Abstract
Poly-methylmetacrylate (PMMA) is mainly applied in the plastic manufacturing industry, but PMMA is weak and gradually got discolor. The strength of PMMA can be improved through organic-inorganic hybrid nano composites with inorganic nano particles such as, $SiO_2$ or ZrO. However, inorganic nano particles are mostly agglomerated spontaneously. In this study, the zeta potential is controlled using different types of organic solvent with different concentrations, dispersibillity of $SiO_2$ nano particles on the PMMA particle are analyzed. When 3 M acetic acid is used, absolute value of the zeta potential is higher, $SiO_2$ nano particle is well attached, and dispersed on the PMMA particle surface. Results indicate that the absolute value of the zeta potential affects the stability of $SiO_2$ dispersion.