Response Of Imprinted Photonic Crystals For Nicotinamide In Aqueous Solution

Responsive hydrogel photonic crystal contacts with stimulus, the volume of the gel changes, thus causing Photonic band gap arising to give response. Molecular imprinting technique is recognized as a powerful technique of preparing synthetic polymers that contain tailor-made recognition sides for certain molecular. By combination of responsive colloid-crystal and molecular imprinting technique, molecular imprinting photonic crystals have been prepared. In this dissertation, nicotinamide (Nicotinamide, NA) imprinted poly(acrylamide-co-acrylic acid)(PAM-co-AA) inverse opal photonic crystals (NA-IPCs) were prepared by adding NA into monomers solution. The structural color and response of NA-IPCs to external environments have been investigated.Firstly, monodispersed polystyrene spheres have been synthesized by emulsion polymerization. Then single crystalline opal structural polystyrene template has been prepared by vertical deposition method.Secondly, PAM-IPCs were prepared by adding a certain amount of NA into monomer solution. We investigated the response behavior of PAM-IPCs and PAM non-imprinted photonic crystals (NIPCs) to NA solution at various concentrations. The results showed PAM-IPCs and PAM-NIPCs both got red-shifted with the increase in concentration of NA solution. The responding capacity of PAM-IPCs is much stronger than that of PAM-NIPCs.Thirdly, a series of PAM-co-AA-NA-IPCs were prepared by adding different amounts of NA into monomers solution. The degree of redshift increased with the adding amount of NA and decreased sharply with the content of cross-linking degree increasing. In a certain range, the responding capacity got stronger with the content of AA increasing.Finally, PAM-co-AA-NA-IPCs has a high specificity and sensitivity to NA molecule, and has a rapid response speed and good recoverability.