Polysulfide sealants resist fuel, oils, chemicals and standing water better than most elastomers, so they go into airfield pavements, fuel farms, water tanks, swimming pools and the secondary seal of insulating glass units. They give off a distinctive sulfur smell while curing. On ordinary facades, silicones and urethanes are the usual choice.
Fuel-resistant joints on the apron are polysulfide, check the mix ratio on every batch.
Also heard as
- Thiokol
- PS sealant
Related terms
Sealant
A material that fills a joint or gap to stop water and air, while accommodating movement.
Polyurethane sealant
A tough, paintable elastomeric sealant used widely on concrete, masonry and traffic joints.
Reversion
Cured sealant breaking down and turning soft, sticky or gooey again with heat, sun or chemical attack.
Movement capability
How far a sealant can stretch and compress, as a percentage of joint width, while keeping its seal.