I.r. spectra and temperature dependences of 1H n.m.r, linewidths were measured for poly(p-phenylene sulphide) (PPS) heavily doped with sulphur trioxide (SOa) in the form of vapour and liquid. X-ray diffraction studies confirmed the total destruction of the crystalline phase as a result of the doping process. I.r. spectra show that doping with SO3 leads to irreversible chemical modifications of the polymer by sulphonation. A comparison of the experimental values of the n.m.r, second moment determined for a rigid structure of the doped PPS with the poly(benzothiophene) excludes the formation of the latter as a result of doping. Doping with SO3 in the vapour form leads to structural changes in the polymer with its two-phase character preserved. Annealing of the doped sample at 450 K results in the removal of chemically unbonded SO3. However, the annealed polymer still has a different structure from the pristine polymer. PPS doped with liquid SO 3 shows a monophase structure indicated by a liquid-like resonance line.
Посилання на статтю:
I.r. spectroscopy and 1H n.m.r, broad line studies of poly(p-phenylene sulphide) doped with sulphur trioxide / P. Hruszka and J. Jurga // Polymer. – 1992. – Vol 33. – P. 248-253.