Lithium battery electrolyte solution resistant fluororubber composition and preparation method thereof

[0025] Example 1-8

[0026] The fluororubber A and tetrapropylene fluororubber or fluororubber B in Table 1 are uniformly masticated on a two-roll mill and covered with rolls, and then crosslinking agent DBPH50, auxiliary crosslinking agent TAIC S70, carbon black N990 and processing aid All auxiliary materials such as agent HT290 are pre-mixed uniformly, and slowly added to the open mill. After all the powdery auxiliary materials are eaten, the roll rubber material is opened 5 times, and then the triangle bag 10 times, so that the rubber and auxiliary materials are fully mixed Then, adjust the roller pitch to discharge the sheet, and control the thickness to 6mm to obtain a fluororubber composition compound that is resistant to lithium battery electrolyte. The entire mixing process is controlled within 10 minutes, and the roll temperature of the open mill is controlled within 80°C. After the prepared rubber compound is aged for 16 hours, it is then re-mixed to produce tablets; the prepared rubber compound is subjected to a second-stage vulcanization for 8 hours at a molding temperature of 180°C, a clamping pressure of 20 MPa, and a molding time of 10 minutes. At 230°C, a rubber test piece of length 180 mm × width 180 mm × thickness 2 mm was prepared by moulding. The rubber test piece was prepared according to the standard test sample and tested for physical and mechanical properties, as well as resistance to lithium battery electrolyte performance and changes , The test conditions and results are shown in Table 1.

[0027] Table 1 Performance test of seals prepared from fluororubber composition resistant to lithium battery electrolyte

[0028]

[0029] The data in Table 1 shows that the physical and mechanical properties of the composition of Example 1 and the changes in the electrolyte solvent can be seen. The Viton GF600S composition material of fluoroelastomer is completely immersed in the electrolyte solvent, no matter at room temperature or at 40℃. , After 168 hours, the volume change has been greater than 30%, and the physical and mechanical properties, tensile strength and elongation at break, have changed more than 50%. From the perspective of seal design, it is no longer suitable for sealing applications under this working condition.

[0030] The physical and mechanical properties of the composition of Example 2 and the changes in the electrolyte solvent can be seen, and the composition material after using 10 parts of alkali-resistant fluororubber Viton ETP600S is completely immersed in the electrolyte solvent, and heated at room temperature and 40°C. Under the conditions, after 168 hours, the volume change has been reduced, its chemical resistance performance has been improved, and the physical properties and mechanical properties, tensile strength and elongation at break have also been reduced. It can be seen that the combined use of alkali-resistant fluororubber Viton ETP600S can be improved Viton GF600S is resistant to electrolyte and solvent.

[0031] The physical and mechanical properties of the compositions of Examples 3 and 4 and the changes in the electrolyte solvent can be seen. The composition of Viton GF200S with alkali-resistant fluororubber Viton ETP600S and micronized polytetrafluoroethylene Zonyl MP1400 is completely After immersing in the electrolyte solvent, at room temperature and heating at 40°C, the volume change is further improved to within 30% after 168 hours, which greatly improves the chemical resistance of the rubber compound and improves the physical and mechanical properties. The change in tensile strength and elongation at break is further reduced to less than 50%, and its compression set rate is also in the range of 35%. It can be seen that the composition of Examples 3 and 4 greatly improves the electrolyte resistance of Viton GF600S. Solvent performance, from the perspective of sealing design, the composition of Examples 3 and 4 can be applied to static sealing conditions under the requirements of the sealing application of the electrolyte and solvent conditions. At the same time, the fluororubber materials used in Examples 3 and 4 have high temperature resistance. It has better performance and solves the technical problem that EPDM rubber is not heat-resistant in the prior art.

[0032] The physical and mechanical properties of the compositions of Examples 5 and 6 and the changes in the electrolyte solvent can be seen. The fluororubber Viton GF200S is used in combination with tetrapropylene fluororubber Aflas X600 and polytetrafluoroethylene powder Zonyl MP1400. The composition material is completely immersed in the electrolysis In a liquid solvent, at room temperature and a temperature of 40°C, after 168 hours, the volume change is further improved to within 30%, and the physical and mechanical properties, tensile strength and elongation at break, are further reduced to within 50%, making the rubber compound The chemical resistance of the material has been greatly improved, and its compression set rate is also in the range of 35%. It can be seen that the compositions of Examples 5 and 6 are considered from the perspective of sealing design, and the sealing application of the electrolyte solvent condition Upon request, the compositions of Examples 5 and 6 can meet the conditions of static sealing conditions. At the same time, the fluororubber materials used in Examples 5 and 6 have better high temperature resistance performance, which solves the problem of EPDM in the prior art. Thermal technical issues.

[0033] The physical and mechanical properties of the composition of Example 7 and the changes in the electrolyte solvent can be seen, 100 parts of the tetrapropylene fluororubber Aflas X600 composition material is completely immersed in the electrolyte solvent, at room temperature and at a temperature of 40°C, After 168 hours, the volume change is about 20%, but the tensile strength change of physical properties and mechanical properties is greater than 50%, and the hardness change is also large. Its compression set rate is 40%. From the perspective of seal design, it is no longer suitable for this working condition. Under seal application requirements.