CN116103837B - A high temperature resistant polyimide composite diaphragm and preparation method thereof - Google Patents
A high temperature resistant polyimide composite diaphragm and preparation method thereof Download PDFInfo
- Publication number
- CN116103837B CN116103837B CN202310090745.0A CN202310090745A CN116103837B CN 116103837 B CN116103837 B CN 116103837B CN 202310090745 A CN202310090745 A CN 202310090745A CN 116103837 B CN116103837 B CN 116103837B
- Authority
- CN
- China
- Prior art keywords
- parts
- polyimide
- magnesium
- composite diaphragm
- temperature resistant
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Classifications
-
- D—TEXTILES; PAPER
- D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
- D01F—CHEMICAL FEATURES IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS; APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OF CARBON FILAMENTS
- D01F6/00—Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof
- D01F6/88—Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof from mixtures of polycondensation products as major constituent with other polymers or low-molecular-weight compounds
- D01F6/94—Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof from mixtures of polycondensation products as major constituent with other polymers or low-molecular-weight compounds of other polycondensation products
-
- D—TEXTILES; PAPER
- D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
- D01D—MECHANICAL METHODS OR APPARATUS IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS
- D01D5/00—Formation of filaments, threads, or the like
- D01D5/0007—Electro-spinning
- D01D5/0015—Electro-spinning characterised by the initial state of the material
-
- D—TEXTILES; PAPER
- D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
- D01D—MECHANICAL METHODS OR APPARATUS IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS
- D01D5/00—Formation of filaments, threads, or the like
- D01D5/0007—Electro-spinning
- D01D5/0061—Electro-spinning characterised by the electro-spinning apparatus
-
- D—TEXTILES; PAPER
- D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
- D01D—MECHANICAL METHODS OR APPARATUS IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS
- D01D5/00—Formation of filaments, threads, or the like
- D01D5/0007—Electro-spinning
- D01D5/0061—Electro-spinning characterised by the electro-spinning apparatus
- D01D5/0092—Electro-spinning characterised by the electro-spinning apparatus characterised by the electrical field, e.g. combined with a magnetic fields, using biased or alternating fields
-
- D—TEXTILES; PAPER
- D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
- D01F—CHEMICAL FEATURES IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS; APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OF CARBON FILAMENTS
- D01F1/00—General methods for the manufacture of artificial filaments or the like
- D01F1/02—Addition of substances to the spinning solution or to the melt
- D01F1/10—Other agents for modifying properties
-
- D—TEXTILES; PAPER
- D04—BRAIDING; LACE-MAKING; KNITTING; TRIMMINGS; NON-WOVEN FABRICS
- D04H—MAKING TEXTILE FABRICS, e.g. FROM FIBRES OR FILAMENTARY MATERIAL; FABRICS MADE BY SUCH PROCESSES OR APPARATUS, e.g. FELTS, NON-WOVEN FABRICS; COTTON-WOOL; WADDING ; NON-WOVEN FABRICS FROM STAPLE FIBRES, FILAMENTS OR YARNS, BONDED WITH AT LEAST ONE WEB-LIKE MATERIAL DURING THEIR CONSOLIDATION
- D04H1/00—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres
- D04H1/40—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties
- D04H1/42—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties characterised by the use of certain kinds of fibres insofar as this use has no preponderant influence on the consolidation of the fleece
- D04H1/4326—Condensation or reaction polymers
-
- D—TEXTILES; PAPER
- D04—BRAIDING; LACE-MAKING; KNITTING; TRIMMINGS; NON-WOVEN FABRICS
- D04H—MAKING TEXTILE FABRICS, e.g. FROM FIBRES OR FILAMENTARY MATERIAL; FABRICS MADE BY SUCH PROCESSES OR APPARATUS, e.g. FELTS, NON-WOVEN FABRICS; COTTON-WOOL; WADDING ; NON-WOVEN FABRICS FROM STAPLE FIBRES, FILAMENTS OR YARNS, BONDED WITH AT LEAST ONE WEB-LIKE MATERIAL DURING THEIR CONSOLIDATION
- D04H1/00—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres
- D04H1/70—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres characterised by the method of forming fleeces or layers, e.g. reorientation of fibres
- D04H1/72—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres characterised by the method of forming fleeces or layers, e.g. reorientation of fibres the fibres being randomly arranged
- D04H1/728—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres characterised by the method of forming fleeces or layers, e.g. reorientation of fibres the fibres being randomly arranged by electro-spinning
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/10—Energy storage using batteries
Landscapes
- Engineering & Computer Science (AREA)
- Textile Engineering (AREA)
- Mechanical Engineering (AREA)
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Manufacturing & Machinery (AREA)
- Compositions Of Macromolecular Compounds (AREA)
Abstract
The invention discloses a high-temperature-resistant polyimide composite diaphragm which comprises, by mass, 3-94 parts of polyimide, 1.5-2.5 parts of (14-16 parts of (1-2 parts of) and 0.5-1 part of (565-603 parts of) polyimide, a magnesium plastic reinforcing agent, a silane coupling agent, a ceramic powder, an organic silicon wetting dispersing agent, and an organic solvent. The polyimide composite membrane has better thermal stability, air permeability and stretchability, and the mutual coordination of all substances in the membrane can promote the increase of the crosslinking degree, thereby reducing the tension of the solution and being particularly suitable for the preparation method of electrostatic spinning.
Description
Technical Field
The invention relates to the technical field of diaphragms, in particular to a high-temperature-resistant polyimide composite diaphragm and a preparation method thereof.
Background
Nowadays, lithium ion batteries have become the most common energy device for 3C products (computer, communication, consumer Electronics), and long service life with high capacity and stable charge and discharge performance has been pursued by engineers for lithium ion batteries, and consumers for lithium ion batteries, and diaphragms are the key points of pursuits and expectations.
The conventional binder in the diaphragm is mainly PVDF organic polymer, and the PVDF organic polymer binder has good electrochemical stability, can form gel electrolyte with electrolyte, and accelerates migration of lithium ions. Although PVDF in an aqueous solvent system is more environmentally friendly, it is still significantly insufficient in high temperature resistance under extreme conditions, resulting in a decrease in the performance of the separator, thereby affecting the electrochemical performance and safety performance of the battery. Although the bonding strength between the diaphragm and the pole piece and the thermal stability of the diaphragm can be improved to a certain extent by adding polyimide and ceramic powder, the defects of uneven coated diaphragm, poor contact among ceramic powder particles, reduced elasticity of the diaphragm due to the addition of ceramic powder, easy occurrence of brittle fracture and the like still exist, so that the improvement of the electrochemical performance of the battery is limited. There are researchers trying to use a preparation method of electrostatic spinning to promote dispersion uniformity among particles through high voltage, but due to poor wettability of solid particles such as ceramic powder particles, the effect of improving electrochemical performance of a battery by using a membrane prepared by the preparation method of electrostatic spinning is not remarkable.
Disclosure of Invention
Aiming at the problems in the prior art, the invention discloses a high-temperature-resistant polyimide composite diaphragm and a preparation method thereof, the composite diaphragm comprises polyimide and ceramic powder, the invention not only can improve the bonding strength between the diaphragm and a pole piece, the thermal stability of the diaphragm can be improved, the elasticity of the diaphragm is increased, the situation that the diaphragm is broken in a brittle manner is reduced, the wettability of ceramic powder is enhanced, and the composite diaphragm with more uniform distribution and better electrochemical performance is obtained through the preparation method of electrostatic spinning.
The invention is realized by the following technical scheme:
The invention provides a high-temperature-resistant polyimide composite diaphragm which comprises, by mass, polyimide, a magnesium plastic reinforcing agent, a silane coupling agent, ceramic powder, an organosilicon wetting dispersant, an isocyanate catalyst and an organic solvent, wherein the mass ratio of the polyimide to the magnesium plastic reinforcing agent to the silane coupling agent to the ceramic powder to the organosilicon wetting dispersant to the isocyanate catalyst to the organic solvent is (93-94 parts) 3-5 parts 1.5 parts 14-16 parts 1-2 parts 0.5-1 parts 565-603 parts.
The polyimide has better thermal stability and bonding strength, ceramic powder has certain mechanical properties, and ceramic powder particles have poorer dispersibility due to poorer wettability, while polyimide belongs to polymers and has higher viscosity, so that the dispersibility of the ceramic powder is promoted to be poorer. Therefore, the organic silicon wetting dispersant is added in the invention, so that on one hand, the wettability of the ceramic powder can be promoted, and the dispersibility of the ceramic powder can be improved, and on the other hand, the viscosity of the polyimide can be reduced, so that the ceramic powder and the polyimide are further promoted to be mixed more uniformly, and the tension of the solution is promoted to be reduced. The plastic reinforcing agent is further selected to be capable of being crosslinked with polyimide, so that the tensile strength and toughness of the diaphragm are improved, but the plastic reinforcing agent is possibly not strong in crosslinking reaction with polyimide due to the fact that the plastic reinforcing agent is strong in hydrophilicity, therefore, the silane coupling agent which is the same as the organosilicon wetting dispersing agent is selected to be beneficial to promoting the dissolution of the magnesium plastic reinforcing agent in an organic solvent, magnesium is easier to be matched with the silane coupling agent, ceramic powder and the organosilicon wetting dispersing agent, so that the dissolution of the magnesium plastic reinforcing agent is promoted, the crosslinking reaction of the plastic reinforcing agent and polyimide is facilitated, the catalyst with isocyanate groups is beneficial to the crosslinking reaction of the magnesium plastic reinforcing agent and polyimide, the isocyanate groups have unsaturated bonds, the activity is high, the magnesium plastic reinforcing agent and polyimide can be used as a bridge for crosslinking of the magnesium plastic reinforcing agent, and the structural stability of the crosslinked magnesium plastic reinforcing agent and polyimide can be improved. The composite diaphragm prepared by the design has stronger heat resistance and toughness, and can reduce the situation of brittle fracture of the composite diaphragm.
As a further scheme, the magnesium plastic reinforcing agent comprises one or more of basic magnesium sulfate whisker, magnesium hydroxide whisker, magnesium carbonate whisker and magnesium borate whisker. The magnesium plastic reinforcing agent has excellent reinforcing and toughening performance, can elastically bear larger stress deformation and has smaller expansion coefficient, and can better perform crosslinking reaction with polyimide under the cooperation of the silane coupling agent and the isocyanato catalyst, thereby improving the toughness of the diaphragm.
As a further aspect, the silane coupling agent includes one or more of methyltriethoxysilane, γ -aminopropyl triethoxysilane, γ -aminopropyl trimethoxysilane, γ - (β -aminoethyl) aminopropyl trimethoxysilane, 3-acryloxypropyl trimethoxysilane, 3-methacryloxypropyl trimethoxysilane, 3-acryloxypropyl triethoxysilane, 3-methacryloxypropyl triethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, allyltrimethoxysilane, allyltriethoxysilane, bis (2-hydroxyethyl) -3-aminopropyl-methoxysilane, N-hydroxymethyl-N-methylamine-propyl trimethoxysilane, hydroxymethyl triethoxysilane, triethoxysilylmethanol, N- (3-ethoxypropylsilyl) -4-hydroxybutyramide, N- (3-ethoxypropylsilyl) -glucamide, 2-bis (3-ethoxypropylsilyl-methyl) -butanol, 2-carboxyethyltriethoxysilane.
As a further scheme, the ceramic powder comprises one or more of aluminum oxide, nano silicon dioxide, barium titanate, lead zirconate titanate, modified lead zirconate titanate, lead metaniobate, lead barium lithium niobate, lead lanthanum zirconate titanate, modified lead titanate, lead titanate-lead magnesium niobate, aluminum oxide and titanium dioxide.
As a further proposal, the organosilicon wetting dispersant comprises one or more of BYKJET-9133, BYKJET-9142, BYKJET-9151, BYKJET-9152, DISPERBYK-167, DISPERBYK-190, DISPERBYK-191 and DISPERBYK-2200. The magnesium plastic reinforcing agent has smaller tension, is favorable for infiltrating ceramic powder, can promote uniform dispersion among substances, and can be mutually fused with a silane coupling agent, so that the magnesium plastic reinforcing agent is promoted to be dissolved in a mixed solution, and the magnesium plastic reinforcing agent and polyimide are favorable for crosslinking reaction.
As a further aspect, the isocyanato-based catalyst comprises triphenylmethane triisocyanate. The phenyl-containing acetate catalyst has an electron-withdrawing effect, so that the phenyl-containing acetate catalyst forms an electron-withdrawing effect with electrons in the magnesium plastic reinforcing agent, and the triphenylmethane triisocyanate is easier to be used as a bridge for the crosslinking reaction of the magnesium plastic reinforcing agent and polyimide.
As a further scheme, the organic solvent comprises one of dimethylformamide and N-methylpyrrolidone.
The invention also provides a preparation method of the composite diaphragm.
The preparation method comprises the steps of adding diluted silane coupling agent into magnesium plastic reinforcing agent, stirring, adding isocyanato catalyst, polyimide, ceramic powder and organosilicon wetting dispersant into a mixture of the magnesium plastic reinforcing agent and the silane coupling agent under ultrasonic, drying the obtained product, dissolving the dried product in organic solvent, carrying out electrostatic spinning on a base film, enabling a needle point of a syringe to have a certain distance from a receiving surface of the base film, and pushing the syringe at a certain speed to obtain the polyimide diaphragm. The method of the invention can lead the crosslinking degree of polyimide and plastic reinforcing agent to be increased on the premise of uniform dispersion under the condition of mutual coordination of all substances, thereby reducing excessive solution tension when carrying out electrostatic spinning under high pressure, and obtaining the membrane with high heat resistance, strength, certain tensile strength and viscosity by uniform dispersion on the surface layer of the base membrane.
The silane coupling agent is diluted by absolute ethyl alcohol, the stirring temperature is 110-130 ℃, the stirring time is 25-35 min, the ultrasonic condition is 18-20 KHZ frequency, the ultrasonic time is 20-30 min, the drying time is 25-35 min, the drying temperature is 75-85 ℃, the voltage of electrostatic spinning is 14-16 Kv, the distance between a needle point of a syringe and a receiving surface of a base film is 14cm-16cm, the advancing speed of the syringe is 0.4-0.6 mL/h, and the electrostatic spinning time is 2.4-2.6 h.
The polyimide composite membrane has the characteristics and beneficial effects that the polyimide composite membrane has better thermal stability, air permeability and stretchability, and the mutual coordination of all substances in the polyimide composite membrane can promote the increase of the crosslinking degree, so that the tension of a solution is reduced, and the polyimide composite membrane is particularly suitable for a preparation method of electrostatic spinning.
Detailed Description
In order to facilitate understanding of one of the high temperature resistant polyimide composite membranes of the present invention, the following more complete description of the composite membrane of the present invention will be given, without thereby limiting the scope of the invention.
(1) A process for producing polyimide comprises synthesizing a polyimide from diaminodiphenyl sulfone (DDS) and bisphenol A dianhydride (BPADA) in a molar ratio of 1:1 at 180 ℃. Direct purchase of existing polyimide drugs may also be employed.
(2) Adding a silane coupling agent diluted by ethanol into a magnesium plastic reinforcing agent, stirring at 110-130 ℃ for 25-35 min in a high-speed stirrer, pouring the mixture into an ultrasonic dispersing instrument, adding an isocyanato catalyst, polyimide powder, ceramic powder and an organosilicon wetting dispersant for crosslinking reaction at the ultrasonic frequency of 18KHZ-20KHZ for 20-30 min, and drying the obtained product at 75-85 ℃ for 25-35 min in an oven to obtain the dried product. And (3) dissolving the dried product in NMP organic solvent, spinning in a high-voltage electrostatic field with the voltage of 14Kv-16Kv, wherein the distance from the needle point of a syringe to a receiving surface is 14cm-16cm, the advancing speed of the syringe is controlled to be 0.4mL/h-0.6mL/h, and the electrospinning time is 2.4h-2.6h, so that the heat-resistant polyimide diaphragm is prepared.
Wherein, the magnesium plastic reinforcing agent comprises one or more of basic magnesium sulfate whisker, magnesium hydroxide whisker, magnesium carbonate whisker and magnesium borate whisker.
The silane coupling agent includes one or more of methyltriethoxysilane, gamma-aminopropyl triethoxysilane, gamma-aminopropyl trimethoxysilane, gamma- (beta-aminoethyl) aminopropyl trimethoxysilane, 3-acryloxypropyl trimethoxysilane, 3-methacryloxypropyl trimethoxysilane, 3-acryloxypropyl triethoxysilane, 3-methacryloxypropyl triethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, allyltrimethoxysilane, allyltriethoxysilane, bis (2-hydroxyethyl) -3-aminopropyl-methoxysilane, N-hydroxymethyl-N-methylamine-propyltrimethoxysilane, hydroxymethyl triethoxysilane, triethoxysilylmethanol, N- (3-ethoxypropylsilyl) -4-hydroxybutyramide, N- (3-ethoxypropylsilyl) -glucamide, 2-bis (3-ethoxypropylsilyl-methyl) -butanol, 2-carboxyethyltriethoxysilane.
The ceramic powder comprises one or more of aluminum oxide, nano silicon dioxide, barium titanate, lead zirconate titanate, modified lead zirconate titanate, lead metaniobate, lead barium lithium niobate, lead lanthanum zirconate titanate, modified lead titanate, lead-magnesium niobate titanate, aluminum oxide and titanium dioxide.
The organosilicon wetting dispersant comprises one or more of BYKJET-9133, BYKJET-9142, BYKJET-9151, BYKJET-9152, DISPERBYK-167, DISPERBYK-190, DISPERBYK-191 and DISPERBYK-2200.
The isocyanato-based catalyst comprises triphenylmethane triisocyanate.
We further compared the performance comparisons between the polyimide composite membrane obtained by the present invention and other membranes.
Example 1:
2g of methyltriethoxysilane diluted by absolute ethyl alcohol is added into 4g of basic magnesium sulfate whisker, stirred for 30 minutes at 120 ℃ in a high-speed stirrer, poured into an ultrasonic dispersion instrument, and added with 0.5g of triphenylmethane triisocyanate, 93.5g of polyimide powder, 15g of aluminum oxide and BYKJET-91331.5g of catalyst under the condition of 19KHZ frequency for ultrasonic treatment for 25 minutes to carry out crosslinking reaction. The resulting product was dried in an oven at 80 ℃ for 30 minutes. The final product is obtained. The final product was dissolved in 565g of NMP organic solvent, spun in a high voltage electrostatic field at a voltage of 15kv, the distance from the tip of the syringe to the receiving surface was 15cm, the advancing speed of the syringe was controlled at 0.5ml/h, and the electrospinning time was 2.5 hours, to prepare a heat-resistant polyimide separator.
Example 2:
2g of vinyl triethoxysilane diluted by absolute ethyl alcohol is added into 4g of magnesium hydroxide whisker, the mixture is stirred for 30 minutes at 120 ℃ in a high-speed stirrer, the mixture is poured into an ultrasonic dispersing instrument, the ultrasonic treatment time is 25 minutes, 0.5g of triphenylmethane triisocyanate, 93.5g of polyimide powder, 15g of nano silicon dioxide and BYKJET-91421.5g of catalyst are added at 19KHZ frequency, and the crosslinking reaction is carried out. The resulting product was dried in an oven at 80 ℃ for 30 minutes. The final product is obtained. The final product was dissolved in 565g of NMP organic solvent, spun in a high voltage electrostatic field at a voltage of 15kv, the distance from the tip of the syringe to the receiving surface was 15cm, the advancing speed of the syringe was controlled at 0.5ml/h, and the electrospinning time was 2.5 hours, to prepare a heat-resistant polyimide separator.
Example 3:
2g of hydroxymethyl triethoxysilane diluted by absolute ethyl alcohol is added into 4g of magnesium carbonate whisker, the mixture is stirred for 30 minutes at 120 ℃ in a high-speed stirrer, the mixture is poured into an ultrasonic dispersing instrument, the ultrasonic treatment time is 25 minutes, and 0.5g of triphenylmethane triisocyanate, 93.5g of polyimide powder, 15g of barium titanate and 1671.5g of DISPERBYK are added under the 19KHZ frequency to carry out crosslinking reaction. The resulting product was dried in an oven at 80 ℃ for 30 minutes. The final product is obtained. The final product was dissolved in 565g of NMP organic solvent, spun in a high voltage electrostatic field at a voltage of 15kv, the distance from the tip of the syringe to the receiving surface was 15cm, the advancing speed of the syringe was controlled at 0.5ml/h, and the electrospinning time was 2.5 hours, to prepare a heat-resistant polyimide separator.
Example 4:
2g of allyl trimethoxysilane diluted by absolute ethyl alcohol is added into 4g of magnesium borate whisker, the mixture is stirred for 30 minutes at 120 ℃ in a high-speed stirrer, the mixture is poured into an ultrasonic dispersion instrument, the ultrasonic treatment time is 25 minutes, 0.5 percent g of triphenylmethane triisocyanate, 93.5 percent g of polyimide powder, 15g of titanium dioxide and 1911.5g of DISPERBYK are added under the 19KHZ frequency, and the crosslinking reaction is carried out. The resulting product was dried in an oven at 80 ℃ for 30 minutes. The final product is obtained. The final product is dissolved in 565gNMP organic solvent, spun in a high-voltage electrostatic field with voltage of 15kv, the distance from the needle point of a syringe to the receiving surface is 15cm, the advancing speed of the syringe is controlled at 0.5ml/h, and the electrospinning time is 2.5 hours, thus preparing the heat-resistant polyimide diaphragm.
Comparative example 1:
93.5% g of polyimide powder, 15g of aluminum oxide and BYKJET-91331.5g are dissolved in 565gNMP organic solvent, spun in a high-voltage electrostatic field with voltage of 15kv, the distance from the needle point of a syringe to the receiving surface is 15cm, the advancing speed of the syringe is controlled at 0.5ml/h, and the electrospinning time is 2.5 hours, so that the heat-resistant polyimide diaphragm is prepared.
Comparative example 2:
2g of methyltriethoxysilane diluted by absolute ethyl alcohol is added into 4g of basic magnesium sulfate whisker, stirred for 30 minutes at 120 ℃ in a high-speed stirrer, poured into an ultrasonic dispersing instrument, and subjected to crosslinking reaction by adding 93.5% g of polyimide powder, 15g of aluminum oxide and BYKJET-91331.5g under the ultrasonic condition for 25 minutes and 19KHZ frequency. The resulting product was dried in an oven at 80 ℃ for 30 minutes. The final product is obtained. The final product is dissolved in 565gNMP organic solvent, spun in a high-voltage electrostatic field with voltage of 15kv, the distance from the needle point of a syringe to the receiving surface is 15cm, the advancing speed of the syringe is controlled at 0.5ml/h, and the electrospinning time is 2.5 hours, thus preparing the heat-resistant polyimide diaphragm.
Comparative example 3:
0.1g of methyltriethoxysilane diluted by absolute ethyl alcohol is added into 4g of basic magnesium sulfate whisker, stirred for 30 minutes at 120 ℃ in a high-speed stirrer, poured into an ultrasonic dispersion instrument, and added with 0.5g of triphenylmethane triisocyanate, 93.5g of polyimide powder, 15g of aluminum oxide and BYKJET-91331.5g of catalyst under the condition of 19KHZ frequency for ultrasonic treatment for crosslinking reaction. The resulting product was dried in an oven at 80 ℃ for 30 minutes. The final product is obtained. The final product is dissolved in 565gNMP organic solvent, spun in a high-voltage electrostatic field with voltage of 15kv, the distance from the needle point of a syringe to the receiving surface is 15cm, the advancing speed of the syringe is controlled at 0.5ml/h, and the electrospinning time is 2.5 hours, thus preparing the heat-resistant polyimide diaphragm.
Comparative example 4:
2g of methyltriethoxysilane diluted by absolute ethyl alcohol is added into 2g of basic magnesium sulfate whisker, stirred for 30 minutes at 120 ℃ in a high-speed stirrer, poured into an ultrasonic dispersion instrument, and added with 0.5g of triphenylmethane triisocyanate, 93.5g of polyimide powder, 15g of aluminum oxide and BYKJET-91331.5g of catalyst under the condition of 19KHZ frequency for ultrasonic treatment for 25 minutes to carry out crosslinking reaction. The resulting product was dried in an oven at 80 ℃ for 30 minutes. The final product is obtained. The final product is dissolved in 565gNMP organic solvent, spun in a high-voltage electrostatic field with voltage of 15kv, the distance from the needle point of a syringe to the receiving surface is 15cm, the advancing speed of the syringe is controlled at 0.5ml/h, and the electrospinning time is 2.5 hours, thus preparing the heat-resistant polyimide diaphragm.
Comparative example 5:
2g of methyltriethoxysilane diluted by absolute ethyl alcohol is added into 6g of basic magnesium sulfate whisker, stirred for 30 minutes at 120 ℃ in a high-speed stirrer, poured into an ultrasonic dispersion instrument, and added with 0.5g of triphenylmethane triisocyanate, 93.5g of polyimide powder, 15g of aluminum oxide and BYKJET-91331.5g of catalyst under the condition of 19KHZ frequency for ultrasonic treatment for 25 minutes to carry out crosslinking reaction. The resulting product was dried in an oven at 80 ℃ for 30 minutes. The final product is obtained. The final product is dissolved in 565gNMP organic solvent, spun in a high-voltage electrostatic field with voltage of 15kv, the distance from the needle point of a syringe to the receiving surface is 15cm, the advancing speed of the syringe is controlled at 0.5ml/h, and the electrospinning time is 2.5 hours, thus preparing the heat-resistant polyimide diaphragm.
Comparative example 6:
2g of methyltriethoxysilane diluted by absolute ethyl alcohol is added into 1g of basic magnesium sulfate whisker, stirred for 30 minutes at 120 ℃ in a high-speed stirrer, poured into an ultrasonic dispersion instrument, and subjected to crosslinking reaction by adding 0.5% g of triphenylmethane triisocyanate, 93.5g of polyimide powder, 15g of aluminum oxide and BYKJET-91331.5g of catalyst under the condition of 19KHZ frequency for 25 minutes. The resulting product was dried in an oven at 80 ℃ for 30 minutes. The final product is obtained. The final product is dissolved in 565gNMP organic solvent, spun in a high-voltage electrostatic field with voltage of 15kv, the distance from the needle point of a syringe to the receiving surface is 15cm, the advancing speed of the syringe is controlled at 0.5ml/h, and the electrospinning time is 2.5 hours, thus preparing the heat-resistant polyimide diaphragm.
Comparative example 7:
2g of methyltriethoxysilane diluted by absolute ethyl alcohol is added into 6g of basic magnesium sulfate whisker, stirred for 30 minutes at 120 ℃ in a high-speed stirrer, poured into an ultrasonic dispersion instrument, and added with 0.5g of triphenylmethane triisocyanate, 93.5g of polyimide powder, 15g of aluminum oxide and BYKJET-91331.5g of catalyst under the condition of 19KHZ frequency for ultrasonic treatment for crosslinking reaction. The resulting product was dried in an oven at 80 ℃ for 30 minutes. The final product is obtained. The final product is dissolved in 700gNMP organic solvent, spun in a high-voltage electrostatic field with the voltage of 15kv, the distance from the needle point of a syringe to the receiving surface is 15cm, the advancing speed of the syringe is controlled at 0.5ml/h, and the electrospinning time is 2.5 hours, so that the heat-resistant polyimide diaphragm is prepared.
Comparative example 8:
2g of methyltriethoxysilane diluted by absolute ethyl alcohol is added into 7g of basic magnesium sulfate whisker, stirred for 30 minutes at 120 ℃ in a high-speed stirrer, poured into an ultrasonic dispersion instrument, and added with 0.5g of triphenylmethane triisocyanate, 93.5g of polyimide powder, 15g of aluminum oxide and BYKJET-91331.5g of catalyst under the condition of 19KHZ frequency for ultrasonic treatment for crosslinking reaction. The resulting product was dried in an oven at 80 ℃ for 30 minutes. The final product is obtained. The final product is dissolved in 700gNMP organic solvent, spun in a high-voltage electrostatic field with the voltage of 15kv, the distance from the needle point of a syringe to the receiving surface is 15cm, the advancing speed of the syringe is controlled at 0.5ml/h, and the electrospinning time is 2.5 hours, so that the heat-resistant polyimide diaphragm is prepared.
Comparative example 9:
2g of methyltriethoxysilane diluted by absolute ethyl alcohol is added into 4g of basic magnesium sulfate whisker, stirred for 30 minutes at 120 ℃ in a high-speed stirrer, poured into an ultrasonic dispersion instrument, and added with 0.5g of triphenylmethane triisocyanate, 93.5g of polyimide powder, 15g of aluminum oxide and BYKJET-91331.5g of catalyst under the condition of 19KHZ frequency for ultrasonic treatment for 25 minutes to carry out crosslinking reaction. The resulting product was dried in an oven at 80 ℃ for 30 minutes. The final product is obtained. The final product is dissolved in 200gNMP organic solvent, spun in a high-voltage electrostatic field with voltage of 15kv, the distance from the needle point of a syringe to the receiving surface is 15cm, the advancing speed of the syringe is controlled at 0.5ml/h, and the electrospinning time is 2.5 hours, thus preparing the heat-resistant polyimide diaphragm.
Comparative example 10:
2g of methyltriethoxysilane diluted by absolute ethyl alcohol is added into 4g of basic magnesium sulfate whisker, stirred for 30 minutes at 120 ℃ in a high-speed stirrer, poured into an ultrasonic dispersion instrument, and added with 0.5g of triphenylmethane triisocyanate, 93.5g of polyimide powder, 15g of aluminum oxide and BYKJET-91331.5g of catalyst under the condition of 19KHZ frequency for ultrasonic treatment for 25 minutes to carry out crosslinking reaction. The resulting product was dried in an oven at 80 ℃ for 30 minutes. The final product is obtained. The final product is dissolved in 300gNMP organic solvent, spun in a high-voltage electrostatic field with voltage of 15kv, the distance from the needle point of a syringe to the receiving surface is 15cm, the advancing speed of the syringe is controlled at 0.5ml/h, and the electrospinning time is 2.5 hours, thus preparing the heat-resistant polyimide diaphragm.
We also tested the separators prepared in the examples and comparative examples, principally comprising the following test methods:
(1) The thermal shrinkage of the membrane was measured by the method described in GB/T2027-2004.
(2) The tensile strength of the diaphragm is measured according to GB/T2040.3-2006.
(3) The puncture strength of the diaphragm is detected by the method of GB/T23318-2009.
(4) The viscosity of the final mixed solution was measured by the method described in GB/T5561-2012.
(5) The air permeability value of the diaphragm is measured by the method of GB/T36363-2018.
Verification result analysis
Table 1 comparison of example and comparative example diaphragms
| - | Example 1 | Example 2 | Example 3 | Example 4 | Comparative example 1 | Comparative example 2 | Comparative example 3 | Comparative example 4 | Comparative example 5 | Comparative example 6 | Comparative example 7 | Comparative example 8 | Comparative example 9 | Comparative example 10 |
| Degree of crosslinking/ρ | 5.30% | 5% | 5% | 5.10% | - | 1% | 1.80% | 3.60% | 2.50% | 3.60% | 2.70% | 2.50% | 5% | 5% |
| 200 ℃ Per 1h heat shrinkage | 0.40% | 0.50% | 0.50% | 0.40% | 1.20% | 0.50% | 0.60% | 0.60% | 0.70% | 0.60% | 0.70% | 0.80% | 0.40% | 0.40% |
| Tensile Strength/mp | 96.8 | 95.8 | 96.1 | 96.2 | 60.5 | 76.9 | 82.3 | 90.6 | 89.5 | 90.9 | 89.5 | 88.8 | 91.4 | 91.6 |
| Puncture strength/N | 5.7 | 5.5 | 5.6 | 5.7 | 4.8 | 4.1 | 4.3 | 5.1 | 4.8 | 5.1 | 5 | 4.9 | 5.4 | 5.2 |
| Viscosity of mixed solution at 25℃per pa.s | 35.4 | 35.6 | 35.2 | 35.3 | 41.2 | 35.6 | 34.8 | 35.2 | 36.7 | 35.4 | 33.8 | 32.7 | 82.1 | 105.6 |
| Ventilation value | 175.3 | 170.4 | 173.5 | 173.3 | 150.4 | 174.6 | 176.3 | 173.5 | 173.6 | 175.8 | 204.2 | 206.3 | 131.5 | 128.3 |
The polyimide composite diaphragm is successfully obtained by an electrostatic spinning method, and the polyimide composite diaphragm prepared by the method is tested, and the test results are shown in table 1. The performance of the composite diaphragm obtained by the invention is superior to that of a comparative example, and the organosilicon wetting agent can promote the wettability of ceramic powder, so that the dispersibility of the ceramic powder in polyimide is improved, and the magnesium plastic reinforcing agent is added, so that the magnesium plastic reinforcing agent can be subjected to crosslinking reaction with polyimide, the silane coupling agent which is the same as the organosilane wetting agent is further added, the solubility of the magnesium plastic reinforcing agent is promoted, and under the action of the isocyanate catalyst, the silane coupling agent is crosslinked with polyimide, and the isocyanate catalyst can be used as a bridge for crosslinking the magnesium reinforcing agent and the polyimide, thereby being beneficial to improving the tensile strength and toughness of the composite diaphragm, and also overcoming the occurrence of brittle rupture of the diaphragm caused by solid particles such as ceramic powder. Through the mutual coordination of the materials, the battery diaphragm with good air permeability, thermal stability and tensile strength is successfully obtained by adopting an electrostatic spinning method.
We have further compared the conventional manner of preparing polyimide separator, as shown in examples 1-4 and comparative example 1, it has been found that the magnesium plastic reinforcing agent of the present invention facilitates the compounding of polyimide and ceramic powder, thereby reducing the thermal shrinkage of the separator and improving the puncture strength and air permeability of the separator. The magnesium plastic reinforcing agent and polyimide are considered to be related to crosslinking, and after the magnesium plastic reinforcing agent and polyimide are crosslinked, the tension of the solution is reduced, so that the mixed solution is uniformly adhered to a base film in an electrostatic spinning mode, the magnesium plastic reinforcing agent can also enhance the tensile strength of the diaphragm, the occurrence of brittle fracture of the diaphragm is reduced, and the safety performance of a battery is improved.
On this basis, we further studied the effect of the interactions between the individual substances of the present invention on the degree of improvement in the performance of the battery separator, as shown in examples 1-4 and comparative examples 2-10. When the amount of the magnesium plastic reinforcing agent added is changed, the crosslinking of the magnesium plastic reinforcing agent with the polyimide is directly affected, and as shown in comparative examples 4 to 6, when the amount of the magnesium plastic reinforcing agent added is too much (comparative example 5) or too little (comparative examples 4 and 6), the degree of crosslinking is lowered, probably because the crosslinking is too low when the amount of the magnesium plastic reinforcing agent added is too small, and when the amount of the magnesium plastic reinforcing agent added is too much, the crosslinking reaction is not sufficiently completed because the isocyanate-based catalyst is relatively small, resulting in lowering the degree of crosslinking. Furthermore, we have further found that the isocyanate-based catalyst and the silane coupling agent have a greater influence on the degree of crosslinking, as in comparative examples 2 to 3, and that the reaction of the magnesium plastic reinforcing agent and the polyimide is adversely affected when the isocyanate-based catalyst is not added or the silane coupling agent is reduced, and that it is considered that the decrease in the silane coupling agent affects the solubility of the magnesium plastic reinforcing agent and the crosslinking of the polyimide directly, and that the decrease in the silane coupling agent directly affects the crosslinking degree of the magnesium plastic reinforcing agent and the polyimide, because the bridge material is absent when the isocyanate-based catalyst is absent. Therefore, when the isocyanate-based catalyst or the silane coupling agent is reduced or absent, the crosslinking of the magnesium plastic reinforcing agent and the polyimide is decreased linearly, and the tensile strength, puncture strength and heat shrinkage of the separator are all affected.
We have further found that the amount of organic solvent added directly affects the viscosity of the solution during static electricity prevention, and thus the tension of the solution, and thus the air permeability of the battery separator prepared by electrospinning. When the concentration of the solution is too high, the viscosity rise results in a lower air permeability value of the final separator, while when the concentration is too low, the viscosity drop results in a higher air permeability value of the separator, as shown in comparative examples 7-10, and either too high or too low air permeability value of the separator is detrimental to the performance of the separator. In summary, we further select the mass ratio of polyimide, magnesium plastic reinforcing agent, silane coupling agent, ceramic powder, organosilicon wetting dispersant, isocyanato catalyst, and organic solvent to be (93-94 parts) (3-5 parts) (1.5-2.5 parts) (14-16 parts) (1-2 parts) (0.5-1 parts) (565-603 parts).
In summary, the preparation method of the present invention can obtain a battery separator having excellent air permeability, thermal stability and tensile strength.
It should be noted that the above-mentioned embodiments are only preferred embodiments of the present invention, and are not intended to limit the present invention, and any modifications, equivalent substitutions, improvements, etc. within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (8)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310090745.0A CN116103837B (en) | 2023-02-09 | 2023-02-09 | A high temperature resistant polyimide composite diaphragm and preparation method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310090745.0A CN116103837B (en) | 2023-02-09 | 2023-02-09 | A high temperature resistant polyimide composite diaphragm and preparation method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN116103837A CN116103837A (en) | 2023-05-12 |
| CN116103837B true CN116103837B (en) | 2025-06-10 |
Family
ID=86267071
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202310090745.0A Active CN116103837B (en) | 2023-02-09 | 2023-02-09 | A high temperature resistant polyimide composite diaphragm and preparation method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN116103837B (en) |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101355143A (en) * | 2007-07-27 | 2009-01-28 | 比亚迪股份有限公司 | A kind of battery diaphragm and preparation method thereof |
| KR101656760B1 (en) * | 2015-12-23 | 2016-09-13 | (주)상아프론테크 | Nonwoven for porous separation membrane of secondary battery, Porous separation membrane of secondary battery using the same and Manufacturing method thereof |
| CN107641460A (en) * | 2017-09-30 | 2018-01-30 | 惠州佳合能新能源科技有限公司 | A kind of functional coating material component of electrokinetic cell barrier film and preparation method thereof |
| CN112787042A (en) * | 2020-04-24 | 2021-05-11 | 深圳市劢全新材料科技有限责任公司 | Lithium battery diaphragm and preparation method thereof |
Family Cites Families (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH11345681A (en) * | 1998-06-03 | 1999-12-14 | Co-Op Chem Co Ltd | Planar heating element |
| US7981509B2 (en) * | 2006-02-13 | 2011-07-19 | Donaldson Company, Inc. | Polymer blend, polymer solution composition and fibers spun from the polymer blend and filtration applications thereof |
| US7935745B2 (en) * | 2007-03-27 | 2011-05-03 | Case Western Reserve University | Self-assembled nanofiber templates; versatile approaches for polymer nanocomposites |
| JP4798148B2 (en) * | 2008-02-08 | 2011-10-19 | ソニー株式会社 | Battery pack and manufacturing method thereof |
| JP2011183236A (en) * | 2010-03-04 | 2011-09-22 | Kureha Ltd | Method for manufacturing filter medium for heat-resistant filter having bulkiness, and heat-resistant filter using the filter medium |
| WO2014142450A1 (en) * | 2013-03-14 | 2014-09-18 | (주)에프티이앤이 | Method for preparing porous separation membrane for second battery and porous separation membrane for second battery prepared thereby |
| CN107008166B (en) * | 2017-03-22 | 2020-07-07 | 同济大学 | A kind of nanocomposite moisture permeable membrane and its preparation method and application |
| CN111293262A (en) * | 2020-03-18 | 2020-06-16 | 溧阳天目先导电池材料科技有限公司 | Composite diaphragm capable of reducing thermal runaway risk of lithium battery, preparation method and lithium battery |
| CN112086681B (en) * | 2020-09-28 | 2021-10-08 | 中国石油大学(华东) | A kind of preparation method of organic/inorganic composite lithium-ion battery solid-state electrolyte material |
| CN113651612A (en) * | 2021-08-13 | 2021-11-16 | 湖州南木纳米科技有限公司 | Barium titanate PTC thermal sensitive ceramic material and application thereof in lithium battery |
-
2023
- 2023-02-09 CN CN202310090745.0A patent/CN116103837B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101355143A (en) * | 2007-07-27 | 2009-01-28 | 比亚迪股份有限公司 | A kind of battery diaphragm and preparation method thereof |
| KR101656760B1 (en) * | 2015-12-23 | 2016-09-13 | (주)상아프론테크 | Nonwoven for porous separation membrane of secondary battery, Porous separation membrane of secondary battery using the same and Manufacturing method thereof |
| CN107641460A (en) * | 2017-09-30 | 2018-01-30 | 惠州佳合能新能源科技有限公司 | A kind of functional coating material component of electrokinetic cell barrier film and preparation method thereof |
| CN112787042A (en) * | 2020-04-24 | 2021-05-11 | 深圳市劢全新材料科技有限责任公司 | Lithium battery diaphragm and preparation method thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| CN116103837A (en) | 2023-05-12 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP2929580B1 (en) | Solid composite fluoropolymer layer | |
| CN107353871B (en) | High-temperature-resistant bonding sealing silicone resin and preparation method thereof | |
| CN110797494A (en) | A kind of separator functional coating material for lithium ion battery and preparation method thereof | |
| CN102898573B (en) | Siloxane-containing vinyl chloride copolymer, preparation method of the siloxane-containing vinyl chloride copolymer, battery division plate prepared from the siloxane-containing vinyl chloride copolymer, and manufacturing method of the battery division plate | |
| CN104086772A (en) | Uramido modified MQ silicon resin, and preparation method and application thereof | |
| CN109929141A (en) | A kind of graphene oxide and its epoxy nano composite material of polyethyleneimine-modified | |
| WO2024027006A1 (en) | Low-toxicity single-component silicone sealant for photovoltaic frame and preparation method therefor | |
| CN109880295A (en) | An amino-terminated modified graphene oxide and its epoxy nanocomposite | |
| CN105237810A (en) | Phosphorus-nitrogen nano flame retardant of core-shell structure and preparation method thereof | |
| WO2021023309A1 (en) | Nonwoven fabric separator, and preparation method therefor and application thereof | |
| CN116103837B (en) | A high temperature resistant polyimide composite diaphragm and preparation method thereof | |
| CN109148794B (en) | Oily ceramic slurry for diaphragm, preparation method of oily ceramic slurry and diaphragm | |
| CN111653715B (en) | A kind of modified ceramic separator and preparation method thereof and lithium ion battery | |
| CN111423596A (en) | A kind of traceable auxiliary agent and preparation method thereof | |
| CN109830727A (en) | A kind of chitosan/quaternized attapulgite clay compounded proton exchange membrane and preparation method thereof | |
| WO2025156883A1 (en) | Method for preparing thermally-resistant thermally-insulating organosilicon aerogel material on the basis of piers-rubinsztajn reaction | |
| CN118834583A (en) | Epoxy silica gel flame-retardant ceramic fireproof paint and preparation method thereof | |
| WO2025036143A1 (en) | Secondary battery binder, negative electrode slurry, electrode sheet, and secondary battery | |
| CN118879024A (en) | A fast curing epoxy resin and preparation method thereof | |
| CN106486638B (en) | Battery insulating ring, preparation method thereof and power battery using insulating ring | |
| CN116606469A (en) | Flame-retardant film material with strong mechanical property and preparation method thereof | |
| CN103756260B (en) | A kind of biomass modified thermosetting resin and preparation method thereof | |
| CN110776664B (en) | A kind of condensation type organosilicon resin aerogel and preparation method thereof | |
| CN119613969B (en) | Anti-aging organic silicon foaming material and preparation method thereof | |
| CN115926583A (en) | Environment-friendly modified epoxy resin coating and preparation method thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |