Study On Preparation Process And Mechanism Of High Comprehensive Performance Rubber Sealing Plate

Our country’s graphite resources are very rich,and the flexible graphite prepared by it has wide application and development prospects as engineering materials.Flexible graphite is widely used in the sealing industry because of its excellent performance.It is known as the“King of Seals”,but the flexible graphite sealing plates made of flexible graphite alone rely on mechanical biting force and have low strength.Shortcomings such as easy breakage and low processing yield are limited in practical applications.Therefore,this paper makes use of flexible graphite and aramid fiber,softwood fiber,sepiolite fiber and other components to make flexible graphite composite sealing material,improve the defects of pure flexible graphite products,improve the performance of sealing materials.Research indicates:The expansion volume of flexible graphite increases with increasing temperature.The temperature is too high and the expansion volume decreases.The expansion volume is only 100ml/g at 500°C,the expansion volume is 344ml/g at 800°C,and the expansion volume is 407ml/g at 1000°C.At 1100°C,the expansion volume is reduced due to ablation.When the temperature increases,the yield gradually decreases.When the temperature is 1100°C,the yield is 73.5%,which is no longer lost.When the amount of aluminum sulfate is 6%,the maximum beating degree is27.0~°SR,and the retention rate is up to 94.45%.The drainage performance is good and the pH is about 7.02.The expansion temperature of flexible graphite has a great influence on the tensile strength,compressibility and rebound rate of the rubber-sealed plate.The comprehensive performance is best when the expansion temperature is 800°C.At this time,the tensile strength is 10.82 MPa and the compression ratio is 15.21%,the rebound rate was 24.41%.The flexible graphite prepared at 800°C expansion temperature was selected.With the increase of the amount of flexible graphite,the tensile strength,compressibility and rebound rate of the rubber-sealed plate were increased to different degrees.The amount of flexible graphite was 40%.When the comprehensive performance is the best,the tensile strength is 13.03 MPa,the compression ratio is 17.17%,and the rebound rate is 34.46%.The improved Hummers method oxidizes flexible graphite,increases the number of oxygen-containing functional groups on the surface,and improves its dispersibility in water.However,its structural damage to flexible graphite is more serious.Moderate oxidation modification of flexible graphite.When the process conditions are:mass ratio of potassium permanganate to flexible graphite is 2:1,reaction time is4h,reaction temperature is 50°C,the composite rubber seal plate prepared at this time The tensile strength and compression ratio and rebound rate are the best,the tensile strength is 14.18 MPa,the rebound rate is 41.15%,and the compression ratio is11.96%.The analysis of oxidized flexible graphite under this condition showed that the oxygen-containing functional groups on the surface of the flexible graphite increased,and the mixed slurry was uniformly mixed,completely precipitated,and the microstructure was not destroyed to a large extent.The original porous structure of the flexible graphite was well obtained.Reserved.Adding moderately oxidized flexible graphite to the mixed slurry to make a plate,the tensile strength and rebound rate increase significantly with the increase of the amount of flexible graphite,and the compression rate decreases rapidly and then slows down.When%,the tensile strength was 14.87 MPa,the rebound rate was45.28%,and the compression ratio was 10.65%.