2-Methoxycarbonyl-3-(3,4-dimethoxyphenyl)oxirane was synthesized and polymerized using a cationic initiator to afford a polymer having a rather stiff, stretched conformation. The side-chain methoxycarbonyl group and 3,4-dimethoxyphenyl group of neighboring monomeric units may form a hetero π-stacked structure between side-chain carbonyl and aromatic groups which leads to intramolecular charge transfer (ICT) interactions. 2-Ethoxycarbonyl-3-phenyloxirane failed in polymerization, leading only to small molecules including cyclic compounds.