Abstract
Polydiacetylene nanocrystals prepared by the reprecipitation method usually have non spherical shapes and a wide size distribution. It is difficult to arrange this nonlinear optical material into highly ordered photonic crystals by self-assembly. Enclosing of polydiacetylene nanocrystals in monodispersed polystyrene shells by seeded emulsion polymerization of styrene provided one solution to this problem. The polydiacetylene nanocrystals in thus prepared composite particles maintained their crystal structure and their optical properties.