Abstract: The residual hydrogenation catalyst from the hydrogenated nitrile rubber solution is recovered by using two steps such as (1) the catalyst extraction step with an ammonium salt and water (optionally including an oxidation step) to extract catalyst from the HNBR polymer chain to the solvent and then (2) the separation/column recovery step with the column packed with functional ion exchange resins for the separation of ammonia-catalyst complex from hydrogenated nitrile rubber solution and the column recovery for the high catalyst recovery with functional groups of resins. The ammonium salt for the catalyst extraction step is selected from ammonium chloride, ammonium bromide, ammonium iodide, and ammonium acetate. The functional groups in the functional ion exchange resins for packing the column is selected from thiourea, thiouronium, thiol, amine, diamine, triamine, TMT, dithiocarbamate, and carbodithioate.

Abstract: The residual hydrogenation catalyst from the hydrogenated nitrile rubber solution is recovered by using two steps such as (1) the catalyst extraction step with an ammonium salt and water (optionally including an oxidation step) to extract catalyst from the HNBR polymer chain to the solvent and then (2) the separation/column recovery step with the column packed with functional ion exchange resins for the separation of ammonia-catalyst complex from hydrogenated nitrile rubber solution and the column recovery for the high catalyst recovery with functional groups of resins. The ammonium salt for the catalyst extraction step is selected from ammonium chloride, ammonium bromide, ammonium iodide, and ammonium acetate. The functional groups in the functional ion exchange resins for packing the column is selected from thiourea, thiouronium, thiol, amine, diamine, triamine, TMT, dithiocarbamate, and carbodithioate.

Abstract: Residual hydrogenation catalyst produced from reduction of nitrile rubber is recovered by a chelation step using a chelating agent and a series of extraction using semi-coagulation with polar solvents and an optional washing steps for the separation of catalyst-chelating agent complex from hydrogenated nitrile rubber solution. The chelating agent is selected from xanthate, dithiocarbamate, and trithiocarbonate compounds.

Abstract: Residual hydrogenation catalyst produced from reduction of nitrile rubber is recovered by a chelation step using a chelating agent and a series of extraction using semi-coagulation with polar solvents and an optional washing steps for the separation of catalyst-chelating agent complex from hydrogenated nitrile rubber solution. The chelating agent is selected from xanthate, dithiocarbamate, and trithiocarbonate compounds.

Abstract: A water swellable rubber composition comprising (a) a non-water swellable base rubber, (b) an ethylene oxide based hydrophilic elastomer having from zero up to 20 mole % of a crosslinkable curable functional group, and (c) a water swellable non-elastomeric material. The composition has excellent water swell characteristics under prolonged exposure to high temperature and various electrolyte solutions and is suitable for oil field applications. When (b) has from zero to less than 5 mole % of crosslinkable functional group, the amount of (b) is between about 30 parts and 300 parts by weight based on 100 parts by weight of (a) and the amount of (c) is between about 20 parts and 200 parts by weight based on 100 parts by weight of (a), the composition is characterized by good shape retention after undergoing constrained swell, and a high degree of constrained swell at elevated temperatures in different saline concentrations.

Abstract: A water swellable rubber composition comprising (a) a non-water swellable base rubber, (b) an ethylene oxide based hydrophilic elastomer having from zero up to and including 20 mole % of a crosslinkable curable functional group, and (c) a water swellable non-elastomeric material. The composition has excellent water swell characteristics under prolonged exposure to high temperature and various electrolyte solutions (strongly saline as well as acid conditions) and is particularly suitable for oil field applications.

Abstract: Coalesced rubber particles having an average particle size of 5-50 microns are produced by: (1) adding simultaneously to a latex of pre-crosslinked rubber particles a solvent and an electrolyte solution to form swollen rubber aggregation particles, wherein the solvent has a lower boiling point than water and a capacity of swelling the rubber by at least 10 wt %, and the electrolyte is a solution of at least one metal salt; (2) removing the solvent under atmospheric pressure or low vacuum and at temperature greater than 80° C. to coalesce the rubber into particles having an average particle size of 5-50 50 microns; (3) filtering and washing with methanol; and (4) filtering the washed particles to remove methanol. An epoxy resin is blended with the particles and residual methanol removed, to obtain a blend containing coalesced rubber particles having an average particle size of 5-50 microns in the blended state.

Abstract: Coalesced rubber particles having an average particle size of 5-50 microns are produced by: (1) adding simultaneously to a latex of pre-crosslinked rubber particles a solvent and an electrolyte solution to form swollen rubber aggregation particles, wherein the solvent has a lower boiling point than water and a capacity of swelling the rubber by at least 10 wt %, and the electrolyte is a solution of at least one metal salt; (2) removing the solvent under atmospheric pressure or low vacuum and at temperature greater than 80° C. to coalesce the rubber into particles having an average particle size of 5-50 50 microns; (3) filtering and washing with methanol; and (4) filtering the washed particles to remove methanol. An epoxy resin is blended with the particles and residual methanol removed, to obtain a blend containing coalesced rubber particles having an average particle size of 5-50 microns in the blended state.

Abstract: A water swellable rubber composition comprising (a) a non-water swellable base rubber, (b) an ethylene oxide based hydrophilic elastomer having from zero up to and including 20 mole % of a crosslinkable curable functional group, and (c) a water swellable non-elastomeric material. The composition has excellent water swell characteristics under prolonged exposure to high temperature and various electrolyte solutions (strongly saline as well as acid conditions) and is particularly suitable for oil field applications.

Abstract: A water swellable rubber composition comprising (a) a non-water swellable base rubber, (b) a crosslinkable ethylene oxide based hydrophilic elastomer having at least one curable functional group, and (c) a water swellable non-elastomeric material. The composition has excellent water swell characteristics under prolonged exposure to high temperature and various electrolyte solutions (strong salinity as well as acid conditions) and is particularly suitable for oil field applications.