Epoxy resins usually are considered to be brittle systems and not applicable to many sealant applications. However, the use of reactive flexibilizers such as polyamide and polysulfide, and others can make epoxy sealants useful as bridge sealants, masonry adhesives, and monolithic heavy-duty coating.
RESULTING PROPERTIES
The compositions are resistant to many nonoxidizing acids, salts and alkalines. A typical formulation for a corrosion resistant epoxy sealant is shown above. Epoxy sealants are considered to be low performance sealants due to their rigidity, and they have a relatively high cost compared to other sealants in this classification. Thus, epoxy sealants are only employed where their chemical or heat resistance is of benefit.
Most epoxy sealant or caulk systems are limited to +/-5% movement. The main advantage of an epoxy sealant is its high degree of adhesion. They are also easy to handle, have low shrinkage being 100% solids systems, and have good overall environmental and chemical resistance.
These sealants are used in the construction, electrical, and transportation industries. They find diverse applications such as adhesives for various substrates, in crack repair for concrete, as grouting material, and as an automotive body solder.
