N. Shevchenkoa,b, A. Menshikova b, A. Yakimansky b, A. Sel'kinc, A. Bazhenova c, A. Bilibina
a Institute of Chemistry, Saint Petersburg State University, University Pr. 26, St. Petersburg, 198504 Russia, e-mail: firstname.lastname@example.org
b Institute of Macromolecular Compounds, RAS, Bolshoy Pr. 31, St. Petersburg, 199004 Russia, e-mail: email@example.com
c Ioffe Physico-Technical Institute, RAS, Politekhnicheskaya 26, St. Petersburg, 194021 Russia, e-mail: Alexander.Selkin@mail.ioffe.ru
There has been a great interest in monodisperse polymeric particles of submicron size as structural elements of photonic crystals (PC), since they are capable of self-assembling and forming close-packed three-dimensional ordered structures. It's expedient to obtain chromophore-containing PC for fine tuning of their optical characteristics. If a chromophore emits light of wave-length in the photonic band gap region, where electromagnetic waves can not propagate, PC could hide the emission. These polymeric PC could be used as good models for studding light interaction with crystal lattices. In the case of chromophore interaction with some vapours, emission spectra could be changed and PC could be applied as gas chemisensors.
Core-shell monodisperse particles including dye-containing comonomer units were prepared by styrene (St) and N-vinylformamide (VFA) emulsifier-free emulsion copolymerization using 2,2'-azobis[2-(2-imidazolin-2-yl) propane] dichloride as a cationic initiator. Some dye-containing methacrylic comonomers were added at the last step of the process along with a cross-linking agent. Besides, p-aminostyrene units were introduced in the surface layer of core-shell poly(St-co-VFA) particles, as aromatic amino groups were shown to be convenient for covalent chromophore binding on the particles surface. Luminescence and Bragg reflection spectra of PC fabricated from the both types of the particles proved a good promise for their application as chemisensors.
Authors are grateful to the Program «Organic and Hybride Nanostructured Materials for Photonics» of Presidium of the Russian Academy of Sciences for the financial support.