Quaternized triazole imide polymer, preparation method and application thereof, quaternized triazole imide battery diaphragm and application thereof

Abstract

The invention provides a quaternized triazole imide polymer, a preparation method and application thereof, a quaternized triazole imide battery diaphragm and application, and belongs to the technical field of imide materials. The quaternized triazole imide polymer provided by the invention not only has excellent heat resistance, the glass transition temperature (Tg) is 260-271 DEG C, the Td < 5% > reaches 532.9-553.2 DEG C, and the Td < 10% > reaches 543.6-564.2 DEG C, but also can be dissolved in common organic solvents (DMSO, DMF and DMAc), and has excellent processability; the material has excellent conductivity, the room temperature conductivity is 4.1 * 10 <-6 >-9.2 * 10 <-6 > S.cm <-1 >, the thermal conductivity is good, the thermal conductivity is 0.49-0.7 W. (m.K) <-1 >, and the material can be applied to the fields of ultrathin semiconductor packaging, battery diaphragms, liquid crystal displays, light emitting diodes and the like.

Description

Technical Field

[0001] The present invention relates to the technical field of imide materials, and in particular to a quaternized triazole imide polymer and a preparation method and application thereof, and a quaternized triazole imide battery separator and application thereof. Background Art

[0002] With the rapid development of intelligent power systems such as electric vehicles and microelectronic devices, lithium batteries have become the only choice for high-performance batteries due to their high energy density and cycle stability. Lithium batteries are composed of cathodes, anodes, electrolytes and separators, among which the separator plays a key role because it directly affects the cycle performance and safety of the battery. At present, commercial lithium battery separators are mainly polyolefin materials, such as polyethylene and polypropylene. Polyolefin separators have certain electrochemical stability and mechanical properties, and are cheap and non-toxic, suitable for actual production. However, polyolefin materials as separators also have some limitations and disadvantages. The high polarity leads to poor compatibility with the electrolyte, which may cause safety problems and low ionic conductivity. The large heat shrinkage rate at high temperature and poor thermal stability can easily cause fire and explosion, which cannot meet the growing high performance and safety requirements, limiting the long-term use of this material. Therefore, it is urgent to solve the problems of traditional commercial lithium battery separators due to their poor thermal stability and low ionic conductivity.

[0003] Nitrogen heterocyclic polymer materials containing imide rings on the main chain have higher bond energies of carbon-nitrogen bonds and imide bonds, making polymers of this structure more difficult to break at high temperatures, and exhibiting extremely strong thermal stability and thermal decomposition temperature. For example, patent CN118507980B provides a sponge-like polyimide battery separator with good thermal stability, simple synthesis, and high structural uniformity. For example, patent CN115353622 B discloses a poly 1,5-substituted triazole with good processability and high thermal stability, and a variety of functional groups can be introduced. However, the poor thermal stability of lithium battery separators and the problem of unsafe and easy ignition due to poor thermal conductivity have not yet been solved. Summary of the invention

[0004] The purpose of the present invention is to provide a quaternized triazole imide polymer and a preparation method and application thereof, a quaternized triazole imide battery separator and application thereof, so as to overcome the problem that the existing battery separator has poor thermal stability and poor thermal conductivity, which causes unsafe and flammable properties.

[0005] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions: The present invention provides a quaternized triazole imide polymer having a structure shown in Formula I: Formula I; In Formula I, R is , or ; Ar ; X is I, Br or Cl; n is an integer ranging from 21 to 45.

[0006] The present invention provides a method for preparing the quaternized triazole imide polymer described in the above technical solution, comprising the following steps: The aromatic imine triazole polymer with the structure shown in formula II, an alkylating agent and an organic solvent are mixed to carry out a nucleophilic substitution reaction to obtain a quaternary ammonium triazole imide polymer; The alkylating agent is methyl iodide, methyl bromide or methyl chloride; Formula II; In formula II, R is , or ; Ar ; n is an integer ranging from 21 to 45.

[0007] Preferably, the molar ratio of the aromatic imine triazole polymer to the alkylating agent is 1:(2-5).

[0008] Preferably, the temperature of the nucleophilic substitution reaction is 50-100° C. and the time is 12-36 h.

[0009] Preferably, the organic solvent includes dimethyl sulfoxide, N,N-dimethylformamide, N,N-dimethylacetamide or N-methylpyrrolidone.

[0010] The present invention provides the application of the quaternized triazole imide polymer described in the above technical solution or the quaternized triazole imide polymer prepared by the preparation method described in the above technical solution in the fields of ultra-thin semiconductor packaging, battery separators, liquid crystal displays or light-emitting diodes.

[0011] The invention provides a quaternized triazole imide battery separator, which is prepared by a film drawing method, a flow-casting method or a spin coating method using the quaternized triazole imide polymer described in the above technical scheme.

[0012] The present invention provides the use of the quaternized triazole imide battery separator described in the above technical solution in the preparation of a heat-resistant lithium battery separator.

[0013] The invention provides a quaternized triazole imide polymer, in which the rigid and flexible groups in the main chain of the polymer play different roles. The main chain structure has rigid imide rings and triazole rings, which limit the free rotation and movement of the molecular chain, improve the thermal stability of the polymer, increase the decomposition temperature, thereby improving the heat resistance, and can improve the mechanical properties of the polymer; the presence of flexible groups such as ether bonds and methylene groups increases the mobility of the molecular chain, can better disperse stress when subjected to external forces, and improve the solubility of the polymer. The introduction of a quaternary ammonium group containing a positive charge into the polymer chain increases the ion concentration, improves the ion mobility, improves the conductivity of the film, and can increase the wettability with the electrolyte. Moreover, the introduction of positive ions can inhibit phonon scattering and reduce interfacial thermal resistance through electrostatic action, improve thermal conductivity, and therefore is not prone to fire under high temperature conditions, and is relatively safe. Therefore, the battery separator made of the quaternized triazole imide of the invention solves the problems of poor solubility and poor thermal conductivity of commercial battery separators at the same time, and improves the safety performance of the separator by improving thermal conductivity without reducing thermal stability.

[0014] The high bond energy of the nitrogen heterocyclic structure in the triazole ring leads to strong thermal stability, and the nitrogen atom is highly nucleophilic and easy to undergo substitution reactions; the present invention introduces the imide ring and the triazole ring into the main chain at the same time, which can not only improve the thermal stability of the polymer material, but also introduce reaction sites to improve the solubility and conductivity of the material. Specifically, the quaternized triazole imide of the present invention not only has excellent heat resistance, the glass transition temperature (Tg) is 260~271℃, T d5% Reach 532.9~553.2℃, T d10% It can reach 543.6~564.2℃ and is soluble in common organic solvents (DMSO, DMF, DMAc). It has excellent processability and excellent electrical conductivity. The room temperature electrical conductivity is 4.1×10 -6 ~9.2×10 -6 S cm -1 , good thermal conductivity, thermal conductivity is 0.49~0.7 W·(m·K) -1 As a battery separator, it has good ion transmission performance and safety for high-temperature use.

[0015] The invention uses aromatic imine triazole polymer and alkylating agent to efficiently prepare quaternary ammonium triazole imide with high yield and mild reaction conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 FT-IR graph of CDCl3 of quaternized triazole imide polymer in Examples 1 to 3; Figure 2 The DSC curves of the quaternized triazole imide polymers prepared in Examples 1 to 3; Figure 3 is the TGA graph of the quaternized triazole imide polymer prepared in Examples 1 to 3; Figure 4 [PTAI-n] in Examples 1 to 3 + I - The conductivity diagram of Figure 5 [PTAI-n] in Examples 1 to 3 + I - Plot of thermal conductivity at different temperatures. DETAILED DESCRIPTION

[0017] In the present invention, unless otherwise specified, the required raw materials or reagents are commercially available products well known to those skilled in the art.

[0018] The present invention provides a quaternized triazole imide polymer having a structure shown in Formula I: Formula I; In Formula I, R is , or ; Ar ; X is I, Br or Cl; n is an integer ranging from 21 to 45.

[0019] In the present invention, n is more preferably 26-40, and even more preferably 28-32.

[0020] In the present invention, the quaternized triazole imide polymer is preferably , or .

[0021] The present invention provides a method for preparing the quaternized triazole imide polymer described in the above technical solution, comprising the following steps: The aromatic imine triazole polymer with the structure shown in formula II, an alkylating agent and an organic solvent are mixed to carry out a nucleophilic substitution reaction to obtain a quaternary ammonium triazole imide polymer; The alkylating agent is methyl iodide, methyl bromide or methyl chloride; Formula II; In formula II, R is , or ; Ar ; n is an integer ranging from 21 to 45.

[0022] In the present invention, the aromatic imine triazole polymer with the structure shown in formula II is preferably prepared according to the method described in patent CN 119161734 A, and the dianhydride monomer with the structure shown in formula III in the patent is replaced by bisphenol A diether dianhydride.

[0023] In addition, when R in Formula I of the present invention is When the 4,4'-diazide compound in the diamine monomer preparation raw material having the structure shown in formula II in patent CN 119161734 A is replaced with 4,4'-diazide diphenylmethane; the 4,4'-diazide diphenylmethane is prepared by the method disclosed in Example 4 of patent CN118684885A.

[0024] In the present invention, the alkylating agent has a structure shown in Formula III: Formula III.

[0025] In formula II, Y is I, Br or Cl.

[0026] In the present invention, the molar ratio of the aromatic imine triazole polymer to the alkylating agent is preferably 1:(2-5), more preferably 1:3.

[0027] In the present invention, the organic solvent preferably includes dimethyl sulfoxide, N,N-dimethylformamide, N,N-dimethylacetamide or N-methylpyrrolidone. The present invention has no particular limitation on the amount of the organic solvent, which can be adjusted according to actual needs to ensure smooth reaction.

[0028] In the present invention, the aromatic imine triazole polymer is preferably dissolved in an organic solvent, an alkylating agent is added, and the reaction is carried out in a light-shielding condition.

[0029] In the present invention, the temperature of the nucleophilic substitution reaction is preferably 50-100° C., more preferably 60-80° C., and the time is preferably 12-36 h, more preferably 24 h.

[0030] After the nucleophilic substitution reaction is completed, the present invention preferably precipitates in deionized water and filters, and the filter cake is repeatedly washed with deionized water and anhydrous ethanol until the pH of the filtrate is 7, and freeze-dried to obtain a quaternized triazole imide polymer. The present invention has no special restrictions on the filtration, washing and drying, and can be carried out in a manner well known in the art.

[0031] The present invention provides the application of the quaternized triazole imide polymer described in the above technical solution or the quaternized triazole imide polymer prepared by the preparation method described in the above technical solution in the fields of ultra-thin semiconductor packaging, battery separators, liquid crystal displays or light-emitting diodes.

[0032] The invention provides a quaternized triazole imide battery separator, which is prepared by a film drawing method, a flow-casting method or a spin coating method using the quaternized triazole imide polymer described in the above technical scheme.

[0033] The present invention has no special limitation on the film drawing, casting and spin coating, and the quaternized triazole imide can be made into a thin film according to the process well known in the art. In the embodiment of the present invention, the quaternized triazole imide is dissolved in anhydrous DMAc to obtain a solution with a solid content of 15 wt%, cast on a clean glass plate, treated in a vacuum drying oven at 100°C / 2h, and then immersed in deionized water after cooling to room temperature, and peeled and dried to obtain a quaternized triazole imide film.

[0034] The present invention provides the use of the quaternized triazole imide battery separator described in the above technical solution in the preparation of a heat-resistant lithium battery separator. The present invention has no special limitation on the method of the application, and the application can be carried out according to methods well known in the art.

[0035] The specific embodiments of the present invention are described in detail below, but it should be understood that the protection scope of the present invention is not limited by the specific embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work belong to the protection scope of the present invention. The experimental methods described in the embodiments of the present invention are conventional methods unless otherwise specified.

[0036] The following experimental methods and detection methods, unless otherwise specified, are conventional methods; the following reagents and raw materials, unless otherwise specified, are commercially available.

[0037] Example 1 (1) Add 0.01 mol of 4,4'-diazide diphenyl sulfone (prepared according to patent CN 118684885 A) and 100 mL of N,N-dimethylacetamide to a 250 mL three-necked flask protected by nitrogen gas and a magnetic stirring heating device, add 0.02 mol of m-aminophenylacetylene after dissolution, and then add 0.005 mol of copper sulfate pentahydrate and 0.01 mol of sodium ascorbate in sequence, heat and stir at 60°C, react for 6 h, and after the reaction is completed, drop the obtained product solution into a stirred saturated disodium ethylenediaminetetraacetic acid aqueous solution to obtain a light yellow precipitate, filter and freeze-dry to obtain the diamine monomer Diamine-1; 0.01 mol of diamine monomer Diamine-1 and 100 mL of N,N-dimethylacetamide were added to a 250 mL three-necked flask protected by nitrogen gas and a magnetic stirring heating device. After stirring at room temperature and dissolving, 0.0102 mol of 4,4'-oxydiphthalic anhydride was added three times in an ice bath, and the reaction was continued at 5°C for 6 hours. 0.02 mol of dehydrating agent acetic anhydride and 0.01 mol of catalyst triethylamine were added, and the mixture was stirred at 25°C for 4 hours. The obtained solution was poured into deionized water for precipitation, and the solution was filtered and washed with deionized water for 3 times until the pH value of the filtrate was 7. The obtained precipitate was dried in a freeze dryer for 24 hours to obtain an aromatic imine triazole polymer, which was recorded as PTAI-1 and has the structural formula: ; (2) Add 2 mmol PTAI-1 in DMSO (20 mL) to a 50 mL three-necked flask protected by a magnetic stirring heating device and nitrogen. After the DMSO solution (20 mL) is dissolved, add 6 mmol CH3I and react at 60°C in the dark for 24 h. Precipitate in deionized water and filter. Wash the filter cake repeatedly with deionized water and anhydrous ethanol until the pH of the filtrate is 7. Freeze-dry to obtain a quaternary ammonium triazole imide polymer, which is denoted as [PTAI-1]. + I - , the structural formula is .

[0038] Example 2 (1) Add 0.01 mol of 4,4'-diazide diphenyl ether (prepared according to patent CN 118684885 A) and 100 mL of N,N-dimethylacetamide to a 250 mL three-necked flask protected by nitrogen gas and a magnetic stirring heating device, add 0.02 mol of m-aminophenylacetylene after dissolution, and then add 0.005 mol of copper sulfate pentahydrate and 0.01 mol of sodium ascorbate in sequence, heat and stir at 60°C, react for 6 h, and after the reaction is completed, drop the obtained product solution into a stirred saturated disodium ethylenediaminetetraacetic acid aqueous solution to obtain a light yellow precipitate, filter and freeze-dry to obtain the diamine monomer Diamine-2; 0.01 mol of diamine monomer Diamine-2 and 100 mL of N,N-dimethylacetamide were added to a 250 mL three-necked flask protected by nitrogen gas and a magnetic stirring heating device. After the solution was dissolved by stirring at room temperature, 0.0102 mol of 4,4'-oxydiphthalic anhydride was added three times in an ice bath, and the reaction was continued at 5°C for 6 hours. 0.02 mol of dehydrating agent acetic anhydride and 0.01 mol of catalyst triethylamine were added, and the mixture was stirred at 25°C for 4 hours. The obtained solution was poured into deionized water for precipitation, and the solution was filtered and washed with deionized water for 3 times until the pH value of the filtrate was 7. The obtained precipitated product was dried in a freeze dryer for 24 hours to obtain an aromatic imine triazole polymer PTAI-2, the structural formula of which is shown below; ; (2) Add 2 mmol PTAI-2 in DMSO (20 mL) to a 50 mL three-necked flask protected by a magnetic stirring heating device and nitrogen. After the DMSO solution is dissolved, add 6 mmol CH3I and react at 60°C in the dark for 24 h. Precipitate in deionized water and filter. Wash the filter cake repeatedly with deionized water and anhydrous ethanol until the pH of the filtrate is 7. Freeze-dry to obtain a quaternary ammonium triazole imide polymer, which is denoted as [PTAI-2]. + I - , the structural formula is .

[0039] Example 3 (1) In a flask containing 0.5948 g (3 mmol) of 4,4'-diaminodiphenylmethane, add 20 mL of deionized water and 12 mL of 12 mol / L concentrated hydrochloric acid, stir until the solid is completely dissolved and the system becomes milky white. The temperature of the mixture is controlled at 0°C under an ice bath, and 9 mL of a 1 mol / L sodium nitrite aqueous solution (0.6216 g, 9mmol), after stirring for 1h, the temperature was controlled at 0℃, and 9mL (0.4681g, 7.2mmol) of an aqueous solution of sodium azide with a concentration of 1mol / L was added dropwise, and the system gradually turned light yellow, with light yellow powder precipitated and nitrogen released. After the addition of sodium azide was completed, the system was transferred to room temperature for reaction, stirred for 3h, the reaction was stopped, and allowed to stand for 12h. It was found that the precipitate and the solution were clear, and the solid was located in the upper layer of the system. The filter cake was washed with deionized water 3 times and dried in vacuo at 50℃ for 12h to obtain a light yellow powder, and 4,4'-diazidodiphenylmethane was obtained; 0.01 mol 4,4'-diazidodiphenylmethane and 100 mL N,N-dimethylacetamide were added to a 250 mL three-necked flask protected by nitrogen gas and a magnetic stirring heating device. After dissolution, 0.02 mol m-aminophenylacetylene was added, and then 0.005 mol copper sulfate pentahydrate and 0.01 mol sodium ascorbate were added in sequence. The mixture was heated and stirred at 60°C for 6 h. After the reaction was completed, the obtained product solution was dripped into a stirred saturated disodium ethylenediaminetetraacetic acid aqueous solution to obtain a light yellow precipitate. After filtration, the precipitate was freeze-dried to obtain a diamine monomer Diamine-2. 0.01 mol of diamine monomer Diamine-3 and 100 mL of N,N-dimethylacetamide were added to a 250 mL three-necked flask protected by nitrogen gas and a magnetic stirring heating device. After the solution was dissolved by stirring at room temperature, 0.0102 mol of 4,4'-oxydiphthalic anhydride was added three times in an ice bath, and the reaction was continued at 5°C for 6 hours. 0.02 mol of dehydrating agent acetic anhydride and 0.01 mol of catalyst triethylamine were added, and the mixture was stirred at 25°C for 4 hours. The obtained solution was poured into deionized water for precipitation, and the solution was filtered and washed with deionized water for 3 times until the pH value of the filtrate was 7. The obtained precipitate was dried in a freeze dryer for 24 hours to obtain an aromatic imine triazole polymer PTAI-3, the structural formula of which is shown below; ; (2) Add 2 mmol PTAI-3 in DMSO (20 mL) to a 50 mL three-necked flask protected by a magnetic stirring heating device and nitrogen. After the DMSO solution (20 mL) is dissolved, add 6 mmol CH3I and react at 60°C in the dark for 24 h. Precipitate in deionized water and filter. Wash the filter cake repeatedly with deionized water and anhydrous ethanol until the pH of the filtrate is 7. Freeze-dry to obtain a quaternized triazole imide polymer, which is denoted as [PTAI-3]. + I - , the structural formula is .

[0040] Example 4 The CH3I in Example 1 was replaced by CH3Br, while other conditions remained unchanged, and the obtained structural formula was consistent with that in Example 1.

[0041] Example 5 The CH3I in Example 2 was replaced by CH3Cl, and other conditions remained unchanged, and the obtained structural formula was consistent with that in Example 2.

[0042] Application Example 1 The quaternized triazole imide polymers prepared in Examples 1 to 5 were respectively dissolved in anhydrous DMAc to obtain solutions with a solid content of 15 wt%, cast on a clean glass plate, and treated in a vacuum drying oven at 100° C. / 2 h. After cooling to room temperature, the glass plate was immersed in deionized water, peeled and dried to obtain a quaternized triazole imide film.

[0043] Application Example 2 The quaternized triazole imide polymers prepared in Examples 1 to 5 were respectively dissolved in anhydrous DMF to obtain a solution with a solid content of 15 wt%, and the solution was spin-coated on a clean glass plate and treated in a vacuum drying oven at 100° C. / 2 h. After cooling to room temperature, the glass plate was immersed in deionized water, peeled and dried to obtain a quaternized triazole imide film.

[0044] Application Example 3 The quaternized triazole imide polymers prepared in Examples 1 to 5 were respectively dissolved in anhydrous NMP to obtain solutions with a solid content of 15 wt%, spread on a clean glass plate by a film drawing method, and treated in a vacuum drying oven at 100° C. / 2 h. After cooling to room temperature, the glass plate was immersed in deionized water, peeled and dried to obtain a quaternized triazole imide film.

[0045] test 1) Infrared test Figure 1 is the FT-IR image of the quaternized triazole imide polymer in Examples 1 to 3, Figure 1 It can be seen that 1727cm -1 The stretching vibration peak of C=O of the ester group exists, indicating that the ester structure is not destroyed during the polymerization process. -1 and 1442cm -1 The characteristic absorption peaks of -C=C- and -N=N- in the triazole ring appeared at 3071cm -1 The vibration absorption peak of the triazole ring appears. 2931cm -1 The appearance of the methyl peak indicated that the quaternization was successful and the quaternized triazole imide polymer was successfully prepared.

[0046] 2) Thermal performance test The thermal properties of the quaternized triazole imide polymers in Examples 1 to 3 were tested.

[0047] The DSC test process and conditions are as follows: heating from 50°C to 350°C at a heating rate of 20°C / min, then cooling to 50°C at a heating rate of 20°C / min, and finally heating to 350°C at a heating rate of 20°C / min. The second heating curve is taken. The results are shown in Figure 2 and Table 1.

[0048] Figure 2is the DSC curve of the quaternized triazole imide polymer prepared in Examples 1 to 3, Figure 2 It can be seen that [PTAI-n] + I - The glass transition temperatures of all the polymers are higher than 270°C. The introduction of quaternary ammonium ions enhances the conjugation and intermolecular forces, thus resulting in a very high glass transition temperature.

[0049] The TGA process and conditions are as follows: under nitrogen atmosphere, the protective gas flow rate is 30 mL / min, the purge gas flow rate is 30 mL / min, and the temperature is increased from 50°C to 800°C at a heating rate of 20°C / min. The results are shown in Figure 3 and Table 1.

[0050] Figure 3 is the TGA diagram of the quaternized triazole imide polymer prepared in Examples 1 to 3, Figure 3 It can be seen that the mass loss is 5% (T d5% ) and mass loss of 10% (T d10% ) are higher than 530℃ and 540℃ respectively, which have higher thermal decomposition temperatures.

[0051] Table 1 Thermal performance test results of quaternized triazole imide in Examples 1 to 3

[0052] from Figure 2 , Figure 3 As shown in Table 1, [PTAI-n] + I - It has good high temperature resistance and thermal decomposition temperature.

[0053] 3) Solubility test Test Examples 1 to 3 [PTAI-1] + I - , [PTAI-2] + I - and [PTAI-3] + I - The solubility test process is as follows: Use an electronic balance to accurately weigh 0.1g [PTAI-n] + I - (n=1, 2 or 3) were added to 5 mL of different solvents (see Table 2), stirred with a magnetic stirrer at room temperature, allowed to stand for 3 h, and after the solid phase was completely precipitated, the upper solution was analyzed after 2 h. When the concentrations of the two were basically the same, the test was terminated and the solubility was compared. If no analyte remained, it was defined as completely dissolved; if the residual amount of the analyte was 1-90%, it was defined as partially dissolved; if the residual amount of the analyte was greater than 90%, it was defined as insoluble.

[0054] The test results are shown in Table 2, where "++" indicates complete dissolution; "+" indicates partial dissolution; and "-" indicates no dissolution.

[0055] Table 2 [PTAI-n] + I - Solubility test results Solvents Example 1 Example 2 Example 3 THF + + + DMSO ++ ++ ++ DMF ++ ++ ++ DMAc ++ ++ ++ <![CDATA[CH2Cl2]]> - - - acetone - - - Ethanol - - - From Table 2, we can see that the polymer [PTAI-n] + I - It has certain solubility and is soluble in most strong polar solvents. It has good processing performance and electrolyte wettability.

[0056] 4) Conductivity test For [PTAI-n] in Examples 1 to 3 + I - Conductivity test. The electrochemical impedance spectrum (EIS) of the membrane was obtained by using an electrochemical comprehensive tester (two-electrode method) using the AC impedance method, and the ionic conductivity of the membrane was calculated according to formula (1).

[0057] Where, σ (S cm -1 ) is the proton conductivity, L (cm) is the distance between the two electrodes, R (Ω) is the membrane resistance obtained from the low intersection of the high-frequency semicircle and the real axis (Z) on the complex impedance plane, and A (cm 2 ) is the cross-sectional area of ​​the test sample.

[0058] Figure 4 [PTAI-n] in Examples 1 to 3 + I - The conductivity diagram of Figure 4 It can be seen that after quaternization, the free volume in the membrane increases, thereby improving the proton conductivity of the membrane. [PTAI-2] + I - Contains a large number of ether bonds, which can weaken the electrostatic interaction between anions and cations, making it easier for anions and cations to dissociate. So at the same temperature, the conductivity [PTAI-2] + I - >[PTAI-3] + I - >[PTAI-1] + I - The corresponding room temperature ionic conductivity is 4.1×10 -6 , 9.2×10 -6 and 6.1×10 -6 S cm -1, which means that the polymer has a high ionic conductivity at room temperature. As the temperature increases from room temperature to 200 ° C, the ionic conductivity of the polymer is greatly improved, and the highest ionic conductivity reaches 2.4×10 -4 S cm -1 (200℃). This is because as the temperature increases, the movement of the chain segments accelerates, promoting the migration of ions.

[0059] 5) Thermal conductivity test For [PTAI-n] in Examples 1 to 3 + I - The thermal conductivity of the samples was tested. The thermal conductivity was measured by the laser flash method (LFA) using five shots, each lasting 30 milliseconds, and the signal was fitted by the Cape-Lehman algorithm using Netzsch's Proteus analysis software. The diameter of the test sample was 12.7 mm. The thermal conductivity was calculated using formula (2).

[0060] λ=ρ×c×α (2) Among them, λ(W·(m·K) -1 ) is thermal conductivity, ρ(g / cm 3 ), c((J / (g·K)) and α(mm 2 / s) represent density, specific heat capacity and thermal diffusion coefficient respectively.

[0061] The film was thermally annealed at 200°C for 1 h, and then taken out after returning to room temperature, and the thermal conductivity was measured again.

[0062] Figure 5 [PTAI-n] in Examples 1 to 3 + I - The thermal conductivity diagram at different temperatures is given by Figure 5 It can be seen that after quaternization, the electrostatic interaction of positive and negative charges enhances the intermolecular forces, making the polymer have excellent room temperature thermal conductivity (25°C), [PTAI-1] + I - , [PTAI-2] + I - and [PTAI-3] + I - The thermal conductivities are 0.7, 0.49 and 0.62 W·(m·K) respectively. -1 Due to the thermal annealing at 200℃, it is much lower than [PTAI-n] + I - The glass transition temperature of the composite is 0.1°, so the thermal conductivity after thermal annealing remains basically unchanged.

[0063] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A quaternized triazole imide polymer, characterized in that: It has the structure shown in formula I: Formula I; In Formula I, R is , or ; Ar ; X is I, Br or Cl; n is an integer ranging from 21 to 45.

2. The method for preparing the quaternized triazole imide polymer according to claim 1, characterized in that: The following steps are involved: The aromatic imine triazole polymer with the structure shown in formula II, an alkylating agent and an organic solvent are mixed to carry out a nucleophilic substitution reaction to obtain a quaternary ammonium triazole imide polymer; The alkylating agent is methyl iodide, methyl bromide or methyl chloride; Formula II; In Formula II, R is , or ; Ar ; n is an integer ranging from 21 to 45.

3. The preparation method according to claim 2, characterized in that: The molar ratio of the aromatic imine triazole polymer to the alkylating agent is 1:(2-5).

4. The preparation method according to claim 2, characterized in that: The temperature of the nucleophilic substitution reaction is 50-100° C. and the time is 12-36 h.

5. The preparation method according to claim 2, characterized in that: The organic solvent includes dimethyl sulfoxide, N,N-dimethylformamide, N,N-dimethylacetamide or N-methylpyrrolidone.

6. Application of the quaternized triazole imide polymer according to claim 1 or the quaternized triazole imide polymer prepared by the preparation method according to any one of claims 2 to 5 in the field of ultra-thin semiconductor packaging, battery separators, liquid crystal displays or light-emitting diodes.

7. A quaternized triazole imide battery separator, characterized in that: The quaternized triazole imide polymer according to claim 1 is prepared by film drawing method, cast flow method or spin coating method.

8. Use of the quaternized triazole imide battery separator according to claim 7 in the preparation of heat-resistant lithium battery separators.

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