Ultrafine palladium nanoparticles confined in polydopamine functionalized chlorinated poly(vinyl chloride) nanofibers for Heck reaction

Abstract

AbstractPolydopamine has been considered as the adhesive of mussels to solid surfaces in biological systems. The development of dopamine and polydopamine functionalized nanofibrous materials is highly desirable for catalysis, drug delivery and tissue engineering. Polydopamine induced surface functionalized solid matrices have been proved to be efficient supporting materials for palladium nanoparticles. In this study, the dopamine monomers were first incorporated into the Pd2+/chlorated poly(vinyl chloride) (CPVC) composite nanofibers by electrospinning and then polymerized in basic and reductive solution at elevated temperature to prepare stable polydopamine functionalized CPVC supported palladium composite nanofibers. Scanning electron microscopy images show that uniform and smooth nanofibers with diameter of ~325 nm have been prepared and high temperature can promote their solvent resistance. Fourier transformed infrared and UV–visible (UV–Vis) spectra confirmed the synthesis of polydopamine inside the composite nanofibers. The ultrafine palladium nanoparticles inside the composite nanofibers were characterized by X‐ray spectroscopy and transmission electron microscopy. Although these palladium nanoparticles were confined inside the nanofibers, they exhibited excellent catalytic efficiency for the Heck reactions of aryl iodides with alkenes. Moreover, this novel fibrous catalyst could be easily recovered by simple filtration and reused at least five times without obviously loss of initial catalytic activity. In all, we have developed a distinctive way for the synthesis of polydopamine functionalized polymeric materials for catalysis and other applications.