Method for manufacturing porous polymer membrane

Abstract

This invention provides a method for manufacturing a porous polymer membrane. According to the method for manufacturing the porous polymer membrane, a vacuum index I defined by the following formula 1 is used. V The immersion index I is defined by the following formula 2. L and the inhalation index I defined by the following formula 3 S Any of these methods can control the degree to which oxygen is removed from the pores of the primary porous membrane. Therefore, side reactions caused by oxygen during electron beam crosslinking can be suppressed or reduced, thereby improving the chemical and physical properties and mechanical and physical properties of the manufactured porous polymer membrane. [Equation 1] I V =(V2 / V1)×(1 / 100)[Formula 2] I L =L2 / L1[Equation 3] I S =(S1×S2) / 100

Description

Technical Field

[0001] This invention relates to a method for manufacturing a porous polymer membrane. Background Technology

[0002] Porous polymer membranes are used in various industrial fields due to their micropores and low reactivity. For example, porous polymer membranes can be used as battery separators, gas separation processes and devices, reverse osmosis separation membranes, etc., and can perform functions such as physical or electrical separation and preventing remixing of purified products.

[0003] In recent years, there has been an increasing demand for porous polymer membranes that can maintain high durability even in extreme environments. For example, there is growing interest in whether porous polymer membranes can maintain their performance under conditions such as extremely high temperatures, extremely low temperatures, electrostatically induced environments, high loads, or applied external forces.

[0004] For example, technologies are being proposed to improve the durability of porous polymer membranes through surface treatment, post-processing, and other methods. Summary of the Invention

[0005] (a) Technical problems to be solved One technical problem of the present invention is to provide a method for manufacturing a porous polymer membrane with improved chemical and mechanical properties.

[0006] (II) Technical Solution A method for manufacturing a porous polymer membrane according to an embodiment of the present invention may include preparing a vacuum atmosphere chamber including an electron beam irradiation section at the rear end of a chamber; and adding a first A primary porous membrane into the vacuum atmosphere chamber, wherein the first A primary porous membrane can satisfy a vacuum index I defined by the following formula 1. V The vacuum atmosphere chamber is filled with gases ranging from 0.1 to 3000.

[0007] [Formula 1] I V =(V2 / V1)×(1 / 100) In Equation 1, V1 represents the vacuum level (torr) in the vacuum atmosphere chamber, and V2 represents the travel time (sec) of the membrane after the first A primary porous membrane is added to the vacuum atmosphere chamber until it is irradiated by the electron beam by the electron beam irradiation unit.

[0008] In one implementation, V1 in Equation 1 can be 1.0 × 10 -6 Up to 7.6×10 2 Entrust.

[0009] In one implementation, V2 in Formula 1 can be from 1 second to 180 seconds.

[0010] In one embodiment, the manufacturing method may further include irradiating the first A primary porous membrane with an electron beam in the electron beam irradiation section.

[0011] In one embodiment, the first A primary porous membrane can be wound in the electron beam irradiation section, and the wound first A primary porous membrane can be irradiated with an electron beam.

[0012] A method for manufacturing a porous polymer membrane according to an embodiment of the present invention includes adding a first B primary porous membrane into a liquid processing chamber filled with a non-reactive liquid or sprayed with a non-reactive liquid, wherein the first B primary porous membrane can satisfy an impregnation index I defined by the following formula 2. L The liquid is passed through the liquid processing chamber under conditions where the concentration is 0.8 or higher.

[0013] [Equation 2] I L =L2 / L1 In Equation 2, L1 represents the surface tension (mN / m) of the non-reactive liquid, and L2 represents the surface energy (mN / m) of the first B primary porous membrane.

[0014] In one implementation, L1 in Equation 2 can be below 80 mN / m.

[0015] In one implementation, L2 in Equation 2 can be below 80 mN / m.

[0016] In one implementation, the absolute value of the difference between L1 and L2 in Equation 2 (┃L2-L1┃) can be below 20mN / m.

[0017] When discharged from the liquid treatment chamber, the porous membrane thus treated can be obtained as a second primary porous membrane.

[0018] In one embodiment, the non-reactive liquid may contain one or more organic solvents selected from those with a boiling point above 40°C.

[0019] In one embodiment, the non-reactive liquid may include at least one selected from propylene glycol, n-hexane, n-heptane, n-octane, n-nonane, cyclohexane, methylcyclohexane, toluene, xylene, ethylbenzene, ethyl acetate, butyl acetate, isobutyl acetate, sec-butyl acetate, diisopropyl ether, dimethyl carbonate, isopropyl acetate, methyl isobutyl ketone, methyl ethyl ketone, acetone, chloroform, diethyl carbonate, benzyl alcohol, butanol, propanol, pentanol, methanol, ethanol, and isopropanol.

[0020] In one embodiment, the manufacturing method may further include irradiating a second B primary porous membrane discharged from the liquid processing chamber with an electron beam.

[0021] In one embodiment, the primary porous membrane irradiated with an electron beam may be performed within 60 seconds after the primary porous membrane is discharged from the liquid processing chamber.

[0022] In one embodiment, the second primary porous membrane can be wound in the electron beam irradiation section, and the wound second primary porous membrane can be irradiated with an electron beam.

[0023] In one embodiment, electron beam irradiation of the second primary porous membrane can be performed in an inert gas atmosphere chamber.

[0024] In one embodiment, the manufacturing method may further include adding the second primary porous membrane into the liquid processing chamber more than once before irradiating the second primary porous membrane with an electron beam.

[0025] A method for manufacturing a porous polymer membrane according to an embodiment of the present invention includes preparing an inert gas atmosphere chamber comprising an intake roller at a front end and an electron beam irradiation section at a rear end; adding a first C primary porous membrane into the inert gas atmosphere chamber, wherein the first C primary porous membrane can satisfy an intake index I defined by the following formula 3. S It travels on the suction roller under conditions of 1 or higher.

[0026] [Formula 3] I S =(S1×S2) / 100 In Equation 3, S1 represents the suction pressure (mmAq) of the suction roller, and S2 represents the time (seconds) required for the first C primary porous membrane to travel on the suction roller.

[0027] In one implementation, S1 in Formula 3 can be below 5000 mmAq.

[0028] In one implementation, S2 in Formula 3 can be from 0.1 seconds to 20 seconds.

[0029] In one embodiment, the manufacturing method may further include irradiating the first C primary porous membrane with an electron beam in the electron beam irradiation section.

[0030] In one embodiment, the primary porous membrane can be irradiated with an electron beam within 60 seconds of the first C primary porous membrane passing through the suction roller.

[0031] In one embodiment, the first C primary porous membrane can be wound in the electron beam irradiation section, and the wound first C primary porous membrane can be irradiated with an electron beam.

[0032] (III) Beneficial Effects The method for manufacturing a porous polymer membrane according to an embodiment of the present invention can prevent or reduce side reactions that may be caused by oxygen during the crosslinking process.

[0033] Therefore, the chemical and mechanical properties of the manufactured porous polymer membrane can be improved. For example, the solvent resistance and heat resistance of the porous polymer membrane can be improved. Attached Figure Description

[0034] Figure 1 This is a schematic process flow diagram illustrating a method for manufacturing a porous polymer membrane according to one embodiment of the present invention.

[0035] Figure 2 This is a schematic process flow diagram illustrating a method for manufacturing a porous polymer membrane according to one embodiment of the present invention.

[0036] Figure 3 This is a schematic process flow diagram illustrating a method for manufacturing a porous polymer membrane according to one embodiment of the present invention.

[0037] Figure 4 This is a schematic process block diagram illustrating a method for manufacturing a porous polymer membrane according to one embodiment of the present invention.

[0038] Figure 5 This is a schematic process block diagram illustrating a method for manufacturing a porous polymer membrane according to one embodiment of the present invention.

[0039] Figure 6 This is a schematic process block diagram illustrating a method for manufacturing a porous polymer membrane according to one embodiment of the present invention.

[0040] Figure 7 This is a schematic process block diagram illustrating a method for manufacturing a porous polymer membrane according to one embodiment of the present invention.

[0041] Figure 8 This is a schematic diagram of a manufacturing system for a porous polymer membrane according to an exemplary embodiment.

[0042] Figure 9 This is a schematic diagram illustrating the direction used to explain the process of measuring cumulative exposure in Example 9-1.

[0043] Figure 10 This is a schematic diagram illustrating the direction used to explain the process of measuring cumulative exposure in Embodiment 9-2.

[0044] Figure 11 A schematic diagram illustrating the direction used to explain the process of measuring cumulative exposure in Reference Examples 1-1 and 1-2 is shown as an example. Detailed Implementation

[0045] The following detailed description of exemplary embodiments of the present invention, with reference to the accompanying drawings, enables those skilled in the art to readily implement the invention. However, this is merely exemplary, and the present invention is not limited to the exemplary embodiments described.

[0046] <Methods for Manufacturing Porous Polymer Membranes> Figure 1 This is a schematic process flow diagram illustrating a method for manufacturing a porous polymer membrane according to one embodiment of the present invention.

[0047] A method for manufacturing a porous polymer membrane according to one embodiment of the present invention includes: preparing a vacuum atmosphere chamber including an electron beam irradiation section at the rear end of the chamber (step S10A); and adding a first A primary porous membrane into the vacuum atmosphere chamber (step S20A), wherein the first A primary porous membrane can satisfy a vacuum index I defined by the following formula 1. V The vacuum atmosphere chamber is filled with gases ranging from 0.1 to 3000.

[0048] [Formula 1] I V =(V2 / V1)×(1 / 100) In Equation 1, V1 represents the vacuum level (Torque) in the vacuum atmosphere chamber, and V2 represents the travel time (seconds) of the membrane after the first A primary porous membrane is added to the vacuum atmosphere chamber until it is irradiated by the electron beam through the electron beam irradiation unit.

[0049] Therefore, oxygen present inside the pores of the first A primary porous membrane can be effectively removed, thereby effectively preventing or inhibiting side reactions caused by oxygen in the subsequent crosslinking process.

[0050] For example, oxygen can capture and consume free radicals generated during the crosslinking process, potentially reducing the efficiency of the crosslinking reaction. Furthermore, free radicals can undergo oxidative decomposition reactions with oxygen, potentially generating peroxy free radicals that induce side reactions, and oxidative byproducts may also be produced. In such cases, the mechanical strength and / or thermal stability of the manufactured polymer film may be reduced.

[0051] According to one embodiment of the present invention, a method for manufacturing a porous polymer membrane can prevent or reduce the above-mentioned phenomena, thereby simultaneously improving the chemical and mechanical properties of the porous polymer membrane.

[0052] As a non-limiting example, the vacuum atmosphere chamber can refer to a device that maintains a low-oxygen or gas-free state in the internal space by creating a pressure inside the chamber that is lower than the external atmospheric pressure, such as being connected to a vacuum pump, valve, etc.

[0053] In some implementation schemes, I V The values ​​can be 0.1 to 3000, 0.5 to 2500, 1 to 1500, 1 to 1000, 1 to 900, 1 to 700, 1 to 500, 1 to 300, or 2 to 300.

[0054] Therefore, oxygen present in the pores of the first A primary porous membrane can be effectively removed.

[0055] In one implementation, V1 in Equation 1 can be 1.0 × 10 -6 Up to 7.6×10 2 For example, the value could be 1.0 × 10. -3 Up to 1.0×10 -1 Therefore, it can prevent deformation of the primary porous membrane 1A and effectively remove oxygen present in its pores.

[0056] In one embodiment, V2 in Formula 1 can be from 1 second to 180 seconds, for example, from 10 seconds to 120 seconds. Therefore, the overall efficiency of the manufacturing method can be improved, and oxygen present in the pores of the first A primary porous membrane can be sufficiently removed.

[0057] In one embodiment, the manufacturing method may further include irradiating the first A primary porous film with an electron beam in the electron beam irradiation section (step S30A).

[0058] Crosslinking reactions can be carried out by irradiating a primary porous membrane (I-A) with an electron beam to remove at least 80% of the oxygen in the pores. This can prevent the consumption of free radicals caused by oxygen and inhibit or reduce the formation of byproducts.

[0059] The first A primary porous membrane is not particularly limited as long as it can be cured by electron beam irradiation. For example, it may include polyolefin-based resins such as polyethylene, polypropylene, and polymethylpentene; polyesters such as nylon and polyethylene terephthalate; polycarbonate; styrene-based resins; fluorine-based resins such as polytetrafluoroethylene and polyvinylidene fluoride; and vinyl chloride resins. These can be used alone or in combination of two or more.

[0060] In one embodiment, the first A primary porous membrane may comprise polyethylene (PE), polypropylene (PP), polybutene, polypentene, polymethylpentene, polyvinylidene fluoride (PVDF), polyvinylidene fluoride-hexafluoropropylene (PVDF-HFP), polyvinylidene fluoride-chlorotrifluoroethylene (PVDF-CTFE), polyvinylidene fluoride-ethylene tetrafluoroethylene (PVDF-ETFE), polyacrylonitrile (PAN), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyethylene naphthalate (PEN), polyimide (PI), polyphenylene sulfide (PPS), polysulfone, polyethersulfone (PES), ethylene vinyl acetate (EVA), and / or polycarbonate (PC).

[0061] The polyolefin-based resin may include polypropylene-based resin, polyethylene-based resin, etc.

[0062] In one embodiment, the manufacturing method may further include forming the first primary porous membrane by extruding or extruding and stretching a polymer-containing raw material.

[0063] As a non-limiting example, the extrusion and stretching apparatus may include dies such as T-die heads, and may use single-axis or biaxial stretching apparatus such as tenter frame equipment.

[0064] As a non-limiting example, the polymer-containing raw material may be provided in the form of granules or melts.

[0065] As a non-limiting example, an extruder can be used to extrude and cool granular raw materials at a temperature above 200°C to form unstretched resin sheets, and the unstretched sheets can be stretched to form the first A primary porous membrane. The stretching method may include simultaneous biaxial stretching, successive biaxial stretching, multi-segment stretching, multiple stretching, etc.

[0066] In one embodiment, the thickness of the first A primary porous membrane can be less than 200 μm, for example, it can be 5 μm to 50 μm, 5 μm to 30 μm or 5 μm to 20 μm.

[0067] In one embodiment, the porosity of the first A primary porous membrane can be from 10% to 80%, for example, from 30% to 60% or from 35% to 55%.

[0068] The porosity of the first primary porous membrane can be obtained, for example, by calculating the internal space (pore volume ratio) of the membrane.

[0069] The porosity of the membrane can be measured, for example, by mass- and size-based methods, liquid permeation methods, etc.

[0070] As a non-limiting example, in the mass- and size-based method, porosity can be calculated as follows: First, a membrane sample is prepared. The mass, thickness, and area of ​​the sample are measured using a precision balance. The skeletal density of the polymer is measured using a device such as a helium specific gravity bottle. The measured mass of the sample is divided by the product of the thickness, area, and skeletal density to calculate the volume ratio of solids within the membrane. This volume ratio is then subtracted from the total volume (100%) to calculate the porosity (%). For example, the membrane thickness can be measured using a contact thickness gauge with an accuracy of approximately 0.1 μm. As a non-limiting example, the membrane thickness can be measured using a TESA Mu-Hite electronic height gauge from TESA, with the measurement pressure set to 0.63 N.

[0071] As a non-limiting example, in the liquid permeation method, porosity can be calculated as follows: The sample is thoroughly immersed in a solvent, allowing the solvent to permeate into the pores. The mass of the immersed sample and the mass of the dried sample can then be measured separately. The difference in mass is multiplied by the density of the solvent to calculate the volume filled in the pores. This volume is then compared with the total volume of the membrane to calculate the porosity.

[0072] In one embodiment, the pore size of the first A primary porous membrane can be less than 100 nm, for example, it can be 40 nm to 100 nm, 40 nm to 90 nm, 40 nm to 70 nm or 40 nm to 60 nm.

[0073] The pore size may refer to the average diameter of the pores. As a non-limiting example, the pore size can be measured using a pore size analyzer according to ASTM F316-03, for example, by the half-dry method. The pore size analyzer can be, for example, a capillary flow porometer, a gas adsorption analyzer (BET, BJH, etc.), or a helium pycnometer.

[0074] In one embodiment, when an electron beam is irradiated by the electron beam irradiation unit, the oxygen replacement rate of the first A primary porous membrane can be 80% or more, 90% or more, or 95% or more.

[0075] As used in this specification, "oxygen replacement rate" can refer to a percentage value representing the proportion of the total oxygen content contained within the pores of a porous membrane to the total oxygen content removed from the pores. There are no particular limitations on the method for measuring the total oxygen content. For example, when the oxygen replacement rate is calculated using the total number of moles of oxygen as the total oxygen content, the oxygen replacement rate can be a percentage value representing the proportion of the total number of moles of oxygen removed from the pores of the porous membrane to the total number of moles of oxygen contained within the pores of the porous membrane.

[0076] In one embodiment, the oxygen replacement rate can be a percentage value calculated as the ratio of the total number of moles of oxygen removed from the pores of the first A primary porous membrane when irradiated by the electron beam irradiation unit to the total number of moles of oxygen present in the pores of the first A primary porous membrane before being added to the vacuum atmosphere chamber.

[0077] There is no particular upper limit to the oxygen replacement rate; the higher the value, the more it can prevent or reduce side reactions caused by oxygen.

[0078] As a non-limiting example, the total number of moles (n) of oxygen present in the pores of the first A primary porous membrane before being added to the vacuum atmosphere chamber. I The following calculation can be performed. For example, the pores of the primary porous membrane (V1A) stored or prepared under atmospheric atmosphere before being added to the vacuum atmosphere chamber may be filled with air. The total volume (V1A) of the primary porous membrane (V1A) can be calculated as follows. F Multiply by porosity (R) P To calculate pore volume (V) P ), the pore volume (V P Substituting the atmospheric absolute pressure of approximately 101.325 kPa, the room temperature of approximately 298.15 K, and the gas constant (R) into the ideal gas law (PV=nRT), the total number of moles of gas within the pores (n) can be calculated. T At this point, no special temperature restriction is required; the temperature measured in the atmosphere in which the membrane is stored or prepared can be substituted into the ideal gas law. The total number of moles of gas within the pores (n) can then be expressed as... T Multiply by the mole fraction of oxygen in the atmosphere (n) O The value is approximately 0.21, which allows us to calculate the total number of moles of oxygen present in the pores (n). I At this point, the gas constant R is a known constant, which can be approximately 8.314 J / mol·K.

[0079] As a non-limiting example, the total number of moles (n) of oxygen removed from the pores of the first A primary porous membrane. F The following calculation can be performed.

[0080] For example, an oxygen analyzer can be installed in the vacuum atmosphere chamber to measure the increase in partial pressure of oxygen (P). O The increase in the partial pressure of oxygen (P) O ), the effective volume of the chamber (V) C The internal temperature of the chamber (T) C Substituting the gas constant (R) and the total number of moles of oxygen removed from the pores (n) into the ideal gas law, we can calculate the total number of moles of oxygen removed from the pores (n). F )".

[0081] The oxygen analyzer can be used to measure the increase in partial pressure of oxygen (P0.05). O The apparatus can also measure the partial pressure of oxygen, if needed. The oxygen analyzer can be, for example, a residual gas analyzer (RGA, mass spectrometer), a paramagnetic oxygen analyzer, a zirconia oxygen analyzer, a galvanic cell type, or other electrochemical oxygen analyzers, as long as it can measure the partial pressure of oxygen (or the increase in partial pressure over time). There are no particular limitations on the structure or materials of the apparatus. Furthermore, the oxygen partial pressure can be calculated by multiplying the oxygen concentration (volume %) and the total pressure in the chamber, and then calculating the difference from the initial partial pressure to obtain the increase in oxygen partial pressure (P0.05). O ).

[0082] The manufactured porous polymer membrane may contain the crosslinked resin of the primary porous membrane of the first A, such as crosslinked polyolefin resin, crosslinked polyester, crosslinked polycarbonate, crosslinked styrene resin, crosslinked fluoropolymer resin, crosslinked vinyl chloride resin, etc.

[0083] In one embodiment, the electron beam irradiation can be performed at an accelerating voltage of 0.1 MeV to 10 MeV. For example, the electron beam can be used for irradiation at an accelerating voltage of 0.1 MeV to 5 MeV or 0.2 MeV to 2.5 MeV. Therefore, cross-linking between polymer chains can be appropriately achieved, and polymer chain decomposition can be suppressed.

[0084] Figure 4 This is a schematic process diagram illustrating, for example, the passage of the first A primary porous membrane through the vacuum atmosphere chamber in a method for manufacturing a porous polymer membrane according to one embodiment of the present invention.

[0085] In one embodiment, the first A primary porous membrane can be transported in a roll-to-roll manner.

[0086] For example, the front end of the vacuum atmosphere chamber may include a membrane traveling section, and the rear end may include an electron beam irradiation section. For example, the traveling section and the electron beam irradiation section can be continuously connected via a roll-to-roll process, allowing the entire process to be performed continuously.

[0087] As a non-limiting example, the electron beam irradiation section may include an electron beam irradiation device, and there is no particular limitation on the type of electron beam irradiation device.

[0088] The electron beam irradiation device can be installed inside or outside the vacuum atmosphere chamber. For example, when the electron beam irradiation device is installed outside the vacuum atmosphere chamber, the electron beam can be used to irradiate the first A primary porous film traveling inside the vacuum atmosphere chamber through the electron beam penetration window.

[0089] The window through which the electron beam penetrates may be located on one side of the vacuum atmosphere chamber, for example, it may be located at the top, bottom, or side of the vacuum atmosphere chamber, for example, it may be located at the top or side of the vacuum atmosphere chamber.

[0090] As a non-limiting example, the window through which the electron beam penetrates may be formed of materials including titanium, beryllium, silicon nitride film, polyimide, boron nitride, etc., but is not limited thereto.

[0091] In one embodiment, the first A primary porous membrane may be provided in a rolled-up state and conveyed to the vacuum atmosphere chamber by unwinding.

[0092] In one embodiment, the conveyed primary porous membrane 1A can be wound back into a roll.

[0093] The unwinding can be performed by an unwinding roller, and the winding can be performed by a winding roller. For example, the first A primary porous membrane wound on the unwinding roller is unwound, and during the process of being conveyed by at least one conveying roller, it is cross-linked by the electron beam irradiation unit. The cross-linked first A primary porous membrane is then conveyed to the winding roller and wound up.

[0094] The number of conveying rollers can be adjusted considering the scale of the equipment and / or device, the size and type of the first A primary porous membrane, etc., for example, from 1 to 20, but not limited thereto.

[0095] In one embodiment, the unwinding and winding speeds can be from 10 meters per minute (mpm) to 200 meters per minute.

[0096] In one embodiment, the winding roller may be disposed outside or inside the vacuum atmosphere chamber.

[0097] In one embodiment, the winding roller may be disposed outside the vacuum atmosphere chamber, and the electron beam may be used to irradiate the first A primary porous membrane traveling within the vacuum atmosphere chamber with an electron beam.

[0098] As a non-limiting example, the unwinding roller and the winding roller may further include running parts such as motors for operating each roller, and frame parts for supporting each component.

[0099] The irradiation direction of the electron beam can be, for example, substantially perpendicular to one side of the first A primary porous membrane. In this case, the electron beam irradiation device can be controlled by taking into account factors such as the energy density and accelerating voltage of the electron beam, the diameter of the winding roller, the thickness of the primary porous polymer membrane, and the energy required for crosslinking.

[0100] In the vacuum atmosphere chamber, a porous polymer film cross-linked by electron beam irradiation can be discharged from the vacuum atmosphere chamber, conveyed to the winding roller, and wound up. The porous polymer film discharged from the vacuum atmosphere chamber can be conveyed to the winding roller and wound up under atmospheric atmosphere or an additional vacuum atmosphere. As a non-limiting example, the additional vacuum atmosphere can be an additional vacuum atmosphere chamber, etc.

[0101] In one embodiment, the first A primary porous membrane can be wound in the electron beam irradiation section, and the wound first A primary porous membrane can be irradiated with an electron beam.

[0102] In one embodiment, the winding roller may be disposed inside the vacuum atmosphere chamber, and the electron beam may be used to irradiate the first A primary porous membrane wound by the winding roller inside the vacuum atmosphere chamber with an electron beam irradiation unit.

[0103] The electron beam can be directed, for example, toward the central axis of the winding roller. Through the rotating winding roller, the porous polymer membrane can be repeatedly exposed to the electron beam. Therefore, even when irradiated with a low-energy electron beam, the first A primary porous membrane can be sufficiently crosslinked.

[0104] As a non-limiting example, the distance between the electron beam irradiation device and the central axis of the winding roller can be 10cm to 100cm or 30cm to 100cm. The distance can refer to the shortest straight-line distance between the electron beam irradiation section of the electron beam irradiation device and the surface of the winding roller.

[0105] At this point, the energy density and accelerating voltage of the electron beam, the diameter of the winding roller, the thickness of the primary porous polymer film, and the energy required for crosslinking can be considered to control the spacing of the electron beam irradiation device.

[0106] In one embodiment, the penetration depth of the electron beam can be from 0.2 mm to 7 mm.

[0107] As a non-limiting example, when the electron beam is irradiated onto the first A primary porous membrane wound through the winding roller, any region of the first A primary porous membrane can be irradiated by the electron beam 100 to 300 times.

[0108] In one embodiment, the cumulative irradiation dose of the electron beam on the porous polymer membrane can be from 10 kGy to 300 kGy. For example, the cumulative irradiation dose of the electron beam can be the average cumulative irradiation dose per unit area of ​​the porous polymer membrane. For example, the cumulative irradiation dose can be based on a single irradiation dose of the electron beam and the area (A) of any region of the first A primary porous membrane irradiated by the electron beam. rad The calculation is based on the irradiation depth and the number of passes of the electron beam.

[0109] For example, the unwinding roller and the winding roller can rotate together. For example, in the initial stage of supplying the first A primary porous membrane, the first A primary porous membrane can be fed to the winding roller by the conveying roller while only the unwinding roller rotates. The unwinding roller and the winding roller can rotate at the same speed as the first A primary porous membrane begins to be wound onto the winding roller. For example, in the later stage after all the first A primary porous membrane wound onto the unwinding roller has been supplied, only the winding roller can be rotated. For example, after all the first A primary porous membrane has been wound onto the winding roller, the winding roller can continue to rotate while irradiating the electron beam, and the additional rotation of the winding roller can be determined based on the sufficient curing of the last wound first A primary porous membrane or the cumulative irradiation amount of the electron beam.

[0110] For example, when the winding roller is disposed outside the vacuum atmosphere chamber, the single irradiation dose of the electron beam to the first A primary porous membrane traveling in the vacuum atmosphere chamber can be substantially the same as the cumulative irradiation dose.

[0111] For example, the porous polymer membrane can be formed into a roll that is wound up by the winding roller. As a non-limiting example, the diameter of the rolled porous polymer membrane can be from 10 cm to 30 cm. The diameter can refer to the diameter of the vertical cross-section of the rolled porous polymer membrane after manufacturing. The diameter of the rolled porous polymer membrane can be adjusted taking into account factors such as production scale, the thickness of the first A primary porous membrane and the energy required for curing, system equipment space, etc., and is not limited to the above range.

[0112] A method for manufacturing a porous polymer membrane according to another embodiment of the present invention may include adding a first primary porous membrane (S10B) into a liquid treatment chamber filled with a non-reactive liquid or sprayed with a non-reactive liquid, wherein the first primary porous membrane can satisfy the impregnation index I defined by the following formula 2. L The liquid is passed through the liquid processing chamber under conditions where the concentration is 0.8 or higher.

[0113] [Equation 2] I L =L2 / L1 In Equation 2, L1 represents the surface tension (mN / m) of the non-reactive liquid, and L2 represents the surface energy (mN / m) of the first B primary porous membrane.

[0114] Next, a second primary porous layer (B) can be obtained from the liquid processing chamber.

[0115] The surface tension can be measured, for example, at 25 ± 2 °C using a tensiometer employing the ring method (Du Noüy method) according to ISO 304, ASTM D1331, or equivalent standards. The surface energy can be calculated, for example, by measuring the contact angles of two or more probe liquids at 25 ± 2 °C using the Owens-Wendt-Rabel-Kaelble method according to ISO 19403 or equivalent standards.

[0116] Therefore, oxygen present inside the pores of the first primary porous membrane can be effectively removed, thereby effectively preventing or inhibiting side reactions caused by oxygen in the subsequent crosslinking process.

[0117] In some implementation schemes, I L The 0.8 to 2.0, 0.8 to 1.8, 0.8 to 1.5, 0.8 to 1.4, or 0.8 to 1.2 can be used. Therefore, oxygen present in the pores within the primary porous membrane 1B can be removed more effectively.

[0118] When the liquid processing chamber is filled with the non-reactive liquid, the liquid processing chamber can be a liquid-filled chamber. In this case, after the first B primary porous membrane is added to the liquid-filled chamber, it can be transported while immersed in the non-reactive liquid.

[0119] When a jetting device is provided in the liquid processing chamber, the liquid processing chamber can be a liquid jetting chamber. The jetting device may include a jetting nozzle, etc. In this case, after the first B primary porous membrane is added to the liquid jetting chamber, it can be transported in an environment where the non-reactive liquid is jetted.

[0120] In one embodiment, L1 in Formula 2 can be below 80 mN / m, for example, it can be from 15 mN / m to 80 mN / m, 15 mN / m to 70 mN / m, 15 mN / m to 60 mN / m, or 20 mN / m to 40 mN / m. Therefore, the permeation of the non-reactive liquid into the pores of the first B primary porous membrane can be increased.

[0121] In one embodiment, L2 in Formula 2 can be below 80 mN / m, for example, it can be from 15 mN / m to 80 mN / m, 15 mN / m to 70 mN / m, 15 mN / m to 60 mN / m, or 20 mN / m to 40 mN / m. Therefore, the permeation of the non-reactive liquid into the pores of the first B primary porous membrane can be increased.

[0122] In one embodiment, the absolute value of the difference between L1 and L2 in Equation 2 (┃L2-L1┃) can be less than 20 mN / m. ┃L2-L1┃ can, for example, be less than 15 mN / m, less than 12 mN / m, less than 10 mN / m, or 0 mN / m to 10 mN / m. Therefore, the permeation of the non-reactive liquid into the pores of the first B primary porous membrane can be improved more effectively.

[0123] In one embodiment, the non-reactive liquid may comprise one or more organic solvents selected from those with a boiling point above 40°C. Therefore, the evaporation of the non-reactive liquid that has permeated into the pores of the membrane can be prevented or reduced during the crosslinking process, which is a subsequent process.

[0124] In one embodiment, the non-reactive liquid may contain one or more organic solvents selected from those with boiling points from 40°C to 300°C.

[0125] As a non-limiting example, the non-reactive liquid may include propylene glycol, n-hexane, n-heptane, n-octane, n-nonane, cyclohexane, methylcyclohexane, toluene, xylene, ethylbenzene, ethyl acetate, butyl acetate, isobutyl acetate, sec-butyl acetate, diisopropyl ether, dimethyl carbonate, isopropyl acetate, methyl isobutyl ketone, methyl ethyl ketone, acetone, chloroform, diethyl carbonate, benzyl alcohol, butanol, propanol, pentanol, methanol, ethanol, and / or isopropanol.

[0126] Figure 2 This is a schematic process flow diagram illustrating a method for manufacturing a porous polymer membrane according to another embodiment of the present invention.

[0127] In one embodiment, the manufacturing method may further include irradiating a second primary porous membrane discharged from the liquid processing chamber with an electron beam (step S20B).

[0128] Crosslinking reactions can be carried out by irradiating the 2B primary porous membrane, in which at least 80% of the oxygen in the pores is replaced by the non-reactive liquid, with an electron beam. This prevents the consumption of oxygen-induced free radicals and inhibits or reduces the formation of byproducts.

[0129] Figure 5 This is a schematic process diagram illustrating, for example, the passage of the first B primary porous membrane through the liquid processing chamber in a method for manufacturing a porous polymer membrane according to one embodiment of the present invention.

[0130] In one embodiment, the second primary porous membrane can be irradiated with an electron beam within 60 seconds of the discharge of the second primary porous membrane from the liquid processing chamber. Therefore, the crosslinking reaction can occur in a state where the non-reactive liquid within the pores of the second primary porous membrane has not been substantially replaced by oxygen again, or the replacement amount is minimal, thereby simultaneously improving the chemical resistance and heat resistance of the manufactured porous polymer membrane.

[0131] In one embodiment, the primary porous membrane irradiated with an electron beam may be performed within 50 seconds, 40 seconds, or 30 seconds after the primary porous membrane begins to drain from the liquid processing chamber.

[0132] In one embodiment, electron beam irradiation of the second B primary porous membrane can be performed in an inert gas atmosphere chamber. For example, the inert gas atmosphere chamber may include an electron beam irradiation unit. Regarding the electron beam irradiation unit, please refer to the above description.

[0133] Figure 6 This is a schematic process diagram illustrating, for example, the passage of the first B primary porous membrane through the liquid processing chamber and the inert gas atmosphere chamber in a method for manufacturing a porous polymer membrane according to one embodiment of the present invention. Figure 6 In China, the inert gas atmosphere chamber is simply referred to as the "inert atmosphere chamber".

[0134] The electron beam irradiation device can be installed inside or outside the inert gas atmosphere chamber. For example, when the electron beam irradiation device is installed outside the inert gas atmosphere chamber, the electron beam can be used to irradiate the second primary porous membrane traveling inside the inert gas atmosphere chamber through the electron beam penetration window.

[0135] For example, the front end of the inert gas atmosphere chamber may include a membrane travel section, and the rear end of the chamber may include an electron beam irradiation section. For example, the travel time of the second B primary porous membrane from discharge from the liquid processing chamber until it is irradiated by the electron beam through the electron beam irradiation section in the inert gas atmosphere chamber may be less than 60 seconds.

[0136] As a non-limiting example, the inert gas atmosphere chamber can refer to a device filled with inert gas to maintain the internal space in an inert gas state, such as being connected to a gas inlet, outlet, gas flow control valve, etc.

[0137] For example, the inert gas may include N2, He, Ar, Ne, etc.

[0138] In one embodiment, the liquid processing chamber and the inert gas atmosphere chamber can be arranged consecutively.

[0139] As a non-limiting example, the liquid processing chamber and the inert gas atmosphere chamber can be connected by connecting components such as pipes or conduits, or the outlet of the liquid processing chamber and the inlet of the inert gas atmosphere chamber can be directly contacted and connected. For example, the first B primary porous membrane can be continuously added to the inert gas atmosphere chamber after passing through the liquid processing chamber.

[0140] In one embodiment, before irradiating the second B primary porous membrane with an electron beam, the process may further include a step of refilling the second B primary porous membrane into the liquid processing chamber more than once. Therefore, the amount of oxygen removed from the pores of the second B primary porous membrane can be easily controlled.

[0141] In one embodiment, the winding roller may be disposed outside or inside the inert gas atmosphere chamber.

[0142] In one embodiment, the winding roller may be disposed outside the inert gas atmosphere chamber, and the electron beam may be used to irradiate the first B primary porous membrane traveling within the inert gas atmosphere chamber with an electron beam irradiation unit.

[0143] The irradiation direction of the electron beam can be, for example, substantially perpendicular to one side of the second B primary porous membrane. In this case, the electron beam irradiation device can be controlled by taking into account factors such as the energy density and accelerating voltage of the electron beam, the diameter of the winding roller, the thickness of the primary porous polymer membrane, and the energy required for crosslinking.

[0144] In the inert gas atmosphere chamber, a porous polymer film cross-linked by electron beam irradiation can be discharged from the inert gas atmosphere chamber, conveyed to the winding roller, and wound up. The porous polymer film discharged from the inert gas atmosphere chamber can be conveyed to the winding roller and wound up under atmospheric atmosphere or an additional vacuum atmosphere. As a non-limiting example, the additional vacuum atmosphere can be an additional vacuum atmosphere chamber, etc.

[0145] In one embodiment, the second primary porous membrane can be wound in the electron beam irradiation section, and the wound second primary porous membrane can be irradiated with an electron beam.

[0146] In one embodiment, the winding roller may be disposed inside the inert gas atmosphere chamber, and the electron beam irradiation unit may irradiate the second primary porous membrane wound by the winding roller inside the inert gas atmosphere chamber with an electron beam.

[0147] For information regarding electron beam irradiation, please refer to the above content.

[0148] Regarding the first B primary porous membrane and the second B primary porous membrane, refer to the above description of the first A primary porous membrane. For example, the difference between the first B primary porous membrane and the second B primary porous membrane lies only in whether at least a portion of the oxygen in the pores is replaced by the non-reactive liquid or the non-reactive liquid and / or the inert gas; the types of replacement can be the same. For example, the membrane introduced into the liquid processing chamber can be called the first B primary porous membrane, which refers to a membrane in which the oxygen in the pores is not replaced by the non-reactive liquid. For example, the membrane discharged from the liquid processing chamber can be called the second B primary porous membrane, which can refer to a membrane in which at least a portion of the oxygen in the pores is replaced by the non-reactive liquid. Furthermore, for example, when the first B primary porous membranes both pass through the liquid processing chamber and the inert gas atmosphere chamber, the membrane discharged from the inert gas atmosphere chamber can be referred to as the second B primary porous membrane, which can refer to a membrane in which at least a portion of the oxygen in the pores is replaced by the non-reactive liquid and / or the inert gas.

[0149] In one embodiment, the oxygen replacement rate of the second primary porous membrane when it is discharged from the liquid processing chamber can be 80% or more, 90% or more, or 95% or more.

[0150] The oxygen replacement rate can be a percentage value calculated as the ratio of the total number of moles of oxygen removed from the membrane in the liquid treatment chamber to the total number of moles of oxygen in the pores of the first B primary porous membrane before it was added to the liquid treatment chamber.

[0151] There is no particular upper limit to the oxygen replacement rate; the higher the value, the more it can prevent or reduce side reactions caused by oxygen.

[0152] As a non-limiting example, before the first B primary porous membrane is added to the liquid processing chamber, the total number of moles of oxygen present in the pores can be referenced to "the total number of moles of oxygen present in the pores (n)". I The above content can be used to calculate, for example, the total volume (V) of the first B primary porous membrane.F Multiply by porosity (R) P To calculate pore volume (V) P ), and the pore volume (V P Substitute the values ​​into the ideal gas law to calculate.

[0153] As a non-limiting example, the total number of moles of oxygen removed from the first B primary porous membrane in the liquid processing chamber can be referenced to "the total number of moles of oxygen removed from the pores (n)". F The calculation can be performed based on the above content, for example, an oxygen analyzer can be installed in the liquid processing chamber to measure the increase in oxygen partial pressure (P). O ), and increase the partial pressure of oxygen (P) O Substitute the values ​​into the ideal gas law to calculate.

[0154] For information regarding the oxygen analyzer, please refer to the above content.

[0155] In one embodiment, the first primary porous membrane 1B and the second primary porous membrane 2B can be transported in a roll-to-roll manner. Figure 5 This is a schematic process block diagram illustrating a method for manufacturing a porous polymer membrane according to another embodiment of the present invention.

[0156] For information regarding the roll-to-roll method, please refer to the above content.

[0157] A method for manufacturing a porous polymer membrane according to another embodiment of the present invention may include: preparing an inert gas atmosphere chamber comprising an intake roller at a front end and an electron beam irradiation section at a rear end (step S10C); and adding a first primary porous membrane (step S20C) to the inert gas atmosphere chamber, wherein the first primary porous membrane can satisfy the intake index I defined by the following formula 3. S It travels on the suction roller under conditions of 1 or higher.

[0158] [Formula 3] I S =(S1×S2) / 100 In Equation 3, S1 represents the suction pressure (mmAq) of the suction roller, and S2 represents the time (seconds) required for the first C primary porous membrane to travel on the suction roller. The first C primary porous membrane can travel along the suction roller disposed at the front end of the inert gas atmosphere chamber, and S2 can refer to the time (seconds) required for the first C primary porous membrane to travel along the suction roller, for example, it can be substantially the same as the time (seconds) for which the suction pressure is applied to the first C primary porous membrane.

[0159] Therefore, oxygen present inside the pores of the first C primary porous membrane can be effectively removed, thereby effectively preventing or inhibiting side reactions caused by oxygen in the subsequent crosslinking process.

[0160] In some implementation schemes, I S The values ​​can be 1 to 1000, 1 to 900, 1 to 700, 1 to 500, 1 to 300, 1 to 250, 1 to 200, 1 to 150, or 1 to 100. Therefore, oxygen present in the pores within the primary porous membrane of the first C can be removed more effectively.

[0161] In one embodiment, S1 in Formula 3 can be less than 5000 mmAq (less than 49033.25 Pa), for example, it can be 100 mmAq to 5000 mmAq (980.65 Pa to 49033.25 Pa), 300 mmAq to 5000 mmAq (2941.99 Pa to 49033.25 Pa), 500 mmAq to 5000 mmAq (2941.99 Pa to 49033.25 Pa), or 1000 mmAq to 5000 mmAq. Therefore, deformation of the primary porous membrane (C1) can be prevented, and oxygen present in its pores can be effectively removed.

[0162] In one embodiment, S2 in Formula 3 can be 0.1 seconds to 20 seconds, 0.1 seconds to 15 seconds, 0.1 seconds to 5 seconds, or 0.1 seconds to 2 seconds. Therefore, the overall efficiency of the manufacturing method can be improved, and oxygen present in the pores of the first C primary porous membrane can be sufficiently removed.

[0163] Figure 3 This is a schematic process flow diagram illustrating a method for manufacturing a porous polymer membrane according to another embodiment of the present invention.

[0164] In one embodiment, the manufacturing method may further include irradiating the first C primary porous film with an electron beam in the electron beam irradiation section (step S30C).

[0165] Crosslinking reactions can be carried out by irradiating a primary porous membrane (C1) with an electron beam to which at least 80% of the oxygen in the pores is replaced by an inert gas. This can prevent the consumption of free radicals caused by oxygen and inhibit or reduce the formation of byproducts.

[0166] Regarding the inert gas, please refer to the above content.

[0167] Regarding the first C primary porous membrane, refer to the above description of the first A primary porous membrane.

[0168] In one embodiment, the oxygen replacement rate of the first primary porous membrane when it is discharged from the inert gas atmosphere chamber can be 80% or more, 90% or more, or 95% or more.

[0169] The oxygen replacement rate can be expressed as a percentage, which is the ratio of the total number of moles of oxygen removed from the primary porous membrane when it passes through the suction roller to the total number of moles of oxygen present in the pores of the primary porous membrane before it is added to the inert gas atmosphere chamber.

[0170] When the primary porous membrane of type 1C passes through the suction roller, the total number of moles of oxygen removed from the primary porous membrane of type 1C can be substantially the same as the total number of moles of oxygen removed from the pores of the primary porous membrane of type 1C when the electron beam is irradiated by the electron beam irradiation unit.

[0171] Furthermore, the total number of moles of oxygen removed from the primary porous membrane in the inert gas atmosphere chamber can be substantially the same as the total number of moles of oxygen removed from the membrane when passing through the suction roller.

[0172] There is no particular upper limit to the oxygen replacement rate; the higher the value, the more it can prevent or reduce side reactions caused by oxygen.

[0173] As a non-limiting example, the total number of moles of oxygen present in the pores of the first C primary porous membrane before it is added to the inert gas atmosphere chamber can be referenced to "the total number of moles of oxygen present in the pores (n)". I The above content of ")" can be calculated, for example, the total volume (V) of the first C primary porous membrane can be calculated. F Multiply by porosity (R) P To calculate pore volume (V) P ), and the pore volume (V P Substitute the values ​​into the ideal gas law to calculate.

[0174] As a non-limiting example, the total number of moles of oxygen removed from the first C primary porous membrane can be referenced to "the total number of moles of oxygen removed from the pores (n)". F The calculation can be performed based on the above content, for example, by installing an oxygen analyzer in the inert gas atmosphere chamber to measure the increase in oxygen partial pressure (P). O ), and increase the partial pressure of oxygen (P) O Substitute the values ​​into the ideal gas law to calculate.

[0175] For information regarding the oxygen analyzer, please refer to the above content.

[0176] In one embodiment, the first C primary porous membrane can be transported in a roll-to-roll manner.

[0177] Figure 7 This is a schematic process diagram illustrating, for example, the passage of the first primary porous membrane (IC) through the inert gas atmosphere chamber in a method for manufacturing a porous polymer membrane according to one embodiment of the present invention.

[0178] For example, the front end of the inert gas atmosphere chamber may include a suction travel section containing a suction roller, and the rear end may include an electron beam irradiation section. For example, the suction travel section and the electron beam irradiation section can be continuously connected via a roll-to-roll process, allowing the entire process to proceed continuously. For details regarding the roll-to-roll method and the electron beam irradiation section, please refer to the above description.

[0179] In one embodiment, the primary porous membrane can be irradiated with an electron beam within 60 seconds of passing through the suction roller. Therefore, the crosslinking reaction can occur in regions of the primary porous membrane where oxygen has been removed or where the introduced inert gas is substantially not replaced by oxygen again, or in very small amounts, thereby simultaneously improving the chemical and heat resistance of the manufactured porous polymer membrane.

[0180] In one embodiment, the primary porous membrane can be irradiated with an electron beam within 50 seconds, 40 seconds, or 30 seconds after it begins to pass through the suction roller.

[0181] As a non-limiting example, the electron beam irradiation section may include an electron beam irradiation device, and there is no particular limitation on the type of electron beam irradiation device.

[0182] The electron beam irradiation device can be installed inside or outside the inert gas atmosphere chamber. For example, when the electron beam irradiation device is installed outside the inert gas atmosphere chamber, the electron beam can be used to irradiate the first C primary porous membrane traveling inside the inert gas atmosphere chamber through the electron beam penetration window.

[0183] In one embodiment, the first primary porous membrane can be provided in a wound state and conveyed to the inert gas atmosphere chamber by unwinding.

[0184] In one embodiment, the conveyed primary porous membrane 1C can be wound back into a roll.

[0185] In one embodiment, the winding roller may be disposed outside or inside the inert gas atmosphere chamber.

[0186] In one embodiment, the winding roller may be disposed outside the inert gas atmosphere chamber, and the electron beam may be used to irradiate the first C primary porous membrane traveling within the inert gas atmosphere chamber with an electron beam irradiation unit.

[0187] The irradiation direction of the electron beam can, for example, be substantially perpendicular to one side of the first C primary porous membrane. In this case, the electron beam irradiation device can be controlled by taking into account factors such as the energy density and accelerating voltage of the electron beam, the diameter of the winding roller, the thickness of the primary porous polymer membrane, and the energy required for crosslinking.

[0188] In the inert gas atmosphere chamber, a porous polymer membrane manufactured by crosslinking through electron beam irradiation can be discharged from the inert gas atmosphere chamber, conveyed to the winding roller, and wound up. The porous polymer membrane discharged from the inert gas atmosphere chamber can be conveyed to the winding roller and wound up under atmospheric atmosphere or an additional inert gas atmosphere. As a non-limiting example, the additional inert gas atmosphere can be an additional inert gas atmosphere chamber, etc.

[0189] In one embodiment, the first C primary porous membrane can be wound in the electron beam irradiation section, and the wound first C primary porous membrane can be irradiated with an electron beam.

[0190] In one embodiment, the winding roller may be disposed inside the inert gas atmosphere chamber, and the electron beam irradiation unit may irradiate the first C primary porous film wound by the winding roller within the inert gas atmosphere chamber with an electron beam. For details regarding the electron beam irradiation, please refer to the above description.

[0191] Steps S10A, S20A, S30A, S10B, S20B, S10C and / or S20C can be performed at room temperature.

[0192] In one embodiment, the method for manufacturing the porous polymer membrane can be provided as a method for manufacturing a porous polymer membrane for a secondary battery.

[0193] Porous polymer membranes manufactured by the manufacturing method according to an embodiment of the present invention can have a crosslinking reactivity greater than 1.5 as defined by Formula 4 below.

[0194] [Formula 4] Crosslinking reactivity degree = (A×B / 10000) - C In Equation 4, A is the temperature at which the porous polymer membrane breaks when heated to 220°C at a heating rate of 5°C / min using thermomechanical analysis (TMA), i.e., the melt fracture temperature (°C); B is the percentage of the mass of undissolved residual solids divided by the initial mass after the porous polymer membrane has been immersed in xylene at 135°C for 3 hours, i.e., the gel content; and C is the high load melt index (HLMI) of the porous polymer membrane measured according to ASTM D1238 standard at a temperature of 190°C and a load of 21.6 kg.

[0195] In one embodiment, the degree of crosslinking reactivity can be less than 3.

[0196] The porous polymer membrane can have improved solvent resistance. Therefore, even when in contact with organic solvents, damage to the porous polymer membrane can be suppressed or reduced.

[0197] The porous polymer membrane can possess improved heat resistance. Therefore, even at high temperatures, it can suppress damage caused by external forces, and achieve long-term operational stability and reliability even after repeated exposure to high temperatures.

[0198] The thermomechanical analysis can be performed, for example, using a thermomechanical analysis apparatus. The porous polymer membrane can be fixed at both ends in the apparatus, and then the temperature is increased while it is being stretched. For example, with both ends of the porous polymer membrane fixed, a force of 0.015 N is applied, and the temperature is increased from 25°C to 220°C at a rate of 5°C / min. During the temperature increase while the tensile force is applied, the temperature at which the porous polymer membrane fractures can be used as the melt fracture temperature.

[0199] For example, the thermomechanical analysis apparatus may be the TMA450 model from TA Instruments, but is not limited to this.

[0200] For example, the higher the durability of the porous polymer membrane at high temperatures, the higher its melt fracture temperature can be.

[0201] In one implementation, A in Formula 4 can be above 175°C.

[0202] In one embodiment, A in Formula 4 can be 175°C to 250°C or 160°C to 200°C.

[0203] For example, B in Formula 4 can refer to the percentage of the mass of the undissolved residual solids after immersing a sample (e.g., 3g) of the porous polymer membrane in xylene at 135°C for 3 hours, divided by the initial mass before immersion.

[0204] For example, 200 ml of xylene can be heated to 135°C, and then 3 g of the porous polymer membrane can be added to the xylene. Three hours after addition, the solids are filtered and dried, and then weighed. The mass of the residual solids is converted to a percentage by the ratio of the mass of the initial addition of 3 g, thus allowing the calculation of B.

[0205] For example, the higher the solvent resistance of the porous polymer membrane to organic solvents, the higher its gel content can be.

[0206] In one implementation, B in Equation 4 can be 90% or more.

[0207] In one implementation, B in Formula 4 can be 90% or more, or 95% or more. For example, B can be 95% to 100%.

[0208] Within the aforementioned range, the solvent resistance of the porous polymer membrane to organic solvents can be further improved.

[0209] In one embodiment, the solubility of the porous polymer membrane in xylene can refer to the ratio of the dissolved portion to the total added amount, which can be defined as the value of 100 minus the gel content, and can be calculated using the formula: solubility = 100 - B (%). For example, the solubility of the porous polymer membrane in xylene can be less than 20%, less than 15%, less than 10%, or less than 5%.

[0210] For example, C in Formula 4 refers to High Load Melt Flow Index (HLMI). For example, C can refer to the mass (g / 10min) of molten polymer extruded under a load of 21.6 kg for 10 minutes after the porous polymer membrane is cut into a sample, and then extruded at 190°C for 10 minutes.

[0211] Furthermore, for example, C is defined as the high load melt index (HLMI) of a porous polymer membrane, measured in g / 10 minutes, after 3 g of the membrane is placed in a perforated chamber at a temperature of 190°C and discharged under a load of 21.6 kg for ten minutes. For example, the diameter and length of the pores can be formed to be the same as those of a standard orifice: 2.095 ± 0.005 mm and 8.000 ± 0.025 mm.

[0212] In addition, for example, C can be measured according to ASTM D1238.

[0213] For example, the higher the processability of the porous polymer membrane, the higher the HLMI can be.

[0214] In one embodiment, C in Formula 4 may be less than 0.05 g / 10 minutes. In some embodiments, C in Formula 4 may be less than 0.03 g / 10 minutes or less than 0.02 g / 10 minutes.

[0215] Within the aforementioned range, the processability of the porous polymer membrane can be further improved.

[0216] When the crosslinking reaction of the porous polymer membrane is too low, it may reduce the processability, solvent resistance and / or high temperature durability of the porous polymer membrane.

[0217] In one embodiment, the porous polymer membrane may have a crosslinking degree greater than 1.5 to 3 or 2 to 3.

[0218] In one embodiment, the porous polymer membrane can have a puncture strength of 0.15 N / μm or higher. Therefore, the porous polymer membrane can have improved mechanical properties.

[0219] The porous polymer membrane according to embodiments of the present invention can be applied to a variety of electrochemical elements, including separators for secondary batteries, and can be provided, for example, as a membrane for separators.

[0220] The separator for secondary batteries according to embodiments of the present invention may include the above-mentioned porous polymer membrane.

[0221] The separator for the secondary battery may further include, for example, a coating containing a gas adsorbent.

[0222] The gas adsorbent may, for example, comprise zeolite, and may further comprise one or more porous inorganic particles selected from aluminum hydroxide (Al(OH)3), magnesium hydroxide (Mg(OH)2), aluminum oxide (Al2O3), magnesium oxide (MgO), calcium oxide (CaO), barium sulfate (BaSO4), boehmite, titanium dioxide (TiO2), silicon dioxide (SiO2), and clay. As a non-limiting example, the average size (particle size, D) of the gas adsorbent... 50 The size can range from 0.01 to 5 μm.

[0223] The coating may further comprise a material selected from polyvinylidene fluoride-co-hexafluoropropylene, polyvinylidene fluoride-co-trichloroethylene, polymethyl methacrylate, polyacrylonitrile, polyvinylpyrrolidone, polyvinyl acetate, ethylene-vinyl acetate copolymer, polyimide, polyethylene oxide, cellulose acetate, cellulose acetate butyrate, and cellulose acetate propionate. At least one binder selected from propionate, cyanoethyl pullullan, cyanoethyl polyvinyl alcohol, cyanoethyl cellulose, cyanoethyl sucrose, pullullan, carboxyl methyl cellulose, and polyvinyl alcohol.

[0224] In some embodiments, the thickness of the separator for the secondary battery can be from 10 μm to 250 μm.

[0225] The separation membrane for gas separation according to an embodiment of the present invention may include the above-described porous polymer membrane.

[0226] The gas separation membrane may further include a selective layer. The selective layer may contain, but is not limited to, graphene oxide, metal-organic frameworks (MOFs), hydrotalcite, zirconate, calcium oxide, etc. The gas separation membrane may further include an intermediate layer containing siloxane-based polymers and / or polyacetylene-based polymers between the porous polymer membrane and the selective layer; this intermediate layer can act as an adhesive layer. The above-described gas separation membrane can selectively separate gases such as carbon dioxide, hydrogen, helium, nitrogen, oxygen, and olefins.

[0227] <Manufacturing System for Porous Polymer Membranes> According to one embodiment of the present invention, a method for manufacturing a porous polymer membrane may irradiate each of the primary porous membranes (e.g., the first A primary porous membrane, the second B primary porous membrane, and / or the first C primary porous membrane) with an electron beam during the winding process.

[0228] The electron beam irradiation section may refer to, for example, the curing section or the cross-linking section.

[0229] The method for manufacturing the porous polymer membrane can be performed, for example, using a porous polymer membrane manufacturing apparatus, the apparatus comprising: at least one conveying roller for conveying a primary porous membrane; a winding machine including a winding roller for winding the primary porous membrane; and an electron beam irradiation device including an electron beam irradiation section, wherein the electron beam irradiation device is configured to be spaced less than 100 cm from the central axis of the winding roller, and the electron beam irradiation section is disposed toward the central axis of the winding roller.

[0230] According to the manufacturing system for the porous polymer membrane, cross-linking can be achieved during the winding process by electron beam irradiation, thereby enabling high-speed and mass production of porous polymer membranes at a lower cost.

[0231] Figure 8 This is a schematic diagram of a manufacturing system for a porous polymer membrane according to an exemplary embodiment.

[0232] In the traveling section P2, the primary porous membrane can be moved, for example, in a linear or Z-shaped pattern. When the primary porous membrane is moved linearly in the traveling section P2 while being irradiated with an electron beam without being irradiated during the winding process in the electron beam irradiation section, the electron beam irradiation time needs to be ensured, thus reducing production speed and requiring multiple electron beam irradiation devices, potentially significantly increasing investment costs. When the primary porous membrane is moved in a Z-shaped pattern in the traveling section P2 while being irradiated without being irradiated during the winding process in the electron beam irradiation section, multiple electron beam irradiation devices are required, and electron beam irradiation requires a wider area, thus potentially significantly increasing investment costs. Furthermore, to achieve uniform electron beam irradiation, medium-energy or higher electron beam irradiation may be necessary.

[0233] According to one embodiment of the present invention, a manufacturing system for porous polymer membranes can irradiate each of the primary porous membranes (e.g., the first A primary porous membrane, the second B primary porous membrane, and / or the first C primary porous membrane) with an electron beam during the winding process, thereby eliminating the need for multiple electron beam irradiation devices, allowing the use of low-energy electron beam irradiation, eliminating the need for a wide area of ​​electron beam irradiation, and increasing production speed.

[0234] In one embodiment, the manufacturing system may further include a load section P1 for unwinding a primary porous membrane wound in a roll and providing it to a travel section P2.

[0235] In one embodiment, in the electron beam irradiation unit P3, the winding can be performed by a winding machine including a winding roller, and the electron beam irradiation of the wound primary porous membrane can be performed in the direction of the central axis of the winding roller.

[0236] Reference Figure 8 The manufacturing system may include: a dewinding machine including a dewinding roller 100, a winding machine including a winding roller 200, and an electron beam irradiation device 300.

[0237] For example, the unwinder and the winding machine may further include a running part such as a motor for operating each roller, and a frame part for supporting each component.

[0238] The primary porous membrane 10 can be provided by the unwinding roller 100. The primary porous membrane 10 can be provided to the system in a state of being wound on the unwinding roller 100, which rotates and unfolds the primary porous membrane 10, thereby providing it to the winding roller 200.

[0239] In one embodiment, the speed of unwinding and winding can be referred to the above-described manufacturing method. The rotational speed can be adjusted taking into account factors such as production scale, diameter of the unwinding roller 100, thickness of the primary porous membrane 10, and energy required for curing.

[0240] As a non-limiting example, the diameter of the rolled primary porous membrane wound on the unwinding roller 100 can be, for example, from 10 cm to 30 cm. The diameter can refer to the cross-sectional diameter of the roll of the primary porous membrane, or it can refer to the cross-sectional diameter before unwinding. The diameter of the unwinding roller 100 can be adjusted considering factors such as production scale, the thickness of the primary porous membrane 10, the energy required for curing, and the available space in the system.

[0241] The unwinding roller 100 can be disposed in the load section P1. The load section P1 can be the raw material supply area of ​​the system, and can be in a vacuum atmosphere (At). vac，1 The "vacuum atmosphere" mentioned includes not only a complete vacuum state, but may also include 10 -1 The following is a vacuum-like state.

[0242] In one embodiment, the manufacturing system may further include a supply section that forms a primary porous membrane by extruding and stretching a polymer-containing raw material, and then winds the primary porous membrane into a roll and provides it to the loading section.

[0243] Regarding the primary porous membrane 10, please refer to the above content in the manufacturing method.

[0244] The primary porous membrane 10 provided from the unwinding roller 100 can be conveyed to the winding roller 200 via at least one conveying roller (401 to 407). Figure 8 The diagram shows seven conveyor rollers, but the number of conveyor rollers is not limited to this and can be adjusted considering factors such as the system's installation space, the pore diameter of the primary porous membrane 10, and the type of resin. For example, there can be one to 20 conveyor rollers.

[0245] The travel distance of the primary porous membrane 10 before the winding roller 200 can be adjusted by the number and setting position of the conveying rollers (401 to 407).

[0246] like Figure 8 As shown, between the unwinding roller 100 and the winding roller 200, a conveying roller (401 to 407) can be arranged in a zigzag pattern, so that the primary porous membrane 10 can be conveyed to the winding roller 200 without damage.

[0247] Some of the conveying rollers (402 to 405) may be provided in the traveling section P2. The traveling section P2 may be provided, for example, between the unwinding roller 100 and the winding roller 200, and may be the area through which the primary porous membrane 10 passes during its movement from the unwinding roller 100 to the winding roller 200.

[0248] The traveling section P2 can be in a vacuum atmosphere (At) vac，2 Vacuum atmosphere in the traveling section P2 (At) vac，2 It can be in contact with the vacuum atmosphere (At) of the load section P1. vac，1 (Same or different)

[0249] In one embodiment, the pressure of the traveling section P2 may be lower than the pressure of the load section P1.

[0250] For example, the vacuum atmosphere (At) of the load section P1 vac，1 ) can be 10 -1 The following is a vacuum-like state.

[0251] The vacuum level of the traveling section P2 can be referenced, for example, the above-described vacuum atmosphere chamber.

[0252] The primary porous membrane 10 can be wound onto the winding roller 200 via the traveling section P2. For example, the primary porous membrane 10 can be wound up while the winding roller 200 is rotating.

[0253] The diameter of the spiral porous polymer membrane wound on the winding roller 200 can be referenced above. The diameter of the winding roller 200 can be adjusted by taking into account factors such as production scale, the thickness of the primary porous membrane 10, the energy required for curing, and the available space in the system.

[0254] The winding roller 200 can be provided in the electron beam irradiation section P3. In the electron beam irradiation section P3, the primary porous membrane 10 can be cross-linked or cured by electron beam irradiation. An electron beam irradiation device 300 can be provided in the electron beam irradiation section P3, which can irradiate the primary porous membrane 10 wound onto the winding roller 200 with an electron beam.

[0255] The electron beam irradiation device 300 can irradiate an electron beam toward the central axis of the winding roller 200. Therefore, the primary porous membrane 10 continuously wound onto the winding roller 200 can be cross-linked or cured by the electron beam. By rotating the winding roller 200, the primary porous membrane 10 can be repeatedly exposed to the electron beam, so even if a low-energy electron beam is irradiated, the primary porous membrane 10 can be fully cross-linked or cured.

[0256] like Figure 8As shown, the electron beam irradiation device 300 can be positioned above the winding roller 200, but is not limited thereto. According to another embodiment, the electron beam irradiation device 300 can be positioned below the winding roller 200, irradiating the upper part with an electron beam.

[0257] Regarding the electron beam irradiation device 300, please refer to the above content in the manufacturing method.

[0258] The primary porous membrane 10, which is in contact with the surface of the winding roller 200, can pass through the electron beam irradiation area (A) multiple times as the winding roller 200 rotates. rad Each time a low-energy electron beam passes through the electron beam irradiation area (A) rad When the primary porous membrane 10 is partially cross-linked or cured, the degree of cross-linking or curing of the primary porous membrane 10 can be increased as the number of rotations of the winding roller 200 increases.

[0259] As the winding roller 200 rotates, the primary porous membrane 10 can be continuously wound up, increasing the total thickness of the primary porous membrane 10 wound in multiple layers on the surface of the winding roller 200. Therefore, the distance between any region of the primary porous membrane 10 in contact with the surface of the winding roller 200 and the electron beam irradiation device 300 gradually increases, while the amount of electron beam reaching the membrane may decrease or disappear. Thus, the primary porous membrane 10 can be irradiated with an electron beam to achieve an appropriate level of accumulation.

[0260] For example, any region of the primary porous membrane 10 can be irradiated by the electron beam irradiation region (A) of the electron beam irradiation device 300. rad The number of passes can be adjusted from 100 to 300. The number of passes can be adjusted taking into account the energy density and accelerating voltage of the electron beam, the diameter of the winding roller 200, the distance between the electron beam irradiation device 300 and the central axis of the winding roller 200, the thickness of the primary porous membrane 10, and the energy required for curing.

[0261] Electron beam irradiation section P3 can be purged with nitrogen gas, for example. N2 Cooling is performed. Therefore, it can prevent temperature rise caused by heat generated by electron beam irradiation and the resulting polymer denaturation.

[0262] The unwinding roller 100 and the winding roller 200 can rotate together. For example, in the initial stage of supplying the primary porous membrane 10, the primary porous membrane 10 can be fed to the winding roller 200 by the conveying rollers (401 to 407) while only the unwinding roller 100 is rotated. When the primary porous membrane 10 begins to be wound onto the winding roller 200, the unwinding roller 100 and the winding roller 200 can rotate at the same speed. Furthermore, in the later stage, when all the primary porous membrane 10 wound on the unwinding roller 100 has been supplied, only the winding roller 200 can be rotated.

[0263] In one embodiment, the winding roller 200 may continue to rotate while the electron beam is being irradiated after the primary porous membrane 10 has been completely wound onto the winding roller 200. An additional amount of rotation of the winding roller 200 can be determined to ensure adequate curing of the final wound primary porous membrane 10.

[0264] For example, the porosity of the porous polymer membrane 20 manufactured by the manufacturing system can be from 10% to 80%. Through the crosslinking or curing process, bonds can be formed between the polymer chains of the primary porous membrane 10, so the porosity of the porous polymer membrane 20 can be lower than that of the primary porous membrane 10.

[0265] For example, the porous polymer membrane 20 manufactured by the manufacturing system can have a pore diameter of less than 200 nm. Through the crosslinking or curing process, bonds can be formed between the polymer chains of the primary porous membrane 10; therefore, the pore diameter of the porous polymer membrane 20 can be smaller than the pore diameter of the primary porous membrane 10.

[0266] <Equipment for manufacturing porous polymer membranes> According to one embodiment of the invention, a method for manufacturing a porous polymer membrane may irradiate each of the primary porous membranes (e.g., the first A primary porous membrane, the second B primary porous membrane, and / or the first C primary porous membrane) with an electron beam during the winding process.

[0267] The method for manufacturing the porous polymer membrane can be performed, for example, using a porous polymer membrane manufacturing apparatus, the apparatus comprising: at least one conveying roller for moving a primary porous membrane; a winding machine including a winding roller for winding the primary porous membrane; and an electron beam irradiation device including an electron beam irradiation section, wherein the electron beam irradiation device is positioned less than 100 cm away from the central axis of the winding roller, and the electron beam irradiation section is disposed toward the central axis of the winding roller.

[0268] According to the manufacturing equipment for the porous polymer membrane, cross-linking by electron beam irradiation can be carried out during the winding process, thereby providing high-speed and mass production of porous polymer membranes at a reduced cost.

[0269] In one embodiment, the manufacturing apparatus may further include a unwinder comprising unwinding rollers for unwinding a primary porous polymer film wound in a roll, the conveying rollers being able to move the primary porous polymer film from the unwinder to the winding machine.

[0270] In one embodiment, the manufacturing apparatus may further include a vacuum atmosphere chamber at the rear end of the chamber, comprising the electron beam irradiation unit. The electron beam irradiation device may be installed inside or outside the vacuum atmosphere chamber.

[0271] In one embodiment, the winding roller may be installed inside the vacuum atmosphere chamber.

[0272] Regarding the vacuum atmosphere chamber, please refer to the above content in the manufacturing method.

[0273] In one embodiment, the manufacturing apparatus may further include a liquid handling chamber.

[0274] In one embodiment, the manufacturing apparatus may further include a liquid handling chamber and an inert gas atmosphere chamber.

[0275] In one embodiment, the winding roller may be mounted outside the liquid processing chamber.

[0276] In one embodiment, the winding roller may be installed inside the inert gas atmosphere chamber located downstream of the liquid processing chamber.

[0277] Regarding the liquid handling chamber and the inert gas atmosphere chamber, please refer to the above content in the manufacturing method.

[0278] In one embodiment, the manufacturing apparatus may further include an inert gas atmosphere chamber comprising an intake roller at the front end of the chamber and an electron beam irradiation section at the rear end of the chamber.

[0279] In one embodiment, the winding roller may be installed inside the inert gas atmosphere chamber that includes the suction roller and the electron beam irradiation section.

[0280] Regarding the inert gas atmosphere chamber including the suction roller and the electron beam irradiation section, please refer to the above content in the manufacturing method.

[0281] As a non-limiting example, the aforementioned chamber can be formed of materials such as metal, alloy, or plastic.

[0282] In one embodiment, the manufacturing apparatus may further include extrusion and stretching devices that form a primary porous membrane by extruding and stretching a polymer-containing raw material. The raw material may be, for example, polymer particles, a melt containing polymer and / or oil, etc., and reference can be made to the above description of the manufacturing method regarding the polymer.

[0283] As a non-limiting example, the extrusion and stretching apparatus may include dies such as T-die heads, and may include single-axis or biaxial stretching devices such as tenter frame equipment.

[0284] In one embodiment, the apparatus for manufacturing the porous polymer membrane may, as needed, further include known components required for manufacturing the membrane via a roll-to-roll process, without particular limitation.

[0285] The manufacturing equipment may further include, for example, a gas flow controller (mass flow controller, MFC), a pressure controller, a vacuum pump, a pressure sensor, a purging device, a cooling device, a gas filter, and multiple nozzles.

[0286] The aforementioned porous polymer membrane 20 can be applied in multiple fields. For example, it can be used in the electronics / electrical field for secondary battery separators and purification of chemicals required for semiconductor processes; in the biological field for hemodialysis (acting as an artificial kidney), fused membranes for artificial lungs, plasma purification membranes, and breathable medical clothing; in the water treatment field for the isolation of pathogenic bacteria in wastewater treatment plants and seawater desalination; in the petrochemical field for the purification of chemicals or organic solvents produced in petrochemical processes and for the separation of gases such as CO2 membranes.

[0287] The embodiments of the present invention will be further described below with reference to specific experimental examples. The embodiments and comparative examples included in the experimental examples are for illustrative purposes only and are not intended to limit the scope of the claims.

[0288] Example Examples 1 to 3, and Comparative Examples 1 and 2 In Examples 1 to 3 and Comparative Examples 1 and 2, porous polymer membranes were manufactured by the same method as described below, except that the vacuum level in the vacuum chamber and the travel time of the membrane before electron beam irradiation in the vacuum chamber were changed as shown in Table 2 below.

[0289] At room temperature, a primary porous polyethylene (PE) membrane (porosity: approximately 45%) with a thickness of 10 μm is added to a vacuum atmosphere chamber using a roll-to-roll method. The vacuum atmosphere chamber has a membrane travel section at its front end and an electron beam irradiation section at its rear end.

[0290] An electron beam irradiation unit located at the rear end of the vacuum atmosphere chamber irradiates the traveling primary porous membrane with an electron beam. The porous polymer membrane crosslinked by the electron beam irradiation is discharged from the vacuum atmosphere chamber. The discharged porous polymer membrane is added to an additional vacuum atmosphere chamber, where it is wound into a roll by a winding roller installed in the additional vacuum atmosphere chamber.

[0291] The electron beam irradiation conditions are as follows.

[0292] Acceleration voltage: 1MeV - Single dose: 100kGy Therefore, a porous polymer membrane with a thickness of 10 μm is manufactured by winding it into a roll.

[0293] The porosity of the primary porous membrane was measured as follows.

[0294] The primary porous membrane was cut into rectangles of D1cm × D2cm (thickness: T, μm), and then the mass (M, g) measured by a precision balance and the PET skeleton density (ρ, g / cm³) were used. 3 The following formula is used to calculate .

[0295] Porosity = {1 - (M × 10000) / (D1 × D2 × T × ρ)} Examples 4 to 6, and Comparative Examples 3 and 4 In Examples 4 to 6 and Comparative Examples 3 and 4, porous polymer membranes were manufactured by the same method as described below, except that the type of non-reactive liquid was changed to that shown in Table 3 below.

[0296] At room temperature, a 10 μm thick primary porous membrane of polyethylene (PE) is continuously added to a liquid processing chamber and a nitrogen atmosphere chamber via a roll-to-roll method. The liquid processing chamber is a liquid-filled chamber filled with the non-reactive liquid listed in Table 3, and the primary porous membrane is transported while immersed in the non-reactive liquid. An electron beam irradiation unit is provided inside the nitrogen atmosphere chamber.

[0297] An electron beam is used to irradiate the primary porous membrane traveling in the nitrogen (N2) atmosphere chamber. The cross-linked porous polymer membrane irradiated by the electron beam is then discharged from the nitrogen atmosphere chamber. The discharged porous polymer membrane is then wound into a roll by a winding roller under atmospheric conditions.

[0298] Within approximately 60 seconds (approximately 30 seconds) of the primary porous membrane being discharged from the liquid processing chamber, it is irradiated with an electron beam.

[0299] The electron beam irradiation conditions are as follows.

[0300] Acceleration voltage: 1MeV - Single dose: 100kGy Therefore, a porous polymer membrane with a thickness of 10 μm is manufactured by winding it into a roll.

[0301] Examples 7 and 8, and Comparative Examples 5 and 6 In Examples 7 and 8, and Comparative Examples 5 and 6, the porous polymer membranes were manufactured by the same method as described below, except that the suction pressure and travel time of the suction roller provided at the front end of the inert gas atmosphere chamber were changed as shown in Table 4 below.

[0302] At room temperature, a primary porous membrane of polyethylene (PE) with a thickness of 10 μm is added to a nitrogen (N2) atmosphere chamber via a roll-to-roll method. The nitrogen atmosphere chamber has an intake roller at its front end and an electron beam irradiation unit at its rear end.

[0303] An electron beam is used to irradiate a primary porous membrane traveling in an electron beam irradiation section located at the rear end of the nitrogen atmosphere chamber. The porous polymer membrane crosslinked by the electron beam irradiation is then discharged from the nitrogen atmosphere chamber. The discharged porous polymer membrane is then wound into a roll by a winding roller under atmospheric conditions.

[0304] The primary porous membrane is irradiated with an electron beam within 60 seconds (approximately 30 seconds) of the start of the suction roller.

[0305] The electron beam irradiation conditions are as follows.

[0306] Acceleration voltage: 1MeV - Single dose: 100kGy Therefore, a porous polymer membrane with a thickness of 10 μm is manufactured by winding it into a roll.

[0307] Examples 9-1, 9-2, Reference 1-1, and Reference 1-2 Example 9-1 A primary porous membrane wound on a 6-inch paper tube is mounted on a first roll and then traveled at a speed of 100 meters per minute. The primary porous membrane is then added to the vacuum atmosphere chamber used in Example 1.

[0308] While a primary porous membrane of 100m is wound onto a second roller installed in the vacuum atmosphere chamber and equipped with a cellulose triacetate (CTA) dosimeter on its surface, an electron beam is continuously irradiated for 1 minute.

[0309] After winding 100m, a porous polymer film with a thickness of 1.8mm is wound up from the surface of the second roller.

[0310] The cumulative exposure dose over 1 minute was confirmed in a CTA dosimeter located at the surface position of the winding roller. Figure 9 This diagram illustrates the direction used to explain the process of measuring cumulative exposure in Example 9-1. In this case, the cumulative exposure over one minute can be measured in the direction indicated by the arrow.

[0311] The results are shown in Table 1 below.

[0312] Example 9-2 Following the same method as in Example 9-1, after winding a porous membrane of 300 m onto the second roller, a cellulose triacetate (CTA) dosimeter was installed. Then, while winding another 100 m, an electron beam was continuously irradiated for 1 minute.

[0313] After winding 100m, the porous polymer film is wound up from the surface of the second roller with a thickness of 7.2mm.

[0314] The cumulative exposure dose over 1 minute was confirmed using a CTA dosimeter located 5.4 mm from the surface of the winding roller. Figure 10 This diagram illustrates the direction used to explain the process of measuring cumulative exposure in Embodiment 9-2. In this case, the cumulative exposure over one minute is measured in the direction indicated by the arrow.

[0315] The results are shown in Table 1 below.

[0316] See Example 1-1 Except for the absence of electron beam irradiation, a primary porous membrane of 200 m was wound onto a winding roller using the same method as in Example 9-1. Then, while further winding the primary porous membrane for another 100 m, it was continuously irradiated with an electron beam for 1 minute.

[0317] After winding 100m, the porous polymer film is wound up from the surface of the second roller with a thickness of 5.4mm.

[0318] The cumulative exposure dose over 1 minute is confirmed in a CTA dosimeter located at the surface position of the winding roller.

[0319] The results are shown in Table 1 below.

[0320] See Example 1-2 Except for the absence of electron beam irradiation, a primary porous membrane of 300 m was wound onto a winding roller using the same method as in Example 9-1. Then, while further winding the primary porous membrane for another 100 m, it was continuously irradiated with an electron beam for 1 minute.

[0321] After winding 100m, the porous polymer film is wound up from the surface of the second roller with a thickness of 7.2mm.

[0322] The cumulative exposure dose over 1 minute is confirmed in a CTA dosimeter located at the surface position of the winding roller.

[0323] Figure 11 This diagram illustrates the direction used to explain the process of measuring cumulative exposure in Reference Examples 1-1 and 1-2. In this case, the cumulative exposure over one minute is measured in the direction indicated by the arrow.

[0324] For reference, in Reference Examples 1-1 and 1-2, before further winding 100m while irradiating the electron beam, 200m and 300m were wound up respectively without irradiation of the electron beam. Otherwise, the measurement process of the cumulative irradiation was the same, and therefore is shown in a figure.

[0325] The results are shown in Table 1 below.

[0326] [Table 1] Referring to Table 1, in Example 9-1, the primary porous membrane on the surface of the winding roller is treated to give it a cumulative irradiation dose of 100 kGy.

[0327] In Example 9-2, at the 300m winding position, the cumulative irradiation dose per minute was also measured to be 100kGy, which indicates that the entire area of ​​the primary porous membrane can be cured at an almost uniform level during the continuous winding process of the winding roller.

[0328] According to Reference Examples 1-1 and 1-2, as the winding length of the primary porous membrane increases, the thickness of the porous polymer membrane wound onto the surface of the winding roller (second roller) gradually increases. Therefore, the electron beam irradiation amount reaching the surface of the primary porous membrane on the second roller gradually decreases. Specifically, after the primary porous membrane is wound for 300 m, even when irradiated with an electron beam during further winding, the cumulative irradiation amount on the surface of the second roller is confirmed to be 0 kGy, thus confirming that the electron beam has not reached the surface.

[0329] Experimental Example Experimental Example 1: Oxygen Replacement Rate (1) In Examples 1 to 3 and Comparative Examples 1 and 2, the total volume (V) of each membrane was reduced before the primary porous membrane was added to the vacuum atmosphere chamber. F Multiply by porosity (R) P To calculate pore volume (V) P ), the pore volume (V P Substituting the atmospheric absolute pressure of approximately 101.325 kPa, the room temperature of approximately 298.15 K, and the gas constant (R) of 8.314 J / mol·K into the ideal gas law (PV=nRT), the total number of moles of gas in the pores (n) can be calculated. T)".

[0330] The total number of moles of gas in the pores (n) T Multiply by approximately 0.21 the mole fraction of oxygen in the atmosphere (n) O This allows us to calculate the total number of moles of oxygen present in the pores (n). I )".

[0331] The increase in oxygen partial pressure (P) caused by the removal of oxygen from the primary porous membrane in the vacuum atmosphere chamber is measured. O ).

[0332] The increase in the partial pressure of the oxygen (P) O The effective volume (V) of the vacuum atmosphere chamber C The internal temperature (T) of the vacuum atmosphere chamber C Substituting the gas constant (R) of 8.314 J / mol·K into the ideal gas law, we can calculate the total number of moles of oxygen removed from the pores (n). F )".

[0333] The total number of moles of oxygen removed from the pores (n) F ) and the total number of moles of oxygen present in the pores (n I The proportion of (n) F / n I The percentage of oxygen replacement rate is calculated as 0.

[0334] (2) In Examples 4 to 6 and Comparative Examples 3 and 4, before the primary porous membrane was added to the liquid processing chamber, the total number of moles of oxygen present in the pores (n) was calculated using the same method as described above. I ).

[0335] The increase in oxygen partial pressure (P) caused by the removal of oxygen from the primary porous membrane in the liquid processing chamber is measured. O ).

[0336] The increase in the partial pressure of the oxygen (P) O The effective volume (V) of the liquid processing chamber C The internal temperature (T) of the liquid processing chamber C Substituting the gas constant (R) of 8.314 J / mol·K into the ideal gas law, we can calculate the total number of moles of oxygen removed from the pores (n). F )".

[0337] The total number of moles of oxygen removed from the pores (n) F ) and the total number of moles of oxygen present in the pores (n I The percentage of the proportion is calculated as the oxygen replacement rate.

[0338] (3) In Examples 7 and 8, and Comparative Examples 5 and 6, before the primary porous membrane was added to the nitrogen atmosphere chamber, the total number of moles of oxygen present in the pores (n) was calculated using the same method as described above. I ).

[0339] The increase in oxygen partial pressure (P) caused by the removal of oxygen from the primary porous membrane in the nitrogen atmosphere chamber was measured. O ).

[0340] The increase in oxygen partial pressure (P) O The effective volume (V) of the nitrogen atmosphere chamber C The internal temperature (T) of the nitrogen atmosphere chamber C Substituting the gas constant (R) of 8.314 J / mol·K into the ideal gas law, we can calculate the total number of moles of oxygen removed from the pores (n). F )".

[0341] The total number of moles of oxygen removed from the pores (n) F ) and the total number of moles of oxygen present in the pores (n I The percentage of the proportion is calculated as the oxygen replacement rate.

[0342] Experimental Example 2: Puncture Strength The puncture strength of the porous polymer membrane was measured using an INSTRON Universal Test Machine (model 3345). An indentation probe with a pin tip (1.0 mm in diameter and 0.5 mm radius of curvature) was used in the test, and the indentation speed was set to 120 mm / min.

[0343] Cut the porous polymer membrane sample into 50mm × 50mm pieces and secure it flat to the lower fixture of the testing machine. Use a clamping device to secure the sample edges to prevent detachment and wrinkling.

[0344] The probe is moved perpendicular to the membrane surface, and the resulting force-displacement curve is recorded. The puncture strength is evaluated by dividing the maximum load (N) at the location of the first membrane rupture by the membrane thickness (μm) (N / μm).

[0345] All samples were stabilized for at least 24 hours at 25±2℃ and 50±5% relative humidity before being used in the test.

[0346] Experimental Example 3: Melting Fracture Temperature The thermal-mechanical stability of porous polymer membranes was evaluated using a thermomechanical analyzer (TMA).

[0347] The test was conducted by heating the specimen to a maximum of 220°C at a heating rate of 5°C / min under a constant load of 0.015N.

[0348] The temperature at which the membrane specimen breaks due to heat under tension during the test is evaluated as the melting break temperature. The breakage point is determined by the rapid stretching, breakage, or sharp change in the TMA displacement curve of the specimen.

[0349] All samples were stabilized for at least 24 hours at 25±2℃ and 50±5% relative humidity before being used in the test.

[0350] [Table 2] Referring to Table 2, the porous polymer membrane according to the embodiments is manufactured by a manufacturing method including the following process: the primary porous membrane is subjected to vacuum index I V The material passes through a vacuum atmosphere chamber under conditions meeting 0.1 or higher. The crosslinking reaction of the porous polymer membrane according to the embodiment via electron beam irradiation proceeds effectively without oxygen-induced free radical consumption and / or byproduct generation, resulting in high puncture strength and melt fracture temperature.

[0351] The porous polymer membranes of the comparative example have lower puncture strength and melt fracture temperature due to the generation of factors such as oxygen free radicals that hinder the crosslinking reaction under electron beam irradiation.

[0352] [Table 3] In Table 3, the boiling points of ethanol, acetone, propylene glycol, ethylene glycol, and deionized water are approximately 78°C, approximately 56°C, approximately 188°C, approximately 197°C, and approximately 100°C, respectively.

[0353] Referring to Table 3, the porous polymer membrane according to the embodiments is manufactured by a manufacturing method including the following process: the primary porous membrane is impregnated with index I L The liquid treatment chamber is used under conditions meeting 0.8 or higher. The crosslinking reaction of the porous polymer membrane according to the embodiment via electron beam irradiation proceeds effectively without oxygen-induced free radical consumption and / or byproduct generation, resulting in high puncture strength and melt fracture temperature.

[0354] The porous polymer membranes in the comparative example failed to undergo the cross-linking reaction via electron beam irradiation due to oxygen free radicals, resulting in lower puncture strength and melt fracture temperature.

[0355] [Table 4] Referring to Table 4, the porous polymer membrane according to the embodiments is manufactured by a manufacturing method including the following process: the primary porous membrane at an absorption index I S Under conditions satisfying 1 or higher, the suction roller passes through the inert gas atmosphere chamber. The crosslinking reaction of the porous polymer membrane according to the embodiment via electron beam irradiation proceeds effectively without oxygen-induced free radical consumption and / or byproduct generation, thus resulting in high puncture strength and melt fracture temperature.

[0356] The porous polymer membranes in the comparative example failed to undergo the cross-linking reaction via electron beam irradiation due to oxygen free radicals, resulting in lower puncture strength and melt fracture temperature.

Claims

1. A method for manufacturing a porous polymer membrane, comprising the following steps: Prepare a vacuum atmosphere chamber at the rear end of the chamber, including an electron beam irradiation unit; and The first primary porous membrane (Type 1A) is added to the vacuum atmosphere chamber. Wherein, the first A primary porous membrane satisfies the vacuum index I defined by the following formula 1. V Under conditions ranging from 0.1 to 3000, the vacuum atmosphere chamber is filled. [Formula 1] I V =(V2 / V1)×(1 / 100) In Equation 1, V1 represents the vacuum level in the vacuum atmosphere chamber, and its unit is Torr; V2 represents the travel time of the first A primary porous membrane after it is added to the vacuum atmosphere chamber until it is irradiated by the electron beam by the electron beam irradiation unit, and its unit is seconds.

2. The method for manufacturing a porous polymer membrane according to claim 1, wherein, In Equation 1, V1 is 1.0 × 10 -6 Up to 7.6×10 2 Entrust.

3. The method for manufacturing a porous polymer membrane according to claim 1, wherein, In Equation 1, V2 ranges from 1 second to 180 seconds.

4. The method for manufacturing a porous polymer membrane according to claim 1, wherein, The manufacturing method further includes the step of irradiating the first A primary porous membrane with an electron beam in the electron beam irradiation section.

5. The method for manufacturing a porous polymer membrane according to claim 4, wherein, The first primary porous membrane is wound in the electron beam irradiation section, and the wound first primary porous membrane is irradiated with an electron beam.

6. A method for manufacturing a porous polymer membrane, comprising the step of adding a first B primary porous membrane into a liquid treatment chamber filled with a non-reactive liquid or sprayed with a non-reactive liquid. in, The first B primary porous membrane satisfies the impregnation index I defined by the following formula 2. L Under conditions where the concentration is 0.8 or higher, the liquid passes through the liquid processing chamber. [Equation 2] Yo L =L2 / L1 In Equation 2, L1 represents the surface tension of the non-reactive liquid, in mN / m, and L2 represents the surface energy of the first B primary porous membrane, in mN / m.

7. The method for manufacturing a porous polymer membrane according to claim 6, wherein, In Equation 2, L1 is below 80 mN / m.

8. The method for manufacturing a porous polymer membrane according to claim 6, wherein, In Equation 2, L2 is below 80 mN / m.

9. The method for manufacturing a porous polymer membrane according to claim 6, wherein, The manufacturing method further includes the step of irradiating a second B primary porous membrane discharged from the liquid processing chamber with an electron beam.

10. The method for manufacturing a porous polymer membrane according to claim 9, wherein, The second primary porous membrane is wound in the electron beam irradiation section, and the wound second primary porous membrane is irradiated with an electron beam.

11. A method for manufacturing a porous polymer membrane, comprising the following steps: An inert gas atmosphere chamber is prepared, comprising an intake roller at the front end and an electron beam irradiation section at the rear end. as well as The first-stage porous membrane (C1) is added to the inert gas atmosphere chamber. Wherein, the first C primary porous membrane satisfies the inhalation index I defined by the following formula 3. S Traveling on the suction roller under conditions of 1 or higher, [Formula 3] I S =(S1×S2) / 100 In Equation 3, S1 represents the suction pressure of the suction roller, in mmAq, and S2 represents the time required for the first C primary porous membrane to travel on the suction roller, in seconds.

12. The method for manufacturing a porous polymer membrane according to claim 11, wherein, In Equation 3, S1 is below 5000 mmAq.

13. The method for manufacturing a porous polymer membrane according to claim 11, wherein, In Equation 3, S2 ranges from 0.1 seconds to 20 seconds.

14. The method for manufacturing a porous polymer membrane according to claim 11, wherein, The manufacturing method further includes the step of irradiating the first C primary porous membrane with an electron beam in the electron beam irradiation section.

15. The method for manufacturing a porous polymer membrane according to claim 14, wherein, The first C primary porous membrane is wound in the electron beam irradiation section, and the wound first C primary porous membrane is irradiated with an electron beam.

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