Preparation of nano-silica reinforced silicone rubber membranes for sample inlet of ion mobility spectrometers

Surface hydrophobization modification of nano-silica was conducted in liquid phase with hexamethyldisilazane as modifier, and the modified nano-silica reinforced silicone rubber membranes were prepared for sample inlet of ion mobility spectrometer. Effect of heating temperature and reaction time on the modification of nano-silica was studied. And compatibility of modified nano-silica and silicone rubber, thickness and tensile properties of nano-silica reinforced silicone rubber membranes were investigated. The results showed that the surface hydroxyl number and specific surface area of nano-silica decreased with increasing the heating temperature or extending the reaction time, and the optimum heating temperature and reaction time were 120 degree C and 4 h. With extending reaction time, transmittance of mixed solution of modified nano-silica and silicone rubber increased, showing that compatibility of nano-silica and silicone rubber was improved. Silicone rubber membranes were fabricated with polystyrene as t