Examination of Polysulfide Sealants by Scanning Electron Microscopy
Abstract
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 < 4 um. A technique was developed for the removal of the surface calcium carbonate exposing other solid additives. Amongst 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. Polysulfide sealants are used extensively in aircraft where there is a requirement for sealing metal joints and fasteners in integral fuel tanks, water tanks and canopies. The sealants are based on polysulfide polymers cured by the addition of a strong oxidizing agent. Australia
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1987
- Accession Number
- ADA192704
Entities
People
- V. M. Silva
- W. Mazurek
Organizations
- Defence Science and Technology Group