A phosphorus-modified styrene-butadiene rubber polymer, a preparation method and application thereof

Abstract

The application provides a phosphorus modified butadiene styrene rubber polymer and a preparation method and application thereof. The polymer structure is that the method is: butadiene styrene rubber polymer is dissolved in a solvent to obtain a polymer glue solution; a vinyl phosphonate monomer and an initiator are added into the glue solution to carry out a free radical grafting reaction to obtain a target product. The phosphorus modified butadiene styrene rubber polymer prepared by the application has good adhesion to the pole piece and the diaphragm, good flame retardance and electrolyte swelling resistance, can improve the safety performance of the battery, and reduce the risks of battery swelling, fire and explosion.

Description

Technical Field

[0001] This invention belongs to the field of rubber modification, and particularly relates to a phosphorus-modified styrene-butadiene rubber polymer, its preparation method, and its application. Background Technology

[0002] Lithium-ion batteries are frequently used as power batteries in transportation vehicles due to their long lifespan and high energy density. However, in recent years, safety incidents related to lithium-ion batteries have occurred frequently. The main reason is that the electrolyte used in traditional liquid lithium-ion batteries is an organic solvent, and most common electrolyte components are highly flammable substances, which can easily cause fires, spontaneous combustion, and explosions. Therefore, it is necessary to mix the electrolyte and positive and negative electrode materials with adhesives that have flame-retardant properties, good adhesion, and resistance to electrolyte swelling to create safer cell materials.

[0003] Patent CN1499658A discloses an explosion-proof separator for lithium-ion secondary batteries. It incorporates a flame retardant, phosphate ester, into the separator. However, the flame retardant itself is not stable within the operating voltage range of the lithium battery, and its flame-retardant effect is unsatisfactory after long-term charge-discharge cycles.

[0004] Patent CN118336128A discloses a high-safety semi-solid-state lithium-ion battery and its preparation method. It involves reacting prepolymerized acrylates with phosphorus-containing flame-retardant monomers to obtain a gelled electrolyte membrane. However, the polymer matrix exhibits poor resistance to swelling in the electrolyte, easily leading to structural damage and performance degradation when immersed in the electrolyte. Summary of the Invention

[0005] To address the above technical problems, one objective of this invention is to provide a phosphorus-modified styrene-butadiene rubber polymer and its preparation method.

[0006] Another objective of this invention is to provide the application of the phosphorus-modified styrene-butadiene rubber polymer in the field of battery adhesives, which can improve the adhesion performance of the adhesive to the electrode sheet and separator, flame retardant performance and electrolyte swelling resistance, improve battery safety performance, and reduce the risk of battery swelling, fire and explosion.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0008] In a first aspect, the present invention provides a phosphorus-modified styrene-butadiene rubber polymer, the polymer having the structure shown in Formula 1:

[0009]

[0010] In the formula, R1 and R2 are each independently selected from H, C1-12 alkyl groups, such as methyl, ethyl, propyl, butyl, etc.; R1 and R2 can be the same or different.

[0011] x is an integer ≥ 1, preferably x is an integer between 10 and 500; y is an integer ≥ 1, preferably y is an integer between 10 and 500; z is an integer ≥ 1, preferably z is an integer between 10 and 500; m is an integer ≥ 1, preferably m is an integer between 10 and 100; n is an integer ≥ 1, preferably n is an integer between 10 and 100.

[0012] The phosphorus-modified styrene-butadiene rubber polymer of the present invention has a number average molecular weight between 5w and 100w.

[0013] The phosphorus-modified styrene-butadiene rubber polymer of this invention uses reactive monomers containing phosphorus, which are covalently introduced into the polymer backbone. This structure can better improve the flame retardant properties of solid electrolytes, preventing them from being ignited by open flames. It can also improve the safety performance of the battery cell through a free radical quenching mechanism, effectively solving problems such as poor flame retardant performance of batteries. The polymer of this invention also incorporates ester groups, hydroxyl groups, etc., which can improve the adhesion of the polymer to the electrodes and separators.

[0014] Secondly, the present invention provides a method for preparing the phosphorus-modified styrene-butadiene rubber polymer shown in Formula 1 above.

[0015] A method for preparing a phosphorus-modified styrene-butadiene rubber polymer, comprising the following steps:

[0016] S1: Add styrene-butadiene rubber polymer to a solvent, heat and stir to dissolve to obtain a rubber solution;

[0017] S2: Add vinyl phosphate monomers and initiators to the adhesive solution in step S1, and carry out a free radical grafting reaction to obtain the phosphorus-modified styrene-butadiene rubber polymer.

[0018] In one specific embodiment, the styrene-butadiene rubber polymer in step S1 has the following characteristics:

[0019] The structure shown in Equation 2:

[0020]

[0021] In the formula, the values ​​of x, y, and z are the same as in Formula 1, that is, x is an integer ≥1, preferably an integer between 10 and 500; y is an integer ≥1, preferably an integer between 10 and 500; z is an integer ≥1, preferably an integer between 10 and 500.

[0022] In a preferred embodiment, the rubber polymer is one or more of solution-polymerized styrene-butadiene rubber, emulsion-polymerized styrene-butadiene rubber, and styrene-butadiene block copolymer.

[0023] In one specific embodiment, the solvent in step S1 is a solvent that has good solubility in both styrene-butadiene rubber and vinyl phosphate monomers, preferably one or more of N,N-dimethylformamide, N,N-dimethylacetamide, ethyl acetate, dimethyl sulfoxide, and N-methylpyrrolidone.

[0024] In one specific embodiment, the styrene-butadiene rubber polymer in step S1 has a content of 5-30 wt% in the adhesive solution, such as 5 wt%, 10 wt%, 15 wt%, 20 wt%, 25 wt%, 30 wt%, etc.

[0025] In one specific implementation, the dissolution in step S1 is carried out at a temperature of 80-100℃, such as 80℃, 85℃, 90℃, 95℃, 100℃, etc., and for a time of 2-8h, such as 2h, 3h, 4h, 5h, 6h, 7h, 8h, etc.

[0026] In one specific embodiment, the vinyl phosphate monomer described in step S2 has the structure shown in Formula 3:

[0027]

[0028] In the formula, R1 and R2 are the same as in Formula 1, that is, R1 and R2 are each independently selected from H, C1-12 alkyl groups, etc.; R1 and R2 can be the same or different.

[0029] As a preferred embodiment, the vinyl phosphate monomer is a vinyl monomer with a phosphonate group, preferably one or more of vinylphosphonate dibutyl ester, vinylphosphonate dipropyl ester, vinylphosphonate diethyl ester, vinylphosphonate dimethyl ester, and vinylphosphonic acid, more preferably vinylphosphonic acid.

[0030] In one specific embodiment, the mass ratio of the vinyl phosphate monomer in step S2 to the styrene-butadiene rubber polymer in step S1 is (1-10):100, for example, 1:10, 1:20, 1:40, 1:60, 1:80, 1:100, etc.

[0031] In one specific implementation, the initiator in step S2 is any initiator that can be used to initiate free radical polymerization and copolymerization reactions of olefins and dienes, including but not limited to one or more of azo initiators, peroxide initiators, and cationic and anionic initiators;

[0032] Preferably, the initiator is selected from one or more of azobisisobutyronitrile, azobisisoheptanenitrile, azobis(dimethyl)valerate, cumene hydroperoxide, tert-butyl hydroperoxide, p-menthol hydroperoxide, potassium persulfate, ammonium persulfate, lauroyl peroxide, benzoyl peroxide, and dodecyl peroxide.

[0033] In one specific embodiment, the amount of initiator used in step S2 is 0.5-5% of the mass of the styrene-butadiene rubber polymer in step S1, for example, 0.5%, 1%, 2%, 3%, 4%, 5%, etc.

[0034] In one specific implementation, the free radical grafting reaction in step S2 is carried out under an inert protective atmosphere, such as nitrogen, argon, helium, etc.

[0035] In one specific implementation, the free radical grafting reaction in step S2 is carried out at a temperature of 80-100℃, such as 80℃, 85℃, 90℃, 95℃, 100℃, etc., and for a time of 2-6h, such as 2h, 3h, 4h, 5h, 6h, etc.

[0036] In one specific implementation, the vinyl phosphate monomer and the initiator in step S2 are added by dropping, and the dropping time is 1-4 hours, such as 1 hour, 2 hours, 3 hours, 4 hours, etc. The dropping time is not included in the aforementioned reaction time. After the dropping is completed, the reaction is kept at a constant temperature.

[0037] Thirdly, the present invention provides an application of the phosphorus-modified styrene-butadiene rubber polymer described above.

[0038] The use of a phosphorus-modified styrene-butadiene rubber polymer, wherein the polymer is the phosphorus-modified styrene-butadiene rubber polymer shown in Formula 1 above, or the phosphorus-modified styrene-butadiene rubber polymer prepared by the above method, wherein the phosphorus-modified styrene-butadiene rubber polymer is used in the field of battery adhesives.

[0039] In one specific implementation, a battery cell material with excellent flame retardant properties and good adhesion to the electrode is prepared using the aforementioned phosphorus-modified styrene-butadiene rubber polymer as a raw material.

[0040] Specifically, the battery cell material with excellent flame retardant properties and good adhesion to the electrode sheets is prepared by the following method: A battery cell material with excellent flame retardant properties and good adhesion to the electrode sheets includes a phosphorus-modified styrene-butadiene rubber polymer and a solvent (such as phosphonate-modified solution-polymerized styrene-butadiene rubber, N-methylpyrrolidone, vinyl phosphate, and self-polymers), and a negative electrode battery material such as graphite, conductive carbon black, carbon nanotubes, etc. This method is a known process in the field, and its related operations, process conditions, and the equipment used can all be carried out using conventional selections in the field. Those skilled in the art can optimize the process based on existing technology and known processes according to actual needs. This invention does not have any particular limitations in this regard. Compared with the prior art, the positive effects of this invention are:

[0041] 1) The polymer network formed can suppress volume expansion during long-term immersion in electrolyte, thus improving the safety performance of the battery;

[0042] 2) By introducing phosphorus-containing reactive monomers into the polymer skeleton in the form of covalent bonds and using them in battery cell materials, the flame retardant properties of the electrolyte can be better improved. It cannot be ignited when exposed to open flames, and the safety performance of the cell can be improved through the free radical quenching mechanism, effectively solving problems such as poor flame retardant performance of batteries.

[0043] 3) The introduction of ester groups, hydroxyl groups and other groups improves the adhesion performance of the polymer to the electrode and the diaphragm. Detailed Implementation

[0044] The present invention will be further illustrated below with specific embodiments. These embodiments are merely illustrative and do not limit the scope of the invention.

[0045] The main raw materials used in the various embodiments and comparative examples of this invention are sourced as follows. Unless otherwise specified, other raw materials and reagents were obtained through commercially available channels:

[0046] Emulsion styrene-butadiene rubber: ESBR 1500, Lee Chang Yung Chemical Industry Co., Ltd.;

[0047] Solution-polymerized styrene-butadiene rubber: SSBR 2003, Shanghai Gaoqiao Petrochemical Co., Ltd.;

[0048] Styrene-butadiene block polymer: SBS1401(YH-792E), Sinopec Baling Petrochemical Company;

[0049] N-Methylpyrrolidone: Shandong Changxin Chemical Technology Co., Ltd., purity >99%, CAS No. 872-50-4;

[0050] Ethyl acetate: Shanghai Maclean Biochemical Technology Co., Ltd., purity >99%, CAS No. 141-78-6;

[0051] N,N-Dimethylformamide: Shanghai Maclean Biochemical Technology Co., Ltd., purity >99%, CAS No. 68-12-2;

[0052] Vinylphosphoric acid: Shanghai Maclean Biochemical Technology Co., Ltd., purity >97%, CAS No. 1746-03-8;

[0053] Diethyl vinylphosphonate: Haimen Ruiyi Pharmaceutical Technology Co., Ltd., purity >97%, CAS No. 682-30-4;

[0054] Triethyl phosphonate: Shanghai Maclean Biochemical Technology Co., Ltd., purity > 99.8%, 78-40-0; Azobisisobutyronitrile: Zouping Mingxing Chemical Co., Ltd., purity > 99%, CAS No. 78-67-1;

[0055] Benzoyl peroxide: Shanghai Maclean Biochemical Technology Co., Ltd., purity >75%, CAS No. 94-36-0;

[0056] Dodecyl peroxide: Shanghai Maclean Biochemical Technology Co., Ltd., purity >75%, CAS No. 105-74-8.

[0057] The main performance analysis methods used in the embodiments and comparative examples of this invention are as follows:

[0058] Electrolyte swelling resistance: The slurry was coated on the electrode, cured, and then immersed in electrolyte for 14 days. After drying at 120°C, the weight change was tested.

[0059] Adhesion performance: After the slurry is applied to the electrode and cured, the peel strength is measured in N / m.

[0060] Capacity retention: Capacity retention of the cell after 50 cycles of 1C / 1C charge / discharge at 25±2℃.

[0061] Heating: Charge the test cell to 100% SOC at 1C, then heat it from room temperature to 150℃ at a heating rate of 5℃ / min, hold it at that temperature for 30min, then continue to heat it at 5℃ / min, and hold it at that temperature for 30min every 5℃ increase, until the test object experiences thermal runaway. The temperature of the previous stage of thermal runaway is taken as the heating temperature.

[0062] Example 1

[0063] Take a 5000ml four-necked flask, reflux it under nitrogen protection, add 3000g N-methylpyrrolidone and 750g ESBR1500 to the reactor, stir and heat to 80℃ to dissolve the rubber for 2 hours to obtain a homogeneous rubber solution, add a mixture of 3.75g azobisisobutyronitrile and 7.5g diethyl vinylphosphonate dropwise, and complete the addition in 3 hours. After the addition is completed, keep the reaction at 80℃ for 2 hours to obtain a phosphorus-modified styrene-butadiene rubber polymer with a number average molecular weight of 65402.

[0064] The phosphorus-modified styrene-butadiene rubber polymer prepared in this embodiment has the following structural formula:

[0065]

[0066] H 1NMR (300MHZ, DMSO-D6) δ1.25-1.3 (540H, m), 1.44-1.62 (712H, m), 1.77-1.8 (36H, m), 1.96-2.0 (1292H, m), 2.16-2 .18(186H,m), 4.18-4.19(72H,m), 5.02-5.07(360H,m), 5.42-5.48(652H,m), 5.7(180H,m), 7.27-7.37(1660H,m).

[0067] Example 2

[0068] Take a 5000ml four-necked flask, reflux it under nitrogen protection, add 3000g N,N-dimethylformamide and 1000g SBS1401 to the reactor, stir and heat to 100℃ to dissolve the rubber for 8 hours to obtain a homogeneous solution, add a mixture of 25g benzoyl peroxide and 100g vinylphosphonic acid dropwise, and complete the addition in 4 hours. After the addition is completed, keep it at 100℃ for 2 hours to obtain a modified styrene-butadiene rubber polymer with a number average molecular weight of 100828.

[0069] The phosphorus-modified styrene-butadiene rubber polymer prepared in this embodiment has the following structural formula:

[0070]

[0071] H 1 NMR (300MHZ, DMSO-D6) δ1.25-1.3 (1026H, m), 1.44-1.62 (1263H, m), 1.77-1.8 (148H, m), 1.96-2.0 (1892H, m), 2.16 -2.18(199H,m), 5.02-5.07(250H,m), 5.42-5.48(1020H,m), 5.7(125H,m), 7.27-7.37(2060H,m), 11.98(342H,m).

[0072] Example 3

[0073] Take a 5000ml four-necked flask, reflux it under nitrogen protection, add 3000g ethyl acetate and 158g SSBR 2003 to the reactor, stir and heat to 90℃ to dissolve the rubber for 4 hours to obtain a homogeneous solution, add a mixture of 7.9g dodecyl peroxide and 7.9g vinyl phosphoric acid dropwise, and complete the addition in 1 hour. After the addition is complete, keep it at 90℃ for 1 hour to obtain a modified styrene-butadiene rubber polymer with a number average molecular weight of 81016.

[0074] The phosphorus-modified styrene-butadiene rubber polymer prepared in this embodiment has the following structural formula:

[0075]

[0076] H 1 NMR (300MHZ, DMSO-D6) δ1.25-1.3 (640H, m), 1.44-1.62 (899H, m), 1.77-1.8 (44H, m), 1.96-2.0 (1908H, m), 2.16- 2.18(162H,m), 5.02-5.07(280H,m), 5.42-5.48(976H,m), 5.7(140H,m), 7.27-7.37(1800H,m), 11.98(134H,m).

[0077] Example 4

[0078] Take a 5000ml four-necked flask, reflux it under nitrogen protection, and add 3000g of N-methylpyrrolidone and 530g of ESBR1500 to the reactor. Stir and heat to 85℃ to dissolve the rubber for 6 hours to obtain a homogeneous solution. Add a mixture of 7.95g of azobisisobutyronitrile and 10.6g of dimethyl vinyl phosphate dropwise over 2 hours. After the addition is complete, keep the temperature at 85℃ for 2 hours to obtain a modified styrene-butadiene rubber polymer with a number average molecular weight of 68108.

[0079] The phosphorus-modified styrene-butadiene rubber polymer prepared in this embodiment has the following structural formula:

[0080]

[0081] H 1 NMR (300MHZ, DMSO-D6) δ1.25-1.3 (492H, m), 1.44-1.62 (769H, m), 1.77-1.8 (80H, m), 1.96-2.0 (1270H, m), 2.16 -2.18(186H,m), 3.66(240H,m), 5.02-5.07(342H,m), 5.42-5.48(650H,m), 5.7(171H,m), 7.27-7.37(1660H,m).

[0082] Example 5

[0083] Take a 5000ml four-necked flask, reflux it under nitrogen protection, and add 3000g of N-methylpyrrolidone and 1285g of ESBR1500 to the reactor. Stir and heat to 95℃ to dissolve the rubber for 7 hours to obtain a homogeneous solution. Add a mixture of 10.28g of benzoyl peroxide and 38.55g of dimethyl vinyl phosphate dropwise over 2.5 hours. After the addition is complete, keep the solution at 95℃ for 2 hours to obtain a modified styrene-butadiene rubber polymer with a number average molecular weight of 69988.

[0084] The phosphorus-modified styrene-butadiene rubber polymer prepared in this embodiment has the following structural formula:

[0085]

[0086] H 1 NMR (300MHZ, DMSO-D6) δ1.25-1.3 (540H, m), 1.44-1.62 (809H, m), 1.77-1.8 (110H, m), 1.96-2.0 (1232H, m), 2.16 -2.18(185H,m), 3.66(330H,m), 5.02-5.07(330H,m), 5.42-5.48(636H,m), 5.7(165H,m), 7.27-7.37(1660H,m).

[0087] Application Example 1

[0088] Using the phosphorus-modified styrene-butadiene rubber polymer synthesized in Example 1 above as one of the main formulation agents for battery cell materials, the battery cell materials were prepared according to the following steps:

[0089] Graphite, silicon suboxide, conductive carbon black, carbon nanotubes, phosphorus-modified styrene-butadiene rubber polymer, and sodium carboxymethyl cellulose were mixed in a mass ratio of 84:12:1:0.5:1.5:1, and deionized water was added to homogenize the mixture. The mixture was then uniformly coated on both sides of a copper foil surface. After drying, rolling, and die-cutting, a negative electrode sheet (sample A1) was obtained.

[0090] The tensile properties and swelling resistance of the prepared sample A1 were tested, and it was used in the battery to test the battery cycle performance and safety performance such as heating and nail penetration. The test results are shown in Table 1.

[0091] Application Example 2-5

[0092] Negative electrode sheets were prepared according to the method in Application Example 1, with the only difference being that the phosphorus-modified styrene-butadiene rubber polymer used was replaced with the product in Examples 2-5. The resulting negative electrode sheets were numbered A2-A5. Performance tests were also performed, and the results are shown in Table 1.

[0093] Comparative Example 1

[0094] Vinyl phosphate self-polymer was prepared using diethyl vinyl phosphonate as a raw material, and then mixed with styrene-butadiene rubber ESBR 1500. The mixing mass ratio was the same as that of ESBR 1500 to diethyl vinyl phosphonate in Example 1, to obtain a styrene-butadiene rubber composition.

[0095] Comparative Example 2

[0096] The modified styrene-butadiene rubber polymer was prepared by referring to the preparation method in Example 1, except that the raw material diethyl vinylphosphonate was replaced with triethyl phosphate, while other operations and conditions remained unchanged.

[0097] Comparative Application Example 1

[0098] Negative electrode sheets D1 and D2 were prepared according to the method in Application Example 1, with the only difference being that the phosphorus-modified styrene-butadiene rubber polymer was replaced with the composition of styrene-butadiene rubber and vinyl phosphate self-polymer in Comparative Example 1 and the modified styrene-butadiene rubber polymer prepared in Comparative Example 2. Performance tests were performed, and the results are shown in Table 1.

[0099] Table 1 Performance Test Results

[0100]

[0101]

[0102] As can be seen from the data in Table 1, the phosphorus-modified styrene-butadiene rubber polymer product prepared by this invention can effectively enhance the resistance to electrolyte swelling, flame retardancy, and adhesion performance when used as a battery negative electrode adhesive, thereby improving the safety performance of the battery.

[0103] The above description is only a preferred embodiment of the present invention. It should be noted that those skilled in the art can make several improvements and additions without departing from the method of the present invention, and these improvements and additions should also be considered within the scope of protection of the present invention.

Claims

1. A phosphorus-modified styrene-butadiene rubber polymer, characterized in that, It has the structure shown in Equation 1: （1） In the formula, R1 and R2 are each independently selected from H and C1-12 alkyl groups; R1 and R2 may be the same or different; x is an integer ≥ 1, y is an integer ≥ 1, z is an integer ≥ 1, m is an integer ≥ 1, and n is an integer ≥ 1.

2. The phosphorus-modified styrene-butadiene rubber polymer according to claim 1, characterized in that, x is an integer between 10 and 500, y is an integer between 10 and 500, z is an integer between 10 and 500, m is an integer between 10 and 100, and n is an integer between 10 and 100.

3. The phosphorus-modified styrene-butadiene rubber polymer according to claim 1, characterized in that, The number average molecular weight is 5w-100w.

4. A method for preparing the phosphorus-modified styrene-butadiene rubber polymer according to any one of claims 1-3, characterized in that the step... include: S1: Add styrene-butadiene rubber polymer to a solvent, heat and stir to dissolve to obtain a rubber solution; S2: Add vinyl phosphate monomers and initiators to the adhesive solution in step S1 to carry out a free radical grafting reaction to obtain the phosphorus-modified styrene-butadiene rubber polymer.

5. The preparation method according to claim 4, characterized in that, The styrene-butadiene rubber polymer described in step S1 has the structure shown in Formula 2: （2） In the formula, the values ​​of x, y, and z are the same as in Formula 1.

6. The preparation method according to claim 4, characterized in that, The rubber polymer mentioned in step S1 is one or more of solution-polymerized styrene-butadiene rubber, emulsion-polymerized styrene-butadiene rubber, and styrene-butadiene block copolymer.

7. The preparation method according to claim 4, characterized in that, The solvent in step S1 is one or more of N,N-dimethylformamide, N,N-dimethylacetamide, ethyl acetate, dimethyl sulfoxide, and N-methylpyrrolidone; and / or The content of the styrene-butadiene rubber polymer in the adhesive solution in step S1 is 5-30 wt%.

8. The preparation method according to claim 4, characterized in that, The dissolution process described in step S1 is carried out at a temperature of 80-100℃ for 2-8 hours.

9. The preparation method according to claim 4, characterized in that, The vinyl phosphate monomers described in step S2 have the structure shown in Formula 3: （3） In the formula, R1 and R2 are the same as in Formula 1.

10. The preparation method according to claim 4, characterized in that, The vinyl phosphate monomers mentioned in step S2 are vinyl monomers with phosphonate groups; and / or The mass ratio of the vinyl phosphate monomer in step S2 to the styrene-butadiene rubber polymer in step S1 is (1-10):

100.

11. The preparation method according to claim 10, characterized in that, The vinyl phosphate monomers are one or more of dibutyl vinylphosphonate, dipropyl vinylphosphonate, diethyl vinylphosphonate, dimethyl vinylphosphonate, and vinylphosphonic acid.

12. The preparation method according to claim 4, characterized in that, The initiator mentioned in step S2 is one or more of azo initiators, peroxide initiators, and cationic / anionic initiators; and / or The amount of initiator used in step S2 is 0.5-5% of the mass of the styrene-butadiene rubber polymer in step S1.

13. The preparation method according to claim 12, characterized in that, The initiator is selected from one or more of azobisisobutyronitrile, azobisisoheptanenitrile, azobis(dimethyl)valerate, cumene hydroperoxide, tert-butyl hydroperoxide, p-menthol hydroperoxide, potassium persulfate, ammonium persulfate, lauroyl peroxide, benzoyl peroxide, and dodecyl peroxide.

14. The preparation method according to claim 4, characterized in that, The free radical grafting reaction described in step S2 is carried out under an inert protective atmosphere; and / or The free radical grafting reaction described in step S2 is carried out at a temperature of 80-100℃ for 2-6 hours; and / or In step S2, the vinyl phosphate monomers and the initiator are added by dropping, with a dropping time of 1-4 hours. The dropping time is not included in the aforementioned reaction time. After the dropping is completed, the reaction is kept at a constant temperature.

15. The preparation method according to claim 14, characterized in that, The inert protective atmosphere is nitrogen, argon, or helium.

16. The application of the phosphorus-modified styrene-butadiene rubber polymer according to any one of claims 1-3, or the phosphorus-modified styrene-butadiene rubber polymer prepared by the method according to any one of claims 4-15, in the field of battery adhesives.

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