PerspectiveMaterials Science

Approaching Asymmetry and Versatility in Polymer Assembly

See allHide authors and affiliations

Science  03 Aug 2012:
Vol. 337, Issue 6094, pp. 530-531
DOI: 10.1126/science.1225524

You are currently viewing the summary.

View Full Text

Log in to view the full text

Log in through your institution

Log in through your institution


Modern integrated circuits are produced in a “top-down” approach with the aid of lithographic techniques to sequentially control the etching and deposition of materials. Arbitrary nanoscale shapes can be created in a desired hierarchical sequence to produce a functional device. If assembled with no control of size, shape, or sequence, the same materials produce no function and no technology. In contrast to lithography, “bottom-up” solution processing can assemble nanoscale polymeric materials in a simple manner, often through aggregation and phase separation processes driven by multiple weak interactions and the minimization of free energy (1). Unfortunately, bottom-up products are usually relatively simple and symmetrical (e.g., spherical and cylindrical micelles, bilayer membranes, and spherical colloids). On page 559 of this issue, Rupar et al. (2) present a beautiful example of complexity and arbitrary control of solution-grown nanomaterials. The authors combined aspects of sequential, top-down control with bottom-up simplicity by using molecular design, solution assembly, crystallization, and covalent cross-linking chemistry in a multistep fashion.