MOLECULAR CHARACTERIZATION OF POLY(P-PHENYLENE SULFIDE) (PPS) FROM SIZE-EXCLUSION CHROMATOGRAPHY OF A MODIFIED PPS AND DILUTE-SOLUTION PROPERTIES

A new method for poly(p-phenylene sulfide) (PPS) molecular mass charac terization by size exclusion chromatography (s.e.c.) at 75 degrees C b ased on a derivatization procedure, improving the polymer solubility, is proposed. This procedure leads to the preparation of a poly(p-pheny lene sulfoxide) (PPSO) polymer. As complete oxidation is achieved, the reproducibility of the chemical modification is ensured as well as th e increase of molecular mass. Furthermore, the molecular mass distribu tion is preserved for all that the PPS macromolecule only contains sul fide linkages and halogenoaryl chain ends. Molecular characterization of PPSO by light scattering, viscometry and s.e.c. is described. A Mar k-Houwink-Sakurada relationship in m-cresol + 0.1 M LiBr is establishe d. From specific and universal calibrations, absolute molecular masses of PPSO are obtained by s.e.c. The study of PPSO conformation in dilu te solution reveals that the PPSO macromolecule can be considered as a freely rotating chain with ca 104-110 degrees valence angles. The sig ma factor is close to 1. Copyright (C) 1996 Elsevier Science Ltd.