Preparation of monodisperse fluorescent core-shell polymer microspheres with functional groups in the shell layer by two-stage distillation-precipitation polymerization
Monodisperse crosslinked core-shell micrometer-sized microspheres bearing a brightly blue fluorescent dye, carbazole, and containing various functional groups in the shell layers were prepared by a two-stage distillation-precipitation polymerization in acetonitrile in the absence of any stabilizer. Commercial divinylbenzene (DVB), containing 80 vol.% of DVB, was polymerized by distillation-precipitation in acetonitrile without any stabilizer using 2,2'-azobisisobutyronitrile (AIBN) as the initiator for the first stage of polymerization which resulted in monodisperse polyDVB microspheres used as the core. Several functional monomers, including 2-hydroxyethyl methacrylate and acrylonitrile together with N-vinylcarbazole blue fluorescent comonomer, were incorporated into the shell layers with AIBN as initiator during the second stage of polymerization. The resultant core-shell polymer microspheres were characterized using scanning electron microscopy, Fourier transform infrared spectroscopy, UV-visible spectroscopy and fluorescence spectroscopy. (c) 2006 Society of Chemical Industry.