Low-temperature tough CPVC (chlorinated polyvinyl chloride) power conduit and preparation method thereof
By adding carbon fiber, sepiolite, and nano-calcium carbonate-hydrogenated nitrile rubber composite particles to CPVC power pipes, the problem of poor toughness of CPVC power pipes at low temperatures was solved, achieving high toughness and impact resistance in low-temperature environments.
Patent Information
- Application Number
- CN202511782185.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-29
- Publication Date
- 2026-02-27
AI Technical Summary
Existing CPVC power pipes have poor toughness and are prone to brittleness in low-temperature environments, affecting loading, unloading, transportation and laying processes.
The pipe material is made by combining CPVC resin with PVC resin, heat stabilizers, composite lubricants, antioxidants and colorants, and adding carbon fiber, sepiolite and nano-calcium carbonate-hydrogenated nitrile rubber composite particles to improve the toughness and rigidity of the pipe through synergistic effect.
In low-temperature environments, CPVC pipes exhibit good toughness and impact resistance, preventing them from becoming brittle and cracking, and are suitable for cold working conditions.
Abstract
Description
Technical Field
[0001] This invention relates to the field of power cable conduits, and in particular to a low-temperature toughness CPVC power conduit and its preparation method. Background Technology
[0002] CPVC (chlorinated polyvinyl chloride) power conduit is a type of protective conduit for power cables made primarily from chlorinated polyvinyl chloride resin. It possesses excellent high-temperature resistance, corrosion resistance, and high compressive strength, while also being lightweight, flame-retardant, and easy to install. Therefore, it is widely used in power engineering, municipal construction, and other fields. During cable installation, CPVC conduit is fitted over the cable to protect it.
[0003] Existing CPVC power pipes have poor toughness, making them prone to damage during loading, unloading, transportation, and laying, especially in low-temperature environments where they are more likely to become brittle and crack. Summary of the Invention
[0004] In order to provide a CPVC power conduit with good toughness and low-temperature resistance, which can adapt to low-temperature environment operation, this application provides a low-temperature toughness CPVC power conduit and its preparation method.
[0005] This application provides a low-temperature toughness CPVC power conduit and its preparation method, which adopts the following technical solution: In a first aspect, this application provides a low-temperature toughness CPVC power conduit, which comprises the following raw materials in parts by weight: 75-85 parts of CPVC resin; 15-25 parts of PVC resin; Heat stabilizer 2-2.5 parts; 5-7 parts of compound lubricant; 6-9 parts impact modifier; 2-3.5 parts carbon fiber; 3-7 parts sepiolite; 7-11 parts of nano-calcium carbonate-hydrogenated nitrile rubber composite particles; Antioxidant 0.5-1 part; Colorant 0.8-1.4 parts.
[0006] By adopting the above technical solution, CPVC resin and PVC resin are used as basic components, combined with heat stabilizers, composite lubricants, antioxidants and colorants, etc., so that CPVC pipes have good processing performance and heat resistance. The addition of impact modifiers can improve the toughness and impact strength of the resin system.
[0007] Carbon fiber has high strength, high modulus, and excellent resistance to high and low temperatures. It can maintain a certain degree of flexibility at -180℃. When added to the resin matrix, it can act as a reinforcing filler to improve the rigidity and strength of CPVC pipes. At the same time, it can bridge cracks and hinder crack propagation at low temperatures.
[0008] Sepiolite, as a fibrous silicate clay mineral, can improve the modulus, strength, and dimensional stability of CPVC pipes. When subjected to impact, the pull-out and breakage of sepiolite fibers can effectively absorb energy, thereby improving low-temperature toughness.
[0009] Nano-calcium carbonate-hydrogenated nitrile rubber composite particles, as a complex of elastomer and rigid particles, can be uniformly dispersed in the resin system and form a certain flexible interface to transfer external stress. When subjected to damage, they induce silver crevice termination cracks and play a toughening role.
[0010] By adding carbon fiber, sepiolite, and nano-calcium carbonate-hydrogenated nitrile rubber composite particles, a synergistic effect can be achieved to form a multi-level reinforcing structure, realizing full-scale toughening from molecular chains to macro-fibers. At the same time, it improves the rigidity, pressure resistance, and thermal stability of CPVC pipes, enabling CPVC pipes to adapt to low-temperature environments without becoming brittle or cracking.
[0011] Optionally, the nano-calcium carbonate-hydrogenated nitrile rubber composite particles are prepared by the following steps: Nitrile latex was added to a three-necked flask, and hydrazine hydrate and a certain amount of distilled water were added while stirring. The temperature was raised to 50-55℃, and a mixture of boric acid, 30% hydrogen peroxide and distilled water was added dropwise to the three-necked flask. After the addition was completed, the temperature was raised to 75-80℃ and reacted for 1-1.5 hours. The temperature was raised to evaporate the distilled water, and hydrogenated nitrile latex was obtained. Nano-calcium carbonate slurry and sodium dodecyl sulfate were added to the reactor and stirred to obtain a stable nano-calcium carbonate suspension. The above-mentioned hydrogenated nitrile rubber latex and sodium stearate mixture was added to it, stirred and mixed, and heated to 85-88℃. After holding at this temperature for 20-30 min, a 10% (w / w) calcium chloride aqueous solution was added. Co-coagulation was carried out under stirring. After cooling to room temperature, the mixture was filtered, washed and dried to obtain nano-calcium carbonate-hydrogenated nitrile rubber composite particles.
[0012] By employing the above technical solution, hydrogenated nitrile butadiene rubber (NBR) latex is obtained through hydrogenation of NBR latex using the hydrazine hydrate method. The hydrogenated NBR exhibits superior cold resistance compared to standard NBR. The hydrogenation saturation of the carbon-carbon double bonds in the NBR molecular chain significantly enhances its resistance to UV aging and chemicals, making it more suitable for low-temperature environments. The elastomer can form an island structure within the resin matrix, and the core-shell composite particles exhibit higher interfacial compatibility with the resin matrix, achieving dual toughening.
[0013] Optionally, in the hydrogenated nitrile butadiene latex, the molar ratio of hydrazine hydrate, boric acid, hydrogen peroxide, and carbon-carbon double bonds in the nitrile butadiene latex is (1-1.5):(0.05-0.08):(1-1.2):1; the mass ratio of nano-calcium carbonate slurry to hydrogenated nitrile butadiene latex is (1-1.4):1; and the mass of sodium dodecyl sulfate, sodium stearate, and calcium chloride aqueous solution is 4%-6% of the hydrogenated nitrile butadiene latex.
[0014] By adopting the above technical solutions and adjusting the proportions of raw materials, hydrogenated nitrile rubber can be uniformly coated on the surface of nano-calcium carbonate.
[0015] Optionally, the sepiolite is selected from PMMA-grafted sepiolite, and is prepared through the following steps: Sepiolite was activated with dilute hydrochloric acid, filtered and dried to obtain pretreated sepiolite. The pretreated sepiolite was dispersed in anhydrous ethanol / water mixed solvent, and 1%-3% of KH-570 by mass of sepiolite was added to adjust the pH to 4-5. The reaction was stirred at 60-80℃ for 2-4 hours, filtered, washed and dried to obtain modified sepiolite. The modified sepiolite was added to MMA monomer, and potassium persulfate initiator was added dropwise. The mass ratio of modified sepiolite, MMA monomer and potassium persulfate was 1:(8-10):(0.04-0.1), and the dropwise addition time was 1-1.5 h. The mixture was heated to 75-80℃ under nitrogen protection and reacted for 4-6 h. After cooling, it was filtered, washed and dried to obtain PMMA-grafted sepiolite.
[0016] By adopting the above technical solutions, PMMA molecular chains are introduced onto the surface of sepiolite through free radical polymerization, which significantly improves the compatibility of sepiolite with organic polymers such as CPVC resin, and enhances its dispersibility and interfacial bonding in the resin matrix, thereby achieving a significant improvement in low-temperature toughness and rigidity.
[0017] Optionally, the heat stabilizer may be one or more of methyltin mercaptan, calcium zinc stabilizer, and calcium stearate.
[0018] Optionally, the composite lubricant is selected from two or more of the following: ethylene bis-stearamide, polyethylene wax, oxidized polyethylene wax, pentaerythritol tristearate, stearic acid, and glyceryl monostearate.
[0019] By adopting the above technical solutions and using a combination of internal and external lubricants, the processing performance of CPVC pipes can be improved.
[0020] Optionally, the impact modifier is selected from one or more of chlorinated polyethylene, ethylene vinyl acetate copolymer, acrylonitrile-butadiene-styrene copolymer, and methyl methacrylate-butadiene-styrene copolymer.
[0021] Optionally, the carbon fiber has a diameter of 7 μm and a length of 0.5-1 mm.
[0022] By adopting the above technical solutions, the dispersibility and compatibility of short-cut carbon fibers with the above parameters in the resin matrix are improved.
[0023] Optionally, the colorant may be selected from one of titanium dioxide, carbon black, phthalocyanine blue, phthalocyanine green, or cadmium red.
[0024] Secondly, this application provides a method for preparing a low-temperature toughness CPVC power conduit, comprising the following steps: S1: Mix CPVC resin, PVC resin, heat stabilizer, composite lubricant, impact modifier, carbon fiber, sepiolite, nano-calcium carbonate-hydrogenated nitrile rubber composite particles, antioxidant and colorant evenly, heat, extrude and granulate, and cool to obtain the mixture. S2: The mixture is extruded into a mold, cooled, cut, expanded, and packaged to obtain CPVC power conduit.
[0025] By adopting the above technical solutions, the preparation process is simple and suitable for large-scale production.
[0026] In summary, this application has at least one of the following beneficial effects: 1. CPVC resin and PVC resin are used as the basic components. Combined with heat stabilizers, composite lubricants, antioxidants and colorants, etc., CPVC pipes have good processing performance and heat resistance. The addition of impact modifiers can improve the toughness and impact strength of the resin system.
[0027] Carbon fiber has high strength, high modulus, and excellent resistance to high and low temperatures. It can maintain a certain degree of flexibility at -180℃. When added to the resin matrix, it can act as a reinforcing filler to improve the rigidity and strength of CPVC pipes. At the same time, it can bridge cracks and hinder crack propagation at low temperatures.
[0028] Sepiolite, as a fibrous silicate clay mineral, can improve the modulus, strength, and dimensional stability of CPVC pipes. When subjected to impact, the pull-out and breakage of sepiolite fibers can effectively absorb energy, thereby improving low-temperature toughness.
[0029] Nano-calcium carbonate-hydrogenated nitrile rubber composite particles, as a complex of elastomer and rigid particles, can be uniformly dispersed in the resin system and form a certain flexible interface to transfer external stress. When subjected to damage, they induce silver crevice termination cracks and play a toughening role.
[0030] By adding carbon fiber, sepiolite, and nano-calcium carbonate-hydrogenated nitrile rubber composite particles, a synergistic effect can be achieved to form a multi-level reinforcing structure, realizing full-scale toughening from molecular chains to macro-fibers. At the same time, it improves the rigidity, pressure resistance, and thermal stability of CPVC pipes, enabling CPVC pipes to adapt to low-temperature environments without becoming brittle or cracking.
[0031] 2. By introducing PMMA molecular chains onto the surface of sepiolite through free radical polymerization, the compatibility of sepiolite with organic polymers such as CPVC resin is significantly improved, and its dispersibility and interfacial bonding in the resin matrix are enhanced, resulting in a significant improvement in low-temperature toughness and rigidity. Detailed Implementation
[0032] The present application will be further described in detail below with reference to Examples 1-5 and Comparative Examples 1-4. Preparation Example
[0033] Preparation Example 1-1 Preparation of nano-calcium carbonate-hydrogenated nitrile rubber composite particles 100 ml of nitrile rubber latex containing carbon-carbon double bonds was added to a three-necked flask equipped with a constant pressure funnel and a condenser. While stirring, hydrazine hydrate and 30 ml of distilled water were added. The temperature was raised to 50°C. A mixture of boric acid, 30% hydrogen peroxide, and 40 ml of distilled water was added dropwise to the three-necked flask. After the addition was completed, the temperature was raised to 75°C and reacted for 1.5 h. The distilled water was evaporated by raising the temperature to obtain hydrogenated nitrile rubber latex. The molar ratio of carbon-carbon double bonds, hydrazine hydrate, boric acid, and hydrogen peroxide was 1:1:0.05:1. 100g of nano-calcium carbonate slurry and 4g of sodium dodecyl sulfate were added to a 3L jacketed reactor and stirred to obtain a stable nano-calcium carbonate suspension. Then, a mixture of 100g of hydrogenated nitrile rubber latex and 4g of sodium stearate was added to the suspension. The mixture was stirred and heated to 85℃ and kept at that temperature for 20min. Then, 4g of 10% calcium chloride aqueous solution was added and co-coagulated at a stirring rate of 380 r / min. After the system had completely coagulated, it was cooled to room temperature, filtered, washed and dried to obtain nano-calcium carbonate-hydrogenated nitrile rubber composite particles.
[0034] Preparation Examples 1-2 Preparation of nano-calcium carbonate-hydrogenated nitrile rubber composite particles 100 ml of nitrile rubber latex containing carbon-carbon double bonds was added to a three-necked flask equipped with a constant pressure funnel and a condenser. While stirring, hydrazine hydrate and 30 ml of distilled water were added. The temperature was raised to 55°C. A mixture of boric acid, 30% hydrogen peroxide, and 55 ml of distilled water was added dropwise to the three-necked flask. After the addition was completed, the temperature was raised to 80°C and reacted for 1 hour. The temperature was raised to evaporate the distilled water, and hydrogenated nitrile rubber latex was obtained. The molar ratio of carbon-carbon double bonds, hydrazine hydrate, boric acid, and hydrogen peroxide was 1:1.5:0.08:1.2. 140g of nano-calcium carbonate slurry and 6g of sodium dodecyl sulfate were added to a 3L jacketed reactor and stirred to obtain a stable nano-calcium carbonate suspension. Then, a mixture of 100g of hydrogenated nitrile rubber latex and 6g of sodium stearate was added to the suspension. The mixture was stirred and heated to 88℃ and kept at that temperature for 30min. Then, 6g of 10% calcium chloride aqueous solution was added and co-coagulated at a stirring rate of 400 r / min. After the system had completely coagulated, it was cooled to room temperature, filtered, washed and dried to obtain nano-calcium carbonate-hydrogenated nitrile rubber composite particles.
[0035] Preparation Example 2-1 Preparation of PMMA-grafted sepiolite Sepiolite was activated with 0.5 mol / L dilute hydrochloric acid for 2 h, filtered and dried to obtain pretreated sepiolite. The pretreated sepiolite was dispersed in anhydrous ethanol / water (volume ratio 95:5), and 1% KH-570 (by mass of sepiolite) was added. The pH was adjusted to 4-5 with acetic acid, and the reaction was stirred at 60 °C for 4 h. After filtration, washing and drying, modified sepiolite was obtained. The modified sepiolite was added to MMA monomer, and potassium persulfate initiator was added dropwise. The mass ratio of modified sepiolite, MMA monomer and potassium persulfate was 1:8:0.04, and the dropwise addition time was 1 h. The mixture was heated to 75 °C under nitrogen protection and reacted for 6 h. After cooling, it was filtered, washed and dried to obtain PMMA-grafted sepiolite.
[0036] Preparation Example 2-2 Preparation of PMMA-grafted sepiolite Sepiolite was activated with 15 mol / L dilute hydrochloric acid for 1 h, filtered and dried to obtain pretreated sepiolite. The pretreated sepiolite was dispersed in anhydrous ethanol / water (volume ratio 95:5), and 3% KH-570 (by mass of sepiolite) was added. The pH was adjusted to 4-5 with acetic acid, and the reaction was stirred at 80 °C for 2 h. After filtration, washing and drying, modified sepiolite was obtained. The modified sepiolite was added to MMA monomer, and potassium persulfate initiator was added dropwise. The mass ratio of modified sepiolite, MMA monomer and potassium persulfate was 1:10:0.1, and the dropwise addition time was 1.5 h. The mixture was heated to 80 °C under nitrogen protection and reacted for 4 h. After cooling, it was filtered, washed and dried to obtain PMMA-grafted sepiolite. Example
[0037] Example 1 This application provides a low-temperature toughness CPVC power conduit, comprising the following raw materials: 75 kg of CPVC resin, using CPVC resin with a chlorine content of 68%; 15kg of PVC resin, using SG-5 type PVC resin; 2 kg of heat stabilizer, methyltin mercaptan selected; 5 kg of composite stabilizer, specifically 3 kg of polyethylene wax as external lubricant and 2 kg of stearic acid as internal lubricant; 6 kg of impact modifier, specifically acrylonitrile-butadiene-styrene copolymer; 2 kg of carbon fiber, with a length of 0.5-1 mm and a diameter of 7 μm; 3 kg of sepiolite, with a particle size of 3-5 μm; 7 kg of nano-calcium carbonate-hydrogenated nitrile rubber composite particles were prepared using the composite particles obtained in Preparation Example 1-1. Antioxidant 0.5kg, antioxidant 1076 selected; Colorant 0.8kg, rutile titanium dioxide is selected.
[0038] The above-mentioned method for preparing a low-temperature toughness CPVC power conduit includes the following steps: S1: CPVC resin, PVC resin, heat stabilizer, composite lubricant, impact modifier, carbon fiber, sepiolite, nano-calcium carbonate-hydrogenated nitrile rubber composite particles, antioxidant and colorant are added to a high-speed mixer and stirred for 10 minutes to obtain a mixture. The mixture is then placed in a twin-screw extruder for heating and extrusion granulation. The temperature of each zone of the twin-screw extruder screw is 190-230℃, and the screw speed is 300r / min. After cooling, the mixture is obtained. S2: The mixture is extruded through a mold, cooled, cut, expanded, and packaged to obtain CPVC power conduit.
[0039] Example 2 This application provides a low-temperature toughness CPVC power conduit, comprising the following raw materials: 85 kg of CPVC resin, using CPVC resin with a chlorine content of 63%; 25kg of PVC resin, using SG-5 type PVC resin; 2.5 kg of heat stabilizer, calcium-zinc stabilizer is selected; 7 kg of composite stabilizer, specifically 4 kg of oxidized polyethylene wax as external lubricant and 3 kg of pentaerythritol tristearate as internal lubricant. 9 kg of impact modifier, specifically 5 kg of ethylene vinyl acetate copolymer and 4 kg of chlorinated polyethylene; 3.5 kg of carbon fiber, with a length of 0.5-1 mm and a diameter of 7 μm; 7 kg of sepiolite, with a particle size of 3-5 μm; 11 kg of nano-calcium carbonate-hydrogenated nitrile rubber composite particles were prepared using the composite particles obtained in Preparation Example 1-1. For every 1 kg of antioxidant, 0.5 kg of antioxidant 1076 and 0.5 kg of antioxidant 1010 are selected. 1.4 kg of colorant, carbon black is selected.
[0040] The preparation method of the low-temperature toughness CPVC power conduit described above is the same as that in Example 1.
[0041] Example 3 This application provides a low-temperature toughness CPVC power conduit, comprising the following raw materials: 78 kg of CPVC resin, using CPVC resin with a chlorine content of 68%; 23kg of PVC resin, SG-3 type PVC resin is selected; 2.3 kg of heat stabilizer, calcium stearate is selected; 6 kg of composite stabilizer, specifically 3 kg of ethylene bis-stearamide as external lubricant and 3 kg of glyceryl monostearate as internal lubricant; 7 kg of impact modifier, specifically methyl methacrylate-butadiene-styrene copolymer; 2.9 kg of carbon fiber, with a length of 0.5-1 mm and a diameter of 7 μm; 5 kg of sepiolite, with a particle size of 3-5 μm; 9 kg of nano-calcium carbonate-hydrogenated nitrile rubber composite particles were prepared using the composite particles obtained in Preparation Examples 1-2. Antioxidant 0.8kg, antioxidant 1010 selected; 1.2 kg of colorant, phthalocyanine green was selected.
[0042] The preparation method of the low-temperature toughness CPVC power conduit described above is the same as that in Example 1.
[0043] Example 4 The difference between this embodiment and Embodiment 1 is that the sepiolite in the raw material of CPVC electrical conduit is different.
[0044] In this embodiment, the sepiolite used is the PMMA-grafted sepiolite prepared in Preparation Example 2-1.
[0045] Example 5 The difference between this embodiment and Embodiment 1 is that the sepiolite in the raw material of CPVC electrical conduit is different.
[0046] In this embodiment, the sepiolite used is the PMMA-grafted sepiolite prepared in Preparation Example 2-2. Comparative Example
[0047] Comparative Example 1 The only difference between this comparative example and Example 1 is that no carbon fiber was added to the CPVC power conduit in this comparative example.
[0048] Comparative Example 2 The only difference between this comparative example and Example 1 is that sepiolite was not added to the CPVC electrical conduit in this comparative example.
[0049] Comparative Example 3 The only difference between this comparative example and Example 1 is that in this comparative example, an equal amount of nano-calcium carbonate is used instead of nano-calcium carbonate-hydrogenated nitrile rubber composite particles in the CPVC electrical conduit, i.e., 7 kg of nano-calcium carbonate.
[0050] Comparative Example 4 The only difference between this comparative example and Example 1 is that, in this comparative example, an equal amount of nano-calcium carbonate-nitrile rubber composite particles are used instead of nano-calcium carbonate-hydrogenated nitrile rubber composite particles in the CPVC electrical conduit, i.e., 7 kg of nano-calcium carbonate-nitrile rubber composite particles.
[0051] The preparation steps of nano-calcium carbonate-nitrile rubber composite particles are as follows: 140g of nano-calcium carbonate slurry and 6g of sodium dodecyl sulfate were added to a 3L jacketed reactor and stirred to obtain a stable nano-calcium carbonate suspension. Then, a mixture of 100g of nitrile rubber latex and 6g of sodium stearate was added to the suspension. The mixture was stirred and heated to 88℃ and kept at that temperature for 30min. Then, 6g of 10% calcium chloride aqueous solution was added and co-coagulated at a stirring rate of 400 r / min. After the system had completely coagulated, it was cooled to room temperature, filtered, washed and dried to obtain nano-calcium carbonate-nitrile rubber composite particles. Performance testing
[0052] The following performance tests were conducted on the CPVC power conduits prepared in the above embodiments and comparative examples.
[0053] 1. Ring stiffness test: The ring stiffness (kN / m) was tested according to GB / T 9647-2015 "Determination of Ring Stiffness of Thermoplastic Pipes". 2 ).
[0054] 2. Impact resistance test: A single-notch impact test was conducted according to method B, specimen type 6, of GB / T 18743.1-2022 "Determination of Impact Strength of Thermoplastic Pipes in Simply Supported Beams". The average test strength (kJ / m²) was recorded. 2 ).
[0055] 3. Cold Resistance Test: The CPVC samples obtained from each example and comparative example were treated in a low-temperature test chamber at -10℃ for 2 hours. The pipes were then subjected to impact testing using a drop hammer method. The hammer head weighed 12.5 kg and was dropped from a height of 2 meters. The pipes were observed for cracks and damage. A total of 10 samples were tested. The proportion of damaged samples to total samples was determined to obtain the true impact rate. A lower true impact rate indicates better low-temperature toughness and cold resistance of the material.
[0056] The table below shows the performance test results for each embodiment and comparative example.
[0057] Sample Ring stiffness Impact strength True Impact Rate Example 1 12.8 28.6 0 / 10 Example 2 13.2 28.2 0 / 10 Example 3 12.5 28.9 0 / 10 Example 4 14.7 31.2 0 / 10 Example 5 15.1 30.7 0 / 10 Comparative Example 1 8.5 23.4 3 / 10 Comparative Example 2 10.4 25.5 5 / 10 Comparative Example 3 10.1 24.6 6 / 10 Comparative Example 4 11.3 26.5 2 / 10 Based on the data in the table above, we can see that: 1. The CPVC power conduit prepared in this application has good rigidity and mechanical strength, excellent impact resistance, and good toughness even at low temperatures, making it suitable for construction operations in cold environments.
[0058] 2. When sepiolite is grafted with PMMA, the system compatibility is better, and sepiolite can be better dispersed in the resin matrix, thereby playing a toughening role and improving the toughness of the pipe at low temperature, thus improving the performance.
[0059] 3. Based on comparative examples 1-4, it can be seen that in this application, sepiolite, carbon fiber and nano-calcium carbonate-hydrogenated nitrile rubber composite particles work together to toughen and strengthen CPVC pipes. Through multi-scale and multi-level synergy of island structure + macro-bridge + micro-crack bridging, they work together to toughen and improve the strength, rigidity and cold resistance of CPVC power conduits.
[0060] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this specific embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.
Claims
1. A low-temperature toughness CPVC power conduit, characterized in that, The CPVC electrical conduit comprises the following raw materials in parts by weight: 75-85 parts of CPVC resin; 15-25 parts of PVC resin; Heat stabilizer 2-2.5 parts; 5-7 parts of compound lubricant; 6-9 parts impact modifier; 2-3.5 parts carbon fiber; 3-7 parts sepiolite; 7-11 parts of nano-calcium carbonate-hydrogenated nitrile rubber composite particles; Antioxidant 0.5-1 part; Colorant 0.8-1.4 parts.
2. The low-temperature toughness CPVC power conduit according to claim 1, characterized in that: The nano-calcium carbonate-hydrogenated nitrile rubber composite particles are prepared by the following steps: Nitrile latex was added to a three-necked flask, and hydrazine hydrate and a certain amount of distilled water were added while stirring. The temperature was raised to 50-55℃, and a mixture of boric acid, 30% hydrogen peroxide and distilled water was added dropwise to the three-necked flask. After the addition was completed, the temperature was raised to 75-80℃ and reacted for 1-1.5 hours. The temperature was raised to evaporate the distilled water, and hydrogenated nitrile latex was obtained. Nano-calcium carbonate slurry and sodium dodecyl sulfate were added to the reactor and stirred to obtain a stable nano-calcium carbonate suspension. The above-mentioned hydrogenated nitrile rubber latex and sodium stearate mixture was added to it, stirred and mixed, and heated to 85-88℃. After holding at this temperature for 20-30 min, a 10% (w / w) calcium chloride aqueous solution was added. Co-coagulation was carried out under stirring. After cooling to room temperature, the mixture was filtered, washed and dried to obtain nano-calcium carbonate-hydrogenated nitrile rubber composite particles.
3. The low-temperature toughness CPVC power conduit according to claim 2, characterized in that: In the hydrogenated nitrile butadiene latex, the molar ratio of hydrazine hydrate, boric acid, hydrogen peroxide, and carbon-carbon double bonds in the nitrile butadiene latex is (1-1.5):(0.05-0.08):(1-1.2):1; the mass ratio of nano-calcium carbonate slurry to hydrogenated nitrile butadiene latex is (1-1.4):1; and the mass of sodium dodecyl sulfate, sodium stearate, and calcium chloride aqueous solution is 4%-6% of the hydrogenated nitrile butadiene latex.
4. The low-temperature toughness CPVC power conduit according to claim 1, characterized in that: The sepiolite is selected from PMMA-grafted sepiolite and is prepared through the following steps: Sepiolite was activated with dilute hydrochloric acid, filtered and dried to obtain pretreated sepiolite. The pretreated sepiolite was dispersed in anhydrous ethanol / water mixed solvent, and 1%-3% of KH-570 by mass of sepiolite was added to adjust the pH to 4-5. The reaction was stirred at 60-80℃ for 2-4 hours, filtered, washed and dried to obtain modified sepiolite. The modified sepiolite was added to MMA monomer, and potassium persulfate initiator was added dropwise. The mass ratio of modified sepiolite, MMA monomer and potassium persulfate was 1:(8-10):(0.04-0.1), and the dropwise addition time was 1-1.5 h. The mixture was heated to 75-80℃ under nitrogen protection and reacted for 4-6 h. After cooling, it was filtered, washed and dried to obtain PMMA-grafted sepiolite.
5. The low-temperature toughness CPVC power conduit according to claim 1, characterized in that: The heat stabilizer is selected from one or more of thiol methyltin, calcium zinc stabilizer, and calcium stearate.
6. The low-temperature toughness CPVC power conduit according to claim 1, characterized in that: The composite lubricant is selected from two or more of the following: ethylene bis-stearamide, polyethylene wax, oxidized polyethylene wax, pentaerythritol tristearate, stearic acid, and glyceryl monostearate.
7. The low-temperature toughness CPVC power conduit according to claim 1, characterized in that: The impact modifier is selected from one or more of chlorinated polyethylene, ethylene vinyl acetate copolymer, acrylonitrile-butadiene-styrene copolymer, and methyl methacrylate-butadiene-styrene copolymer.
8. The low-temperature toughness CPVC power conduit according to claim 1, characterized in that: The carbon fiber has a diameter of 7 μm and a length of 0.5-1 mm.
9. The low-temperature toughness CPVC power conduit according to claim 1, characterized in that: The colorant is selected from one of titanium dioxide, carbon black, phthalocyanine blue, phthalocyanine green, or cadmium red.
10. A method for preparing a low-temperature toughness CPVC power conduit according to any one of claims 1-9, characterized in that, Includes the following steps: S1: Mix CPVC resin, PVC resin, heat stabilizer, composite lubricant, impact modifier, carbon fiber, sepiolite, nano-calcium carbonate-hydrogenated nitrile rubber composite particles, antioxidant and colorant evenly, heat, extrude and granulate, and cool to obtain the mixture. S2: The mixture is extruded into a mold, cooled, cut, expanded, and packaged to obtain CPVC power conduit.