Synthesis and properties of elastomeric ionenes I. Polybutadiene ionenes

Abstract Polybutadiene ionene (PBI) carrying quaternary ammonium ions in the main chain was synthesized from dimethylamino‐terminated polybutadiene and 1,4‐dibromobutane. Dimethylamino‐terminated polybutadiene was prepared by the reaction of isocyanate‐terminated polybutadiene with 2‐dimethylaminoethanol. The swelling property and the mechanical properties of PBI were compared with those of polybutadiene urethane (PBU), which was prepared by the reaction of hydroxy‐terminated polybutadiene with a diisocyanate. The following points were found: (1) PBI shows almost the same solubility parameter δp as that of PBU; (2) PBI attains a four time greater tensile strength at break than PBU at room temperature; (3) PBI shows a thermoplastic behavior.