Tris(Hydroxymethyl) Phosphine Oxide (THPO)

Chemical formula:


Molecular weight:



Colorless or pale yellow liquid


As new reactive organic phosphorus flame retardant, THPO has a high phosphorus content(≥20.8), contains an active hydroxymethyl, is excellent at Hydrolysis resistance. It can be used for the production of polyether polyols as initiator, or as an additive to Polyether polyols then react with MDI. Polyether polyols made from THPO haslow smoke, low toxicity, high carbon residue, and good compatibility, which could be used in polyurethane foam to increase the oxygen index to 30 more, flame retardant rating to UL94- V-0 level and the combustion heat release rate is slow. THPO is a stable and long lasting flame retardant, it does not affect the mechanical properties of the material. so it can be used in rigid polyurethane foam of refrigerators, freezers, cold storage, building facades and so on.THPO containing an active methylol group, phosphorus-containing flame retardants may be used as synthetic intermediates.

Packaging and storage:

In 250kg drum, sealed in plastic drums. Store in cool, dry and well ventilated area.