| Abstract: | Plasma-exposed solution polymerizations of carboxylic acid vinyl monomers methacrylic acid (MAA) and acrylic acid (AA)] in carbonyl solvents were found to be highly efficient, particularly in high-temperature postpolymerizations. Thermal polymerizations in these solvents were also accelerated to a considerable extent. Obviously the carbonyl solvents and/or the increased temperature caused the monomer aggregates to accelerate the rate of polymerization. The molecular orbital features of the simple models of monomer aggregates, that is, the monomeric form, singly hydrogen bonded open-dimer and doubly hydrogen bonded cyclicdimer of MAA and AA, supported by the CNDO/2 method, were capable of distinguishing the variations in the reactivities of the aggregates; the open-dimer was shown to be responsible for the enhanced reactivities under the abovementioned conditions. |
