; the functional additive is magnesium hydroxide.

[0045] Among them, the preparation method of the modified fluororubber comprises the following preparation steps: Step 1: Place the raw fluororubber on an open mill at a temperature of 50°C, thin-pass it 3 times, the gap of the thin-pass roller is 0.5 mm, add 1% by mass of the silane coupling agent KH, and mix for 10 min at a mixing speed of 200 rpm to obtain a pretreated rubber compound. Step 2: Add the pretreated rubber compound, glycidyl methacrylate, dimethyl vinyl phosphate and diisopropylbenzene peroxide with a mass ratio of 100:12:5:1 into a mixer. Under nitrogen protection and at a temperature of 160°C, stir at a speed of 300 rpm for 1 h to obtain the grafted fluororubber. Step 3: Add the grafted fluororubber and thermoplastic polyurethane into a twin-screw extruder, melt and blend them. The melt blending temperature is 180°C, the screw speed is 200 rpm, the mixing time is 1 h, and then extrude and pelletize to obtain the modified fluororubber. Among them, the mass of the thermoplastic polyurethane is 60% of the mass of the grafted fluororubber.

[0046] A preparation method of a composite material for a fire hose, comprising the following preparation steps: Step A: Add the matrix resin, reinforcing filler, toughening agent and functional additive into a twin-screw extruder, melt and blend them and then pelletize. Control the temperature of the feeding zone of the twin-screw extruder to be 150°C, the temperature of the melting zone to be 170°C, the temperature of the extrusion zone to be 185°C, the screw speed to be 200 rpm, and the mixing time to be 1 h to obtain Intermediate 1; Step B: Add Intermediate 1, vulcanizing agent and vulcanization accelerator into a kneader, pre-vulcanize at a temperature of 150°C for 10 min, transfer to a flat vulcanizer, and carry out pressure vulcanization at a temperature of 180°C and a pressure of 15 MPa for 30 min to obtain the composite material for a fire hose.

[0047] Comparative Example 5 A composite material for a fire hose, comprising the following raw materials in parts by weight: 40 parts of matrix resin, 2 parts of toughening agent, 5 parts of reinforcing filler, 4 parts of vulcanizing agent, 1 part of vulcanization accelerator and 1 part of functional additive. Among them, the matrix resin is composed of polyvinylidene fluoride, modified fluororubber and polyamide with a mass ratio of 10:5:1, and the polyamide is PA11; the toughening agent is composed of styrene-ethylene-butene-styrene copolymer and perfluoropolyether with a mass ratio of 4:1; the reinforcing filler is short carbon fiber; the vulcanizing agent is bisphenol AF; the vulcanization accelerator is benzyltriphenylphosphonium chloride; the functional additive is magnesium hydroxide.

[0048] Among them, the preparation method of the modified fluororubber comprises the following preparation steps: Step 1: Place the fluororubber raw rubber on an open mill, at a temperature of 50°C, thin pass it 3 times, the gap of the thin pass roller is 0.5 mm, add 1% by mass of silane coupling agent KH, and mix for 10 min, with a mixing speed of 200 rpm to obtain a pretreated rubber compound; Step 2: Add the pretreated rubber compound, glycidyl methacrylate, dimethyl vinyl phosphate and diisopropylbenzene peroxide with a mass ratio of 100:12:5:1 into a kneader, under nitrogen protection and at a temperature of 160°C, with a stirring speed of 300 rpm, react for 1 h to obtain the grafted fluororubber; Step 3: Add the grafted fluororubber and thermoplastic polyurethane into a twin-screw extruder, melt and blend them. The melt blending temperature is 180°C, the screw speed is 200 rpm, and the mixing time is 1 h. Then, extrude and pelletize to obtain the modified fluororubber. Among them, the mass of the thermoplastic polyurethane is 45% of the mass of the grafted fluororubber.

[0049] A preparation method of a composite material for a fire hose, comprising the following preparation steps: Step A: Add the matrix resin, reinforcing filler, toughening agent, and functional additive into a twin-screw extruder. After melt blending and pelletizing, control the feeding zone temperature of the twin-screw extruder at 150°C, the melting zone temperature at 170°C, the extrusion zone temperature at 185°C, the screw speed at 200 rpm, and the mixing time at 1 h to obtain Intermediate 1. Step B: Add Intermediate 1, vulcanizing agent, and vulcanization accelerator into a mixer. Pre-vulcanize at 150°C for 10 min, then transfer to a flat vulcanizer. Pressurize and vulcanize at 180°C and a pressure of 15 MPa for 30 min to obtain the composite material for a fire hose.

[0050] Comparative Example 6 A composite material for a fire hose, comprising the following raw materials in parts by weight: 40 parts of matrix resin, 2 parts of toughening agent, 5 parts of reinforcing filler, 4 parts of vulcanizing agent, 1 part of vulcanization accelerator, and 1 part of functional additive. Among them, the matrix resin is composed of polyvinylidene fluoride, modified fluororubber, and polyamide with a mass ratio of 10:5:1, and the polyamide is PA11; the toughening agent is composed of styrene-ethylene-butene-styrene copolymer and polytetrafluoroethylene micropowder with a mass ratio of 3:1; the reinforcing filler is short carbon fiber; the vulcanizing agent is bisphenol AF; the vulcanization accelerator is benzyltriphenylphosphonium chloride; the functional additive is magnesium hydroxide.

[0051] Among them, the preparation method of the modified fluororubber comprises the following preparation steps: Step 1: Place the fluororubber raw rubber on an open mill at 50°C, thin-pass it 3 times, with the thin-pass roll gap being 0.5 mm. Add 1% by mass of silane coupling agent KH and mix for 10 min at a mixing speed of 200 rpm to obtain a pretreated rubber compound. Step 2: Add the pretreated rubber compound, glycidyl methacrylate, dimethyl vinyl phosphate, and dicumyl peroxide with a mass ratio of 100:12:5:1 into a mixer. Under nitrogen protection and at a temperature of 160°C, stir at a speed of 300 rpm and react for 1 h to obtain the grafted fluororubber. Step 3: Add the grafted fluororubber and thermoplastic polyurethane into a twin-screw extruder, melt and blend them. The melt blending temperature is 180 °C, the screw speed is 200 rpm, the mixing time is 1 h, and then extrude and pelletize to obtain the modified fluororubber. Among them, the mass of the thermoplastic polyurethane is 45% of the mass of the grafted fluororubber.

[0052] A preparation method of a composite material for a fire hose, comprising the following preparation steps: Step A: Add the matrix resin, reinforcing filler, toughening agent and functional additive into a twin-screw extruder, melt and blend them and then pelletize. Control the temperature of the feeding zone of the twin-screw extruder to be 150 °C, the temperature of the melting zone to be 170 °C, the temperature of the extrusion zone to be 185 °C, the screw speed to be 200 rpm, and the mixing time to be 1 h to obtain Intermediate 1; Step B: Add Intermediate 1, vulcanizing agent and vulcanization accelerator into a mixer, pre-vulcanize at 150 °C for 10 min, transfer to a flat vulcanizer, and carry out pressure vulcanization at 180 °C and a pressure of 15 MPa for 30 min to obtain the composite material for the fire hose.

[0053] Performance Test Perform performance tests on the composite materials for fire hoses prepared in Examples 1-3 and Comparative Examples 1-6 as follows: Hardness: Test according to the national standard GB / T 531.1-2008 "Vulcanized Rubber or Thermoplastic Rubber - Test Method for Indentation Hardness - Part 1: Shore Hardness". Tensile Strength: Test according to the national standard GB / T 528-2009 "Vulcanized Rubber or Thermoplastic Rubber - Determination of Tensile Stress-Strain Properties", Type 1. Abrasion Resistance Test: Test according to the national standard GB / T 40797-2021 "Vulcanized Rubber or Thermoplastic Rubber - Determination of Abrasion Resistance - Vertical Drive Disk Method". The test is carried out using an RCC-1 type testing machine, with a rotation speed of 850 rpm, a striking frequency of 2.5 Hz, and a test time of 30 min. Aging Resistance Test: Test the elongation at break of the aged specimen according to the national standard GB / T 3512-2014 "Vulcanized Rubber or Thermoplastic Rubber - Heat Aging and Heat Resistance Tests". The aging conditions are 120 °C for 72 h. Low Temperature Brittleness: Test according to the national standard GB / T 1682-2014 "Determination of Low Temperature Brittleness of Vulcanized Rubber - Single Specimen Method". Limiting Oxygen Index Test: Test according to the national standard GB / T 2406.2-2009 "Plastics - Determination of Flammability by Oxygen Index - Part 2: Room Temperature Test". The test results are shown in Table 1.

[0054] Table 1 Performance parameters of the composite materials for fire hoses prepared in Examples 1-3 and Comparative Examples 1-6

[0055] As can be seen from Table 1, the composite material for fire hoses prepared in this application has good flame retardant properties, stable mechanical properties, excellent tensile strength and elongation at break. In addition, it also exhibits excellent aging resistance and wear resistance, and can still maintain good toughness in low temperature environments. This excellent comprehensive performance enables the fire hose composite material to work stably under various extreme conditions, improving the overall performance and service life of the fire hose.

[0056] This specific embodiment is only an interpretation of this application and does not limit this application. After reading this specification, those skilled in the art can make modifications to this embodiment without creative contributions as needed, but as long as it is within the scope of the claims of this application, it is protected by the patent law.

Claims

1. A composite material for a fire hose, characterized in that, It comprises raw materials in the following parts by weight: 40-60 parts of matrix resin, 2-4 parts of toughening agent, 5-8 parts of reinforcing filler, 4-6 parts of vulcanizing agent, 1-3 parts of vulcanization accelerator and 1-3 parts of functional additive.

2. The composite material for fire hoses according to claim 1, wherein, The matrix resin is composed of polyvinylidene fluoride, modified fluororubber and polyamide in a mass ratio of 10-15:5-8:1-3; the polyamide is aliphatic polyamide; the aliphatic polyamide is PA11 and / or PA12.

3. The composite material for fire hoses according to claim 2, characterized in that, The preparation method of the modified fluororubber comprises the following preparation steps: Step 1: Place the raw fluororubber on an open mill, at a temperature of 50-70 °C, thin-pass 3-5 times, the thin-pass roll gap is 0.5-1 mm, add a silane coupling agent with a mass fraction of 1-3%, and knead for 10-15 min to obtain a pretreated rubber compound. Step 2: Add the pretreated rubber compound, glycidyl methacrylate, dimethyl vinylphosphonate and initiator to an internal mixer, under nitrogen protection, at a temperature of 160-180 °C, react for 1-2 h to obtain grafted fluororubber. Step 3: Add the grafted fluororubber and thermoplastic polyurethane to a twin-screw extruder, melt-blend and extrude into pellets to obtain modified fluororubber.

4. The composite material for fire hoses according to claim 3, characterized in that, In Step 2, the mass ratio of the pretreated rubber compound, glycidyl methacrylate, dimethyl vinylphosphonate and initiator is 100-120:12-15:5-8:1-2.

5. The composite material for fire hoses according to claim 3, characterized in that, In Step 3, the mass of the thermoplastic polyurethane is 45-55% of the mass of the grafted fluororubber; the melt-blending temperature is 180-200 °C, the screw speed is 200-400 rpm, and the kneading time is 1-2 h.

6. The composite material for fire hoses according to claim 1, characterized in that, The toughening agent is composed of styrene-ethylene-butene-styrene copolymer, polytetrafluoroethylene micropowder and perfluoropolyether in a mass ratio of 12-18:4-7:3-5.

7. The composite material for fire hoses according to claim 1, characterized in that, The reinforcing filler is one or more of short carbon fibers, aramid fibers and nano-silica; the vulcanizing agent is bisphenol AF; the vulcanization accelerator is benzyltriphenylphosphonium chloride; the functional additive is one or more of a flame retardant, an anti-aging agent, an antistatic agent and a lubricant.

8. A method for preparing the composite material for fire hose according to any one of claims 1-7, characterized in that, It comprises the following preparation steps: Step A: Add the matrix resin, reinforcing filler, toughening agent and functional additive to a twin-screw extruder, After melt-blending, granulate to obtain Intermediate 1. Step B: Add Intermediate 1, vulcanizing agent and vulcanization accelerator to an internal mixer, pre-vulcanize at a temperature of 150-180 °C for 10-30 min, transfer to a flat vulcanizer, and carry out pressure vulcanization at a temperature of 180-200 °C to obtain the composite material for fire hoses.

9. The preparation method of the composite material for fire hoses according to claim 8, characterized in that, The working conditions of the twin-screw extruder in Step A are: the temperature of the feeding zone is 150-180 °C, the temperature of the melting zone is 170-200 °C, the temperature of the extrusion zone is 185-210 °C, the screw speed is 200-400 rpm, and the kneading time is 1-2 h.

10. The preparation method of the composite material for fire hoses according to claim 8, characterized in that, In Step B, the pressure vulcanization pressure is 15-20 MPa, and the vulcanization time is 30-45 min.

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