Preparation of poly(methyl methacrylate)-silica nanocomposites via DMP-assisted RAFT polymerization and NR/PMMA-RAFT-SiO2 hybrid membrane for pervaporation

Poly(methyl methacrylate)-silica (PMMA-RAFT-SiO2) nanocomposite emulsion was successfully synthesized via a combination of differential microemulsion polymerization (DMP) and reversible addition-fragmentation chain-transfer (RAFT) polymerization. The PMMA-RAFT-SiO2 emulsion with a low SiO2 loading (10 wt%) exhibited nano-sized particles (49 nm) with a core–shell structure and a high monomer conversion (88%). Natural rubber (NR) latex filled with PMMA-RAFT-SiO2 nanocomposites was cast to form hybrid membranes for pervaporation. The addition of SiO2 enhanced the physical properties of the composite membranes. The NR/PMMA-RAFT-SiO2 hybrid membrane with 4.0 wt% SiO2 content showed good mechanical properties. The hybrid membranes had hydrophilic properties and gave a high separation performance in the pervaporation of an ethanol solution (flux = 1,873–2,245 g/m2hr and pure water in permeate = 98–99%). Thus, the PMMA-RAFT-SiO2 nanocomposites had a great potential to be used as an effective filler in hybrid membranes for separation technology.