M. A. Rahman

Synthesis of γ-Alumina Particles and Surface Characterization

Alumina was synthesized via sol-gel technique by the hydrolysis of aluminium ion controlled by urea in aque- ous media. The resulting sol composed of Al(OH)3 particles coalesced and became a transparent gel. The freshly prepared gel was heated at 280°C to obtain alumina particles. The obtained particles were found to be amorphous � - alumina parti- cles with high porosity, characterized by FTIR, XRD and SBET techniques. Electron micrograph shows that the particles are nano-sized having non-spherical shape. Comparatively higher magnitude of adsorption of cationic surfactant indicated that the surface of alumina particles is negatively charged.

Carboxyl functionalized poly(methyl methacrylate-acrylic acid-ethylene glycol dimethacrylate) copolymer particles and their amination with amine-nucleophiles

Abstract Poly(methyl methacrylate-acrylic acid-ethylene glycol dimethacrylate) copolymer particles abbreviated as P(MMA-AA-EGDM) copolymer particles were prepared by soap-free emulsion copolymerization. The concentration of carboxyl group on/near the surface of particles increased with the increase in acrylic acid (AA) content in the recipe. The carboxyl groups were reacted with amine nucleophiles such ethylene diamine and 1,6-diaminohexane through preactivation with dicyclohexyl carbodiimide as a coupling agent. The modified particles were characterized by electron micrographs and FTIR spectral analysis. Adsorption behaviours of some biomolecules were measured to have idea about=-0 the polarity of the particles surface