Polymer-assisted spray drying method for BaTiO₃ particles having single-layer coverage with Fe₃O₄ particles

Abstract

An integrated approach using anionic polymer sources and conventional spray drying technology was proposed to synthesize inorganic particles covered with single layer of fine particles. Negatively charged poly(acrylic acid) adsorbed on the two particles even though the particles had negative charge and assisted to disperse them individually in suspension. The dispersed 0.25 µm Fe₃O₄ was uniformly accumulated with single layer on 2.0 µm BaTiO₃ particles by their condensation in shrinking sprayed droplets. The poly(acrylic acid) molecules which adsorbed on both particles had a function to bind the two particles, and the Fe₃O₄ fine particles were fixed on BaTiO₃ particles persistently and discretely. The poly(acrylic acid)-assisted spray drying method is applicable for any combination of various functional particles.