Monomer sequence control via living anionic copolymerization: Synthesis of alternating, statistical, and telechelic copolymers and sequence analysis by MALDI ToF mass spectrometry

Diphenylethylene (DPE) is a monomer which has attracted significant interest from both academia and industry. DPE can undergo (co)polymerization by living anionic polymerization but is incapable of forming a homopolymer due to steric hindrance. Herein the copolymerization of DPE and 1,1-bis(4-tert-butyldimethylsiloxyphenyl)ethylene (DPE-OSi) with styrene or butadiene is described in order to produce (functional) copolymers with controlled comonomer sequences-either alternating or telechelic. The copolymer sequences are inherently controlled by relative reactivity ratios, which in turn can be tuned by both monomer structure and the polarity of the polymerization solvent. The compositions of the copolymers prepared in this study were analyzed by ¹H NMR spectroscopy and MALDI ToF mass spectrometry, the latter offering a unique opportunity to demonstrate perfect alternating sequences and insight into other sequences such as telechelic polymers.