Examination of Polysulfide Sealants by Scanning Electron Microscopy

摘要

A procedure was developed for the examination of polysulfide sealants by scanning electron microscopy. This procedure was applied to manganese dioxide and dichromate-cured elastomers. Calcium carbonate filler was identified in both types of sealants and the particle size was found to be less than 4 microns. A technique was developed for the removal of the surface calcium carbonate exposing other solid additives. Among these, manganese dioxide was most obvious due to the large particle size and abundance. The presence of chromium containing particles could not be established and in practical terms it can be considered as a solution in the polysulfide. This implies a homogeneous phase reaction between the dichromate curing agent and the prepolymer and consequently a greater likelihood of a more complete curing of the polymer than that effected by manganese dioxide.