Molecular Gels and their Fibrillar Networks - Soft Fibrillar Materials: Fabrication and Applications - page 3

0D TOPOLOGY

1D

TIME

Nucleated
(microcrystallites)

Aggregate Fiber

Solution/sol

SAFIN
(3D)

0.5 μ m

Figure 1.1 Cartoon representation of the
steps in the evolution of LMOG s (0D ob-
jects; tear drops) to fibers (1D objects) and,
in some cases, to SAFIN s(3-Dobjects)in

liquids (wavy lines). Lower left is a freeze-
fracture electron micrograph of a SAFIN .
Reprinted with permission from Ref. [11].
Copyright 1989 American Chemical Society.

gels. In his ''structural classification of gels,'' Flory included those starting with 0D
molecules as an afterthought, naming them ''particulate, disordered structures''! [8]
Although much has been learned during the last decade about the supramolecular
assembly of polymeric chains (topologically 1D objects) into a variety of 2D and 3D
objects [9, 10], much less is known about the initial steps that take 0D molecules to
1D objects, such as fibers, rods, tapes, and nanotubes (Figure 1.1); for the purposes
of this chapter, all of these high-aspect-ratio objects will be designated as ''fibers'',
regardless of the details of their shape, unless specified otherwise for purposes of
differentiation.

O

O

O

O

HO

OH

1