Preparation and crystallization behavior of syndiotactic polystyrene-clay nanocomposites

Syndiotactic polystyrene/modified-clay nanocomposites have been prepared by solution blending by mixing pure s-PS and organophilic clay with adsorbed cetyl pyridium chloride (CPC) in dichlorobenzene. The dispersability of the clay in syndiotactic polystyrene/modified-clay nanocomposites was studied using X-ray and transmission electron microscopy. The clay is well dispersed into the s-PS matrix using solution blending with scale in 1-2 nm or in a few tenths similar to 100 nm depending on surfactant treatment. The CPC is partially compatible with s-PS and allows syndiotactic polystyrene chains intercalating into clay layers. The crystallization behavior of alpha- and beta -crystals for syndiotactic polystyrene nanocomposite has been thoroughly examined using the Fourier transform infrared and differential scanning calorimetry. Our results further demonstrate that the presence of the clay plays a vital role in facilitating the formation on the thermodynamically more favorable beta form crystal when the s-PS is melt- or cold-crystallized. (C) 2001 Elsevier Science Ltd. All rights reserved.