High and low temperature resistant insulating nylon alloy and preparation method thereof

Abstract

The invention relates to the technical field of nylon alloy preparation, and particularly discloses a high and low temperature resistant insulating nylon alloy and a preparation method thereof.The preparation method comprises the following steps that S1, raw materials including nylon 6, polyphenylene sulfide, boron nitride, silicon carbide nanowires, a bismaleimide compatilizer, an antioxidant and calcium stearate are prepared; s2, pretreatment: carrying out vacuum drying on nylon 6 and polyphenylene sulfide through a vacuum drying oven, carrying out forced air drying on boron nitride, carrying out silane coupling treatment, and carrying out ultrasonic dispersion on the silicon carbide nanowire in absolute ethyl alcohol through an ultrasonic cleaning machine; and S3, stirring and mixing the pretreated materials in a mixing machine. According to the preparation method of the high and low temperature resistant insulating nylon alloy, a silicon carbide nanowire and boron nitride compound filler are introduced, a three-dimensional insulating network is formed, the high-temperature volume resistivity is increased to be larger than 1016 omega.cm, meanwhile, the high-temperature stability of the silicon carbide nanowire effectively makes up the low-temperature defect of BN, and the material can still keep the impact strength larger than or equal to 10 kJ / m < 2 > at the low temperature.

Description

Technical Field

[0001] The present invention relates to the technical field of nylon alloy preparation, and in particular to a high and low temperature resistant insulating nylon alloy and a preparation method thereof. Background Art

[0002] Nylon alloy materials are composite materials based on nylon (polyamide) and formed by blending with other polymer materials (such as polyphenylene sulfide PPS) or functional fillers, combining the toughness and corrosion resistance of nylon with the high rigidity and heat resistance of the reinforcing phase.

[0003] Traditional nylon alloys use a single boron nitride (BN) filler, and the volume resistivity at high temperatures is only 10 15 Ω·cm, which cannot meet the requirement of >10 16 Ω·cm in scenarios such as high-voltage connectors for new energy vehicles. Moreover, due to the polarity difference between PA6 and PPS, phase separation occurs, and the traditional maleic anhydride grafted compatibilizer (MAH-g-PP) only improves the interfacial strength by 30%, and is prone to cracking during thermal cycling. In addition, in the traditional process, when using a single mechanical stirring to mix materials, the nano-fillers (SiC NWs) form agglomerates due to insufficient shear force during high-speed mixing, reducing the material homogeneity and mechanical properties.

[0004] Therefore, it is necessary to propose a high and low temperature resistant insulating nylon alloy and a preparation method thereof to solve the above problems. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to overcome the defects existing in the prior art and solve the problems existing in the prior art in the background art.

[0006] To achieve the above object, the technical solution adopted by the present invention is as follows:

[0007] A preparation method of a high and low temperature resistant insulating nylon alloy, comprising the following steps:

[0008] S1: Raw material preparation, including nylon 6, polyphenylene sulfide, boron nitride, silicon carbide nanowires, bismaleimide compatibilizer, antioxidant, calcium stearate;

[0009] S2: Pretreatment, vacuum drying nylon 6 and polyphenylene sulfide through a vacuum drying oven, drying boron nitride through air drying and performing silane coupling treatment, and ultrasonically dispersing silicon carbide nanowires in absolute ethanol through an ultrasonic cleaner;

[0010] S3: Stir and mix the pretreated materials in a mixer, and the specific steps are as follows:

[0011] Stage 1, initially mix nylon 6 and polyphenylene sulfide matrix resin at 25°C;

[0012] In Stage 2, a boron nitride and silicon carbide nanowire ethanol dispersion is added at 60°C, and ultrasonic waves are turned on to achieve the directional dispersion of the nano-fillers.

[0013] In Stage 3, a bismaleimide compatibilizer, an antioxidant, and calcium stearate are added at 80°C.

[0014] S4: The above-mentioned mixed materials enter a twin-screw extruder through a screw conveyor to extrude a molten nylon alloy strip.

[0015] S5: The extruded molten nylon alloy strip is cooled by water, drawn into strips, and pelletized.

[0016] S6: After drying, the moisture content of the pellets is <0.03%, and they are sealed and packaged for standby.

[0017] Preferably, the mass percentages of the raw materials are as follows: 60% nylon 6, 25% polyphenylene sulfide, 5% boron nitride, 3% silicon carbide nanowires, 4% bismaleimide compatibilizer, 1% antioxidant, and 2% calcium stearate.

[0018] Preferably, in step S4, the aspect ratio of the twin-screw extruder is at least 40:1, and the temperature gradient is 230°C → 275°C.

[0019] Preferably, in step S4, the dispersion degree of the fillers in the stirred and mixed materials needs to be verified by SEM, and after passing the verification, they enter the extrusion process through a screw conveyor.

[0020] Preferably, the mixer includes a tank body, a jacket arranged on the periphery of the tank body, and a feed inlet arranged at the upper end of the tank body.

[0021] An ultrasonic probe is penetrated through the side of the tank body, one end of the ultrasonic probe extends into the interior of the tank body to contact the materials, and the other end is connected to an ultrasonic generator.

[0022] A heating device is arranged in the jacket, a stirring mechanism is arranged in the tank body, the stirring mechanism includes an inner shaft rotatably arranged in the middle of the tank body, a third stirring blade is arranged on the side of the inner shaft, and a second stirring blade is arranged at the end of the third stirring blade far away from the inner shaft.

[0023] A feeding mechanism is arranged on the outer periphery of the inner cavity of the tank body. The feeding mechanism includes an inner cylinder rotatably arranged on the outer periphery of the inner cavity of the tank body, and the rotation direction of the inner cylinder is opposite to that of the inner shaft. The upper end of the inner cylinder corresponds to the ultrasonic probe, a dragon blade is arranged on the outer side of the inner cylinder, and the second stirring blade and the third stirring blade are located in the inner cavity of the inner cylinder.

[0024] Preferably, the upper end of the tank body is provided with a coaxial reversing assembly for driving the inner shaft and the inner cylinder to rotate, the coaxial reversing assembly includes an outer shaft rotatably arranged at the upper end of the tank body, the upper end of the outer shaft protrudes from the top of the tank body, and the lower end of the outer shaft extends to the inner cavity of the tank body, the inner shaft is rotatably arranged on the inner side of the outer shaft, and the upper end of the inner shaft protrudes from the upper end of the outer shaft, the upper end of the inner cylinder is fixed to the lower end side wall of the outer shaft, the upper end of the outer shaft and the upper end of the inner shaft are both provided with a second bevel gear, one end of the top of the tank body is provided with a second driving source, and the output end of the second driving source is provided with a first bevel gear driven to rotate by the second driving source and meshing with the two second bevel gears.

[0025] Preferably, a uniform material distribution mechanism is provided at the upper end of the inner cavity of the tank body, and the uniform material distribution mechanism includes a ring-shaped storage hopper fixedly arranged on the outer side of the lower end of the outer shaft, the top of the storage hopper corresponds to the feed port, and a second end face gear ring corresponding to the storage hopper is fixedly arranged on the outer side of the upper end of the inner shaft, and a separation cylinder is transversely arranged on the side wall of the storage hopper, and a dragon shaft is rotatably arranged on the inner side of the separation cylinder, and through holes are evenly arranged on the bottom of the separation cylinder, and one end of the dragon shaft extends to the top of the second end face gear ring and meshes with the second end face gear ring.

[0026] Preferably, a height adjustment mechanism for adjusting the height of the third stirring blade is provided on the inner shaft, and the height adjustment mechanism includes an auxiliary shell evenly arranged along the height direction of the inner shaft, a lifting sleeve is movably sealed on the outer side of the auxiliary shell, the third stirring blade is fixed to the side wall of the lifting sleeve, adjacent lifting sleeves are connected as a whole by a connecting frame, a traction frame is provided on the top of the uppermost lifting sleeve, a first end face gear ring is provided at the bottom of the storage hopper, a rotating shaft corresponding to the first end face gear ring is rotatably provided on the side wall of the upper end of the inner shaft, a first gear meshing with the first end face gear ring is provided on the end of the rotating shaft away from the inner shaft, a cam is provided on the other end of the rotating shaft, an elliptical first guide groove is provided on the outer side wall of the cam, and a first guide shaft movably connected to the first guide groove is provided on the upper end of the traction frame.

[0027] Preferably, a first arc-shaped stirring blade is provided on the lower end side wall of the inner shaft, and the first stirring blade corresponds to the bottom of the inner cylinder.

[0028] The present application also includes an embodiment, specifically a high and low temperature resistant insulating nylon alloy, which is prepared by a high and low temperature resistant insulating nylon alloy preparation method.

[0029] Compared with the prior art, the beneficial effects of the present invention include:

[0030] 1. The preparation method of the high and low temperature resistant insulating nylon alloy forms a three-dimensional insulating network by introducing silicon carbide nanowires and boron nitride composite fillers, and the high temperature volume resistivity is increased to >10 16Ω·cm, and the high temperature stability of silicon carbide nanowires effectively compensates for the low temperature defects of BN, allowing the material to maintain ≥10kJ / m at low temperatures 2 In addition, the new bismaleimide compatibilizer improves the interfacial shear strength of nylon 6 and polyphenylene sulfide through covalent bridging of amide bonds and sulfide bonds, which is significantly better than traditional MAH-g-PP compatibilizers and solves the problem of easy cracking of nylon alloys due to interface weakening.

[0031] 2. The improved mixer integrates ultrasound and gradient temperature control to improve the uniformity of nanofiller dispersion while avoiding thermal oxidation degradation of polyphenylene sulfide caused by high-temperature mixing. At the same time, the stirring mechanism in the mixer cooperates with the feeding mechanism to improve the mixing effect and efficiency. The inner cylinder drives the Jiaolong blade to rotate and rotates in the opposite direction to the inner shaft. The bottom material can be transported upward to the inside of the inner cylinder to be stirred by the stirring mechanism, avoiding the deposition of the bottom material. At the same time, since the inner cylinder is located outside the inner cavity of the tank body, the material can be transported upward along the inner wall of the tank body, which is convenient for the material to be heated evenly and improves the heating effect. At the same time, the continuous upward transportation of the material can continuously bring the material close to the ultrasonic probe, which is convenient for the ultrasonic probe to disperse the nanofiller. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The disclosure of the present invention is described with reference to the accompanying drawings. It should be understood that the drawings are for illustrative purposes only and are not intended to limit the scope of protection of the present invention. In the accompanying drawings, the same reference numerals are used to refer to the same components. Among them:

[0033] Figure 1 A schematic structural diagram schematically shows a flow chart of a method for preparing a high and low temperature resistant insulating nylon alloy according to one embodiment of the present invention;

[0034] Figure 2 A schematic diagram of the structure of a mixer according to one embodiment of the present invention is shown;

[0035] Figure 3 Schematically shows a cross-sectional structural diagram of a mixer proposed according to one embodiment of the present invention;

[0036] Figure 4 The schematic diagram shows the structure of the mixer according to one embodiment of the present invention with the inner cylinder and the inner shaft in a disassembled state;

[0037] Figure 5 The schematic diagram shows the structure of the protective shell, the storage hopper, the first bevel gear, and the second bevel gear in the mixer according to one embodiment of the present invention in a disassembled state;

[0038] Figure 6Schematically shows the structural schematic diagram of the storage hopper in the mixer according to an embodiment of the present invention;

[0039] Figure 7 Schematically shows Figure 6 The structural schematic diagram from another perspective on the basis;

[0040] Figure 8 Schematically shows the structural schematic diagram of the lifting rod, inner shaft, outer shaft, storage hopper, and auger shaft in the mixer in a disassembled state according to an embodiment of the present invention;

[0041] Figure 9 Schematically shows the structural schematic diagram of the traction frame and the cam in the mixer in a disassembled state according to an embodiment of the present invention;

[0042] Figure 10 Schematically shows the sectional structural schematic diagram of the connection between the auxiliary shell and the third stirring blade in the mixer according to an embodiment of the present invention;

[0043] Figure 11 Schematically shows the sectional structural schematic diagram of the connection between the third stirring blade and the second stirring blade in the mixer according to an embodiment of the present invention.

[0044] Reference numerals in the figure: 1, tank body; 2, jacket; 3, ultrasonic probe; 4, feed inlet; 5, bracket; 6, first driving source; 7, inner cylinder; 8, auger blade; 9, storage hopper; 10, first stirring blade; 11, inner shaft; 12, protective shell; 13, separation cylinder; 14, second stirring blade; 15, third stirring blade; 16, lifting sleeve; 17, second driving source; 18, first bevel gear; 19, second bevel gear; 20, lifting rod; 21, outer shaft; 22, traction frame; 23, through hole; 24, first end face gear ring; 25, first gear; 26, rotating shaft; 27, second end face gear ring; 28, cam; 29, first guide groove; 30, second gear; 31, auger shaft; 32, first guide shaft; 33, auxiliary shell; 34, connecting frame; 35, traction plate; 36, second guide groove; 37, third guide groove; 38, second guide shaft; 39, connecting shaft; 40, driving rod; 41, third guide shaft; 42, fourth guide groove; 43, guide block. Detailed implementation manners

[0045] It is easy to understand that according to the technical solution of the present invention, without changing the essence of the present invention, those of ordinary skill in the art can propose various interchangeable structural forms and implementation manners. Therefore, the following detailed implementation manners and the accompanying drawings are only exemplary descriptions of the technical solution of the present invention, and should not be regarded as the whole of the present invention or as a limitation or restriction on the technical solution of the present invention.

[0046] According to an embodiment of the present invention, combined with Figure 1 shown, a preparation method of a high and low temperature resistant insulating nylon alloy includes the following steps:

[0047] Step 1: Raw material preparation, including 60% nylon 6 (PA6), 25% polyphenylene sulfide (PPS), 5% boron nitride (BN), 3% silicon carbide nanowires (SiC NWs), 4% bismaleimide (BMI) compatibilizer, 1% antioxidant, and 2% calcium stearate (lubricant), and the percentages are mass percentages;

[0048] Step 2: Pretreatment. Vacuum dry nylon 6 in a vacuum drying oven at 80°C for 6 hours, and vacuum dry polyphenylene sulfide at 120°C for 6 hours. Its function is to remove moisture and prevent hydrolysis degradation during melt blending. Dry boron nitride in a blast dryer at 120°C for 4 hours and perform silane coupling treatment (KH550). Its function is to enhance the interfacial bonding force with the resin through the silane coupling agent (KH550). Ultrasonically disperse silicon carbide nanowires in absolute ethanol for 30 minutes using an ultrasonic cleaner. Its function is to break the nanowire agglomeration by ethanol ultrasonic treatment to form a stable suspension;

[0049] Step 3: Stir and mix the pretreated materials in a mixer. The specific steps are as follows:

[0050] Stage 1: Initially mix nylon 6 and polyphenylene sulfide matrix resin at 25°C for 5 - 10 minutes with a rotation speed of 20 rpm;

[0051] Stage 2: Add boron nitride and silicon carbide nanowire ethanol dispersion at 60°C, turn on the ultrasonic wave to achieve directional dispersion of the nano - fillers for 15 - 20 minutes with a rotation speed of 50 rpm;

[0052] Stage 3: Add bismaleimide compatibilizer, antioxidant, and calcium stearate at 80°C for 5 - 10 minutes with a rotation speed of 30 rpm, and mix at low temperature to prevent PPS degradation;

[0053] Step 4: Verify the filler dispersion degree by SEM. After passing the verification, enter the extrusion process through a screw conveyor. In the extrusion process, extrude the material into a molten nylon alloy strip through a twin - screw extruder. The long - diameter ratio of the twin - screw extruder is at least 40:1, the temperature gradient is 230°C → 275°C, the screw rotation speed is 200 rpm (low shear to prevent filler damage), and vacuum exhaust (-0.08 MPa) to remove ethanol residues;

[0054] Step 5: The water temperature is 35°C (to prevent internal stress caused by sudden cooling). After the particles are dried, the moisture content is <0.03%, and then they are sealed and packaged for standby.

[0055] The above - mentioned mixer is an improved type. According to an embodiment of the present invention, combined with Figures 2 - 5As shown, the mixer includes a tank body 1, a jacket 2 arranged on the periphery of the tank body 1, and a feed inlet 4 arranged at the upper end of the tank body 1. An ultrasonic probe 3 is arranged through the side of the tank body 1. There are at least three ultrasonic probes 3, which are evenly arranged around the upper end of the tank body 1. One end of the ultrasonic probe 3 extends into the interior of the tank body 1 to contact the material, and the other end is connected to an ultrasonic generator. The model of the ultrasonic generator is preferably THD-T6 type or MFD350 series. A heating device is arranged in the jacket 2. The heating device adopts the existing technology and will not be elaborated too much. A stirring mechanism is arranged in the tank body 1. The stirring mechanism includes an inner shaft 11 rotatably arranged in the middle of the tank body 1. A plurality of third stirring blades 15 are arranged on the side of the inner shaft 11. A second stirring blade 14 is arranged at one end of the third stirring blade 15 away from the inner shaft 11. The second stirring blade 14 is in a vertical state during the stirring state. A feeding mechanism is arranged on the periphery of the inner cavity of the tank body 1. The feeding mechanism includes an inner cylinder 7 rotatably arranged on the periphery of the inner cavity of the tank body 1, and the rotation direction of the inner cylinder 7 is opposite to that of the inner shaft 11. The upper end of the inner cylinder 7 corresponds to the ultrasonic probe 3. A dragon blade 8 is arranged on the outer side of the inner cylinder 7. The second stirring blade 14 and the third stirring blade 15 are located in the inner cavity of the inner cylinder 7. An arc-shaped first stirring blade 10 is arranged on the side wall of the lower end of the inner shaft 11, and the first stirring blade 10 corresponds to the bottom of the inner cylinder 7, and can stir the material to the periphery.

[0056] The reverse rotation of the above-mentioned inner shaft 11 and inner cylinder 7 is realized by a coaxial reverse rotation assembly arranged at the upper end of the tank body 1. According to an embodiment of the present invention, in combination with Figures 4 - 5 As shown, as a preferred embodiment, the coaxial reverse rotation assembly includes an outer shaft 21 rotatably arranged at the upper end of the tank body 1. The upper end of the outer shaft 21 protrudes from the top of the tank body 1. The lower end of the outer shaft 21 extends into the inner cavity of the tank body 1. The inner shaft 11 is rotatably arranged inside the outer shaft 21. The inner shaft 11 and the outer shaft 21 are coaxial, and the upper end of the inner shaft 11 protrudes from the upper end of the outer shaft 21. The upper end of the inner cylinder 7 is fixed to the side wall of the lower end of the outer shaft 21 through an "L"-shaped connecting rod. Second bevel gears 19 are arranged at the upper ends of both the outer shaft 21 and the inner shaft 11. A second driving source 17 is arranged at one end of the top of the tank body 1. The second driving source 17 is preferably a reduction motor. The output end of the second driving source 17 is provided with a first bevel gear 18 that is driven to rotate by the second driving source 17 and meshes with the two second bevel gears 19.

[0057] According to an embodiment of the present invention, in combination with Figures 3 - 9It is shown that in order to achieve uniform dispersion of materials, a uniform material distribution mechanism is arranged at the upper end of the inner cavity of the tank body 1, and the uniform material distribution mechanism includes a ring-shaped storage hopper 9 fixedly arranged on the outer side of the lower end of the outer shaft 21, the top of the storage hopper 9 is open, and the top of the storage hopper 9 corresponds to the feed port 4, and a second end face gear ring 27 corresponding to the storage hopper 9 is fixedly arranged on the outer side of the upper end of the inner shaft 11, and a separation cylinder 13 is transversely arranged on the side wall of the storage hopper 9, and there are multiple separation cylinders 13, which are evenly arranged around, and a dragon shaft 31 is rotatably arranged on the inner side of the separation cylinder 13, and through holes 23 are evenly arranged on the bottom of the separation cylinder 13, and one end of the dragon shaft 31 extends to the top of the second end face gear ring 27 and meshes with the second end face gear ring 27.

[0058] According to one embodiment of the present invention, Figures 4 - 9 As shown, in order to further improve the stirring effect, a height adjustment mechanism for adjusting the height of the third stirring blade 15 is provided on the inner shaft 11, and the height adjustment mechanism includes an auxiliary shell 33 evenly arranged along the height direction of the inner shaft 11, and a lifting sleeve 16 is provided on the outer side of the auxiliary shell 33. The third stirring blade 15 is fixed to the side wall of the lifting sleeve 16, and the adjacent lifting sleeves 16 are connected as a whole through a connecting frame 34. The top of the uppermost lifting sleeve 16 is provided with a traction frame 22, and the bottom of the storage hopper 9 is provided with a A first end face gear ring 24 is provided, and a rotating shaft 26 corresponding to the first end face gear ring 24 is rotatably provided on the side wall of the upper end of the inner shaft 11. A first gear 25 meshing with the first end face gear ring 24 is provided at one end of the rotating shaft 26 away from the inner shaft 11, and a cam 28 is provided at the other end of the rotating shaft 26. An elliptical first guide groove 29 is provided on the outer side wall of the cam 28. A first guide shaft 32 movably guided and connected to the first guide groove 29 is provided on the upper end of the traction frame 22, so that the rotation of the cam 28 can drive the multiple lifting sleeves 16 to rise and fall.

[0059] According to one embodiment of the present invention, Figures 10 - 11It is shown that in order to facilitate the cleaning of the inner wall of the inner cylinder 7 during material discharging, an inclination angle adjusting component for adjusting the inclination angle of the second stirring blade 14 is provided on the third stirring blade 15. The inclination angle adjusting component includes a connecting shaft 39 movably arranged inside the third stirring blade 15, and the second stirring blade 14 is fixed to one end of the connecting shaft 39 away from the lifting sleeve 16. The auxiliary shell 33 is of a hollow structure. A lifting rod 20 is vertically movably arranged inside the inner shaft 11, and at the same time, the lifting rod 20 also penetrates through the auxiliary shell 33. The upper end of the lifting rod 20 protrudes from the top of the inner shaft 11. A traction plate 35 is movably arranged along the radial direction of the inner shaft 11 at the corresponding position of the inner side of the auxiliary shell 33 and the third stirring blade 15. An inclined second guide groove 36 is arranged on one side of the traction plate 35 close to the lifting rod 20. A second guide shaft 38 that is movably and guidingly matched with the second guide groove 36 is arranged at the corresponding position of the side wall of the lifting rod 20 and the second guide groove 36. A vertical third guide groove 37 is arranged on one side of the traction plate 35 close to the third stirring blade 15. One end of the third stirring blade 15 close to the lifting sleeve 16 is movably arranged along the radial direction of the inner shaft 11 with a driving rod 40. One end of the driving rod 40 extends to the inside of the auxiliary shell 33 and is provided with a third guide shaft 41 that is movably and guidingly matched with the third guide groove 37. The other end of the driving rod 40 is movably sleeved outside the connecting shaft 39. A guide block 43 is arranged on the inner wall of one end of the driving rod 40 close to the connecting shaft 39. A spiral fourth guide groove 42 is arranged on the outer wall of one end of the connecting shaft 39 close to the driving rod 40. The guide block 43 is movably and guidingly connected to the inside of the fourth guide groove 42. Thus, when the driving rod 40 moves along the radial direction of the inner shaft 11, the connecting shaft 39 can drive the second stirring blade 14 to rotate, and when the second stirring blade 14 is in a fully inclined state, the side of the second stirring blade 14 away from the third stirring blade 15 can be attached to the inner wall of the inner cylinder 7. A support 5 is arranged at the upper end of the tank body 1, and a first driving source 6 for driving the lifting rod 20 to lift is arranged at the upper end of the support 5. The first driving source 6 is preferably a cylinder, and the output end of the first driving source 6 is rotatably connected to the upper end of the lifting rod 20 to avoid affecting the rotation of the inner shaft 11. In addition, in order to facilitate the reset of the second stirring blade 14 and the connecting shaft 39, a flange 45 is arranged on the outer wall of one end of the connecting shaft 39 close to the second stirring blade 14, and a spring 44 is arranged on one side of the flange 45 close to the second stirring blade 14. When the connecting shaft 39 is pushed by the driving rod 40, the spring 44 can be compressed. In order to prevent the driving rod 40 from interfering with the up and down displacement of the lifting sleeve 16, a through groove is arranged at the corresponding position of the side surface of the auxiliary shell 33 and the driving rod 40. One end of the first stirring blade 10 extends to the inside of the auxiliary shell 33 through this through groove. Thus, when the lifting sleeve 16 drives the third stirring blade 15 to move up and down, one end of the driving rod 40 can displace in this through groove.

[0060] It should be noted that a protective shell 12 for protecting structures such as the first end face gear ring 24 and the second end face gear ring 27 is arranged on the outer side of the lower end of the storage hopper 9, and both the inner shaft 11 and the traction frame 22 penetrate through the protective shell 12 and are movably connected to the protective shell 12.

[0061] In addition, this application also includes an embodiment, specifically a high and low temperature resistant insulating nylon alloy, which is prepared by using the above-mentioned preparation method of high and low temperature resistant insulating nylon alloy.

[0062] Regarding the specific working principle of the improved mixer, when in use, various raw materials are added into the interior of the tank body 1 through the feed port 4, and the materials will fall to the inner side of the storage hopper 9. Control the second drive source 17 to drive the first bevel gear 18 to rotate. The first bevel gear 18 drives the inner shaft 11 and the outer shaft 21 to rotate through two second bevel gears 19, and the rotation directions of the inner shaft 11 and the outer shaft 21 are opposite. The outer shaft 21 drives the inner cylinder 7 to rotate, and the inner cylinder 7 drives the auger blade 8 to operate. The inner shaft 11 drives the third stirring blade 15, the second stirring blade 14, and the first stirring blade 10 to rotate. When the outer shaft 21 rotates, it will also drive the storage hopper 9 to rotate accordingly. When the inner shaft 11 rotates, it will also drive the second end face gear ring 27 to rotate accordingly. As a result, the second gear 30 located on the storage hopper 9 is driven to rotate by the second end face gear ring 27, and the first gear 25 located on the inner shaft 11 is driven to rotate by the first end face gear ring 24. When the second gear 30 rotates, it drives the auger shaft 31 to rotate, thereby conveying the materials in the storage hopper 9 to the separation cylinder 13. The materials passing through the separation cylinder 13 can fall through the through hole 23. And because the storage hopper 9 drives the separation cylinder 13 to rotate, the materials can be evenly dispersed in the inner cylinder 7. When the first gear 25 rotates, it will drive the cam 28 to rotate through the rotating shaft 26. Under the action of the first guide groove 29 and the first guide shaft 32, the reciprocating lifting of the traction frame 22 can be realized. The traction frame 22 drives the lifting sleeve 16 to lift and lower, and the lifting sleeve 16 drives the second stirring blade 14 and the third stirring blade 15 to continuously lift and lower, continuously changing the height while rotating, improving the stirring and mixing effect and efficiency. In addition, when the arc-shaped first stirring blade 10 stirs, it can stir the materials towards the periphery, so that the auger blade 8 can convey the bottom materials upward along the inner wall of the tank body 1, facilitating the heating of the materials by the heating device in the jacket 2 and also avoiding sedimentation. The conveyed materials will approach the ultrasonic probe 3, and the ultrasonic probe 3 can realize the directional dispersion of the nano-filler in stage 2;

[0063] In addition, when discharging after the stirring and mixing is completed, the second driving source 17 is controlled to reverse, and the first driving source 6 is controlled to drive the lifting rod 20 to move downward. The lifting rod 20 drives the second guide shaft 38 to move downward. The second guide shaft 38 drives the traction plate 35 to move through the cooperation of the second guide groove 36. The traction plate 35 drives the driving rod 40 to move through the third guide shaft 41. The driving rod 40 drives the connecting shaft 39 to rotate through the cooperation of the guide block 43 and the fourth guide groove 42. The connecting shaft 39 drives the second stirring blade 14 to rotate to an inclined position. At the same time, due to the thrust of the driving rod 40, the connecting shaft 39 will also compress the spring 44 through the flange 45. Then, one side of the second stirring blade 14 fits against the inner wall of the inner cylinder 7. After the material is discharged, the second driving source 17 continues to operate for a period of time. During this period, due to the reverse rotation of the inner shaft 11 and the outer shaft 21, the auger blade 8 can convey and push down the material adhering to the inner wall of the tank body 1. The inclined rotation and vertical displacement of the second stirring blade 14 can push down the material on the inner wall of the inner cylinder 7, avoiding material waste and also facilitating subsequent cleaning operations.

[0064] The technical scope of the present invention is not limited to the content described above. Those skilled in the art can make various deformations and modifications to the above embodiments without departing from the technical idea of the present invention, and these deformations and modifications should all fall within the protection scope of the present invention.

Claims

1. A preparation method of a high and low temperature resistant insulating nylon alloy, characterized in that, It includes the following steps: S1: Raw material preparation, including nylon 6, polyphenylene sulfide, boron nitride, silicon carbide nanowires, bismaleimide compatibilizer, antioxidant, calcium stearate; S2: Pretreatment. Nylon 6 and polyphenylene sulfide are vacuum-dried through a vacuum drying oven. Boron nitride is dried through air-blowing and treated with silane coupling. Silicon carbide nanowires are ultrasonically dispersed in absolute ethanol through an ultrasonic cleaner; S3: Stir and mix the pretreated materials in a mixer. The specific steps are as follows: Stage 1, initially mix nylon 6 and polyphenylene sulfide matrix resin at 25°C; Stage 2, add boron nitride and ethanol dispersion of silicon carbide nanowires at 60°C, turn on the ultrasonic wave to achieve directional dispersion of nano-fillers; Stage 3, add bismaleimide compatibilizer, antioxidant, calcium stearate at 80°C; S4: The above mixed materials enter a twin-screw extruder through a screw conveyor to extrude molten nylon alloy strips; S5: Water-cool and draw and cut the extruded molten nylon alloy strips into pellets; S6: After drying the pellets, the moisture content is <0.03%, and they are sealed and packaged for standby.

2. The preparation method of a high and low temperature resistant insulating nylon alloy according to claim 1, wherein: The mass percentages of the raw materials are respectively: 60% of nylon 6, 25% of polyphenylene sulfide, 5% of boron nitride, 3% of silicon carbide nanowires, 4% of bismaleimide compatibilizer, 1% of antioxidant, 2% of calcium stearate.

3. A preparation method of a high and low temperature resistant insulating nylon alloy according to claim 1, characterized in that: In step S4, the length-diameter ratio of the twin-screw extruder is at least 40:1, and the temperature gradient is 230°C → 275°C.

4. A method for preparing a high and low temperature resistant insulating nylon alloy according to claim 1, characterized in that: In step S4, the stirred and mixed materials need to be verified for the filler dispersion degree through SEM, and after passing, they enter the extrusion process through a screw conveyor.

5. A method for preparing a high and low temperature resistant insulating nylon alloy according to claim 1, characterized in that: The mixer includes a tank body, a jacket arranged on the periphery of the tank body, and a feed inlet arranged at the upper end of the tank body; An ultrasonic probe is penetrated and arranged on the side of the tank body. One end of the ultrasonic probe extends into the interior of the tank body to contact the materials, and the other end is connected to an ultrasonic generator; A heating device is arranged in the jacket, a stirring mechanism is arranged in the tank body. The stirring mechanism includes an inner shaft rotatably arranged in the middle of the tank body. A third stirring blade is arranged on the side of the inner shaft, and a second stirring blade is arranged at the end of the third stirring blade away from the inner shaft; A feeding mechanism is arranged on the periphery of the inner cavity of the tank body. The feeding mechanism includes an inner cylinder rotatably arranged on the periphery of the inner cavity of the tank body, and the rotation direction of the inner cylinder is opposite to that of the inner shaft. The upper end of the inner cylinder corresponds to the ultrasonic probe. A dragon blade is arranged on the outside of the inner cylinder, and the second stirring blade and the third stirring blade are located in the inner cavity of the inner cylinder.

6. A method for preparing a high and low temperature resistant insulating nylon alloy according to claim 5, characterized in that: A coaxial reverse rotation assembly for driving the rotation of the inner shaft and the inner cylinder is arranged at the upper end of the tank body. The coaxial reverse rotation assembly includes an outer shaft rotatably arranged at the upper end of the tank body. The upper end of the outer shaft protrudes from the top of the tank body, and the lower end of the outer shaft extends into the inner cavity of the tank body. The inner shaft is rotatably arranged inside the outer shaft, and the upper end of the inner shaft protrudes from the upper end of the outer shaft. The upper end of the inner cylinder is fixed to the side wall of the lower end of the outer shaft. Second bevel gears are arranged at the upper ends of the outer shaft and the inner shaft respectively. A second driving source is arranged at one end of the top of the tank body, and an output end of the second driving source is provided with a first bevel gear that is driven to rotate by the second driving source and meshes with the two second bevel gears.

7. A method for preparing a high and low temperature resistant insulating nylon alloy according to claim 6, characterized in that: A uniform material distribution mechanism is provided at the upper end of the inner cavity of the tank body, and the uniform material distribution mechanism includes a ring-shaped storage hopper fixedly arranged on the outside of the lower end of the outer shaft, the top of the storage hopper corresponds to the feed port, and a second end face gear ring corresponding to the storage hopper is fixedly provided on the outside of the upper end of the inner shaft, a separation cylinder is transversely provided on the side wall of the storage hopper, a dragon shaft is rotatably provided on the inner side of the separation cylinder, and through holes are uniformly provided on the bottom of the separation cylinder, and one end of the dragon shaft extends to the top of the second end face gear ring and meshes with the second end face gear ring.

8. A method for preparing a high and low temperature resistant insulating nylon alloy according to claim 7, characterized in that: The inner shaft is provided with a height adjustment mechanism for adjusting the height of the third stirring blade, and the height adjustment mechanism includes an auxiliary shell evenly arranged along the height direction of the inner shaft, a lifting sleeve is movably sealed on the outer side of the auxiliary shell, the third stirring blade is fixed to the side wall of the lifting sleeve, adjacent lifting sleeves are connected as a whole by a connecting frame, a traction frame is provided on the top of the uppermost lifting sleeve, a first end face gear ring is provided at the bottom of the storage hopper, a rotating shaft corresponding to the first end face gear ring is rotatably provided on the side wall of the upper end of the inner shaft, a first gear meshing with the first end face gear ring is provided on the end of the rotating shaft away from the inner shaft, a cam is provided at the other end of the rotating shaft, an elliptical first guide groove is provided on the outer side wall of the cam, and a first guide shaft movably connected to the first guide groove is provided on the upper end of the traction frame.

9. A method for preparing a high and low temperature resistant insulating nylon alloy according to claim 5, characterized in that: The lower end side wall of the inner shaft is provided with an arc-shaped first stirring blade, and the first stirring blade corresponds to the bottom of the inner cylinder.

10. A high and low temperature resistant insulating nylon alloy, characterized in that: The high and low temperature resistant insulating nylon alloy is prepared by the preparation method according to any one of claims 1 to 9.

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