In-situ fiber reinforced polymer material, preparation method thereof and preparation method of release film

Abstract

The application provides an in-situ fiber reinforced polymer material and a preparation method thereof, and a preparation method of an isolation film, and belongs to the field of plastic films.The application provides an in-situ fiber reinforced polymer material and a preparation method thereof, which comprises the following steps: in-situ fiberizing a reinforcing polymer in a molten fluoropolymer, so as to obtain the in-situ fiber reinforced polymer material.The microfibers generated by in-situ fiberizing the reinforcing polymer in the application improve the mechanical properties of the in-situ fiber reinforced polymer material, and the compatibility of the microfibers obtained by in-situ fiberizing with the fluoropolymer material is good and the microfibers are uniformly dispersed, which further improves the mechanical properties of the in-situ fiber reinforced polymer material, so that the isolation film prepared from the in-situ fiber reinforced polymer material has excellent mechanical properties.

Description

Technical Field

[0001] This invention relates to the field of plastic films, and more particularly to an in-situ fiber-reinforced polymer material and its preparation method, as well as a method for preparing a separator membrane. Background Technology

[0002] In the process of composite material molding, the release film plays the role of isolating the prepreg resin, especially the fluorinated release film, because this type of film has a lower surface energy and its peelability after use is better than that of films made of other materials.

[0003] In existing technologies, fluoropolymers are typically used to directly prepare release films, but these films still have relatively poor mechanical properties. For example, they are prone to breakage when peeled off from the resin surface. Summary of the Invention

[0004] The purpose of this invention is to provide an in-situ fiber-reinforced polymer material and its preparation method, as well as a method for preparing a separator membrane. The separator membrane prepared by the in-situ fiber-reinforced polymer material of this invention has excellent mechanical properties.

[0005] This invention provides a method for preparing in-situ fiber-reinforced polymer materials, comprising the following steps:

[0006] The in-situ fiber-reinforced polymer material is obtained by in-situ fiberizing the reinforcing polymer in a highly elastic state in a molten fluoropolymer.

[0007] Preferably, the fluoropolymer material includes one or more of ethylene-tetrafluoroethylene copolymer, perfluoroethylene-propylene copolymer, vinylidene fluoride, and polyvinylidene fluoride.

[0008] Preferably, the reinforcing polymer comprises polytetrafluoroethylene.

[0009] Preferably, the mass ratio of the molten fluoropolymer material to the reinforcing polymer is 9 to 999:1.

[0010] Preferably, the in-situ fiberization temperature is 190–280°C and the time is 5–30 min;

[0011] The in-situ fiberization is carried out under the action of a rotor, the rotor speed being 10-100 r / min.

[0012] Preferably, after in-situ fiberization, the mixture is further cooled and then granulated and dried to obtain the in-situ fiber-reinforced polymer material.

[0013] The present invention also provides an in-situ fiber-reinforced polymer material prepared by the preparation method described above, comprising a fluoropolymer material and reinforcing polymer microfibers dispersed in the fluoropolymer material.

[0014] The present invention also provides a method for preparing a separator membrane, wherein the in-situ fiber-reinforced polymer material described in the above scheme is formed into a film to obtain the separator membrane.

[0015] Preferably, the film-forming method includes casting.

[0016] Preferably, the casting conditions include: the temperature of the casting screw is 170-300°C, the die temperature is 190-300°C, and the traction speed is 40-70 m / min.

[0017] To achieve the above-mentioned objectives, the present invention provides the following technical solution:

[0018] This invention provides an in-situ fiber-reinforced polymer material and its preparation method, comprising the following steps: in-situ fiberizing a reinforcing polymer in a highly elastic state within a molten fluoropolymer to obtain the in-situ fiber-reinforced polymer material. The microfibers generated by the in-situ fiberization of the reinforcing polymer in this invention improve the mechanical properties of the in-situ fiber-reinforced polymer material. Furthermore, the microfibers obtained by in-situ fiberization exhibit good compatibility and uniform dispersion with the fluoropolymer material, further enhancing the mechanical properties of the in-situ fiber-reinforced polymer material. Consequently, the separator membrane prepared from the in-situ fiber-reinforced polymer material possesses excellent mechanical properties. Attached Figure Description

[0019] Figure 1 The Hacker rheometer test curves are for the isolation membrane of Comparative Example 1 and the isolation membrane of Example 3;

[0020] Figure 2 The Hacker rheometer test curves are for the isolation membrane of Comparative Example 2 and the isolation membrane of Example 8;

[0021] Figure 3 Here is a SEM image of the separator in Comparative Example 1;

[0022] Figure 4 Here is a SEM image of the separator membrane from Example 4;

[0023] Figure 5 Here is a SEM image of the separator in Comparative Example 2;

[0024] Figure 6 Here is a SEM image of the injection molded part from Example 10;

[0025] Figure 7 The tensile test results and actual images of the injection-molded specimens of Comparative Example 3 and Example 5 at the time of fracture are shown.

[0026] Figure 8 The tensile test results and actual images of the injection-molded specimens of Comparative Example 4 and Example 10 at the point of fracture are shown.

[0027] Figure 9 The mechanical properties of Comparative Example 2 and Example 8 before and after thermal aging are shown. Detailed Implementation

[0028] This invention provides a method for preparing in-situ fiber-reinforced polymer materials, comprising the following steps:

[0029] The in-situ fiber-reinforced polymer material is obtained by in-situ fiberizing the reinforcing polymer in a highly elastic state in a molten fluoropolymer.

[0030] The reinforcing polymer is in a highly elastic state at the in-situ fiberization temperature.

[0031] In this invention, the method for preparing the molten fluoropolymer material preferably includes the following steps:

[0032] The fluoropolymer material is dried and then melted.

[0033] The present invention does not have any particular limitation on the drying process; drying to a moisture content of <0.01% is sufficient. The melting process is preferably carried out in an internal mixer, with the speed of the mixer preferably being 10–100 r / min, more preferably 20–80 r / min, and even more preferably 40–60 r / min. The melting time is preferably 5–30 min, more preferably 15–25 min, and even more preferably 18–20 min. The melting temperature is preferably 190–280 °C, more preferably 200–250 °C, and even more preferably 220–230 °C.

[0034] In this invention, the method for preparing the highly elastic reinforced polymer preferably includes: mixing the reinforced polymer with molten fluoropolymer material to obtain the highly elastic reinforced polymer. The reinforced polymer is in a highly elastic state at the melting temperature.

[0035] In this invention, the polytetrafluoroethylene (PTFE) is preferably dried before mixing the reinforcing polymer with the molten fluoropolymer material. There are no particular limitations on the drying process; drying to a moisture content of <0.01% is sufficient.

[0036] In this invention, the mass ratio of the molten fluoropolymer material to the reinforcing polymer is 9 to 999:1, more preferably 50 to 100:1, and even more preferably 60 to 90:1; the fluoropolymer material preferably includes one or more of ethylene-tetrafluoroethylene copolymer, perfluoroethylene-propylene copolymer, vinylidene fluoride, and polyvinylidene fluoride; the reinforcing polymer preferably includes polytetrafluoroethylene.

[0037] In this invention, the in-situ fiberization temperature is preferably 190–280°C, more preferably 200–250°C, and even more preferably 220–230°C; the time is preferably 5–30 min, more preferably 15–25 min, and even more preferably 18–20 min; the in-situ fiberization is preferably carried out under the action of a rotor, the rotor speed is preferably 10–100 r / min, more preferably 20–80 r / min, and even more preferably 40–60 r / min. The shear force provided by the rotor enables the reinforcing polymer in a highly elastic state to achieve microfibrilation.

[0038] In this invention, after in-situ fiberization, the resulting mixture is preferably cooled and then granulated and dried to obtain the in-situ fiber-reinforced polymer material. In this invention, the particle size of the in-situ fiber-reinforced polymer material is preferably less than 10 mm. This invention does not impose any special limitations on the drying process; drying to a moisture content of <0.01% is sufficient.

[0039] The present invention also provides an in-situ fiber-reinforced polymer material prepared by the preparation method described above, comprising a fluoropolymer material and reinforcing polymer microfibers dispersed in the fluoropolymer material.

[0040] The present invention also provides a method for preparing a separator membrane, wherein the in-situ fiber-reinforced polymer material described in the above scheme is formed into a film to obtain the separator membrane.

[0041] In this invention, the film-forming method preferably includes casting, which preferably includes: feeding the granulated particles into the barrel of a spiral plastic extruder, and under the action of the forward thrust of the screw, extruding them from the casting die, cooling, and drawing them to form a film.

[0042] In this invention, the casting conditions include: the temperature of the casting screw is preferably 170-300°C, more preferably 200-280°C, and even more preferably 220-240°C; the die temperature is preferably 190-300°C, more preferably 200-280°C, and even more preferably 220-240°C; and the traction speed is preferably 40-70 m / min, more preferably 50-60 m / min.

[0043] The following detailed description, in conjunction with embodiments, illustrates the in-situ fiber-reinforced polymer material and its preparation method, as well as the preparation method of the separator membrane provided by the present invention. However, these descriptions should not be construed as limiting the scope of protection of the present invention.

[0044] Example 1

[0045] (1) Place 99.9% ETFE and 0.1% PTFE in an oven at 120℃ and dry for 12 hours, controlling the moisture content to be <0.01%.

[0046] (2) In-situ fiberization: First, place ETFE in a mixer and rotate it for 5 minutes at 270°C and 30 r / min to completely melt it. Then, add PTFE and continue to perform in-situ fiberization of PTFE at 270°C and 30 r / min for 15 minutes.

[0047] (3) Granulation: After the in-situ fiber-reinforced polymer material is taken out of the internal mixer and cooled to room temperature, it is put into the crusher for crushing. The preferred in-situ fiberized particles after crushing are less than 10 mm in diameter.

[0048] (4) Drying: The granulated in-situ microfibrillated particles are dried in an oven at 120℃ for 12h, and the moisture content is controlled to be <0.01%.

[0049] (5) Casting: In-situ microfibrillated granules are fed into the barrel of a screw plastic extruder. Under the forward thrust of the screw, they are extruded from the casting die, cooled, and drawn into a film with a thickness of 25 μm. The screw temperature is set to 170℃, 190℃, 230℃, 270℃, 270℃, and 270℃, the die temperature is set to 270℃, and the drawing speed is 55 m / min.

[0050] Example 2

[0051] (1) Drying: Place 99% ETFE and 1% PTFE in an oven at 120℃ and dry for 12 hours, controlling the moisture content to be <0.01%.

[0052] (2) In-situ fiberization: First, place ETFE in a mixer. At 260℃, the rotor speed is 50r / min. After rotating for 5 minutes to make it completely melt, add PTFE and continue to carry out in-situ fiberization of PTFE at 260℃ and 50r / min for 15 minutes.

[0053] (3) Granulation: After the in-situ fiber-reinforced polymer material is taken out of the internal mixer and cooled to room temperature, it is put into the crusher for crushing. The preferred in-situ fiberized particles after crushing are less than 10 mm in diameter.

[0054] (4) Drying: The granulated in-situ microfibrillated particles are dried in an oven at 120℃ for 12h, and the moisture content is controlled to be <0.01%.

[0055] (5) Casting: In-situ microfibrillated granules are fed into the barrel of a screw plastic extruder. Under the forward thrust of the screw, the granules are extruded from the casting die, cooled, and drawn into a film with a thickness of 25 μm. The screw temperature is set to 170℃, 190℃, 230℃, 260℃, 260℃, and 260℃, the die temperature is set to 260℃, and the drawing speed is 55 m / min.

[0056] Example 3

[0057] (1) Drying: Place 97% ETFE and 3% PTFE in an oven at 120℃ and dry for 12 hours, controlling the moisture content to be <0.01%.

[0058] (2) In-situ fiberization: First, place ETFE in a mixer. At 260℃, the rotor speed is 50r / min. After rotating for 5 minutes to make it completely melt, add PTFE and continue to carry out in-situ fiberization of PTFE at 260℃ and 50r / min for 15 minutes.

[0059] (3) Granulation: After the in-situ fiber-reinforced polymer material is taken out of the internal mixer and cooled to room temperature, it is put into the crusher for crushing. The preferred in-situ fiberized particles after crushing are less than 10 mm in diameter.

[0060] (4) Drying: The granulated in-situ microfibrillated particles are dried in an oven at 120℃ for 12h, and the moisture content is controlled to be <0.01%.

[0061] (5) Casting: In-situ microfibrillated granules are fed into the barrel of a screw plastic extruder. Under the forward thrust of the screw, the granules are extruded from the casting die, cooled, and drawn into a film with a thickness of 25 μm. The screw temperature is set to 170℃, 190℃, 230℃, 260℃, 260℃, and 260℃, the die temperature is set to 260℃, and the drawing speed is 55 m / min.

[0062] Example 4

[0063] (1) Drying: Place 97% ETFE and 3% PTFE in an oven at 120℃ and dry for 12 hours, controlling the moisture content to be <0.01%.

[0064] (2) In-situ fiberization: First, place ETFE in a mixer at 260°C and a rotor speed of 30 r / min. After 5 min of complete melting, add PTFE and continue in-situ fiberization of PTFE at 260°C and a speed of 30 r / min for 30 min.

[0065] (3) Granulation: After the in-situ fiber-reinforced polymer material is taken out of the internal mixer and cooled to room temperature, it is put into the crusher for crushing. The preferred in-situ fiberized particles after crushing are less than 10 mm in diameter.

[0066] (4) Drying: The granulated in-situ microfibrillated particles are dried in an oven at 120℃ for 12h, and the moisture content is controlled to be <0.01%.

[0067] (5) Casting: In-situ microfibrillated granules are fed into the barrel of a screw plastic extruder. Under the forward thrust of the screw, the granules are extruded from the casting die, cooled, and drawn into a film with a thickness of 25 μm. The screw temperature is set to 170℃, 190℃, 230℃, 260℃, 260℃, and 260℃, the die temperature is set to 260℃, and the drawing speed is 55 m / min.

[0068] Example 5

[0069] (1) Drying: Place 94% ETFE and 6% PTFE in an oven at 120℃ and dry for 12 hours, controlling the moisture content to be <0.01%.

[0070] (2) In-situ fiberization: First, place ETFE in a mixer and rotate it for 5 minutes at 270°C and 30 r / min to completely melt it. Then, add PTFE and continue to perform in-situ fiberization of PTFE at 270°C and 30 r / min for 15 minutes.

[0071] (3) Granulation: After the in-situ fiber-reinforced polymer material is taken out of the internal mixer and cooled to room temperature, it is put into the crusher for crushing. The preferred in-situ fiberized particles after crushing are less than 10 mm in diameter.

[0072] (4) Drying: The granulated in-situ microfibrillated particles are dried in an oven at 120℃ for 12h, and the moisture content is controlled to be <0.01%.

[0073] (5) Injection molding: The in-situ microfibrillated particles are placed in the heated inner cavity and injected into the dumbbell-shaped mold under the thrust of the injection screw. After cooling to room temperature, the 2mm thick injection molded part is removed from the mold. The injection temperature is set to 270℃.

[0074] Example 6

[0075] (1) Drying: Place 99.9% FEP and 0.1% PTFE in an oven at 120℃ and dry for 12 hours, controlling the moisture content to be <0.01%.

[0076] (2) In-situ fiberization: First, place FEP in a mixer at 280℃ and the rotor speed is 30r / min. After rotating for 5 minutes to make it completely melt, add PTFE and continue to carry out in-situ fiberization of PTFE at 280℃ and 30r / min for 15 minutes.

[0077] (3) Granulation: After the in-situ fiber-reinforced polymer material is taken out of the internal mixer and cooled to room temperature, it is put into the crusher for crushing. The preferred in-situ fiberized particles after crushing are less than 10 mm in diameter.

[0078] (4) Drying: The granulated in-situ microfibrillated particles are dried in an oven at 120℃ for 12h, and the moisture content is controlled to be <0.01%.

[0079] (5) Casting: In-situ microfibrillated granules are fed into the barrel of a screw plastic extruder. Under the forward thrust of the screw, they are extruded from the casting die, cooled, and drawn into a film with a thickness of 25 μm. The screw temperature is set to 180℃, 200℃, 240℃, 280℃, 280℃, and 280℃, the die temperature is set to 280℃, and the drawing speed is 60 m / min.

[0080] Example 7

[0081] (1) Drying: Place 99% FEP and 1% PTFE by mass in an oven at 120℃ and dry for 12 hours, controlling the moisture content to be <0.01%.

[0082] (2) In-situ fiberization: First, place ETFE in a mixer at 270°C and rotate the rotor at 50 r / min for 5 min until it is completely melted. Then, add PTFE and continue to perform in-situ fiberization of PTFE at 270°C and 50 r / min for 15 min.

[0083] (3) Granulation: After the in-situ fiber-reinforced polymer material is taken out of the internal mixer and cooled to room temperature, it is put into the crusher for crushing. The preferred in-situ fiberized particles after crushing are less than 10 mm in diameter.

[0084] (4) Drying: The granulated in-situ microfibrillated particles are dried in an oven at 120℃ for 12h, and the moisture content is controlled to be <0.01%.

[0085] (5) Casting: In-situ microfibrillated granules are fed into the barrel of a screw plastic extruder. Under the forward thrust of the screw, they are extruded from the casting die, cooled, and drawn into a film with a thickness of 25 μm. The screw temperature is set to 170℃, 190℃, 230℃, 270℃, 270℃, and 270℃, the die temperature is set to 270℃, and the drawing speed is 60 m / min.

[0086] Example 8

[0087] (1) Drying: Place 97% FEP and 3% PTFE by mass in an oven at 120℃ and dry for 12 hours, controlling the moisture content to be <0.01%.

[0088] (2) In-situ fiberization: First, place FEP in a mixer at 270°C and rotate the rotor at 50 r / min for 5 min until it is completely melted. Then, add PTFE and continue to perform in-situ fiberization of PTFE at 270°C and 50 r / min for 15 min.

[0089] (3) Granulation: After the in-situ fiber-reinforced polymer material is taken out of the internal mixer and cooled to room temperature, it is put into the crusher for crushing. The preferred in-situ fiberized particles after crushing are less than 10 mm in diameter.

[0090] (4) Drying: The granulated in-situ microfibrillated particles are dried in an oven at 120℃ for 12h, and the moisture content is controlled to be <0.01%.

[0091] (5) Casting: In-situ microfibrillated granules are fed into the barrel of a screw plastic extruder. Under the forward thrust of the screw, they are extruded from the casting die, cooled, and drawn into a film with a thickness of 25 μm. The screw temperature is set to 170℃, 190℃, 230℃, 270℃, 270℃, and 270℃, the die temperature is set to 270℃, and the drawing speed is 60 m / min.

[0092] Example 9

[0093] (1) Drying: Place 97% FEP and 3% PTFE by mass in an oven at 120℃ and dry for 12 hours, controlling the moisture content to be <0.01%.

[0094] (2) In-situ fiberization: First, place ETFE in a mixer and rotate it for 5 minutes at 270°C and 30 r / min to completely melt it. Then, add PTFE and continue to perform in-situ fiberization of PTFE at 270°C and 30 r / min for 30 minutes.

[0095] (3) Granulation: After the in-situ fiber-reinforced polymer material is taken out of the internal mixer and cooled to room temperature, it is put into the crusher for crushing. The preferred in-situ fiberized particles after crushing are less than 10 mm in diameter.

[0096] (4) Drying: The granulated in-situ microfibrillated particles are dried in an oven at 120℃ for 12h, and the moisture content is controlled to be <0.01%.

[0097] (5) Casting: In-situ microfibrillated granules are fed into the barrel of a screw plastic extruder. Under the forward thrust of the screw, they are extruded from the casting die, cooled, and drawn into a film with a thickness of 25 μm. The screw temperature is set to 170℃, 190℃, 230℃, 270℃, 270℃, and 270℃, the die temperature is set to 270℃, and the drawing speed is 60 m / min.

[0098] Example 10

[0099] (1) Drying: Place 94% FEP and 6% PTFE by mass in an oven at 120℃ and dry for 12 hours, controlling the moisture content to be <0.01%.

[0100] (2) In-situ fiberization: First, place ETFE in a mixer at 280°C and a rotor speed of 30 r / min. After 5 min of complete melting, add PTFE and continue in-situ fiberization of PTFE at 280°C and a speed of 30 r / min for 15 min.

[0101] (3) Granulation: After the in-situ fiber-reinforced polymer material is taken out of the internal mixer and cooled to room temperature, it is put into the crusher for crushing. The preferred in-situ fiberized particles after crushing are less than 10 mm in diameter.

[0102] (4) Drying: The granulated in-situ microfibrillated particles are dried in an oven at 120℃ for 12h, and the moisture content is controlled to be <0.01%.

[0103] (5) Injection Molding: The in-situ microfibrillated particles are placed in the heated inner cavity and injected into the dumbbell-shaped mold under the thrust of the injection screw. After cooling to room temperature, the 2mm thick injection molded part is removed from the mold. The injection temperature is set to 280℃.

[0104] Comparative Example 1

[0105] (1) Drying: Place 100% ETFE in an oven at 120℃ and dry for 12 hours, controlling the moisture content to be <0.01%.

[0106] (2) Melting: First, place ETFE in a mixer at 260°C and rotate the rotor at 50 r / min for 5 minutes to completely melt it.

[0107] (3) Granulation: After the ETFE material is taken out of the internal mixer and cooled to room temperature, it is put into the crusher for crushing. The preferred ETFE particles after crushing are less than 10mm in diameter.

[0108] (4) Drying: Dry the granulated ETFE particles in an oven at 120℃ for 12 hours, and control the moisture content to be <0.01%.

[0109] (5) Casting: ETFE granules are fed into the barrel of a screw plastic extruder. Under the forward thrust of the screw, the granules are extruded from the casting die, cooled, and drawn into a film with a thickness of 25 μm. The screw temperature is set to 170℃, 190℃, 230℃, 260℃, 260℃, and 260℃, the die temperature is set to 260℃, and the drawing speed is 55 m / min.

[0110] Comparative Example 2

[0111] (1) Drying: Place 100% FEP by mass in an oven at 120℃ and dry for 12 hours, controlling the moisture content to be <0.01%.

[0112] (2) Melting: First, place FEP in an internal mixer at 270°C and rotate the rotor at 50 r / min for 5 minutes to completely melt it.

[0113] (3) Granulation: After the FEP material is taken out of the internal mixer and cooled to room temperature, it is put into the crusher for crushing. The preferred FEP particles after crushing are less than 10mm in diameter.

[0114] (4) Drying: Dry the granulated FEP particles in an oven at 120℃ for 12 hours, and control the moisture content to be <0.01%.

[0115] (5) Casting: FEP granules are fed into the barrel of a screw plastic extruder. Under the forward thrust of the screw, they are extruded from the casting die, cooled, and drawn into a film with a thickness of 25μm. The screw temperature is set to 170℃, 190℃, 230℃, 270℃, 270℃, and 270℃, the die temperature is set to 270℃, and the drawing speed is 60m / min.

[0116] Comparative Example 3

[0117] (1) Drying: Place 100% ETFE in an oven at 120℃ and dry for 12 hours, controlling the moisture content to be <0.01%.

[0118] (2) Melting: First, place ETFE in a mixer at 260°C and rotate the rotor at 50 r / min for 5 minutes to completely melt it.

[0119] (3) Granulation: After the ETFE material is taken out of the internal mixer and cooled to room temperature, it is put into the crusher for crushing. The preferred ETFE particles after crushing are less than 10mm in diameter.

[0120] (4) Drying: Dry the granulated ETFE particles in an oven at 120℃ for 12 hours, and control the moisture content to be <0.01%.

[0121] (5) Injection Molding: ETFE granules are placed in the heated inner cavity and injected into the dumbbell-shaped mold under the thrust of the injection screw. After cooling to room temperature, the 2mm thick injection molded part is removed from the mold. The injection temperature is set to 270℃.

[0122] Comparative Example 4

[0123] (1) Drying: Place 100% FEP by mass in an oven at 120℃ and dry for 12 hours, controlling the moisture content to be <0.01%.

[0124] (2) Melting: First, place FEP in an internal mixer at 260°C and rotate the rotor at 50 r / min for 5 minutes to completely melt it.

[0125] (3) Granulation: After the FEP material is taken out of the internal mixer and cooled to room temperature, it is put into the crusher for crushing. The preferred FEP particles after crushing are less than 10mm in diameter.

[0126] (4) Drying: Dry the granulated FEP particles in an oven at 120℃ for 12 hours, and control the moisture content to be <0.01%.

[0127] (5) Injection Molding: FEP granules are placed in the heated inner cavity and injected into the dumbbell-shaped mold under the thrust of the injection screw. After cooling to room temperature, the 2mm thick injection molded part is removed from the mold. The injection temperature is set to 280℃.

[0128] The formulations and in-situ fiberization process parameters of Examples 1-10 and Comparative Examples 1-2 are shown in Table 1.

[0129] Table 1. Formulations and in-situ fiberization process parameters for Examples 1-10 and Comparative Examples 1-2

[0130]

[0131] The mechanical properties of Examples 1-10 and Comparative Examples 1-4 were measured, and the results are shown in Table 2.

[0132] Table 2 Mechanical properties of materials in Examples 1-10

[0133]

[0134]

[0135] As shown in Table 2, the tensile strength and elongation at break gradually increase with the increase of PTFE ratio.

[0136] The Hacker rheometer test curves of the isolation membranes of Comparative Example 1 and Example 3 were measured, and the results are as follows: Figure 1 As shown. By Figure 1It can be seen that after the addition of PTFE, due to the in-situ microfibrillation effect of PTFE, the torque of the ETFE melt is greater than that without the addition of PTFE. Furthermore, as time goes on, the dispersion of in-situ microfibrillation improves, and the torque tends to level off.

[0137] The Hacker rheometer test curves of the isolation membranes of Comparative Example 2 and Example 8 were measured, and the results are as follows: Figure 2 As shown. By Figure 2 It can be seen that after adding PTFE, due to the in-situ microfibrillation effect of PTFE, the torque of the FEP melt is greater than that without PTFE. Furthermore, as time goes on, the dispersion of in-situ microfibrillation improves, and the torque tends to level off.

[0138] SEM analysis was performed on the separator of Comparative Example 1, and the results are as follows: Figure 3 As shown. By Figure 3 It can be seen that without in-situ microfibrillation of PTFE, the surface of ETFE is smooth.

[0139] SEM analysis was performed on the separator membrane of Example 4, and the results are as follows: Figure 4 As shown. By Figure 4 It can be seen that the addition of PTFE leads to in-situ microfibrillation, and fibrous material begins to appear on the surface of ETFE.

[0140] SEM analysis was performed on the separator of Comparative Example 2, and the results are as follows: Figure 5 As shown. By Figure 5 It can be seen that without in-situ microfibrillation of PTFE, the surface of FEP is smooth.

[0141] SEM analysis was performed on the injection molded part of Example 10, and the results are as follows: Figure 6 As shown. By Figure 6 It can be seen that the addition of PTFE leads to in-situ microfibrillation, and fibrous material begins to appear on the surface of FEP.

[0142] Tensile tests were conducted on the injection molded parts of Comparative Example 3 and Example 5. The results and actual images of the fractured parts are shown below. Figure 7 As shown. By Figure 7 It can be seen that after the in-situ microfiberization of PTFE, the tensile strength and elongation at break of the ETFE standard injection molded parts are improved.

[0143] Tensile tests were conducted on the injection molded parts of Example 4 and Example 10. The results and actual images of the fractured parts are shown below. Figure 8 As shown. By Figure 8 It can be seen that after the in-situ microfiberization of PTFE, the tensile strength and elongation at break of the FEP standard injection molded parts are improved.

[0144] The mechanical properties of the separators in Comparative Example 2 and Example 8 before and after thermal aging were measured, and the results are as follows: Figure 9 As shown. By Figure 9 It can be seen that after in-situ microfibrillation of PTFE, the tensile strength and elongation at break of both ETFE and FEP separator membranes are improved compared with those without in-situ microfibrillation of PTFE.

[0145] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for producing an isolating film, characterized by, Forming a film of the in-situ fiber reinforced polymer material to obtain the release film; The preparation method of the in-situ fiber reinforced polymer material comprises the following steps: carrying out in-situ fiberization of the reinforcing polymer in a molten fluoropolymer, and then carrying out granulation and drying after cooling to obtain the in-situ fiber reinforced polymer material; the fluoropolymer is ETFE; the reinforcing polymer is in an elastomeric state at the melting temperature of the fluoropolymer; the reinforcing polymer is PTFE; the in-situ fiberization is carried out under the action of a rotor; the temperature of the in-situ fiberization is 190-260 ℃.

2. The production method according to claim 1, characterized by, the mass ratio of the molten fluoropolymer material to the reinforcing polymer is 9-999:

1.

3. The preparation method according to claim 1, characterized in that, the time of the in-situ fiberization is 5-30 min; the in-situ fiberization is carried out under the action of a rotor, and the rotating speed of the rotor is 10-100 r / min.

4. The method of claim 1, wherein, the film forming mode comprises casting.

5. The preparation method according to claim 4, characterized in that, the casting conditions comprise that the temperature of a casting screw is 170-300 ℃, the temperature of a die is 190-300 ℃, and the pulling speed is 40-70 m / min.

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