A synthetic polyisoprene latex containing synthetic polyisoprene, wherein the synthetic polyisoprene constituting the synthetic polyisoprene latex includes a low-molecular weight synthetic isoprene chain having a molecular weight of less than 1,000,000 at a content rate of 10 to 70% by weight and a high-molecular weight synthetic isoprene chain having a molecular weight of 1,000,000 or more at a content rate of 30 to 90% by weight. Also, a method for producing the synthetic polyisoprene latex, wherein the synthetic polyisoprene containing the low-molecular weight synthetic isoprene chain and the high-molecular weight synthetic isoprene chain is obtained by polymerizing a monomer containing isoprene in an organic solvent by use of an organic alkali metal catalyst.

A method for producing a polymer containing metal atoms or halogen atoms at the terminals thereof with excellent efficiency while minimizing or eliminating side reactions or the like is provided. The method can also freely control molecular weight characteristics of the polymer.

Metallated aminosilane compounds for use as functional initiators in anionic polymerizations and processes for producing an aminosilane-functionalized polymer using the metallated aminosilane compounds to initiate anionic polymerization of at least one type of anionically polymerizable monomer. Preferred use of the metallated aminosilane compounds results in rubber compositions for use in tires comprising an aminosilane functionalized polymer.

Metallated aminosilane compounds for use as functional initiators in anionic polymerizations and processes for producing an aminosilane-functionalized polymer using the metallated aminosilane compounds to initiate anionic polymerization of at least one type of anionically polymerizable monomer. Preferred use of the metallated aminosilane compounds results in rubber compositions for use in tires comprising an aminosilane functionalized polymer.

This invention relates to processes for forming hydrogen mediated saline hydride initiated anionic polystyrene distributions via novel polymerization conditions. This invention also relates to novel hydrocarbon soluble super active saline hydride catalyst and reagent compositions useful in conducting the hydrogen mediated saline hydride initiated polymerizations of this invention. This invention also relates to novel low molecular weight polystyrene polymer composition formed exclusively from styrene and molecular hydrogen as the monomers.

This invention relates to processes for forming hydrogen mediated saline hydride initiated anionic polystyrene distributions via novel polymerization conditions. This invention also relates to novel hydrocarbon soluble super active saline hydride catalyst and reagent compositions useful in conducting the hydrogen mediated saline hydride initiated polymerizations of this invention. This invention also relates to novel low molecular weight polystyrene polymer composition formed exclusively from styrene and molecular hydrogen as the monomers.

This invention relates to processes for forming hydrogen mediated saline hydride initiated anionic polystyrene distributions via novel polymerization conditions. This invention also relates to novel hydrocarbon soluble super active saline hydride catalyst and reagent compositions useful in conducting the hydrogen mediated saline hydride initiated polymerizations of this invention. This invention also relates to novel low molecular weight polystyrene polymer composition formed exclusively from styrene and molecular hydrogen as the monomers.