Reversible Addition−Fragmentation Transfer Polymerization of a Novel Monomer Containing Both Aldehyde and Ferrocene Functional Groups

A new monomer, 2-formal-4-vinylphenyl ferrocenecarboxylate (FVFC), containing both aldehyde and ferrocene functional groups was designed and prepared by the reaction of ferrocenecarboxylic acid chloride with 2-hydroxy-5-vinylbenzaldehyde. The controlled radical polymerization of FVFC was achieved using 2,2'-azobis(isobutyronitrile) (AIBN) as the initiator and 2-cyanopropyl-2-yl dithiobenzoate (CPDB) as the reversible addition-fragmentation chain transfer (RAFT) agent at 60 degrees C in tetrahydrofuran (THF). The polymerization nearly followed first-order kinetics, the number-average molecular weight of the obtained polymers increased almost in direct proportion to the monomer conversion, and the molecular weight distribution was narrow (polydispersity index < 1.2). The chain and terminal structures of the obtained polyFVFC were confirmed by H-1 NMR and matrix-assisted laser desorption-ionization time-of-flight mass spectrometry analysis. The obtained polyFVFC can be employed as a macro-RAFT agent for styrene polymerization, resulting in polyFVFC-b-polystyrene.