Triethyl Phosphate: Properties, Uses in Plastics and Regulatory Status

Triethyl phosphate (TEP, CAS 78-40-0) is an alkyl phosphate ester used as a halogen-free liquid flame retardant and viscosity reducer in rigid polyurethane and polyisocyanurate (PIR) insulation foam and in unsaturated polyester resins. With six carbons and one phosphorus atom on a molecular weight of 182.15 g/mol, TEP carries about 17 % phosphorus by weight, less than DMMP and almost twice TCPP, which raises the question of why formulators choose it at all.

TEP is registered under REACH, is not on the REACH Candidate List, and its harmonised CLP entry (index 015-013-00-7) covers acute oral toxicity only, as Acute Tox. 4* H302. The answer to the question of choice is its second job: TEP thins the polyol or the resin it flame-retards, a combination that sets it apart among plastic additives. TEP is one of the flame-retardant substances in our database of plastic additives, each recorded with the same identity, dosage and regulatory fields.

This page covers the identity and the phosphonate and phosphite naming traps, the flame-retardant and viscosity roles, the PubChem constants, the 3 plastics systems, the 5 fire-test standards, the packages TEP works in, a regulatory matrix dated 24 October 2026, the comparison with DMMP, TCPP, DMPP and expandable graphite, and sourcing.

Table T1. Triethyl phosphate identity card.

Footnote: identity and physical data from PubChem CID 6535 and ECHA substance 100.001.013. The phosphorus content is calculated from the molecular formula (30.97 ÷ 182.15), not taken from a supplier data sheet. Status 24 October 2026.

What Is Triethyl Phosphate (TEP)?#

Triethyl phosphate is the triethyl ester of phosphoric acid: a phosphorus atom double-bonded to one oxygen and linked through three more oxygens to three ethyl groups, which makes it an alkyl phosphate ester and an additive, not a reactive, flame retardant. The formula C6H15O4P at 182.15 g/mol confirms the name: six carbons in three ethyl groups, four oxygens and one phosphorus atom, with no aromatic ring and no halogen. Which substance, then, does the abbreviation TEP name on a polyol data sheet? In a plastics context it names one substance, CAS 78-40-0, inside one functional class, the phosphorus flame retardants.

An additive flame retardant is blended into the polymer and not chemically bound to it, unlike a reactive one built into the polymer backbone, a distinction that governs the migration question answered below the contextual border. Within the family, TEP is the alkyl member of the organophosphate group, beside aryl phosphates such as triphenyl phosphate and chlorinated phosphates such as TCPP. The 13 chemical types of flame retardants, from mineral fillers to phosphate esters, are compared on the hub for flame retardants for plastics, where TEP sits in the organophosphate group.

What does TEP stand for, and what are its other names?#

TEP stands for triethyl phosphate, and the same liquid appears in catalogues as phosphoric acid triethyl ester and in formulae as Et3PO4, all under CAS number 78-40-0 and EC number 201-114-5. A data sheet that prints any other CAS number under this name is wrong, and at least one ranking product page prints 78-40-2, so the CAS number is the field to check first. No trade name for TEP is recorded in our source library.

Is triethyl phosphate a phosphate or a phosphonate?#

Triethyl phosphate is a phosphate ester, not a phosphonate: all three ethyl groups are attached to phosphorus through oxygen, whereas a phosphonate such as DMMP bonds one carbon directly to phosphorus. The formulae show it as an oxygen count: TEP (C6H15O4P) carries four oxygens and three P-O-C ester arms, DMMP (C3H9O3P) three oxygens and one P-C bond. The consequence is phosphorus per kilogram: DMMP carries about 25 % and TEP about 17 %, both derived from the formula.

The distinction matters because at least two secondary sources group TEP with the phosphonates, and the class decides where a specification places the substance. TEP belongs with the aryl, alkyl and chlorinated phosphate esters, which are compared as a class on organophosphate flame retardants (phosphate esters).

Triethyl phosphate vs triethyl phosphite: which one is meant?#

Triethyl phosphite is a different substance from triethyl phosphate: a phosphite ester has one oxygen fewer around phosphorus, exactly as triphenyl phosphite (C18H15O3P) differs from triphenyl phosphate (C18H15O4P). One oxygen fewer means a different substance, a different CAS number and a different function in a plastic.

Phosphites in plastics are stabilizers, secondary antioxidants and PVC co-stabilizers, while phosphates are flame retardants and plasticizers, so a quotation or a price index for the phosphite says nothing about TEP. How a phosphite works as a PVC co-stabilizer is set out on triphenyl phosphite.

Is triethyl phosphate a halogen-free flame retardant?#

Yes: triethyl phosphate contains carbon, hydrogen, oxygen and phosphorus only, so it is halogen-free, unlike the chlorinated phosphate TCPP that carries 32.5 % chlorine in the same foams.

Halogen-free does not mean hazard-free; the hazard section sets out TEP's classification. Liquid phosphorus esters sit beside the mineral, nitrogen and intumescent routes among halogen-free flame retardants.

How Does Triethyl Phosphate Work as a Flame Retardant?#

Triethyl phosphate delivers phosphorus into a foam or resin, and phosphorus flame retardants act in two places at once: in the condensed phase they promote char and a phosphate glass, and in the gas phase they inhibit the flame. TEP supplies that phosphorus at about 17 wt% of its own weight, as a small liquid molecule.

Bernhard Schartel at the German Federal Institute for Materials Research and Testing (BAM) grouped phosphorus action into condensed-phase modes and a gas-phase mode in a 2010 review in Materials. Red phosphorus, phosphinates, ammonium polyphosphate and the phosphate esters are compared under phosphorus flame retardants.

Phosphorus flame retardants act in 3 condensed-phase ways and 1 gas-phase way, listed below.

• Charring: the polymer converted into a carbon-rich residue that shields what lies underneath.
• Intumescence: that char swollen into an insulating layer.
• Inorganic phosphate glass: a non-volatile barrier over the burning surface.
• Gas-phase flame inhibition: lower combustion efficiency in the flame and a higher CO yield.

Which route dominates for TEP? Our source library holds no measured split for triethyl phosphate, so the list belongs to the family, and the one bearing property, a boiling point of 215 °C (419 °F), is not turned into a percentage.

The condensed-phase routes act on the burning surface and the gas-phase route in the flame, two answers to how flame retardants work set out step by step under how flame retardants work.

Why is TEP also used as a viscosity reducer?#

Triethyl phosphate is used as a viscosity reducer because it is a thin, low-molecular-weight liquid that is added to the polyol side of a polyurethane system or to an unsaturated polyester resin anyway, so the same additive that brings phosphorus also lowers the viscosity of the blend. One additive does two jobs, and that double role separates TEP from the other flame retardants on this page.

Solid flame retardants such as ammonium polyphosphate and expandable graphite add particles to the same blend instead. For scale, TCPP has a viscosity of 72 mPa·s at 25 °C (77 °F) in ICL's Fyrol PCF data; no viscosity value for TEP is recorded in our source library, so the thinning is stated as a function, not a number. TCEP, now an SVHC, was recorded in the same double role of flame-retardant plasticizer and viscosity regulator.

What Are the Physical and Chemical Properties of Triethyl Phosphate?#

Triethyl phosphate is a colourless liquid with a melting point of -56.5 °C (-69.7 °F), a boiling point of 215 °C (419 °F) and a density of 1.072 g/cm3. Table T2 lists the constants recorded for TEP in PubChem CID 6535, with the derived phosphorus content added.

Table T2. Physical and chemical properties of triethyl phosphate.

Footnote: the °F values are arithmetic conversions of the °C values. Status 24 October 2026.

The number a formulator reads first is the boiling point: at 215 °C (419 °F) TEP boils 34 °C (61.2 °F) above DMMP at 181 °C (357.8 °F), the same gap the DMMP record states. The phosphorus content of about 17 wt% is calculated from the formula, 30.97 g/mol of phosphorus in 182.15 g/mol.

Our source library holds no flash point, water solubility, vapour pressure or viscosity for TEP, so Table T2 omits those rows and the triethyl phosphate water solubility question stays open.

Which Polymers Use Triethyl Phosphate, and at What Dosage?#

Triethyl phosphate is used in 3 polymer systems: rigid polyurethane and polyisocyanurate foam and unsaturated polyester resins, where it is a liquid flame retardant and viscosity reducer, and cellulose acetate, where it is a solvent and plasticizer.

Table T3 sets each polymer system against the role of TEP and the loading verified in our source library, with two labelled comparators.

Table T3. Polymer systems that use triethyl phosphate.

Footnote: "not recorded" describes the evidence held, not the substance. Status 24 October 2026.

Our source library holds no verified loading for TEP in any of these polymer systems. The closest verified figure, about 15 wt% in polyurethane in the ECHA plastic additives initiative mapping, belongs to the phosphonate DMPP and says nothing about the TEP level a foam needs. Stored loadings for other flame retardants, polymer by polymer, are searchable in the flame retardant selector by polymer.

How would a TEP level arrive when a recipe gives one? Polyurethane recipes are written in parts per hundred polyol (pphp), not wt% of the finished foam; no TEP value in pphp is recorded here.

TEP in rigid PU and PIR insulation foam#

Rigid polyurethane and polyisocyanurate (PIR) insulation foam is the first of the 3 plastics systems recorded for triethyl phosphate, which goes into the polyol side as one of 5 flame-retardant options beside TCPP, DMMP, expandable graphite and reactive phosphorus polyols. On the polyol side TEP supplies phosphorus and thins the blend before it meets the isocyanate. Catalysts, blowing agents and surfactants, the rest of the rigid-foam recipe, are covered on additives for polyurethane and TPU.

A 2026 study in Materials (vol. 19, article 525) made PIR foam at an isocyanate index of 250 to 300, catalysed by DABCO TMR-2 with potassium octoate, and PUR foam at an index of 100 to 110 with PMDETA and Polycat 5, both blown with n-pentane and both made flame-retardant with TEP. Our source library records no TEP loading or fire result from that study, so none is quoted, and the catalysts and n-pentane appear only as recipe context.

TEP in unsaturated polyester resins#

In unsaturated polyester resins, triethyl phosphate is a liquid phosphorus flame retardant that also thins the resin, while the mineral route in the same composites, aluminium trihydrate, is used at high loadings. Unsaturated polyester composites for rail interiors are qualified to EN 45545-2 hazard levels HL2 and HL3, and the 3 flame-retardant routes recorded for them are aluminum trihydrate (ATH) at high loadings, ammonium polyphosphate, and the liquid phosphorus esters TEP and DMMP. No laminate build, glass content, TEP loading or hazard-level result for TEP is recorded in our source library, so the liquid route is described by its function: phosphorus delivered in a form that also lowers resin viscosity.

TEP as a solvent and plasticizer for cellulose acetate#

In cellulose acetate, triethyl phosphate is used as a solvent and a plasticizer, the third plastics use our source library records for it and the one where it belongs to the phosphate ester plasticizers rather than to the flame retardants. Its aryl relatives do the same kind of job in cellulosics: triphenyl phosphate is used in cellulose acetate film, and tricresyl phosphate is a flame-retardant plasticizer for cellulosics and PVC. No TEP dosage or film property for cellulose acetate is recorded here, and phosphate esters as a plasticizer class are compared under phosphate ester plasticizers.

What Is Triethyl Phosphate Used For in Plastics?#

Triethyl phosphate is used for 4 jobs in plastics, two of them in the same formulation. The 4 jobs are listed below.

• Flame retardant for rigid PU and PIR insulation foam: a halogen-free liquid in the polyol blend.
• Flame retardant for unsaturated polyester composites: a liquid phosphorus route beside ATH and ammonium polyphosphate.
• Viscosity reducer: in the same polyol blend or resin it flame-retards, the double role that defines the substance.
• Solvent and plasticizer for cellulose acetate: the plasticizer side of the phosphate ester.

Uses outside plastics are named in one supplementary section further down. Foam is where the first and third jobs meet, and plastic foams such as EPS, XPS, PU and PE foam each need a different package, compared under additives for plastic foams.

How Does Triethyl Phosphate Affect Fire Performance, and How Is It Measured?#

Four methods decide whether a TEP-containing foam or resin performs: the limiting oxygen index, the UL 94 burning test, the cone calorimeter and the reaction-to-fire classes of EN 13501-1 for building products and EN 45545-2 for rail. Each measures a different property, so a pass on one says nothing about the others.

Limiting oxygen index results are reported in vol % O2 under ISO 4589-2 and ASTM D2863-23e1, and the method and the values of common plastics are set out under limiting oxygen index (LOI).

Table T4 lists the 5 fire-test standards that apply to TEP's polymer systems, their units and the TEP values held in our source library.

Table T4. Fire-test methods for TEP-containing foams and resins.

Rigid foam is a cellular material, so its UL 94 result falls in the HF classes, and a rating means nothing without its thickness. The HF classes and their place among the UL 94 flammability ratings are explained on the test page.

No TEP result for any of the 5 standards is recorded in our source library, so the TEP column of Table T4 is empty by design, and values measured on DMMP or TCPP are not carried over.

How Does TEP Interact with Other Flame Retardants and Additives?#

TEP is normally one component of a flame-retardant package: in rigid foam it is combined with the chlorinated phosphate TCPP or with solid partners such as expandable graphite, and in unsaturated polyester with aluminium trihydrate or ammonium polyphosphate. The solid acid source used with liquid phosphorus in PU foam and polyester is ammonium polyphosphate, whose phase II decomposes from about 240 °C (464 °F).

The 3 partner types used with TEP are listed below.

• Chlorinated phosphates: TCPP, with TEP as the extra-phosphorus liquid.
• Solid intumescents and acid sources: expandable graphite and ammonium polyphosphate.
• Mineral fillers in resins: ATH at high loadings in unsaturated polyester.

The partners cover neighbouring temperature windows: the solids act from about 200 °C (392 °F) and 240 °C (464 °F), and TEP boils at 215 °C (419 °F). No measured synergy between TEP and expandable graphite or ammonium polyphosphate is recorded in our source library, so none is claimed. Rigid and flexible foam packages are compared in full under flame retardants for polyurethane foam.

What Is the Regulatory Status of Triethyl Phosphate?#

Triethyl phosphate is registered under REACH, is not a Substance of Very High Concern, and carries a harmonised CLP classification for acute oral toxicity only, Acute Tox. 4 H302; no restriction on it is recorded in our source library (status 24 October 2026).*

Table T5 sets out the regulatory position of TEP, instrument by instrument, with the date or reference behind each cell.

Table T5. Triethyl phosphate regulatory matrix, status 24 October 2026.

Footnote: "being verified" means our source library holds no record for this cell yet; it does not mean the substance is unregulated. "Not listed" and "not named" are stated only where a dated official list was checked.

Plastic additive regulations run in layers, and TEP's position differs by layer: a harmonised classification under CLP, a registration under REACH, a category rule in California and open cells elsewhere. How REACH, CLP, food-contact and US rules fit together is mapped under plastic additive regulations.

The direction of travel is set by the family. ECHA's flame-retardant regulatory strategy of March 2023 found that aliphatic brominated and organophosphorus flame retardants need more data, and according to industry reporting the organophosphorus investigation reports in December 2026 and December 2027. Whether that investigation covers TEP is not recorded in our source library.

Is triethyl phosphate an SVHC or restricted under REACH?#

No, triethyl phosphate is not a Substance of Very High Concern: it is absent from the REACH Candidate List, which held 253 entries at its last update of 4 February 2026, while two other phosphate esters, TCEP since 13 January 2010 and triphenyl phosphate since 7 November 2024, are on it. The absence was re-checked on the ECHA CHEM obligation list on 24 October 2026. HBCD (28 October 2008) and DBDPE (5 November 2025) are among its other flame retardants, and every plastic additive on the SVHC Candidate List carries its inclusion date there.

A foam or laminate containing TEP above 0.1 % w/w therefore triggers neither the Article 33 communication duty nor a SCIP notification (required since 5 January 2021), the two article duties that attach to Candidate List substances.

TEP needs no REACH authorisation either: the only flame retardants on Annex XIV are HBCD (entry 3) and TCEP (entry 13) in the consolidated REACH text of 1 September 2025, and a substance absent from the Candidate List cannot be placed on Annex XIV.

No Annex XVII entry for TEP is recorded in our source library, so that cell is being verified rather than written as "not restricted". Registration, authorisation and restriction are explained step by step on REACH and plastic additives.

Is triethyl phosphate allowed in food-contact plastics?#

We do not yet publish a food-contact status for triethyl phosphate: our source library carries no Annex I entry under Regulation (EU) No 10/2011 and no US 21 CFR or FCN citation for it, and an absent record is not an absent authorisation. The EU framework itself is definite: a substance missing from the Union list may not be used in EU food-contact plastics, the overall migration limit is 10 mg/dm2 (60 mg/kg for infant food) and the generic specific migration limit is 60 mg/kg. Rigid PU/PIR insulation and unsaturated polyester composites are not food-contact uses. The Union list, the migration limits and the declaration of compliance are explained on EU 10/2011.

What is the US status of triethyl phosphate?#

In the United States, the one rule our source library ties to triethyl phosphate is California AB 2998, which since 1 January 2020 has banned organophosphorus flame retardants above 1,000 ppm in juvenile products, mattresses and upholstered furniture. AB 2998 is a state law that works by chemistry and product category, so it reaches TEP only in those 3 product types, not in insulation foam or composites. State rules by chemistry, from California onward, are collected under US state laws on plastic additives.

TSCA, FDA food contact and California Proposition 65 have no record for TEP in our source library, so all three cells are being verified, and this page does not describe TEP as TSCA-listed, FDA-cleared or absent from Proposition 65. How EPA prioritises and evaluates a substance is explained on TSCA and plastic additives.

Is Triethyl Phosphate Hazardous? Classification and Safety Profile#

Triethyl phosphate carries one harmonised classification under the EU CLP Regulation, Acute Tox. 4 H302 (harmful if swallowed), and the eye-irritation statement Eye Irrit. 2 H319 that appears on supplier data sheets is a self-classification by notifying companies, not part of the harmonised entry.* The harmonised entry sits in Annex VI under index 015-013-00-7, and H302 is its only hazard statement.

A harmonised classification is a legal entry in Annex VI of the CLP Regulation that binds every supplier, while a notification is one company's own self-classification submitted to ECHA. Safety data sheets and search summaries that print H302 and H319 side by side mix those two layers: only H302 is harmonised for TEP. Harmonised and notified entries are separated on CLP classification of plastic additives.

Set beside two related phosphorus esters, TEP's classification covers fewer hazard classes than either: TCEP is harmonised Carc. 2 H351, Repr. 1B H360F, Acute Tox. 4* H302 and Aquatic Chronic 2 H411, and DMMP's notifiers report H340 by majority, plus H361 and H318/H319. Those are classifications, not a ranking by risk.

No LD50, exposure limit or environmental fate value for TEP is recorded in our source library, so this page states classifications only; the exposure evidence for the family is weighed on flame retardants and human health.

What Are the Alternatives to Triethyl Phosphate?#

Triethyl phosphate has 2 direct liquid alternatives, DMMP and TCPP, plus the phosphonate DMPP, the solid intumescent expandable graphite and reactive phosphorus polyols that are built into the polymer instead of blended into it. Table T6 compares the substances first by the two properties that decide a substitution, phosphorus per kilogram and halogen content, and then by regulatory and hazard position.

Table T6. Triethyl phosphate and 4 alternatives compared.

Footnote: phosphorus percentages marked "derived" are calculated from the molecular formula (30.97 g/mol of phosphorus per mole), not taken from a supplier data sheet. Reactive phosphorus polyols are a class, not a single substance, and have no row. Status 24 October 2026.

The selection logic follows the table: a halogen-free specification excludes TCPP, a phosphorus-per-kilogram target favours DMMP, and viscosity control favours TEP.

TEP vs DMMP#

DMMP delivers more phosphorus per kilogram than triethyl phosphate, about 25 % against 17 %, but TEP boils 34 °C (61.2 °F) higher, carries a harmonised classification limited to Acute Tox. 4 H302, and thins the polyol or resin it is added to.* Matching DMMP's phosphorus takes about 1.47 kg of TEP for every 1 kg of DMMP, a ratio derived from the two formulae and not a dosage recommendation. The boiling points, 215 °C (419 °F) against 181 °C (357.8 °F), also separate the two liquids, and why DMMP sits under Chemical Weapons Convention Schedule 2 is explained on its own page.

TEP vs TCPP#

TCPP is the chlorinated incumbent in rigid PU and PIR foam and triethyl phosphate is the halogen-free liquid beside it: TEP carries about 17 % phosphorus and no chlorine, against TCPP's 9.5 % phosphorus and 32.5 % chlorine. Per kilogram, TEP therefore delivers about 1.8 times the phosphorus of TCPP, a ratio derived from the two compositions. TCPP is also named in the EU toy limit of 5 mg/kg under Directive 2014/79/EU and in ECHA's 2018 childcare-article screening, with restriction work on hold since 2019, while TEP is named in neither. Rigid formulations also use TEP as an extra-phosphorus liquid beside TCPP, whose grades and producers, including Fyrol PCF and Levagard PP, are listed on its own page.

TEP vs DMPP, expandable graphite and reactive phosphorus polyols#

The closest halogen-free relative with a published loading is dimethyl propylphosphonate (DMPP), a phosphonate that ECHA's plastic additives initiative mapping records at about 15 wt% in polyurethane, a figure that belongs to DMPP and not to TEP. DMPP (CAS 18755-43-6) carries about 20 % phosphorus, derived from its formula, and is registered under REACH for intermediate use only.

Expandable graphite is the solid route: its grey-black flakes expand from about 200 °C (392 °F), within an onset range of 140 to 230 °C (284 to 446 °F), into an insulating layer. That colour limit separates expandable graphite from a colourless liquid such as TEP. Reactive phosphorus polyols close the set: built into the polymer backbone, they cannot migrate, which is the structural argument against every additive liquid, TEP included.

Who Supplies Triethyl Phosphate? Grades, Price and Sourcing#

We do not publish a triethyl phosphate producer list yet: our source library holds no verified manufacturer or trade name for TEP, and this site names a company only when a primary source supports it. Catalogue listings for triethyl phosphate manufacturers and suppliers circulate, but none is verified in our record. Producers verified by chemistry and region are listed under flame retardant manufacturers and suppliers.

Four documents answer the sourcing question in place of a producer name, listed below.

• Certificate of analysis: the assay of the delivered lot.
• Safety data sheet: the harmonised H302 and, usually, the notified H319.
• Technical data sheet: for the intended polyol blend, polyester resin or cellulose acetate.
• REACH confirmation: the supplier's registration for EU deliveries.

Our source library holds no bulk triethyl phosphate price, so this page gives none; laboratory pack prices per 25 g or 500 g say nothing about bulk prices. Buyers should compare quotations per kilogram of phosphorus delivered, because TEP, DMMP and TCPP differ in phosphorus content by a factor of more than two. Price guides and drivers for additive families are collected under plastic additive prices.

Where Does Triethyl Phosphate Sit in the Phosphorus Flame Retardant Family?#

Triethyl phosphate is the smallest alkyl phosphate ester among the flame retardants on this site, a member of the phosphate-ester branch of the phosphorus flame retardants, which sits beside the phosphonates, the phosphinates, red phosphorus and ammonium polyphosphate. The branches share the same two routes and differ in structure: phosphate esters such as TPP, RDP, BDP, TCPP and TEP, phosphonates such as DMMP and DMPP, and phosphinates such as DEPAL. TEP is an additive flame retardant, and the difference from a bound-in one is defined under reactive vs additive flame retardants.

Triethyl, triphenyl and tricresyl phosphate: three different esters#

Triethyl, triphenyl and tricresyl phosphate share the phosphate-ester core and differ in what sits on the three oxygens: ethyl groups make TEP a light alkyl liquid, while phenyl and cresyl rings make the other two aryl phosphates. The 3 esters are listed below.

• Triethyl phosphate (CAS 78-40-0, C6H15O4P): the alkyl ester, not an SVHC.
• Triphenyl phosphate (CAS 115-86-6, C18H15O4P): an aryl flame retardant and plasticizer in PC/ABS, PPE/HIPS, PVC and cellulose acetate film; triphenyl phosphate has been an SVHC since 7 November 2024.
• Tricresyl phosphate (CAS 1330-78-5, C21H21O4P): a flame-retardant plasticizer for PVC and cellulosics, not an SVHC (the related trixylyl phosphate has been one since 16 December 2013); what tricresyl phosphate is used for is answered on its own page.

TEP and TCEP: two alkyl phosphates with a viscosity role#

TCEP is the chlorinated alkyl phosphate that once held the same double role as triethyl phosphate, flame-retardant plasticizer and viscosity regulator, and it has needed REACH authorisation since its Annex XIV sunset date of 21 August 2015. Listed as toxic for reproduction, TCEP has been on the Candidate List since 13 January 2010 and on Annex XIV as entry 13, and no EU production has been recorded since 2001.

The shared role is the only link drawn here; no record shows TEP replacing TCEP. TCEP sits with TCPP and TDCPP among the chlorinated phosphates, compared with Dechlorane Plus and the chlorinated paraffins under chlorinated flame retardants.

Non-plastics uses of triethyl phosphate#

Outside plastics, triethyl phosphate is used as a catalyst and as a general solvent, uses that lie outside this site's scope, which covers additives in plastics. Catalysts and synthesis chemistry are not plastic additives, so the reactions TEP catalyses and the solvent markets it serves are not described here.

Is triethyl phosphate banned?#

No: no ban on triethyl phosphate is recorded in our source library; it is not an SVHC, needs no REACH authorisation, and the one rule that reaches it, California AB 2998, restricts organophosphorus flame retardants above 1,000 ppm in three product categories rather than the substance itself. Bans by chemistry, furniture standards and UL/IEC requirements are compared under flame retardant regulations.

Does triethyl phosphate migrate out of foam?#

It can: triethyl phosphate is an additive flame retardant, blended into the foam rather than bound to the polymer, and every unbound liquid can migrate, which is why reactive phosphorus polyols are designed into the backbone instead. No migration or emission value for TEP in foam is recorded in our source library; diffusion, blooming and the models that predict them are explained under additive migration in plastics.