Flame Retardants
REACH
Triphenyl phosphate
CAS Number
115-86-6
EC Number
204-112-2
What is Triphenyl phosphate?
Triphenyl phosphate (CAS 115-86-6), abbreviated TPP, is an organophosphate ester used commercially as a flame retardant and plasticizer.
Where is Triphenyl phosphate used?
- Plastics and polymer compounding: incorporated into cellulose acetate and PVC
- Engineering resins: meets UL 94 flammability standards while improving flexibility
- Electronics: flame-retardant additive in circuit board laminates and connector housings
- Encapsulant resins: thermal stability under load is a qualification requirement
- Lubricants: added to hydraulic fluids and gear oils where fire-resistant performance is specified
- Construction: treats rigid foam insulation and sealant formulations requiring passive fire protection
- It releases phosphoric acid derivatives during combustion, interrupting the flame cycle without halogenated chemistry.
Good to know: Technical grade is standard; high-purity grades serve electronics and aerospace uses where trace impurity limits are tightly controlled.
Commercial specifications
- Purity grades typically 98% to 99%+
Other Names (Synonyms)
triphenyl ester of phosphoric acid|Triphenoxyphosphine oxide|Phosphoric acid, triphenyl ester|TPP|phenyl phosphate|Disflamoll TP|Celluflex TPP|Phosflex TPP
What are the physical properties of Triphenyl phosphate?
Melting Point 49-50 °C
Boiling Point 370 °C
Density 1.2055 g/cm³ @ Temp: 50 °C
Flash Point 435 °F
Appearance Colorless, crystalline powder; odorless. Soluble in most lacquers, solvents, thinners, oils; insoluble in water. Combustible.
Color White
Odor Odorless
Form Crystalline Flakes
Water Solubility insoluble
Vapor Pressure 1.3 mm Hg ( 200 °C)
Refractive Index 1.563
Log P 4.6 at 20℃
How is Triphenyl phosphate classified and handled safely? Learn More
Warning
GHS09· Environmental Hazard
Hazard Statements
H400 Very toxic to aquatic life [Warning Hazardous to the aquatic environment, acute hazard]
H411 Toxic to aquatic life with long lasting effects [Hazardous to the aquatic environment, long-term hazard]
H303 May be harmful if swallowed [Warning Acute toxicity, oral]
H320 Causes eye irritation [Warning Serious eye damage/eye irritation]
H410 Very toxic to aquatic life with long lasting effects [Warning Hazardous to the aquatic environment, long-term hazard]
Which trade and regulatory codes apply to Triphenyl phosphate?
HS Code 29190010
UN Number 3077
ADR Class 9
Packing Group III
Storage Class 11 - Combustible Solids
WGK (Germany) 2