Effects of solvent on initiated reaction of maleic anhydride polymerization

This work discusses the effect of solvent on the polymerization of maleic anhydride (MA) at the initiation stage with hydroxyl (OH−) was an initiator. The standard Density Functional Theory (DFT) with Becke's hybrid function (B3LYP/6-311G**) method was employed to predict the transition states (TS) during the initation reaction. In addition, another highly accurate ab initio method MP2 was applied to correct single point energies. On the basis of calculated gas-phase results, we use the Polarizable Continuum Model (PCM) with varied dielectric constants to evaluate the contribution of solvents on the structure and thermodynamic properties of proposed intermediates and transition states. Our data suggests that solvents play an important role in optimizing the geometries, which results in a significant reduction of the activation energy ΔE for the rate-determining step. Furthermore, we found polarizable fields decrease free energy ΔG for the rate-determining step, leading to the acceleration of the initiated reaction.