GLASS-FORMING ABILITY AND MORPHOLOGICAL STABILITY OF CYCLOHEXANE AND BIOCYCLOOCTENE RINGS CONTAINING DISPERSE RED-1

To evaluate the effects of chemical structure on the ease of vitrifica tion, morphology, and its stability against thermally activated crysta llization, disperse red 1 (DR1) was employed to synthesize di- and tri substituted cyclohexanes and a tetrasubstituted bicyclooctene. The res ultant glass-forming molecular materials were characterized with the P OM, DSC, and XRD techniques across a temperature range from 25 to 225 degrees C. The results suggest that the DR1 derivatives of cis-1,2-cyc lohexanedicarboxylic, 1,3,5-cyclohexane tricarboxylic, and bicyclo[2.2 .2]oct-7-ene-2,3,5,6-tetracarboxylic acids yield morphologically stabl e glasses, with an ascending T-g from 51 to 73 and 98 degrees C, respe ctively; however, a pristine sample of the first ester was found to be crystalline and those of the other two esters completely amorphous, a n indication of a stronger glass-former. In the series of disubstitute d cyclohexanes, T-g was found to fall within a narrow temperature rang e from 45 to 52 degrees C, whereas a great deal of variations in morph ology and its stability were observed depending on the position of sub stitution and stereochemistry.