Study on complexing behavior of the syndiotactic polystyrene-aromatic hydrocarbon system Original Research Article

Guest molecular dynamics related to the stable complexing behavior of syndiotactic polystyrene (sPS)-xylene isomer (m- and p-xylene, abbreviated MX and PX) complexes have been characterized by solid-state 13C-NMR spectroscopy. Similar chemical shifts are observed for both sPS complexes in the 13C-CP/MAS spectrum. Interestingly, the solvent resonance of methyl carbon could be observed under CP conditions, indicating the relative rigidity of the solvent. Inversely, the sPS-MX system showed doublet peaks at 21.8 and 23.2 ppm when compared with the atactic PS-MX system, suggesting the orderly arrangement of the methyl group in the complexed system. The mobility of the guest molecule in the system is evaluated using spin-lattice relaxation time (T1c). Moreover, the mobility of helical chains of sPS is also inferred from its T1c. Hence, the influence of the mobility of the methyl carbon of xylene and the sPS helical chain could be investigated, which helps in studying the complexing behavior of the sPS-xylene system.