SYNTHESIS OF INTRAMOLECULARLY CYCLIZED POLY(PHENYLENE SULFIDE)S OF THE THIANTHRENE-TYPE

Oligomers containing thianthrene units in the chain are synthesized by AlCl3-catalyzed reaction of diphenylsulfide, thianthrene, poly(p-phenylene sulfide), and poly(m-phenylene disulfide) with sulfur at 80°C. The products are compared with that obtained by the reaction of diphenylsulfide with AlCl3 at 225°C. IR spectra and elemental analyses are consistent with cyclic chain structures and show a higher cyclization for CHCl3-insoluble fractions. X-ray diffraction analysis indicates the same structure for the samples obtained with the different methods of synthesis. A possible structural model is tentatively proposed.