Creating new supramolecular materials by architecture of three-dimensional nanocrystal fiber networks

J Am Chem Soc. 2002 Dec 18;124(50):15055-63. doi: 10.1021/ja0206137.

Abstract

The architecture of three-dimensional interconnecting self-organized nanofiber networks from separate needlelike crystals of L-DHL (lanosta-8,24-dien-3beta-ol:24,25-dihydrolanosterol = 56:44) in di-isooctylphthalate has been achieved for the first time, on the basis of the completely new concept of branching creation by additives (branching promoters). [In this work, an additive, ethylene/vinyl acetate copolymer (EVACP), is used at a concentration of several 10 ppm.] We demonstrate that this novel technique enables us to produce previously unknown self-supporting supramolecular functional materials with tailormade micro- or nanostructures, possessing significantly modified macroscopic properties, by utilizing materials thus far considered to be "useless". In addition, both the self-organized structure and the properties of the new materials can be fine-tuned by altering the processing conditions. Our results show that the formation of the interconnecting 3D self-organized network structure is controlled by a new mechanism, so-called crystallographic mismatch branching mechanism, as opposed to the conventionally adopted molecular self-assembly mechanism. The principles and criteria for the selection of branching promoters are also discussed from the point of view of molecular structures.

MeSH terms

  • Drug Delivery Systems
  • Entropy
  • Lanosterol / analogs & derivatives*
  • Lanosterol / chemistry
  • Nanotechnology / methods*
  • Phthalic Acids / chemistry*
  • Rheology
  • Sterols / chemistry*

Substances

  • Phthalic Acids
  • Sterols
  • diisooctyl phthalate
  • Lanosterol
  • phthalic acid
  • lanostenol