Living Anionic Polymerization of Functionalized Monomers, 2. Anionic Polymerization of p‐Alkenylstyrene Derivatives

A study has been carried out on the anionic polymerization of eight p‐alkenylstyrene derivatives. The monomers used are p‐(2‐propenyl)styrene ( 1 ), p‐(2‐propenyl)‐α‐methylstyrene ( 2 ), p‐(2‐butenyl)styrene ( 3 ), p‐(2‐butenyl)‐α‐methylstyrene ( 4 ), p‐(2‐methyl‐2‐propenyl)styrene ( 5 ), p‐(2‐methyl‐2‐propenyl)‐α‐methylstyrene ( 6 ), 8‐(p‐vinylphenyl)‐1‐octene ( 7 ), and 2‐methyl‐7‐(p‐vinylphenyl)‐1‐heptene ( 8 ). The anionic polymerizations of 1 – 4 were accompanied by competitive side reactions presumably due to the proton abstraction from their allyl groups. Furthermore, significant degrees of the propagating chain‐end carbanions derived from 1 , 3 , and 4 were deactivated in THF at –78°C after 1–2 h. In contrast, the polymerizations of 5 – 8 proceed in a living manner in THF at –78°C to afford polymers with predictable molecular weights and narrow molecular weight distributions. Novel well‐defined block copolymers of 5 – 8 with styrene or 2‐hydroxyethyl methacrylate were successfully prepared.