Essentially water-free polymerized crystalline colloidal array composites having tunable radiation diffracting properties

A method for making a composite having tunable electromagnetic wave diffracting properties comprising the steps of:

• a) allowing colloidal particles to self-assemble into a crystalline colloidal array in a medium;
• b) adding at least one hydrogel-forming monomer to the medium containing the crystalline colloidal array;
• c) polymerizing the at least one hydrogel-forming monomer to form a polymerized crystalline colloidal array having a hydrogel matrix;
• d) dehydrating the hydrogel matrix of the polymerized crystalline colloidal array;
• e) swelling the dehydrated polymerized crystalline colloidal array with at least one monomer;
• and
• f) polymerizing the at least one monomer thereby forming an essentially water-free polymerized crystalline colloidal array.

A photonic composite having a tunable bandgap made by a process comprising the steps of:

• g) allowing colloidal particles to self-assemble into a crystalline colloidal array in a medium;
• h) adding at least one hydrogel-forming monomer to the medium containing the crystalline colloidal array;
• i) polymerizing the at least one hydrogel-forming monomer to form a polymerized crystalline colloidal array having a hydrogel matrix;
• j) dehydrating the hydrogel matrix of the polymerized crystalline colloidal array;
• k) swelling the dehydrated polymerized crystalline colloidal array with at least one monomer;
• and
• l) polymerizing the at least one monomer thereby forming an essentially water-free polymerized crystalline colloidal array;
• wherein the bandgap shifts responsive to environmental stimulation.