Surface Modification of Nano-Silica with Silane Coupling Agent

Surface modification of nanoSiO 2 was carried out in ethanol solution with two different silane coupling agents, 3-aminopropyltriethoxysilane (KH-550) and 3-methacryloxypropyltrimethoxysilane (KH-570), respectively. The structure and performance of modified nanoSiO 2 were analyzed by infrared spectroscopy, surface hydroxyl number and conductivity. The influence factors as stirring time, temperature and modifier amount on modified performance have been discussed. The results shown that optimal modification conditions with KH-550 and KH-570 were as follow: temperature 75 o C, stirring time 4 h and the modifier 5% (w/w). Surface hydroxyl numbers were 0.7826×10 20 /g and 0.7525×10 20 /g, conductivity were 32μs/cm and 92μs/cm, respectively. The modification effect of nanoSiO 2 with KH-550 was better than KH-570.