Trioctyl Phosphate (TOP)

Catalog NumberACM78422-2

CAS Number78-42-2

CategoryPhosphate Ester Flame Retardant

Synonyms	Trioctyl phosphate (TOP)
Molecular Formula	C36H75O4P
Purity	≥ 99%
Appearance	colorless transparent liquid
Application	The product is mainly used as a solvent for the production of hydrogen peroxide by anthraquinone method. It can also be used as a cold resistant, flame retardant and plasticizer for vinyl resin, cellulose resin and synthetic rubber.
Acid Value	Max 0.1 (mgKOH/g)
APHA Color	≤ 20
Packaging	Net weight 180kg / barrel or 900kg / IBC.

Download COA Download MSDS

Case Study

Enhancing Polylactide Foam with Trioctyl Phosphate and Bio-Based Additives

Suparanon, Tunsuda, et al. International Journal of Biological Macromolecules 282 (2024): 136684.

This study examined the use of Trioctyl Phosphate (TOP) as a multifunctional additive to improve the flame retardancy and mechanical performance of polylactide (PLA) foam, while also exploring a sustainable strategy to reduce reliance on conventional chemical additives.
Development and Methodology: To address the inherent flammability and brittleness of PLA foam, TOP was incorporated via melt extrusion. Its performance as a commercial flame retardant (CFR) and plasticizer was evaluated. Subsequently, to mitigate environmental and health concerns associated with TOP, a portion was replaced with bio-based flame retardants (BFRs) derived from agricultural waste, specifically pumpkin shell powder (PK). Formulations with varying TOP-to-BFR ratios were tested for crystallization behavior, impact strength, and fire safety.
Key Performance: TOP proved to be a highly effective additive. A PLA foam containing 10 phr of TOP exhibited enhanced crystallization, excellent flame retardancy, and significantly improved impact strength. An optimized hybrid formulation, using a combination of 7.5 phr TOP and 2.5 phr PK, achieved the critical UL-94 V-0 rating and increased impact strength by approximately 84% compared to neat PLA foam. This synergy allows for a reduced TOP loading while maintaining superior performance.
Mechanism: TOP functions as both a flame retardant and an impact modifier for PLA. When combined with PK, the system works through a synergistic mechanism: TOP contributes to gas-phase flame inhibition and plasticization, while the silicate and carbonaceous components from PK promote the formation of a stable, insulating char in the condensed phase.

Enhancing Selective Extraction of Germanium(IV) with Trioctyl Phosphate as Modifier

Zhang, Tao, et al. Minerals Engineering 136 (2019): 155-160.

Besides being used as a flame retardant, Trioctyl Phosphate (TOP) also acts as a high-selectivity modifier in solvent extraction systems, suppressing As(III) co-extraction while promoting Ge(IV) recovery from sulfuric acid leachates of secondary zinc oxide, addressing the key separation challenge in hydrometallurgy.
Composite Fabrication Process: The organic phase was prepared by mixing 25%(v/v) tertiary amine (N235), 10%(v/v) TOP, and sulfonated kerosene, then acidified with 70g/L H2SO4. The aqueous phase (pH=1.2) contained Ge(IV), Zn(II), As(III), and other impurities, with tartaric acid added at a 5:1 molar ratio to Ge(IV) as a complexant. Extraction was conducted at 25℃ for 10.5min (O/A=1/1), followed by stripping with 0.5mol/L NaOH (O/A=1/1, 10min).
Performance Evaluation: TOP's steric hindrance inhibited As(III) co-extraction (only 1.3% extracted) while Ge(IV) extraction reached 93.9%. Zn(II), Fe(III), and Cd(II) extractions were negligible. Five-stage countercurrent extraction reduced raffinate Ge(IV) to <1.5mg/L. NaOH stripping achieved 100% recovery of both Ge(IV) and As(III), making the system efficient for germanium separation in zinc hydrometallurgical processes.

If the product of interest is not available in our catalog, please contact us to see if there is any relevant stock or other purchase channels.