RUBBER MIX Russian patent published in 1995 - IPC

FIELD: production of rubber mix. SUBSTANCE: rubber mix contains mas. part: butadiene-nitrile rubber with 26-34 mas.% of nitrile units of acrylic acid or tri-ethylene-propylenediene rubber 100; filler 50-70; vulcanization accelerator 1.5-4.5; sulfur 1-2; activator of vulcanization 5-10; antiager 1-2; softener 15-30; antiscorcher 0.3-0.5; organosilicon oligoisocyanate 0.25-6.0. Organosilicon oligoisocyanate is introduced into rubber mix at the stage of mixing in form of 70 mas.% of solution in toluene or methyl ethyl ketone. Characteristic of rubber based on SKEPT-50: ultimate breaking strength 16-20 MPa, elongation 440-577%; coefficient of thermal aging (at 100 C x 72 h): rupture strength 0.98-1.2; elongation 0.73-1.04; coefficient of thermal aging (at 140 C x 72 h): rupture strength 0.96-1.15; elongation 0.51-0.63; abradability 205-271 cu.cm/kWh. EFFECT: higher efficiency. 5 tbl