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A solid-state sulfonation procedure on syndiotactic polystyrene (s-PS) ?formfilms allows an easy and uniform sulfonation of the phenyl rings of the amorphous phase and preserves the nanoporous ?-phase. The high degree of sulfonation of the amorphous phase (up to a molar ratio 2/1 between phenyl rings and sulfonic groups) makes this phase highly hydrophilic, whereas the hydrophobic crystalline phase maintains its guest sorption ability. s-PS films, sulfonated only in the amorphous phase and exhibiting the nanoporous d-phase, present kinetics of guest sorption from water solutions into the crystalline phase, being markedly higher than those of the corresponding unsulfonated films. For instance, DCE sorption kinetics from 50 ppm aqueous solutions show an unaltered DCE equilibrium uptake (close to 4 wt %) associated with a DCE diffusivity increase of more than 70 times. Moreover, the nanoporous crystalline phase and its sorption ability remain essentially unaffected by water sorption/desorption cycles. The reported results hence indicate that these new materials are particularly suitable for removal of VOC pollutants from water and moist air. © 2009 American Chemical Society.

A preliminary model for the crystal structure of form III of isotactic poly(4-methylpentene-1) is suggested on the basis of structure factor calculations. Chains in 4(1) helical conformations are packed in a tetragonal unit cell with axes a = 19.38 angstrom and c = 6.98 angstrom; the space group is I4(1). The polymorphic behavior of poly(4-methylpentene-1) is discussed on the basis of conformational energy calculations on the isolated chain. The presence of different modifications is in accordance with energy minima present in the conformational energy map.