RUBBER MIXTURE Russian patent published in 1997 - IPC

FIELD: rubber industry. SUBSTANCE: invention proposes rubber mixture based on high-molecular and low-molecular copolymers of vinylidene-fluoride and hexafluoropropylene at ratio of monomeric links = 3:1. Rubber mixture has, mas. p. p.: high-molecular copolymer of vinylidene-fluoride with hexafluoropropylene 80-90; low-molecular copolymer of vinylidene-fluoride with hexafluoropropylene - block-copolymer with part of successively bound links of vinylidene-fluoride ≥ 3 - 40-45 mole%, viscosity is 20-25 U at 100 C and 10-15 U at 121 C, ratio of pliability at 75 C and 50 C - 3.07-3.09, intrinsic relaxation time at 25 C - 1400-1800 s 10-20; carbon or mineral filling agent 15-40; bis-phenol 0.8-5; bivalent metal oxide 2-5; calcium hydroxide 4-8; quaternary ammonium or phosphonium salt 0.2-0.8; wax or low-molecular polyethylene 0.5-5; Rubber properties: after ageing at 200 C for 24 h: conventional tensile strength is 109-168 kgf/sm², relative elongation at rupture is 180-230%, relative residual compression deformation at 200 C for 24 h is 2-35%. Rubber mixture is used for rubber technical article making working in corrosive media at increased temperatures. EFFECT: improved quality of mixture. 4 tbl