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. Polarized UV and visible spectroscopic analyses of the films indicate that the organic guests are aligned not only with the interlayer surfaces of the clays but also with the sol-gel polysilicate thin films. SEM and XRD observations also confirm the anisotropic disposition of the guest molecules in the composite thin films. This is in stark contrast to the case of randomly oriented clay films prepared by the casting of the suspension on slides without any matrix.