Ab-initio electrostatic molecular potential contour maps for initiation step and Ab-Initio MRD-CI calculations for propagation step of cationic polymerization of oxetanes

The initiation step in the cationic polymerization of cyclic ethers is influenced by basicity and ring strain. We carried out ab-initio MODPOT/VRDDO/MERGE calculations on a variety of substituted oxetanes and generated electrostatic molecular potential contour (EMPC) maps in three-dimensions around the molecules. The size of the negative EMPC map region around the oxygen enabled us to predict the propensity to polymerize prior to the syntheses of the actual monomers themselves. We carried out ab-initio MODPOT/VRDDO/MERGE MRD-CI calculations for the propagation step of oxetane reacting with protonated oxetanes to cause ring opening of protonated oxetane. Similar MRD-CI calculations on variously substituted oxetanes will shed insight into relative copolymerization preferences.