In situ Synthesis from End-Capping of Living Anionic Polymers for ω-Norbornenyl Macromonomers, and Their Ring-Opening Metathesis Polymerization

Abstract

We report the preparation of ω-norbornenyl macromonomers (MMs) in an in situ manner. End-capping agent (NCXPA) was desingned and synthesized by using exo-norbornene and α-phenyl acrylate for living anionic polymerization. End-capping reaction of NCXPA with living anionic polymers successfully produeced both ω-norbornenyl polystyrene (NCXPS) and poly(methyl methacrylate) (NCXPMMA) with controlled molecular weights and low dispersities (Đ = 1.02-1.07). Ring opening metathesis polymerization (ROMP) of the resulting MMs displayed high end-capping efficiency of MMs (NCXPS ≥96% and NCXPMMA ~70%). ROMP showed the different results dpending on the length of alkyl spacer (NC6PA and NC10PA) and molecular weights (approximately 2, 3, and 5 kDa) of MMs. The longer alkyl spacer (NC10PA) and approximately 2 and 3 kDa of macromonomers afford well-defined bottlebrush polymers (low Đ = 1.02 ~ 1.13).