Journal of Colloid and Interface Science, Vol.386, 167-173, 2012
Preparation and characterization of composites built of poly(N-benzophenoyl methacrylamide-co-N-hydroxyethyl acrylamide) cores and silica raspberry-like shells with dual orthogonal functionality
The design and fabrication of novel poly(N-benzophenoyl methacrylamide-co-N-hydroxyethyl acrylamide)@SiO2 composites are reported herein. These core-shell composites demonstrate orthogonal functionality, composed of photoreactive cores, containing a benzophenone (BPh) moiety and silica (SiO2) shells, enabling the utilization of the free hydroxyl groups via silane-based chemistry. The co-polymer cores, which are 1.28 mu m in diameter, are first obtained by dispersion polymerization of photoreactive (N-benzophenoyl methacrylamide) (BPMA) and N-Hydroxyethyl acrylamide (HEAA). Next, silica seeds with a 42 nm diameter are deposited onto the surfaces as a result of the hydrolysis and the condensation of tetraethyl orthosilicate (TEOS) in a basic condition. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), FT-infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), UV-spectrophotometry, X-ray photoelectron spectroscopy (XPS), and zeta-potential measurements were used to characterize the composites. The morphology and surface smoothness of the deposited silica nanopartides (NPs) were found to strongly depend on a number of parameters such as the pH value of the medium, TEOS concentration, and the temperature. (c) 2012 Elsevier Inc. All rights reserved.
Keywords:Core-shell materials;Raspberry-like composites;Photochemistry;Co-polymer;Silica nanoparticles