Novel Polyquinolines: Synthesis and Properties

Novel polyquinolines containing main-chain 6,6'-oxybiquinoline fragments and differing in the nature of side ester groups are synthesized. The obtained initial compounds and polymers are studied by IR and NMR spectroscopy, HPLC, simultaneous thermal (thermogravimetric and differential thermal) analysis, and scanning electron microscopy, and their mechanical characteristics, degrees of swelling, and contact angles are estimated. Diffusion membranes prepared from all synthesized polymers are tested in the pervaporation separation of isopropyl alcohol–water mixture. It is shown that the structure and physicochemical and transport properties of the membranes based on the mentioned polyamides considerably depend on the presence of carboxyl groups, as well as methoxy and ethoxy ester groups in biquinoline fragments.