A facile process for generating monolithic-structured nano-silica/polystyrene multi-core/shell microspheres by a seeded sol–gel process method

Monodisperse “monolithic-structured” organic–inorganic composite microspheres were produced by a seeded sol–gel process method. A large number of nano-silica particles were generated and dispersed in the inner domains of the obtained microspheres. Seed particles were prepared by dispersion co-polymerization of styrene and (trimethoxysilyl)propyl 2-methylprop-2-enoate (TMSPM). The seed particles were swollen with an emulsified tetraethoxysilane (TEOS) in 0.25 wt.% sodium dodecylsulfate (SDS) aqueous solutions. Then the sol–gel reaction was conducted with ammonium hydroxide after completion of the swelling process. In contrast to conventional methods, the sol–gel reaction occurred in the inner space of the prepared template particles and monolithic-structured nano-silica and polystyrene organic–inorganic composite microspheres were obtained. The synthetic procedure for composite particles was studied by utilizing transmission electron microscopy (TEM), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), and thermo-gravimetric analysis (TGA).

We present a facile method to produce “monolithic-structured” nano-silica/polystyrene composite microspheres through a seeded sol–gel process. The emulsified silanol precursor was swollen into the seed particles and generating nano-sized silica particles with silica walls as part of composite particles. In addition, hollow silica particles were able to obtain after calcination at 550 °C for 30 min.Figure optionsDownload high-quality image (95 K)Download as PowerPoint slideResearch highlights
► A seeded sol–gel process: sol–gel reaction in the inner domains of seed particles.
► A number of silica nanoparticles were generated in the composite particles.
► Silica walls were generated by the seeded sol–gel reaction method.
► Hollow particles were obtained after calcinations of composite particles.