Layering Transitions of Ribbon Polymers in Poor Solvents Yasuo Y. Suzuki Faculty of Engineering, Takushoku University, Hachioji, Tokyo 193-0985, Japan D. R. M. Williams Research School of Physical Sciences, Australian National University, Canberra, ACT 0200, Australia 1. Ribbon Polymers 3. Layering Transitions in Tubular Condensates Anisotropic semiflexible polymers in biotechnology and nanotechnology DNA, ladder polymers, conducting polymers Free energy Bending energy Size of Tubular Ribbon For a circular ring of radius R Ro n Surface energy Ri Tubulus Multilayer Annuli L 2. Ribbon Polymers in Poor Solvents (Annular Condensates) We found that these condensates undergo a number of distinct layering transitions as a function of ribbon length or surface tension: a sudden jump in Ro at the transition from n to n+1 layers. This quantization is a direct consequence of the anisotropic elasticity. Free energy Volume conservation 4. A Special Example (Helix Condensates) Annulus The anisotropy depends heavily on the details of chemical bonding. Fluctuations Fluctuations will be less than the annular thickness. The annular will be well-defined and relatively flat. Helix