Visualization of filler network in silicone rubber with confocal laser-scanning microscopy

Most of the present studies of filler network structure basically stay in some phenomenological descriptions and classical electron microscopes are restricted by conventional 2-D imaging. This paper completed the visualization of filler networks in silica-reinforced silicone rubber (MVQ). Using a special network visualization technique based on fluorescent markers embedded in silica and Confocal Laser-Scanning Microscopy with an optical lateral resolution of about 200 nm, insights into the precise 3-D morphology and detailed micro-structure of filler networks were gained. A kind of sensitized-silica phosphor was prepared, with the excitation wavelength of 405 nm, which is consistent with the laser wavelength of Confocal Laser-Scanning Microscopy. Combining Image J software and tensile measurements, shapes, network structures, size distributions of aggregates in the silicone rubber matrix with silica loading from 10 to 60 phr were directly observed and the loading threshold for the formation of filler network in this experiment was obtained.