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Updated: Aug 12, 2026

Self-assembling Morphologies Obtained from Helical Polycarbodiimide Copolymers and Their Triazole Derivatives
Published on: February 7, 2017
Helical structure of sugar-carrying polystyrene in aqueous solution by circular dichroism
Shojiro Shimojo1, Chong-Su Cho, In-Kyu Park
1Department of Biomolecular Engineering, Tokyo Institute of Technology, 4259 Nagatsuta-cho Midori-ku, Yokohama 226-8501, Japan.
Abstract:
Radical polymerization of N-p-vinylbenzyl-D-lactonamide (VLA) gave an optically active helical polymer. The stereoregularity of poly(N-p-vinylbenzyl-D-lactonamide) (PVLA) measured by 13C NMR spectroscopy showed a well-resolved sharp-line width, which was assigned to the phenyl C-1 carbon of the isotactic polystyrene (PS). The helical structure of PVLA shown by circular dichroism (CD) indicated that the aromatic groups were chirally supramolecular-packed giving optically active disaccharide units in the side chain covalently linked via an amide linkage with PS, the original PS not being optically active. The intensity of CD for PVLA (a) decreased with increasing temperature due to the change in the conformation of the phenyl group or to the breakdown of intermolecular hydrogen bonding of amide groups and (b) increased in a mixture of water and alcohol due to the increased hydrophobicity. The CD intensity for maltose-carrying PS (PVMA) was slightly higher than that of PVLA CD due to the more hydrophobic property of PVMA than PVLA.
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