Triethylenediamine (1,4-diazabicyclo[2.2.2]octane)
Triethylenediamine, widely known by the trade name DABCO, is the reference tertiary amine catalyst for the isocyanate–polyol (gelling) reaction in polyurethanes.
TEDA is 1,4-diazabicyclo[2.2.2]octane: a compact, cage-shaped molecule with two tertiary nitrogens (molecular weight 112.17 g/mol). It is a white, hygroscopic crystalline solid that melts at about 156–159 °C and sublimes readily. Because it is a solid, it is often supplied as a solution, for example 33% in dipropylene glycol.
TEDA catalyzes polyurethane formation in foams, elastomers, coatings, adhesives and sealants. It is often combined with a blowing catalyst and with metal catalysts such as tin or bismuth compounds to balance gel time, cure speed and surface cure.
TEDA is a flammable solid, harmful if swallowed and can cause serious eye damage. Like other volatile tertiary amines, its vapor can cause temporary hazy or “blue-halo” vision (glaucopsia). Use ventilation and eye protection, keep containers closed, store dry and away from ignition sources, and follow the SDS.
Gelling catalysts mainly speed up the isocyanate–polyol reaction that builds the polymer. Blowing catalysts mainly speed up the isocyanate–water reaction that makes CO₂. TEDA is primarily a gelling catalyst.
It is a solid that sublimes, so dissolving it in a glycol makes it easy to meter and blend into the polyol side.
Temporary blurred, hazy or blue-halo vision caused by exposure to volatile amine vapors. It usually resolves after exposure stops, but it is a sign that ventilation is inadequate.
