The present disclosure is directed towards a solution or bulk polymerization process for preparing high-cis polydienes that utilizes at least one vinyl aromatic compound as a molecular weight regulator. The disclosed solution or bulk polymerization processes are useful for preparing high-cis polydienes with a Mooney viscosity between 30 and 55 while allowing the use of lower amounts of catalyst.

A pressure-sensitive adhesive sheet for covering according to an embodiment of the present invention includes a non-crosslinked rubber component having a maximum peak of the molecular weight distribution in the range of 50,000 to 3,000,000, an oil component having a maximum peak of the molecular weight distribution in the range of 1,000 to 20,000, and carbon black. The content of the non-crosslinked rubber component is 25% to 65% by mass, the content of the oil component is 35% to 75% by mass, and the content of the carbon black relative to 100 parts by mass of the total of the non-crosslinked rubber component and the oil component is 1 to 40 parts by mass.

A pressure-sensitive adhesive sheet for covering according to an embodiment of the present invention includes a non-crosslinked rubber component having a maximum peak of the molecular weight distribution in the range of 50,000 to 3,000,000, an oil component having a maximum peak of the molecular weight distribution in the range of 1,000 to 20,000, and carbon black. The content of the non-crosslinked rubber component is 25% to 65% by mass, the content of the oil component is 35% to 75% by mass, and the content of the carbon black relative to 100 parts by mass of the total of the non-crosslinked rubber component and the oil component is 1 to 40 parts by mass.

A method for producing a polydiene, the method comprising of combining a lanthanide compound, an alkylating agent, a halogen source, and optionally conjugated diene monomer to form an active preformed catalyst; independent of step (i), introducing an amine with conjugated diene monomer to be polymerized; independent of step (i), introducing the active preformed catalyst to the conjugated diene monomer to be polymerized to form an active polymerization mixture, where the active polymerization mixture includes less than 10% by weight, based on the total weight of the active polymerization mixture, of a solvent; and allowing the monomer to be polymerized to polymerize in the presence of the amine.

A method for producing a polydiene, the method comprising of combining a lanthanide compound, an alkylating agent, a halogen source, and optionally conjugated diene monomer to form an active preformed catalyst; independent of step (i), introducing an amine with conjugated diene monomer to be polymerized; independent of step (i), introducing the active preformed catalyst to the conjugated diene monomer to be polymerized to form an active polymerization mixture, where the active polymerization mixture includes less than 10% by weight, based on the total weight of the active polymerization mixture, of a solvent; and allowing the monomer to be polymerized to polymerize in the presence of the amine.

A method for producing a polydiene, the method comprising of combining a lanthanide compound, an alkylating agent, a halogen source, and optionally conjugated diene monomer to form an active preformed catalyst; independent of step (i), introducing an amine with conjugated diene monomer to be polymerized; independent of step (i), introducing the active preformed catalyst to the conjugated diene monomer to be polymerized to form an active polymerization mixture, where the active polymerization mixture includes less than 10% by weight, based on the total weight of the active polymerization mixture, of a solvent; and allowing the monomer to be polymerized to polymerize in the presence of the amine.

The present invention relates to a modified polymerization initiator for a conjugated diene-based polymer, and a modified conjugated diene-based polymer including a functional group derived from the modified polymerization initiator.

The present invention relates to a modified polymerization initiator for a conjugated diene-based polymer, and a modified conjugated diene-based polymer including a functional group derived from the modified polymerization initiator.

The present invention discloses thiol compositions containing monothiotricyclodecenes, dithiotricyclodecanes, and intermolecular sulfide compounds, as well as mining chemical collector compositions containing such thiol compositions. Flotation processes for recovering metals, such as copper and molybdenum, from ores using the mining chemical collector compositions also are disclosed.

The present invention provides 1,4-cis polybutadiene having high linearity with an −S/R value of 1 or greater at 100° C., and accordingly, is capable of reducing resistance properties, particularly rolling resistance, and greatly enhancing fuel efficiency properties when used in a rubber composition.