The present invention relates to a process for obtaining aging-resistant natural rubber, to a rubber composition comprising the thus-obtained natural rubber and to the use of this composition for producing consumer goods.

The present invention relates to a process for obtaining aging-resistant natural rubber, to a rubber composition comprising the thus-obtained natural rubber and to the use of this composition for producing consumer goods.

The present invention relates to a solidification process of the natural rubber latex by means of polyquaternary polymers. The process of the present invention has the advantage to not require the addition of acids and/or salts, with an evident saving in terms of cost for the reagents. Furthermore, in such a way neither the neutralization step of the rubber nor the treatment of the processing water before their disposal are required. The process of the present invention is suitable both for the continuous and batchwise embodiment, with evident advantages as far as its industrial application is concerned.

The present invention relates to a solidification process of the natural rubber latex by means of polyquaternary polymers. The process of the present invention has the advantage to not require the addition of acids and/or salts, with an evident saving in terms of cost for the reagents. Furthermore, in such a way neither the neutralization step of the rubber nor the treatment of the processing water before their disposal are required. The process of the present invention is suitable both for the continuous and batchwise embodiment, with evident advantages as far as its industrial application is concerned.

A method produces a hydrogenated nitrile rubber having an iodine value of 120 or less, the method having a first coagulation step of adding a halogen atom-free metal salt as a coagulant to a nitrile rubber latex to form a nitrile rubber coagulum; a solution preparation step of dissolving the nitrile rubber coagulum in an organic solvent to prepare a nitrile rubber solution; a hydrogenation step of subjecting the nitrile rubber solution to a hydrogenation reaction to afford a hydrogenated nitrile rubber solution; and a second coagulation step of adding a divalent metal salt as a coagulant to the hydrogenated nitrile rubber solution to form a hydrogenated nitrile rubber coagulum.

A method produces a hydrogenated nitrile rubber having an iodine value of 120 or less, the method having a first coagulation step of adding a halogen atom-free metal salt as a coagulant to a nitrile rubber latex to form a nitrile rubber coagulum; a solution preparation step of dissolving the nitrile rubber coagulum in an organic solvent to prepare a nitrile rubber solution; a hydrogenation step of subjecting the nitrile rubber solution to a hydrogenation reaction to afford a hydrogenated nitrile rubber solution; and a second coagulation step of adding a divalent metal salt as a coagulant to the hydrogenated nitrile rubber solution to form a hydrogenated nitrile rubber coagulum.

A method for producing a polymer latex, including an emulsification step of mixing a polymer solution obtained by dissolution of synthetic polyisoprene and/or a styrene-isoprene-styrene block copolymer in an organic solvent, with an aqueous solution including 0.1 to 30 parts by weight of a rosinate based on 100 parts by weight in total of the synthetic polyisoprene and the styrene-isoprene-styrene block copolymer, and emulsifying the resultant in water to thereby obtain an emulsified liquid, a solvent removal step of removing the organic solvent in the emulsified liquid, and a concentration step of concentrating the emulsified liquid from which the organic solvent is removed, and also adjusting the content rate of the rosinate in the emulsified liquid after concentration, in the range of 0.1 to 3 parts by weight based on 100 parts by weight in total of the synthetic polyisoprene and the styrene-isoprene-styrene block copolymer in the emulsified liquid.

A method for producing a polymer latex, including an emulsification step of mixing a polymer solution obtained by dissolution of synthetic polyisoprene and/or a styrene-isoprene-styrene block copolymer in an organic solvent, with an aqueous solution including 0.1 to 30 parts by weight of a rosinate based on 100 parts by weight in total of the synthetic polyisoprene and the styrene-isoprene-styrene block copolymer, and emulsifying the resultant in water to thereby obtain an emulsified liquid, a solvent removal step of removing the organic solvent in the emulsified liquid, and a concentration step of concentrating the emulsified liquid from which the organic solvent is removed, and also adjusting the content rate of the rosinate in the emulsified liquid after concentration, in the range of 0.1 to 3 parts by weight based on 100 parts by weight in total of the synthetic polyisoprene and the styrene-isoprene-styrene block copolymer in the emulsified liquid.

A method produces a hydrogenated nitrile rubber having an iodine value of 120 or less, the method having a first coagulation step of adding a halogen atom-free metal salt as a coagulant to a nitrile rubber latex to form a nitrile rubber coagulum; a solution preparation step of dissolving the nitrile rubber coagulum in an organic solvent to prepare a nitrile rubber solution; a hydrogenation step of subjecting the nitrile rubber solution to a hydrogenation reaction to afford a hydrogenated nitrile rubber solution; and a second coagulation step of adding a divalent metal salt as a coagulant to the hydrogenated nitrile rubber solution to form a hydrogenated nitrile rubber coagulum.

A method produces a hydrogenated nitrile rubber having an iodine value of 120 or less, the method having a first coagulation step of adding a halogen atom-free metal salt as a coagulant to a nitrile rubber latex to form a nitrile rubber coagulum; a solution preparation step of dissolving the nitrile rubber coagulum in an organic solvent to prepare a nitrile rubber solution; a hydrogenation step of subjecting the nitrile rubber solution to a hydrogenation reaction to afford a hydrogenated nitrile rubber solution; and a second coagulation step of adding a divalent metal salt as a coagulant to the hydrogenated nitrile rubber solution to form a hydrogenated nitrile rubber coagulum.