Preparation and properties of polyimide/silica hybrid nanocomposites

Abstract In this study, a commercially available nano‐sized silica (SiO 2 ) was surface‐modified via esterification with oleic acid (OA), a relatively inexpensive and hydrophobic modifier. The surface‐modified silica (SiO 2 ‐OA) nanoparticles were used to disperse in the poly(amic acid) solutions of a commercial polyimide (PI), used for two‐layer film, and thermally imidized to form a series of PI/silica nanocomposites. The effects of the addition of SiO 2 ‐OA nanoparticles on the properties of the as‐prepared PI/silica nanocomposites were studied. The results indicated that the as‐prepared PI/silica nanocomposites exhibited improvements in the dynamic mechanical property, thermal stability, water resistance, and thermal expansion. POLYM. COMPOS. 28:575–581, 2007. © 2007 Society of Plastics Engineers