Facile fabrication of double-shelled hollow microspheres via double in situ miniemulsion polymerization

We describe a facile and flexible technique for fabricating double-shelled hybrid hollow microspheres with a controlled void size via in situ miniemulsion polymerization. After monomers polymerize the tetraethoxysilane phase is compressed and restricted as a liquid core leading to the formation of a hollow structure and silica shell. Furthermore, magnetic hollow microspheres are obtained conveniently.