STUDY OF CHROMOTROPIC PROPERTIES OF COLORANTS

Abstract : In order to explore technical feasibility regarding the use of chromotropic colorants for a ''chameleon'' type camouflage system, photochromic, thermochromic, and chemochromic systems have been studied. Where possible, simple theoretical models for the various systems were analyzed mathematically to establish the thermodynamic and kinetic quantities which a suitable system must possess. Known compounds, representative of the three chromtoropic classifications, were examaned experimentally in both solution and polymer media. Consideration of the theoretical presently offer the most feasible approach for a chromotropic camouflage system. Of the presently available photochromic systems which were examined, the system based upon dithizone and its metal complexes--particularly Hg(II)--showed the most promising results. The dithizonate system should provide a useful model system for future synthetic and physical chemical work in this area. (Author)