OBSERVATION OF EDGE DISLOCATIONS IN ORDERED POLYSTYRENE LATEXES

The Grandjean-Friedel-Cano wedge geometry is used to produce well controlled edge dislocation patterns in ordered latexes. Due to the strain field, the color of the Bragg reflected light is found to be modified, making the dislocations easily visible in a metallurgical microscope. An estiamte of the elastic energy stored in this strain field is made. The minimum energy configuration fo the dislocation is found to agree with that observed experimentally.