Fabrication of triple-shelled hollow spheres with optical properties via RAFT polymerization

The triple-shelled hollow spheres with optical properties were prepared via reversible addition-fragmentation chain transfer (RAFT) polymerization. After removal the core templates of the poly (styrene), the hollow silica spheres were obtained. The coating process of poly (methyl methacrylate) (PMMA) on the hollow silica spheres surface via surface RAFT polymerization was performed subsequently. The polymers coated on the hollow spheres surfaces were end-functionalized by trithiocarbonate , and they were used as RAFT agent to proceed the chain extension polymerization using Tb complex as monomer . The samples were characterized by FT-IR, SEM and luminescence spectroscopy respectively. The results indicated that the triple-shelled hollow spheres had been prepared successfully and the average diameter of the hollow core was about 1   μm.