Block copolymers of monovinylarenes and conjugated dienes containing two interior tapered blocks

A method of preparing a copolymer under polymerization conditions in a reaction zone comprising:

• (a) charging a monovinylaromatic monomer and an initiator and in the presence of a randomizer allowing polymerization to occur until essentially no free monomer is present;
• thereafter
• (b) charging an initiator and a monovinylaromatic monomer and allowing polymerization to occur until essentially no free monomer is present;
• thereafter
• (c) charging a mixture of monovinylaromatic monomer and conjugated diene monomer and allowing polymerization to occur until essentially no free monomer is present;
• thereafter
• (d) charging a mixture of monovinylaromatic monomer and conjugated diene monomer and allowing polymerization to occur until essentially no free monomer is present;
• thereafter
• (e) charging a conjugated diene monomer and allowing essentially complete polymerization to occur until essentially no free monomer is present;
• and thereafter
• (f) charging the reaction mixture with a coupling agent, wherein only two initiator charges are present and are performed as stated in steps (a) and (b).