Preparation and humidity controlling behaviors of sepiolite/polyacrylic acid (sodium) composite

Sepiolite/polyacrylic acid (sodium) nanocomposite was synthesized using inverse suspension polymerization method under different sepiolite content, dispersant content and neutralization degree with orthogonal experiments. The surface morphology and structure of sepiolite/polyacrylic acid composite were observed and analyzed, and the humidity controlling properties of composites were determined by absorption and desorption testing. The results showed that sepiolite/polyacrylic acid composite was in a fine particle with rough surface. During the polymerization process, acrylic acid monomer was grafted with hydroxyl on the surface of sepiolite and then intercalated successfully into the tetrahedral silica layers of sepiolite. With the increasing of sepiolite content, dispersant conten, neutralization degree and the humidity controlling behaviors of composite rose initially and then dropped down. The impact of three factors on the humidity controlling behavior of composites increased by the order of sepiolite content, dispersant content and neutralization degree. The optimum preparation parameters are sepiolite content of 4%, dispersant content of 15% and neutralization degree of 90%.