PHYSICAL STUDIES OF IONICALLY-TERMINATED POLYTETRAHYDROFURAN .2. APPLICATION OF THE MARK-HOUWINK RELATION AND DETERMINATION OF UNPERTURBED MOLECULAR DIMENSIONS

Tetrahydrofuran polymers terminated at one end with a pyridinium bromide group were prepared and their hydrodynamic behaviour contrasted with the equivalent methoxy-terminated polymers. The hydrodynamic behaviour of methoxy-terminated polytetrahydrofuran in cyclohexane, toluene, tetrahydrofuran, methyl ethyl ketone and cyclohexanone and (pyridinium bromide)-termined polytetrahydrofuran in tetrahydrofuran, methyl ethyl ketone and cyclohexanone was consistent with that of partially free-draining random coils. In cyclohexane and toluene, the pyridinium bromide-terminated polymers possess aggregated structures (multiplets). These multiplets contain between 2 to 3 ionic chain ends.