[Determination of the Molecular-weights and the Molecular-weight Distributions of a Semicrystalline Poly(aryletherketone-co-sulfone) (htx) By a Chemical Derivatization Method .1. Molecular Characterization of Htx Solved in Concentrated Sulfuric-acid]

HTX, a poly(aryletherketone-co-sulfone), is characterized in solution in concentrated sulfuric acid. Upon dissolution in concentrated H2SO4, HTX is chemically modified by sulfonation of phenyl rings. The modification of the chemical structure is studied with a model compound by means of IR spectroscopy. The increase of the molar mass corresponding to a complete sulfonation is determined by means of mass spectrometry. Light scattering and F-19 NMR measurements are performed in order to obtain the weight- (M(w)BAR)s and number-average (M(n)BAR)s molar masses of sulfonated HTX samples. (M(w)BAR)s values allow the determination of the Mark-Houwink-Sakurada relationship for HTX in 99,5% H2SO4 at 25-degrees-C