SPECTROSCOPIC AND THERMAL STUDIES OF SULFONATED SYNDIOTACTIC POLYSTYRENE

Sulfonation of highly stereoregular syndiotactic polystyrene has been accomplished in chloroform. The sulfonation can be well controlled and carried out to a higher degree than previously reported. The crystallization behavior of sulfonated syndiotactic polystyrene exhibits considerable differences in comparison to the neat sample. Both extended all-trans and ttgg helical chain conformations have been observed for the sulfonated samples. The melting temperatures observed range from 245 degrees C for the 6.3 mol % sample to 266 degrees C for the 1.4 mol % sample. The glass transition temperature is also perturbed by the sulfonation procedure. The irreversible transition from the helical to the all-trans chain conformation can be accomplished at 175 degrees C, much lower than observed for the neat sample. The temperature range for this transition is extremely broad, taking place from 160 to 190 degrees C.