Typical Formulation Ingredients
Phase
Ingredient
Parts by weight
A
Polysulfide polymer (Thiokol LP-32, Toray)
A
Plasticizers (e.g., dibutyl phthalate)
A
Rutile titanium dioxide
A
Adhesive resin (e.g., epoxy)
A
Organosilane (Dynasylan GLMO, Evonik)
A
Fumed silica (Aerosil R 202, Evonik)
Resulting Properties
Polysulfide adhesives and sealants are formulated using base polymer, curing agents, reinforcing fillers, plasticizers, and adhesion additives.
Compounded products are significantly different because various curing systems and application properties are designed into the products to meet the needs of the specified application. The table above defines several types of polysulfide sealant formulations and applications.
Polysulfide adhesives and sealants have been successful in applications requiring:
-
Good moisture
-
Solvent and ozone resistance
-
Good weathering
-
Low temperature properties
However, the chemical linkages that provide these properties also contribute to poor high temperature stability and high compression set because of stress relaxation.