RUBBER MIXTURE Russian patent published in 2019 - IPC C08L9/02 C08L31/04 E21B33/12 C09K3/10 C08K3/11 C08K3/13 C08K3/14 C08K3/22 C08K3/28 C08K5/09 C08K5/40 

FIELD: technological processes.

SUBSTANCE: invention relates to rubber industry and can be used for inner layer of sealing elements in water-swellable packers used in oil and gas industry. Rubber mixture contains the following components, pts.wt.: butadiene-nitrile rubber with nitrile of acrylic acid content of 17–20 % (10.0–16.0), butadiene-methylstyrene rubber SKMS-30ARK (38.0–50.0), ethylene-propylene rubber SKEPT-40 (40.0–46.0), sevylene 11808-340 (24.0–26.0), sulfur (1.5–2.5), 2,2'-dibenzothiazol disulfide (1.5–2.0), guanide F (0.5–1.2), zinc white (2.5–3.5), stearic acid (1.0–2.0), acetone anil H (0.5–1.0), technical carbon P 514 (9.5–10.5), rosil 175 (9.5–10.5), talc (9.5–10.5), finely ground mineral powder of schungite (9.5–10.5), colophony (4.5–5.5), polyacrylamide AK 639 (45.0–50.0), sodium polyacrylate (60.0–65.0) and "Cometa-R" reagent (4.5–5.5).

EFFECT: improved index of relative elongation at break of rubber and increased degree of its volumetric swelling in water.

1 cl, 2 tbl