Method for preparing rubber for elastomer of flexible joint

A method for preparing a rubber for an elastomer of a flexible joint, the method comprising:

• 1) weighing 100 parts by weight of hydrogenated nitrile raw rubber, 15-35 parts by weight of a silica reinforcing agent, 10-25 parts by weight of aramid fiber pulp, 30-50 parts by weight of carbon black, 5-15 parts by weight of liquid nitrile rubber, 3-7 parts by weight of zinc oxide, 0.5-3 parts by weight of stearic acid, 0.5-5 parts by weight of an antioxidant, and 2-8 parts by weight of di-tert-butylperoxyisopropyl benzene as a peroxide crosslinking agent;
• 2) plasticating the hydrogenated nitrile raw rubber in a first internal mixer at 125-135° C., collecting a resulting product and cooling, to yield a plasticized rubber;
• 3) preheating the liquid nitrile rubber at a temperature of 80-85° C.;
• 4) adding the plasticized rubber to a second internal mixer, further adding the aramid fiber pulp, the zinc oxide, the stearic acid, and the antioxidant to the second internal mixer for first mixing;
• adding the carbon black to the second internal mixer for second mixing;
• adding the silica reinforcing agent and the preheated liquid nitrile rubber to the second internal mixer for third mixing;
• collecting a discharged product when a temperature of the second internal mixer is 140° C.;
• 5) adding the discharged product to an open mill, further adding di-tert-butylperoxyisopropyl benzene to the open mill, and passing a resulting mixture through rollers of the open mill for 5-7 times at 45-55° C., to yield a rubber for an elastomer of a flexible joint.