A method for producing a synthetic polyisoprene latex, including a step of mixing a latex of synthetic polyisoprene (A) synthesized by use of a Ziegler type catalyst and a latex of synthetic polyisoprene (B) synthesized by use of an organic alkali metal catalyst at a weight ratio of “synthetic polyisoprene (A): synthetic polyisoprene (B)=10:90 to 90:10”. In the method, preferably, the weight average molecular weight of the synthetic polyisoprene (A) is 100,000 to 3,000,000 and the weight average molecular weight of the synthetic polyisoprene (B) is 1,000,000 to 5,000,000.

A method for producing a synthetic polyisoprene latex, including a step of mixing a latex of synthetic polyisoprene (A) synthesized by use of a Ziegler type catalyst and a latex of synthetic polyisoprene (B) synthesized by use of an organic alkali metal catalyst at a weight ratio of “synthetic polyisoprene (A): synthetic polyisoprene (B)=10:90 to 90:10”. In the method, preferably, the weight average molecular weight of the synthetic polyisoprene (A) is 100,000 to 3,000,000 and the weight average molecular weight of the synthetic polyisoprene (B) is 1,000,000 to 5,000,000.

The present invention relates to a diene-based rubber latex including a polymer aggregate and having an extra large diameter, a method for preparing same and a graft copolymer with a core-shell structure, including same and having excellent impact strength and surface properties. A diene-based rubber latex of which 14 wt % to 26 wt % has diameter of 100 nm to less than 300 nm, 62 wt % to 81 wt % has a diameter of 300 nm to less than 800 nm, and 5 wt % to 14 wt % has a diameter of 800 nm to less than 1000 nm, based on 100 wt % of total rubber particles.

A curable resin composition for producing a three-dimensional object formed of a cured resin product comprises a polyfunctional urethane (meth)acrylate having a weight-average molecular weight of 1,000 or more and 60,000 or less; a monofunctional radically polymerizable compound having one radically polymerizable functional group in a molecule; a polyfunctional radically polymerizable compound other than the polyfunctional urethane (meth)acrylate; rubber particles; and a radical polymerization initiator. The monofunctional radically polymerizable compound includes a monofunctional acrylamide-based compound, and the content of the polyfunctional radically polymerizable compound other than polyfunctional urethane (meth)acrylate (particularly one having a radically polymerizable functional group equivalent of less than 300 g/eq) is controlled.

A high performing low viscosity tire sealant includes about 15% to about 75% by weight of a biobased aliphatic diol, about 5% to about 50% by weight natural rubber latex, and about 2% to about 50% by weight synthetic rubber latex. The tire sealant exhibits excellent performance at temperatures of −40 degrees Celsius and lower.

A curable resin composition for producing a three-dimensional object formed of a cured resin product comprises a polyfunctional urethane (meth)acrylate having a weight-average molecular weight of 1,000 or more and 60,000 or less; a monofunctional radically polymerizable compound having one radically polymerizable functional group in a molecule; a polyfunctional radically polymerizable compound other than the polyfunctional urethane (meth)acrylate; rubber particles; and a radical polymerization initiator. The monofunctional radically polymerizable compound includes a monofunctional acrylamide-based compound, and the content of the polyfunctional radically polymerizable compound other than polyfunctional urethane (meth)acrylate (particularly one having a radically polymerizable functional group equivalent of less than 300 g/eq) is controlled.

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.

Methods to prepare elastomer compounds are described that include dry mixing at least one additive to an elastomer composite masterbatch at low temperatures over a shortened mixing cycle with reduced energy consumption. The elastomer composite masterbatch is produced in a liquid masterbatch process. The resulting elastomer compounds are further described as well as property improvements that can be achieved.

Methods to prepare elastomer compounds are described that include dry mixing at least one additive to an elastomer composite masterbatch at low temperatures over a shortened mixing cycle with reduced energy consumption. The elastomer composite masterbatch is produced in a liquid masterbatch process. The resulting elastomer compounds are further described as well as property improvements that can be achieved.

The present disclosure provides compositions and products formed therefrom. In particular, the disclosure provides elastomeric latex articles, such as gloves and condoms, that can exhibit a desired combination of properties that can be correlated to suitable strength and softness.