Solvent Effects in Alternating ADMET Polymerization

Alternating AB copolymers were synthesized by exploiting the selectivity of the metathesis reaction between α,ω-dienes and α,ω-diacrylates. Unlike standard acyclic diene metathesis (ADMET) polymerizations, the copolymerization of dienes and diacrylates does not require high vacuum conditions. This work utilizes this unique characteristic to explore the effect of various solvents on ADMET polymerization. We found significant variation in the efficacy of the solvents we screened, with CH₂Cl₂ yielding the highest molecular weight polymer. Additionally, the performance of Grubbs second generation catalyst was compared with Hoveyda-Grubbs second generation catalyst in different solvents, revealing a stark difference in the molecular weight of the resulting polymers in CH₂Cl₂ but a relatively minor difference in the final molecular weight from polymerizations in acetic acid.