Optically active vinyl polymers containing fluorescent groups—7: The distribution of monomeric units in cationically prepared copolymers of 9-vinylcarbazole and (−)menthyl vinyl ether

Abstract

u.v. Absorption, 1H-NMR, fluorescence emission and circular dichroism spectra together show clearly that stereoregular copolymers obtained cationically from 9-vinylcarbazole and (−)menthyl vinyl ether have significant block-like character. In contrast to results for related optically active copolymers, plots of circular dichroism absorption intensity versus copolymer composition exhibit a pronounced maximum corresponding to a molar composition 20% 9-vinylcarbazole, 80% (−)menthyl vinyl ether. This maximum does not correspond, as expected, with the presence of isolated carbazole units in a chiral polymer environment.