Dispersion and alignment of organic-clay composites within polysilicate thin films by the sol-gel method

Montmorillonite clay fine particles containing alkylammonium or pyridinium guests have been observed to be highly dispersed and aligned in thin films of sol-gel polysilicate networks spin-coated on quartz slide glasses. Polar ized UV and visible spectroscopic analyses of the films indicate that the o rganic guests are aligned not only with the interlayer surfaces of the clay s but also with the sol-gel polysilicate thin films. SEM and XRD observatio ns also confirm the anisotropic disposition of the guest molecules in the c omposite thin films. This is in stark contrast to the case of randomly orie nted clay films prepared by the casting of the suspension on slides without any matrix.