Application of methyl cinnamate montmorillonite as ultraviolet radiation shelters

The interaction of methyl cinnamate/montmorillonite samples prepared by melting the former onto the second or by joint grinding, has been studied by x-ray diffraction, differential thermal analysis, thermogravimetric analysis and Fourier-transform infrared spectroscopy. Formation of an interlayer compound has been observed, leading to an increase of 4.15 or 3.42 Angstrom (samples obtained by melting or grinding, respectively) in the basal spacing of the clay. Formation of such a complex leads to a displacement of molecular water from the interlayer space, as concluded from the thermal studies. No chemical change is observed in the methyl cinnamate molecule, as confirmed by infrared spectroscopy. The systems prepared improve the shelter properties of the clay and the drug separately, mainly in the C zone of the ultraviolet spectrum (290-190 nm).