A polymer production method whereby: a flow reactor comprising a flow path wherein a plurality of liquids can be mixed is used; and a monomer is anionically polymerized in the presence of an initiator. The flow reactor comprises a mixer for mixing two liquids, said mixer comprising either a joint member having a double pipe therein or a static mixer member.

A polymer production method whereby: a flow reactor comprising a flow path wherein a plurality of liquids can be mixed is used; and a monomer is anionically polymerized in the presence of an initiator. The flow reactor comprises a mixer for mixing two liquids, said mixer comprising either a joint member having a double pipe therein or a static mixer member.

A polymer production method whereby: a flow reactor comprising a flow path wherein a plurality of liquids can be mixed is used; and a monomer is anionically polymerized in the presence of an initiator. The flow reactor comprises a mixer for mixing two liquids, said mixer comprising either a joint member having a double pipe therein or a static mixer member.

A polymer production method whereby: a flow reactor comprising a flow path wherein a plurality of liquids can be mixed is used; and a monomer is anionically polymerized in the presence of an initiator. The flow reactor comprises a mixer for mixing two liquids, said mixer comprising either a joint member having a double pipe therein or a static mixer member.

The present disclosure provides a method for manufacturing with high productivity a modified polymer equivalent to the prior art blend of a modified polymer for matrix of a rubber composition and the low-molecular weight polymer. Specifically, a method for manufacturing a modified polymer, including continuously supplying a raw material monomer containing at least conjugated diene compound, a polymerization initiator containing lithium, 1,2-butadiene and a modification agent into a flow-through reactor, causing the raw material monomer to be continuously polymerized to generate polymer and also causing a portion of the polymer thus generated to be modified with the modification agent, is characterized in that: the polymerization and the modification are carried out at temperature equal to 110 C. or higher; and a mole ratio (1,2-Bd/Li) of the 1,2-butadiene (1,2-Bd) with respect to lithium (Li) of the polymerization initiator containing lithium is set to be 0.37 or less.

The present disclosure provides a method for manufacturing with high productivity a modified polymer equivalent to the prior art blend of a modified polymer for matrix of a rubber composition and the low-molecular weight polymer. Specifically, a method for manufacturing a modified polymer, including continuously supplying a raw material monomer containing at least conjugated diene compound, a polymerization initiator containing lithium, 1,2-butadiene and a modification agent into a flow-through reactor, causing the raw material monomer to be continuously polymerized to generate polymer and also causing a portion of the polymer thus generated to be modified with the modification agent, is characterized in that: the polymerization and the modification are carried out at temperature equal to 110 C. or higher; and a mole ratio (1,2-Bd/Li) of the 1,2-butadiene (1,2-Bd) with respect to lithium (Li) of the polymerization initiator containing lithium is set to be 0.37 or less.

A polymer production method whereby: a flow reactor comprising a flow path wherein a plurality of liquids can be mixed is used; and a monomer is anionically polymerized in the presence of an initiator. The flow reactor comprises a mixer for mixing two liquids, said mixer comprising either a joint member having a double pipe therein or a static mixer member.

A polymer production method whereby: a flow reactor comprising a flow path wherein a plurality of liquids can be mixed is used; and a monomer is anionically polymerized in the presence of an initiator. The flow reactor comprises a mixer for mixing two liquids, said mixer comprising either a joint member having a double pipe therein or a static mixer member.