Low-temperature-resistant plastic alloy material and preparation method thereof

Abstract

The invention relates to the technical field of plastic alloy, in particular to a low-temperature-resistant plastic alloy material and a preparation method thereof. The low-temperature-resistant plastic alloy material is prepared from the following raw materials in parts by mass: 40 to 60 parts of polycarbonate, 20 to 40 parts of polyvinyl chloride, 1 to 2 parts of carboxyl-terminated polyamidoamine, 0.1 to 0.5 part of a silane coupling agent, 5 to 10 parts of tetraethoxysilane, 5 to 10 parts of nano montmorillonite, 1 to 5 parts of a toughening agent, 1 to 3 parts of a nucleating agent and 1 to 2 parts of an antioxidant. The obtained plastic alloy material has good tensile strength and bending strength, is not prone to cracking in the using process when applied to the sounding pipe, meanwhile, greatly improves the impact resistance of a product at the low temperature, improves the cold resistance of the product, and is excellent in stability when applied to the sounding pipe, and the reliability of the sounding pipe is enhanced.

Description

Technical Field

[0001] The present invention relates to the technical field of plastic alloys, and particularly relates to a low-temperature resistant plastic alloy material and a preparation method thereof. Background Art

[0002] Polycarbonate (PC) is an engineering plastic with a balance of rigidity and toughness, having characteristics such as high light transmittance, high refractive index, high impact resistance, and dimensional stability, and is widely used in the fields of electronic appliances, rail transit, and aerospace. However, due to its easy stress cracking and low temperature resistance, its scope of use is limited.

[0003] Polyvinyl chloride (PVC), on the other hand, is inexpensive and widely used. By adding different materials for compounding, new physical and mechanical properties can be presented. However, PVC materials have obvious disadvantages. Their thermal stability is poor and they are extremely prone to decomposition. The use value of unmodified PVC resin is relatively low, and the addition of plasticizers will also have a negative impact on the heat resistance of PVC materials, seriously affecting the operation safety, and greatly limiting the application of PVC.

[0004] In order to improve the performance of polycarbonate, compounding it with polyvinyl chloride to prepare a plastic alloy material with good low-temperature resistance, high impact strength, and not prone to cracking during use has become a technical problem to be solved urgently at present. Summary of the Invention

[0005] The purpose of the present invention is to solve the drawbacks existing in the prior art, and to provide a low-temperature resistant plastic alloy material and a preparation method thereof.

[0006] A low-temperature resistant plastic alloy material, the raw materials of which by mass include: 40 - 60 parts of polycarbonate, 20 - 40 parts of polyvinyl chloride, 1 - 2 parts of terminal carboxyl polyamidoamine, 0.1 - 0.5 parts of silane coupling agent, 5 - 10 parts of tetraethyl orthosilicate, 5 - 10 parts of nano-montmorillonite, 1 - 5 parts of toughening agent, 1 - 3 parts of nucleating agent, and 1 - 2 parts of antioxidant.

[0007] Preferably, the melt mass flow rate of polycarbonate is 10 - 40 g / 10 min under the conditions of 300 °C and 1.2 kg.

[0008] Preferably, the particle size of polyvinyl chloride is 100 - 500 μm.

[0009] Preferably, the silane coupling agent is an amino silane coupling agent, preferably 3-aminopropyltriethoxysilane.

[0010] Preferably, the toughening agent is at least one of methyl methacrylate-butadiene-styrene copolymer, methyl methacrylate-acrylic acid copolymer, and ethylene-butyl acrylate copolymer.

[0011] Preferably, the nucleating agent is at least one of talcum powder, calcium carbonate, and sodium carbonate.

[0012] Preferably, the antioxidant is 2,4 - di - tert - butylphenol.

[0013] The preparation method of the above - mentioned low - temperature resistant plastic alloy material comprises the following steps: S1. Add tetraethyl orthosilicate and silane coupling agent into an ethanol - aqueous solution, ultrasonically treat for 10 - 30 min, adjust the pH value of the system to 9 - 10 with ammonia water, add polyvinyl chloride, reflux and stir at 80 - 90 °C for 1 - 2 h, add terminal - carboxyl polyamidoamine and stir for 10 - 30 min, cool to room temperature, filter, wash, and vacuum - dry to obtain pretreated polyvinyl chloride; S2. Add nano - montmorillonite into isopropanol, ultrasonically treat for 1 - 2 h, add saturated ammonia water under stirring, reflux at 70 - 80 °C for 1 - 2 h, filter, wash, vacuum - dry, mix with the pretreated polyvinyl chloride, stir at 120 - 150 °C for 5 - 15 min, cool to room temperature, add polycarbonate, toughening agent, nucleating agent, and antioxidant and stir for 10 - 30 min to obtain a premix; S3. Extrude the premix, the extrusion temperature is 200 - 220 °C, perform biaxial stretching at 120 - 130 °C, and then cool.

[0014] Preferably, the ultrasonic frequency in S1 is 5 - 15 Hz.

[0015] Preferably, the ultrasonic frequency in S2 is 5 - 15 kHz.

[0016] Preferably, in S3, extrusion is carried out using a twin - screw extruder, and the screw speed is 100 - 150 r / min. Beneficial effects

[0017] The present invention can promote the good combination of nano - silica and polyvinyl chloride powder at the micro - nano scale. It can not only promote the self - plasticization of polyvinyl chloride during processing and reduce the use of plasticizers. The silanol groups formed by the hydrolysis of aminopropyltriethoxysilane on it interact with the surface carboxyl groups of terminal - carboxyl polyamidoamine to form covalent bonds, and not only form a winding structure with the molecular chains of polycarbonate. The compounding of the two can effectively prevent the expansion of internal cracks, effectively increase the tensile strength and flexural strength of the product, and it is not easy to crack during use. However, it is found through experiments that the low - temperature impact resistance of the product is poor at this time.

[0018] The present invention uses solvent stripping to exfoliate the lamellar structure of nano-montmorillonite, then treats it with concentrated ammonia water to promote surface activation, and then compound it with pretreated polyvinyl chloride powder. The active groups on it react with the carboxyl groups on the surface of the pretreated polyvinyl chloride powder to improve the plastic alloy material, which can effectively ensure the structural stability of the product in a low-temperature environment, exhibit good low-temperature resistance, and at the same time, the product has good ring stiffness and excellent pressure resistance performance. When applied to acoustic pipes, it has good affinity with concrete, is not easy to generate gaps with concrete, and has a low shrinkage rate.

[0019] The plastic alloy material obtained by the present invention has good tensile strength and flexural strength. When applied to acoustic pipes, it is not easy to crack during use, and at the same time, it greatly improves the impact resistance of the product at low temperature and enhances the cold resistance of the product. When used for acoustic pipes, it has excellent stability and enhances the reliability of the acoustic pipes.

[0020] The present invention optimizes the material formula production process and combines the biaxial stretching production process. When used for acoustic pipes, it has higher impact resistance and cold resistance, meets the construction requirements in a low-temperature environment, and has the characteristics of convenient use, light weight, and good connection sealing performance. It is an ideal substitute product for steel acoustic pipes. Description of the Drawings

[0021] Figure 1 It is a comparison chart of the tensile strength and flexural strength of the low-temperature resistant plastic alloy materials obtained in Example 5 and Comparative Examples 1-2.

[0022] Figure 2 It is a comparison chart of the room temperature cantilever beam notched impact strength and -40°C cantilever beam notched impact strength of the low-temperature resistant plastic alloy materials obtained in Example 5 and Comparative Examples 1-2.

[0023] Figure 3 It is a comparison chart of the shrinkage rate and ring stiffness of the tubular profiles obtained by biaxial stretching of the low-temperature resistant plastic alloy materials obtained in Example 5 and Comparative Examples 1-2. Detailed Embodiments

[0024] The present invention will be further explained below with reference to specific embodiments.

[0025] The polycarbonate was purchased from a certain Ward Chemical Co., Ltd. in Hubei, and its melt mass flow rate (300°C, 1.2 kg) was 8.0 g / 10 min. The polyvinyl chloride was purchased from a certain Tao Plastic Co., Ltd. in Dongguan, and the average particle size was 300 μm. Example 1

[0026] A low-temperature resistant plastic alloy material, the raw materials of which include: 40 g of polycarbonate, 20 g of polyvinyl chloride, 1 g of 2.0-generation carboxyl-terminated polyamidoamine, 0.1 g of aminopropyltriethoxysilane, 5 g of tetraethyl orthosilicate, 5 g of nanometer montmorillonite, 1 g of methyl methacrylate-butadiene-styrene copolymer, 1 g of talcum powder, and 1 g of 2,4-di-tert-butylphenol.

[0027] The preparation method of the above low-temperature resistant plastic alloy material includes the following steps: S1. Add tetraethyl orthosilicate and aminopropyltriethoxysilane to 15 g of an ethanol aqueous solution with a mass fraction of 40%, perform ultrasonic treatment for 10 min at an ultrasonic frequency of 5 Hz, adjust the pH value of the system to 9 - 10 with ammonia water, add polyvinyl chloride, reflux and stir at 80 °C for 1 h with a stirring speed of 100 r / min, add carboxyl-terminated polyamidoamine and stir for 10 min, cool to room temperature, filter, wash, and vacuum dry to obtain pretreated polyvinyl chloride; S2. Add nanometer montmorillonite to 20 g of isopropanol, perform ultrasonic treatment for 1 h at an ultrasonic frequency of 5 kHz, add 5 g of saturated ammonia water under stirring, reflux at 70 °C for 1 h, filter, wash, and vacuum dry, then send it together with the pretreated polyvinyl chloride into a high-speed mixer, stir at 120 °C for 5 min, cool to room temperature, add polycarbonate, methyl methacrylate-butadiene-styrene copolymer, talcum powder, and 2,4-di-tert-butylphenol and stir for 10 min with a stirring speed of 300 r / min to obtain a premix; S3. Send the premix into a twin-screw extruder for extrusion, control the screw speed at 100 r / min, the extrusion temperature at 200 °C, and cool. Example 2

[0028] A low-temperature resistant plastic alloy material, the raw materials of which include: 60 g of polycarbonate, 40 g of polyvinyl chloride, 2 g of 4.0-generation carboxyl-terminated polyamidoamine, 0.5 g of aminopropyltriethoxysilane, 10 g of tetraethyl orthosilicate, 10 g of nanometer montmorillonite, 5 g of methyl methacrylate-acrylic acid copolymer, 3 g of sodium carbonate, and 2 g of 2,4-di-tert-butylphenol.

[0029] The preparation method of the above low-temperature resistant plastic alloy material includes the following steps: S1. Add tetraethyl orthosilicate and aminopropyltriethoxysilane to 40 g of an ethanol aqueous solution with a mass fraction of 60%, perform ultrasonic treatment for 30 min at an ultrasonic frequency of 15 Hz, adjust the pH value of the system to 9 - 10 with ammonia water, add polyvinyl chloride, reflux and stir at 90 °C for 2 h with a stirring speed of 300 r / min, add carboxyl-terminated polyamidoamine and stir for 30 min, cool to room temperature, filter, wash, and vacuum dry to obtain pretreated polyvinyl chloride; S2. Add the nano-montmorillonite into 40 g of isopropanol and ultrasonically treat it for 2 h at an ultrasonic frequency of 15 kHz. While stirring, add 10 g of saturated ammonia water to it, reflux at 80 °C for 2 h, filter, wash, and vacuum dry. Then send it together with the pretreated polyvinyl chloride into a high-speed mixer, stir at 150 °C for 15 min, cool to room temperature, add polycarbonate, methyl methacrylate-acrylic acid copolymer, sodium carbonate, and 2,4-di-tert-butylphenol, and stir for 30 min at a stirring speed of 500 r / min to obtain a premix; S3. Send the premix into a twin-screw extruder for extrusion, control the screw speed at 150 r / min, and the extrusion temperature at 220 °C, and then cool. Example 3

[0030] A low-temperature resistant plastic alloy material, the raw materials of which include: 45 g of polycarbonate, 35 g of polyvinyl chloride, 1.7 g of 2.5-generation carboxyl-terminated polyamidoamine, 0.2 g of aminopropyltriethoxysilane, 9 g of tetraethyl orthosilicate, 7 g of nano-montmorillonite, 4 g of ethylene-butyl acrylate copolymer, 1.5 g of calcium carbonate, and 1.7 g of 2,4-di-tert-butylphenol.

[0031] The preparation method of the above low-temperature resistant plastic alloy material includes the following steps: S1. Add tetraethyl orthosilicate and aminopropyltriethoxysilane into 25 g of an ethanol aqueous solution with a mass fraction of 55% and ultrasonically treat it for 15 min at an ultrasonic frequency of 12 Hz. Adjust the pH value of the system to 9 - 10 with ammonia water, add polyvinyl chloride, reflux and stir at 82 °C for 100 min at a stirring speed of 150 r / min, add carboxyl-terminated polyamidoamine and stir for 25 min, cool to room temperature, filter, wash, and vacuum dry to obtain pretreated polyvinyl chloride; S2. Add the nano-montmorillonite into 25 g of isopropanol and ultrasonically treat it for 100 min at an ultrasonic frequency of 6 kHz. While stirring, add 9 g of saturated ammonia water to it, reflux at 73 °C for 100 min, filter, wash, and vacuum dry. Then send it together with the pretreated polyvinyl chloride into a high-speed mixer, stir at 130 °C for 12 min, cool to room temperature, add polycarbonate, ethylene-butyl acrylate copolymer, calcium carbonate, and 2,4-di-tert-butylphenol, and stir for 15 min at a stirring speed of 450 r / min to obtain a premix; S3. Send the premix into a twin-screw extruder for extrusion, control the screw speed at 110 r / min, and the extrusion temperature at 215 °C, and then cool. Example 4

[0032] A low-temperature resistant plastic alloy material, the raw materials of which include: 55 g of polycarbonate, 25 g of polyvinyl chloride, 1.3 g of 3.5-generation carboxyl-terminated polyamidoamine, 0.4 g of aminopropyltriethoxysilane, 7 g of tetraethyl orthosilicate, 9 g of nanometer montmorillonite, 2 g of methyl methacrylate-butadiene-styrene copolymer, 2.5 g of calcium carbonate, and 1.3 g of 2,4-di-tert-butylphenol.

[0033] The preparation method of the above low-temperature resistant plastic alloy material includes the following steps: S1. Add tetraethyl orthosilicate and aminopropyltriethoxysilane to 35 g of an ethanol aqueous solution with a mass fraction of 45%, perform ultrasonic treatment for 25 min, the ultrasonic frequency is 6 Hz, adjust the pH value of the system to 9-10 with ammonia water, add polyvinyl chloride, reflux and stir at 88 °C for 80 min, the stirring speed is 240 r / min, add carboxyl-terminated polyamidoamine and stir for 15 min, cool to room temperature, filter, wash, and vacuum dry to obtain pretreated polyvinyl chloride; S2. Add nanometer montmorillonite to 35 g of isopropanol, perform ultrasonic treatment for 80 min, the ultrasonic frequency is 12 kHz, add 7 g of saturated ammonia water thereto under stirring, reflux at 77 °C for 80 min, filter, wash, and vacuum dry, and send it together with the pretreated polyvinyl chloride into a high-speed mixer, stir at 140 °C for 8 min, cool to room temperature, add polycarbonate, methyl methacrylate-butadiene-styrene copolymer, calcium carbonate, and 2,4-di-tert-butylphenol and stir for 25 min, the stirring speed is 350 r / min, to obtain a premix; S3. Send the premix into a twin-screw extruder for extrusion, control the screw speed at 130 r / min, the extrusion temperature at 205 °C, and cool. Example 5

[0034] A low-temperature resistant plastic alloy material, the raw materials of which include: 50 g of polycarbonate, 30 g of polyvinyl chloride, 1.5 g of 3.0-generation carboxyl-terminated polyamidoamine, 0.3 g of aminopropyltriethoxysilane, 8 g of tetraethyl orthosilicate, 8 g of nanometer montmorillonite, 3 g of methyl methacrylate-acrylic acid copolymer, 2 g of calcium carbonate, and 1.5 g of 2,4-di-tert-butylphenol.

[0035] The preparation method of the above low-temperature resistant plastic alloy material includes the following steps: S1. Add tetraethyl orthosilicate and aminopropyltriethoxysilane to 30 g of an ethanol aqueous solution with a mass fraction of 50%, perform ultrasonic treatment for 20 min, the ultrasonic frequency is 9 Hz, adjust the pH value of the system to 9-10 with ammonia water, add polyvinyl chloride, reflux and stir at 85 °C for 90 min, the stirring speed is 200 r / min, add carboxyl-terminated polyamidoamine and stir for 20 min, cool to room temperature, filter, wash, and vacuum dry to obtain pretreated polyvinyl chloride; S2. Add the nano-montmorillonite to 30 g of isopropanol and ultrasonically treat it for 90 min at an ultrasonic frequency of 9 kHz. While stirring, add 8 g of saturated ammonia water to it, reflux at 75 °C for 90 min, filter, wash, and vacuum dry. Then send it together with the pretreated polyvinyl chloride into a high-speed mixer, stir at 135 °C for 10 min, cool to room temperature, add polycarbonate, methyl methacrylate-acrylic acid copolymer, calcium carbonate, and 2,4-di-tert-butylphenol and stir for 20 min at a stirring speed of 400 r / min to obtain a premix; S3. Send the premix into a twin-screw extruder for extrusion, control the screw speed at 120 r / min, and the extrusion temperature at 210 °C, and then cool.

[0036] Comparative Example 1 A low-temperature resistant plastic alloy material, the raw materials of which include: 50 g of polycarbonate, 30 g of polyvinyl chloride, 1.5 g of 3.0-generation carboxyl-terminated polyamidoamine, 0.3 g of aminopropyltriethoxysilane, 8 g of tetraethyl orthosilicate, 8 g of nano-montmorillonite, 3 g of methyl methacrylate-acrylic acid copolymer, 2 g of calcium carbonate, and 1.5 g of 2,4-di-tert-butylphenol.

[0037] The preparation method of the above low-temperature resistant plastic alloy material includes the following steps: S1. Add tetraethyl orthosilicate and aminopropyltriethoxysilane to 30 g of an ethanol aqueous solution with a mass fraction of 50% and ultrasonically treat it for 20 min at an ultrasonic frequency of 9 Hz. Use ammonia water to adjust the pH value of the system to 9-10, add polyvinyl chloride, reflux and stir at 85 °C for 90 min at a stirring speed of 200 r / min, cool to room temperature, filter, wash, and vacuum dry to obtain pretreated polyvinyl chloride; S2. Add the nano-montmorillonite to 30 g of isopropanol and ultrasonically treat it for 90 min at an ultrasonic frequency of 9 kHz. While stirring, add 8 g of saturated ammonia water to it, reflux at 75 °C for 90 min, filter, wash, and vacuum dry. Then send it together with the pretreated polyvinyl chloride into a high-speed mixer, stir at 135 °C for 10 min, cool to room temperature, add polycarbonate, carboxyl-terminated polyamidoamine, methyl methacrylate-acrylic acid copolymer, calcium carbonate, and 2,4-di-tert-butylphenol and stir for 20 min at a stirring speed of 400 r / min to obtain a premix; S3. Send the premix into a twin-screw extruder for extrusion, control the screw speed at 120 r / min, and the extrusion temperature at 210 °C, and then cool.

[0038] Comparative Example 2 A low-temperature resistant plastic alloy material, the raw materials of which include: 50 g of polycarbonate, 30 g of polyvinyl chloride, 1.5 g of 3.0-generation carboxyl-terminated polyamidoamine, 0.3 g of aminopropyltriethoxysilane, 8 g of tetraethyl orthosilicate, 8 g of nanometer montmorillonite, 3 g of methyl methacrylate-acrylic acid copolymer, 2 g of calcium carbonate, and 1.5 g of 2,4-di-tert-butylphenol.

[0039] The preparation method of the above low-temperature resistant plastic alloy material includes the following steps: S1. Add tetraethyl orthosilicate and aminopropyltriethoxysilane to 30 g of an ethanol aqueous solution with a mass fraction of 50%, perform ultrasonic treatment for 20 min, the ultrasonic frequency is 9 Hz, adjust the pH value of the system to 9 - 10 with ammonia water, add polyvinyl chloride, reflux and stir at 85°C for 90 min, the stirring speed is 200 r / min, add carboxyl-terminated polyamidoamine and stir for 20 min, cool to room temperature, filter, wash, and vacuum dry to obtain pretreated polyvinyl chloride; S2. Send nanometer montmorillonite and pretreated polyvinyl chloride into a high-speed mixer, stir at 135°C for 10 min, cool to room temperature, add polycarbonate, methyl methacrylate-acrylic acid copolymer, calcium carbonate, and 2,4-di-tert-butylphenol and stir for 20 min, the stirring speed is 400 r / min, to obtain a premix; S3. Send the premix into a twin-screw extruder for extrusion, control the screw speed at 120 r / min, the extrusion temperature at 210°C, and cool.

[0040] Make the low-temperature resistant plastic alloy materials obtained in Example 5 and Comparative Examples 1 - 2 into sheets, and then conduct mechanical property tests on each group of sheet specimens as follows: (1) Determine the tensile strength of each group of specimens with reference to GB / T 1040.2 - 2022 Plastics - Determination of tensile properties - Part 2: Test conditions for moulding and extrusion plastics; (2) Determine the flexural strength of each group of specimens with reference to GB / T 9341 - 2008 Plastics - Determination of flexural properties; (3) Determine the notched impact strength at normal temperature and low temperature (-40°C) of each group of specimens with reference to GB / T 1843 - 2008 Plastics - Determination of Izod impact strength.

[0041] As Figure 1 and Figure 2 shown, the sheets made of the premix obtained in Example 5 have the highest tensile strength, flexural strength, and impact strength, which are superior to those of Comparative Examples 1 - 2 (P < 0.05).

[0042] The low-temperature resistant plastic alloy materials obtained in Example 5 and Comparative Examples 1-2 were biaxially stretched at a temperature of 125 °C (the draw ratio was 1.5) to form tubular profiles (outer diameter 50 mm, wall thickness 2.5 mm, and the connection method was L-thread type), and the following performance tests were carried out: (1) Refer to GB / T 6671-2001 "Determination of longitudinal reversion rate of thermoplastic pipes" to determine the reversion rate of each group of specimens.

[0043] (2) Refer to GB / T 9647-2015 "Determination of ring stiffness of thermoplastic pipes" to determine the ring stiffness of each group of specimens.

[0044] As Figure 3 shown, the tubular profile obtained in Example 5 had the smallest reversion rate and the highest ring stiffness, which was superior to those of Comparative Examples 1-2 (P < 0.05).

[0045] The applicant believes that the reason for the above results is as follows: The present invention can promote the good combination of nano-silica and polyvinyl chloride powder at the micro-nano scale, which can not only promote the self-plasticization of polyvinyl chloride during processing and reduce the use of plasticizers, but also the silanol groups formed by the hydrolysis of aminopropyltriethoxysilane on it interact with the surface carboxyl groups of the terminal carboxyl polyamidoamine to form covalent bonds, which not only form an entangled structure with the polycarbonate molecular chain, and the compounding of the two can effectively prevent the expansion of internal cracks, effectively increase the tensile strength and bending strength of the product, and it is not easy to crack during use; The present invention also uses solvent peeling to exfoliate the nano-montmorillonite lamellar structure, then uses concentrated ammonia water treatment to promote surface activation, and then compound it with the pretreated polyvinyl chloride powder. The active groups on it react with the surface carboxyl groups of the pretreated polyvinyl chloride powder to improve the plastic alloy material, which can effectively ensure the structural stability of the product in a low-temperature environment, show good low-temperature resistance, and at the same time the product has good ring stiffness and excellent pressure resistance performance. When applied to a sonic logging tube, it has a good affinity with concrete, is not easy to generate gaps with concrete, and has a low reversion rate.

[0046] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution of the present invention and its inventive concept, makes equivalent substitutions or changes, and should be covered by the protection scope of the present invention.

Claims

1. A low temperature resistant plastic alloy material, characterized in that: The raw materials include, by mass, 40-60 parts of polycarbonate, 20-40 parts of polyvinyl chloride, 1-2 parts of carboxyl-terminated polyamide amine, 0.1-0.5 parts of silane coupling agent, 5-10 parts of tetraethyl orthosilicate, 5-10 parts of nano-montmorillonite, 1-5 parts of toughening agent, 1-3 parts of nucleating agent and 1-2 parts of antioxidant.

2. The low temperature resistant plastic alloy material according to claim 1, characterized in that: The melt mass flow rate of polycarbonate at 300° C. and 1.2 kg is 10-40 g / 10 min.

3. The low temperature resistant plastic alloy material according to claim 1, characterized in that: The particle size of polyvinyl chloride is 100-500μm.

4. The low temperature resistant plastic alloy material according to claim 1, characterized in that: The silane coupling agent is an aminosilane coupling agent, preferably aminopropyltriethoxysilane.

5. The low temperature resistant plastic alloy material according to claim 1, characterized in that: The toughening agent is at least one of methyl methacrylate-butadiene-styrene copolymer, methyl methacrylate-acrylic acid copolymer and ethylene-butyl acrylate copolymer.

6. The low temperature resistant plastic alloy material according to claim 1, characterized in that: The nucleating agent is at least one of talc, calcium carbonate and sodium carbonate.

7. The low temperature resistant plastic alloy material according to claim 1, characterized in that: The antioxidant is 2,4-di-tert-butylphenol.

8. A method for preparing the low temperature resistant plastic alloy material according to any one of claims 1 to 7, characterized in that: The steps include: S1, adding tetraethyl orthosilicate and silane coupling agent to ethanol aqueous solution and ultrasonically treating for 10-30 minutes, adjusting the pH value of the system to 9-10 with ammonia water, adding polyvinyl chloride, refluxing at 80-90° C. and stirring for 1-2 hours, adding carboxyl-terminated polyamide amine and stirring for 10-30 minutes, cooling to room temperature, filtering, washing, and vacuum drying to obtain pretreated polyvinyl chloride; S2, adding nano-montmorillonite to isopropanol for ultrasonic treatment for 1-2 hours, adding saturated ammonia water thereto under stirring, reflux at 70-80° C. for 1-2 hours, filtering, washing, vacuum drying, mixing with pretreated polyvinyl chloride, stirring at 120-150° C. for 5-15 minutes, cooling to room temperature, adding polycarbonate, toughening agent, nucleating agent, antioxidant and stirring for 10-30 minutes to obtain a premix; S3, extruding the premix at a temperature of 200-220°C, and cooling.

9. The method for preparing the low temperature resistant plastic alloy material according to claim 8, characterized in that: The ultrasound frequency in S1 is 5-15 Hz, and the ultrasound frequency in S2 is 5-15 kHz.

10. The method for preparing the low temperature resistant plastic alloy material according to claim 8, characterized in that: In S3, a twin-screw extruder is used for extrusion, and the screw speed is 100-150r / min.

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