New Developments in Colloid Science
Original entry: Xu Zhang, APPHY 225, Fall 2009
Contents
Reference
New Developments in Colloid Science D.A. Weitz and W.B. Russel, MRS Bull. Feb 2004 83 (2004)
Keywords
colloids, colloidal materials, "directed" assembly, rheology, suspensions
Summary
This article summarizes several new developments of colloid science in two aspects: "directed" assembly of colloidal particles and understanding in rheology of colloidal suspensions.
Directed Assembly
Various methods
1) Using depletion interaction
Controllable elements: 1.surface treatment 2.solvent choice 3.addition of other materials
2) Applying additional stresses ( Van Blaaderen ) Ex. a hard wall that restricts the states of the colloidal suspension, electric and magnetic fields, surface stresses induced by drying, oder imposed by patterned surfaces, gravitational effects,etc.
3)Using interactions between colloidal particles k_B T
Main Obstacle
The surface energy drives the interface of the particle to be spherical, which places fundamental limitations on the structures that can be built.An important limitation comes in making photonic-bandgap structures