Functionalization of amphiphilic coil-rod-coil triblock copolymer poly(2-vinylpyridine)- b-poly( n-hexyl isocyanate)- b-poly(2-vinylpyridine) with florescence moiety and C 60
We recently achieved quantitative synthesis of an amphiphilic coil-rod-coil triblock copolymer, poly(2-vinylpyridine)-b-poly(n-hexyl isocyanate)-b-poly(2-vinylpyridine), by coupling in situ living diblock copolymer poly(2-vinylpyridine)-b-poly(n-hexyl isocyanate) (P2VP-b-PHIC) using malonyl chloride in the presence of pyridine. This led to the introduction of an active methylene group that is a site for further functionalization in the rod block. The Michael addition reaction of the triblock copolymer with 7-(4-trifluoromethyl) coumarin acrylamide led to copolymer bearing a fluorescent pendent in the rod block. The fluorescent labeled copolymers were isolated in ∼94% yields. Similarly C60 pendent was introduced to the rod block by the Bingel reaction. The yields of C60 functionalized copolymers were ∼54%. The precursor and functionalized amphiphilic coil-rod-coil copolymer show diverse morphologies, such as micelles and vesicles by simply changing the solvent. For the C60 functionalized block copolymer, structural constraints in micelles and vesicles prevented C60 pendents to aggregate.
, vol. 52, no. 9, pp. 1925-1931, 2011