The dynamics of in-core perfluorinated alkyl pendants in microgel star polymers were investigated by F-19 nuclear magnetic resonance spectroscopy and F-19 spin spin, the efficient encapsulation of perfluorinated guests into the relaxation time (T-2) measurements, to elucidate the origin of, fluorous microgel cores. Fluorinated microgel star polymers were prepared by the linking reaction of chlorine-capped poly(methyl methacrylate) arms. with dimethacrylate linking agents and a perfluorinated methacrylate via ruthenium-catalyzed living radical polymerization. Temperature-depend-ent T-2 measurements revealed the reduced thermodynamic mobility of the perfluorinated pendants indicative of their accumulation and thus aggregation in the core network. Fluorinated Microgel star polymers accordingly provide stable "fluorous compartments" where he encapsulation of perfluoromethylcyclohexane (PFMCH) in DMF is-better attained and more efficient than that in the corresponding block,copolymer micelles.