Computational Study of Ring Opening Polymerization in Substituted Benzoxazines – Electron Density Analysis and Role of Intra-molecular and Inter-molecular Interactions
in partial fulfillment of the requirements for the degree of Bachelor of Science (Research)
Substituted furan-benzoxazine systems have been studied taking the cue from experimental work done on monosubstituted and disubstituted benzoxazines. Phenyl groups are looked at as functional groups of interest Ab initio treatment of the substituted benzoxazines followed by electron density analysis reveals the role of functional groups in intra-atomic and interatomic electron density and energy contributions. Intermolecular effects were studied using molecular dynamics simulations. Molecular dynamics simulations further support the proposed mechanism where the strained oxazine ring opens to form an iminium ion in the initial step of polymerisation process. Transition states were obtained for furan-substituted benzoxazine and minimised geometries were obtained for phenyl-substituted furan benzoxazine. Changes in interatomic energy contribution were seen, along with insights from electron density distribution. Strong evidence for the nature of the oxazine ring is presented, from a variety of quantum chemical perspectives.