Pentaerythritol: Properties, Uses in Plastics and Regulatory Status

Pentaerythritol (PENTA, CAS 115-77-5) is a polyol with four hydroxyl groups that works in plastics as a co-stabilizer in calcium-zinc PVC systems and as the carbon source of intumescent flame retardants. Pentaerythritol is better known outside plastics, in alkyd resins for paints and in synthetic ester lubricants, which raises the question of what the plastics industry actually does with a tetrol.

It does four things with it. Pentaerythritol acts as a polyol co-stabilizer that holds zinc chloride in a calcium-zinc package, as the carbon source of an intumescent flame retardant, as the chemical backbone of four other additive classes, and as a polyhydric-alcohol heat stabilizer in polyamide. Its status is dated and narrow: the European Union lists pentaerythritol in Annex I of Regulation (EU) No 10/2011 as FCM substance 279 with no specific migration limit, the United States caps it at 0.4 wt% of a rigid PVC article under 21 CFR 178.2010, and it does not appear on the California Proposition 65 list published on 31 July 2026. Pentaerythritol is one of 437 substance profiles in our directory of plastic additives, each carrying the same identity, dosage and regulatory fields.

This page carries the data-sheet view and the compliance view together: the tetrol structure, the PubChem constants and the melting-point conflict between sources, the mechanism of each role, the only levels any source actually publishes, the two test families, a regulatory matrix dated 23 September 2026, the comparison with dipentaerythritol and THEIC, and the grade structure a buyer meets instead of a trade name.

Table T1. Pentaerythritol identity card.

Footnote: identity and physical data from PubChem CID 8285 and ECHA substance 100.003.732; technical-grade composition from the NIOSH Pocket Guide; regulatory entries from the legal texts cited in each section. Status as of 23 September 2026.

What Is Pentaerythritol?#

Pentaerythritol is a solid tetrol, a single carbon atom carrying four hydroxymethyl groups, with the formula C(CH2OH)4 and a molecular weight of 136.15 g/mol. The systematic name, 2,2-bis(hydroxymethyl)propane-1,3-diol, describes the same architecture from the other direction: a propane-1,3-diol chain whose central carbon carries two further hydroxymethyl substituents. That central carbon is quaternary and bears no hydrogen, which is the neopentyl core. Pentaerythritol is supplied as a colourless to white crystalline odourless powder, and its commercial synonyms include monopentaerythritol and PETOL. Which of those four hydroxyl groups matter to a plastics formulator?

All four matter, because both plastics functions are hydroxyl-count functions. The four primary hydroxyl groups are the sites that complex zinc chloride in a PVC stabilizer package, and the same four hydroxymethyl arms are the carbon that an acid source dehydrates into char in an intumescent flame retardant. Pentaerythritol therefore enters plastics through two additive families at once. As a co-stabilizer it belongs to the PVC stabilizer family, and the hub on PVC heat stabilizers compares every class in it, from the calcium-zinc and organotin systems to the lead salts being phased out.

Is pentaerythritol a polyol, and is it an alcohol?#

Yes: pentaerythritol is a polyol, and a polyol is a type of alcohol, so both questions have the same answer. A polyol carries more than one hydroxyl group; pentaerythritol carries four, which makes it a tetrol, also written tetrahydric alcohol or polyhydric alcohol. The four hydroxyl groups are all primary, each sitting on a terminal CH2 carbon rather than on the quaternary centre, which is why the molecule esterifies cleanly at all four positions and gives the tetraesters that dominate its use in plastics.

Why pentaerythritol is never abbreviated "PE" in plastics#

Pentaerythritol is abbreviated PENTA or PER in plastics literature, never PE, because PE is the standard abbreviation for polyethylene. Regulatory texts avoid the abbreviation question entirely: 21 CFR 178.2010 expresses its limit "as free pentaerythritol", spelled out in full, and names the stearate ester separately rather than using any short form.

Mono-, di- and tripentaerythritol: what technical grade contains#

Technical-grade pentaerythritol is a mixture: the NIOSH Pocket Guide gives roughly 88 % monopentaerythritol and 12 % dipentaerythritol, so a delivered lot is never a single substance. The 12 % of dipentaerythritol in a technical grade is a substance with its own CAS number and its own FCM number, which matters when a food-contact declaration has to name every intentionally added substance. The three members of the series are listed below.

• Monopentaerythritol, CAS 115-77-5, C5H12O4, 136.15 g/mol, the substance this page covers and the majority component of a technical grade.
• Dipentaerythritol, CAS 126-58-9, C10H22O7, 254.28 g/mol, the ether dimer with six hydroxyl groups, listed separately as FCM substance 311.
• Tripentaerythritol, the ether trimer, named with the other two in the DuPont polyamide patent claim and not held as a separate record in our source library.

Purity grades quoted as "98 %" or "99 %" appear on supplier listings rather than in any verified data set behind this page, so no purity specification is stated here as a fact.

What Does Pentaerythritol Do in Plastics? 4 Additive Roles#

Pentaerythritol fills 4 roles in plastics: polyol co-stabilizer in calcium-zinc PVC systems, carbon source in intumescent flame retardants, chemical backbone of four other additive classes, and polyhydric-alcohol heat stabilizer in polyamide. Two of those roles put the molecule itself into the compound, and two put it in as part of a larger molecule, which is why a search for pentaerythritol in plastics returns both a raw polyol and a shelf of branded esters. The 4 roles are listed below.

• Polyol co-stabilizer in PVC, where pentaerythritol complexes the zinc chloride generated by a zinc soap and delays zinc burning in a calcium-zinc package.
• Carbon source in intumescent flame retardants, where an acid source such as ammonium polyphosphate dehydrates it to char and a blowing agent such as melamine swells that char.
• Additive feedstock, the backbone of hindered-phenol antioxidants, spiro diphosphite antioxidants, ester lubricants and release agents, and polyol-ester plasticizers.
• Polyhydric-alcohol heat stabilizer in polyamide, claimed for PA6 and PA66 alongside dipentaerythritol and tripentaerythritol in patent literature.

How does pentaerythritol stabilize PVC?#

Pentaerythritol stabilizes PVC indirectly: it chelates the zinc chloride that forms when a zinc soap substitutes a labile chlorine atom, which delays zinc burning and extends the long-term stability of a calcium-zinc system. Why does a calcium-zinc package need a second additive at all? Because the zinc carboxylate that gives the compound its good early colour is also the source of the zinc chloride that destroys its late stability. Ye and colleagues set out that sequence in 2025, and Lévai and colleagues described the same exchange chemistry in 1989: the zinc carboxylate replaces labile chlorine on the polymer and produces ZnCl2, the calcium carboxylate scavenges the hydrogen chloride released and regenerates the zinc soap by ligand exchange, ZnCl2 + Ca(OOCR)2 giving Zn(OOCR)2 + CaCl2. Polyols are one of the 5 groups of PVC co-stabilizers that a commercial package carries, beside beta-diketones, hydrotalcite or zeolite, epoxides and phosphites.

Regeneration is never complete, and the residue is what the polyol handles. Zinc chloride that escapes ligand exchange accumulates in the melt and catalyses further dehydrochlorination, so a hydroxyl-rich molecule that coordinates the zinc ion removes the catalyst from circulation. Unstabilized PVC begins to lose hydrogen chloride above about 70 °C (158 °F) and its thermal degradation runs from around 250 °C (482 °F), well inside the processing window of rigid pipe and profile. Michel, Van Hoang and Perrin showed in 1981 that the beta-diketone and the calcium-zinc soaps work as a synergistic set rather than as independent additives, and the ligand exchange that regenerates the zinc soap is the defining synergy of calcium-zinc stabilizers.

What is zinc burning, and how does a polyol stop it?#

Zinc burning is the sudden blackening of a PVC compound once accumulated zinc chloride starts catalysing dehydrochlorination faster than the stabilizer can neutralise it. A polyol stops it by complexing that zinc chloride, which removes the Lewis acid that drives the autocatalytic step. The comparison with lead makes the mechanism visible: lead chloride is only weakly Lewis-acidic, so lead-stabilized compounds show no equivalent failure, while zinc chloride is strongly Lewis-acidic and has to be countered deliberately by polyols, phosphites, beta-diketones and hydrotalcite. The margin is small, because a degree of dehydrochlorination of 0.1 % is already enough to cause unacceptable discoloration, a threshold covered in detail under PVC thermal degradation and dehydrochlorination.

How does pentaerythritol work in intumescent flame retardants?#

Pentaerythritol is the carbon source of a classic intumescent system: ammonium polyphosphate supplies the acid, pentaerythritol supplies the carbon that the acid dehydrates into char, and melamine supplies the gas that swells that char into a foam. The three-component description comes from the intumescent and ammonium polyphosphate literature rather than from a single primary experiment, and it applies to a reaction that happens in the melt, not on a surface. The acid source is ammonium polyphosphate, which releases ammonia and phosphoric acid as it decomposes; the phosphoric acid esterifies and then dehydrates the hydroxyl groups of the polyol; the released gases expand the carbonising mass into a low-density insulating layer that cuts heat transfer to the polymer beneath.

At what temperature does the sequence start? Phase II ammonium polyphosphate, the long-chain grade used in compounds, begins to decompose from about 240 °C (464 °F), and that figure sets the processing ceiling rather than the performance point. Formulated ammonium polyphosphate systems for polypropylene are specified for processing up to about 220 °C (428 °F), which keeps the compound below the onset of the acid source during extrusion and injection moulding. Our source library holds no decomposition temperature and no char-yield figure measured on pentaerythritol itself, so this page attaches no pentaerythritol-specific temperature to the sequence. One caution applies to anything read on this subject: almost all published intumescent material describes paint films, while the chemistry described here is the thermoplastic-compound version. The full three-component chemistry of intumescent flame retardants is set out on the class page, and the blowing agent, melamine, has carried a place on the REACH Candidate List since 17 January 2023, which makes the choice of nitrogen source a compliance question as well as a performance question.

Pentaerythritol as the backbone of 4 other additive classes#

Four additive classes are built on the pentaerythritol molecule: hindered-phenol antioxidants, spiro diphosphite antioxidants, ester lubricants and release agents, and polyol-ester plasticizers. Each one uses the same four primary hydroxyl groups as attachment points, so the parent polyol appears in the chemical name of every product in the group. The five best-documented derivatives are compared in the table below.

Table T7. Additives built on the pentaerythritol molecule.

Footnote: distearyl pentaerythritol diphosphite (Weston 618) and bis(2,4-dicumylphenyl) pentaerythritol diphosphite (Doverphos S-9228) are further members of the diphosphite group.

The commercial consequence is a naming problem rather than a chemistry problem. A buyer who searches for pentaerythritol in a plastics context is usually looking for one of these esters rather than for the polyol itself, because the esters are sold as finished additives with trade names while the polyol is a commodity intermediate. The highest-volume example is Irganox 1010, a pentaerythritol tetraester of a hindered phenol with a molecular weight of 1177.6 g/mol, made by a Michael addition of methyl acrylate to 2,6-di-tert-butylphenol followed by transesterification with pentaerythritol.

What Are the Physical and Chemical Properties of Pentaerythritol?#

Pentaerythritol is a colourless to white crystalline odourless powder that melts at 258 to 260.5 °C (496.4 to 500.9 °F) and has a density of 1.38 to 1.40 g/cm3 at 25 °C (77 °F). The high melting point for a molecule of 136.15 g/mol follows from the hydrogen-bonding network that four primary hydroxyl groups build in the crystal, and it is the reason the powder reaches a compounding extruder unchanged. The full constants are given below.

Table T2. Physical and chemical properties of pentaerythritol.

Two gaps in that table are deliberate. Values on this page follow PubChem (CID 8285), while Google's AI Overview and the Sigma-Aldrich catalogue print a melting point of 253 to 258 °C (487.4 to 496.4 °F), so check which source a data sheet follows before comparing lots. No water-solubility figure is recorded in our source library, and the row is left out rather than filled with a qualitative substitute, even though solubility in water is one of the most frequent questions asked about the substance.

Which Polymers Use Pentaerythritol, and at What Level?#

The only regulated level for pentaerythritol in plastics is a ceiling, not a recipe: US food-contact rules cap it at 0.4 wt% of a rigid PVC article, counted as free pentaerythritol including its stearate ester. No source in our source library publishes a recommended dosage for pentaerythritol as a PVC co-stabilizer, in phr or in weight percent, and this page prints none. The same absence applies to dipentaerythritol, THEIC, ADMU, dibenzoylmethane, stearoylbenzoylmethane and the lead salts.

How do phr values convert to weight percent? Stabilizer recipes are written in PHR (parts per hundred resin), which converts to weight percent by dividing the part by the sum of all parts in the formulation and multiplying by 100. The whole stabilizer package sits at 1 to 5 % of a PVC formulation according to the European Council of Vinyl Manufacturers, with 2 to 4 % typical according to Ullmann's Encyclopedia, and Wiesinger and colleagues put heat plus UV stabilization at 0.05 to 5 wt% in their 2024 additive inventory. The pentaerythritol share of that window is published nowhere, so a formulator has to obtain it from the one-pack producer.

Table T3. Published levels for pentaerythritol and the systems it sits in.

Pentaerythritol in rigid PVC#

Rigid PVC is the application the regulators name: the US food-contact rule writes its 0.4 wt% ceiling for pentaerythritol into rigid PVC only, and rigid pipe and profile are where calcium-zinc one-packs carry polyols. A polyol reaches that compound inside a one-pack rather than as a separate metered addition, which is why the line items in a public recipe describe the package and not its components. The Plastics Pipe Institute technical report TR-2 gives a range composition for US PVC pressure pipe of 0.3 to 1.0 phr heat stabilizer, 0.4 to 1.5 phr calcium stearate, 0.6 to 1.5 phr paraffin wax, 0 to 0.3 phr polyethylene wax, 0.5 to 3.0 phr titanium dioxide, 0 to 5.0 phr calcium carbonate and 0 to 2.0 phr process aid. The 0.3 to 1.0 phr line covers the entire heat stabilizer, metal soaps and co-stabilizers together, and none of it is a pentaerythritol figure. Where the polyol sits in a complete recipe is shown in rigid PVC formulations.

Pentaerythritol in intumescent polypropylene#

Intumescent polypropylene is the main thermoplastic home of pentaerythritol as a flame retardant: formulated ammonium polyphosphate systems reach UL 94 V-0 at 22 to 30 wt% of the compound, with processing up to about 220 °C (428 °F). Those 22 to 30 wt% describe the total flame-retardant system, acid source plus carbon source plus synergists, and not the pentaerythritol content, and the ratio of ammonium polyphosphate to pentaerythritol to melamine is not recorded in our source library. Metal oxides can lift the result further: in a 2025 study in the journal Polymers on intumescent polypropylene built from ammonium polyphosphate and pentaerythritol, 0.25 wt% of zinc oxide or manganese oxide produced a limiting oxygen index of 30 vol % O2 with a V-0 rating, and 1.5 wt% of zinc oxide produced 43.7 vol % O2. A nitrogen-phosphorus alternative reaches the same rating at a lower loading, since a piperazine pyrophosphate and melamine polyphosphate one-pack in a 2:1 ratio can give UL 94 V-0 in polypropylene at 21 wt% total, in virgin and in recycled resin alike. Competing systems at the same loading are compared on flame retardants for polypropylene.

Polyhydric alcohols in polyamide (PA6 and PA66)#

Polyamide is the second polymer where the pentaerythritol family acts as a stabilizer in its own right, above the temperature at which copper-halide systems start to fall behind. DuPont claimed that use in US patent application 2010/0029819 A1, with a priority date of 30 July 2008, covering pentaerythritol, dipentaerythritol and tripentaerythritol at 0.25 to 15 wt%, preferably 0.25 to 8 %, as heat stabilizers for polyamide. Every performance number in the patent belongs to dipentaerythritol rather than to pentaerythritol. In the patent examples, a PA66 with 30 % glass fibre and 3 % dipentaerythritol retained 99.1 % of its tensile strength after 500 hours at 210 °C (410 °F) and 94.8 % after 1000 hours, against 78.2 % for a copper-only control, while 1.5 % dipentaerythritol gave 89.3 %; a PA6 with 3 % dipentaerythritol exceeded 100 % tensile retention after 1000 hours at 210 °C against about 52 % for its copper control. These are patent examples from a single assignee, not independent test data. Copper-halide systems and their limits are covered on heat stabilizers for nylon.

What Is Pentaerythritol Used For in Plastics?#

Pentaerythritol is used in 5 plastics applications: calcium-zinc stabilized rigid PVC, intumescent polypropylene compounds, food-contact PVC articles, heat-aged polyamide, and the manufacture of other additives. Those five are the plastics answer to a question that general search results answer with alkyd resins and lubricants, real markets that are not plastics markets. The 5 plastics applications are listed below.

• Rigid PVC pipe and profile, where the polyol sits inside a calcium-zinc one-pack and extends long-term stability.
• Intumescent compounds, mainly polypropylene, where pentaerythritol is the carbon source of the char.
• Food-contact plastics, where pentaerythritol is authorised as FCM substance 279 in the EU and capped at 0.4 wt% in rigid PVC in the US.
• Polyamide, PA6 and PA66, where polyhydric alcohols are claimed as heat stabilizers for long-term ageing above 200 °C (392 °F).
• Additive manufacture, as the alcohol component of hindered-phenol antioxidants, spiro diphosphites, ester lubricants and polyol-ester plasticizers.

How Is the Effect of Pentaerythritol Measured?#

Two different test families measure pentaerythritol, because it has two different jobs: PVC thermal stability tests for the co-stabilizer role and fire tests for the char-former role. Neither family measures the polyol on its own; both measure a compound that contains it, which is why a result is interpretable only against a stated formulation and a stated specimen geometry. The four methods are set out below.

Table T4. Test methods for the two roles of pentaerythritol.

No Congo red or oven-ageing result measured on a pentaerythritol-containing formulation is recorded in our source library, so the one quoted stability figure belongs to a different additive set. Jiang and colleagues reached 190 minutes to full blackening in static oven ageing at 180 °C (356 °F) in Materials in 2020, with 2.4 phr hydrotalcite, 0.3 phr zinc stearate and 0.3 phr zinc acetylacetonate, and the Congo red time in the same study reached a maximum of 46 minutes. ISO 182-1 and static oven ageing are described step by step under PVC heat stability testing, and the test temperature in the Congo red method is set by the laboratory rather than fixed by the standard.

Fire testing answers a different question. The limiting oxygen index (LOI) is the minimum oxygen concentration in a flowing oxygen and nitrogen mixture that just supports flaming combustion, measured to ASTM D2863-23e1 or ISO 4589-2 and reported in vol % O2 rather than in bare percent. Air sits at about 21 vol % O2, unmodified polypropylene at 17.5 to 17.8 vol % O2, and intumescent polypropylene compounds at 29 to 33 vol % O2.

A rating is not a number in the same sense. UL 94 sorts a specimen into classes, and a V-0 result requires each afterflame to last 10 seconds or less, the total for five specimens to stay at 50 seconds or below, afterflame plus afterglow after the second application to stay at 30 seconds or below, and no ignition of the cotton beneath the specimen. A V-0 result is meaningless without its thickness, as UL 94 flammability ratings sets out, because the same compound can pass at 3.2 mm and fail at 0.8 mm.

How Does Pentaerythritol Interact with Other PVC Additives?#

Pentaerythritol never works alone: a commercial calcium-zinc package pairs it with a beta-diketone for early colour, hydrotalcite or a zeolite for hydrogen chloride uptake, a phosphite for clarity and zinc chloride control, and an epoxide such as epoxidized soybean oil. The four partners and their jobs are listed below.

• Beta-diketones, such as dibenzoylmethane (DBM) and stearoylbenzoylmethane (SBM), which C-alkylate labile chlorine under zinc catalysis and give very good early colour; the FDA caps stearoylbenzoylmethane at 0.5 wt% of vinyl chloride homopolymers in the same section that caps pentaerythritol at 0.4 wt%.
• Hydrotalcite, a magnesium-aluminium layered double hydroxide, which takes up hydrogen chloride by neutralisation and by exchanging interlayer carbonate for chloride, and which is a standard long-term component of calcium-zinc systems.
• Phosphites, such as triphenyl phosphite at 10 % phosphorus, diphenyl isodecyl phosphite at 8.3 %, 2-ethylhexyl diphenyl phosphite at 9.0 % and tris(nonylphenyl) phosphite at 4.4 %, which complex zinc chloride, decompose hydroperoxides and can replace labile chlorine by an Arbuzov-type reaction.
• Epoxides, chiefly epoxidized soybean oil, whose oxirane groups scavenge hydrogen chloride to form chlorohydrins in a reaction catalysed by the zinc and calcium soaps.

Does the polyol compete with the phosphite, since both complex zinc chloride? Both are recorded as zinc chloride complexing agents, and no comparative study ranking one against the other is held in our source library, so the choice falls on secondary properties such as clarity, hydrolytic stability and food-contact listing. ESBO (epoxidized soybean oil) is the clearest case of a partner with a second job, since it plasticizes as well as scavenges and carries a specific migration limit of 60 mg/kg under EU food-contact rules, reduced to 30 mg/kg for PVC gaskets on infant-formula jars.

The package is therefore a system decision rather than a component decision, and the complete formulation, from the metal soaps through the lubricants and impact modifiers to the fillers, is mapped on additives for PVC.

What Is the Regulatory Status of Pentaerythritol?#

Pentaerythritol is authorised for EU food-contact plastics as FCM substance 279 with no specific migration limit, is capped at 0.4 wt% in rigid PVC by US food-contact rules, is not on the Proposition 65 list published on 31 July 2026, and is not a persistent organic pollutant, as of 23 September 2026. Four cells of the matrix below carry no verified value, and each one reads "status being verified" rather than being filled by inference.

Table T5. Regulatory matrix for pentaerythritol, as of 23 September 2026.

An Annex I listing without a specific migration limit is not an absence of control. What an Annex I listing without an SML means in practice is explained on EU 10/2011: the substance is authorised, the overall migration limit of 10 mg/dm2 still applies to the article, and the purity requirements of the regulation still apply to the substance.

Is pentaerythritol allowed in food-contact plastics?#

Yes in both jurisdictions: the EU lists pentaerythritol in Annex I of Regulation (EU) No 10/2011 as FCM substance 279 with no specific migration limit, and the US lists it in 21 CFR 178.2010 with a 0.4 wt% ceiling in rigid PVC. The EU entry carries two reference numbers, 22840 for the substance used as a monomer or starting material and 71600 for the substance used as an additive, in the consolidated text of 16 March 2025, and "no SML" means no substance-specific numeric limit while the overall migration limit of the regulation continues to apply to the finished article. Dipentaerythritol is listed separately as FCM substance 311, so a technical grade containing both components is covered by two entries rather than one.

The US position is a listing with a limitation rather than an approval. Section 178.2010 covers antioxidants and stabilizers for polymers, and pentaerythritol is listed there subject to its limitation; the same section caps stearoylbenzoylmethane at 0.5 wt% and the methyltin blend at 2 wt% in rigid PVC, which puts the pentaerythritol ceiling at the lower end of that group. Pentaerythritol is additionally listed in 21 CFR 175.300, the resinous and polymeric coatings section.

What does the FDA 0.4 % limit in rigid PVC mean?#

The 0.4 % figure is a legal ceiling, not a formulation target: 21 CFR 178.2010 allows up to 0.4 wt% of a rigid PVC article, calculated as free pentaerythritol and counting any pentaerythritol stearate present. Two elements of that wording do the work. "As free pentaerythritol" means the calculation converts the ester content back to the parent polyol rather than counting the ester by its own mass, and "rigid PVC" means the ceiling is written for rigid articles specifically, not for flexible compounds. FDA percentages in this part are maxima that a compound must not exceed, and a formulator who reads one as a recommended dosage has read it backwards. Section 178.2010 and its limitation column are explained on FDA food contact rules for plastic additives (21 CFR).

Is pentaerythritol registered under REACH, and is it an SVHC?#

The REACH position of pentaerythritol is not established on this page: neither its registration record nor its Candidate List status has been verified against a primary ECHA source for this substance. Registration and the Candidate List are two different obligations under REACH, and this page can confirm neither. The REACH registration number and tonnage band are not recorded in our source library, so no registration status is stated here.

The Candidate List position is recorded but unverified. Our sources hold pentaerythritol as not listed, but the Candidate List dates for this family came from third-party compilations rather than from ECHA directly, so the entry is treated as outstanding rather than as a negative finding. Every PVC stabilizer component with a confirmed place on the SVHC Candidate List is tracked on one page, and pentaerythritol will be stated here with its verification date once the check has been made directly against ECHA.

Is pentaerythritol listed under California Proposition 65?#

No: pentaerythritol does not appear on the California Proposition 65 list published on 31 July 2026, and neither does dipentaerythritol. The list is republished by the Office of Environmental Health Hazard Assessment as chemicals are added, so the date of the list version checked is part of the answer rather than a footnote to it, and listing dates for every plastic additive we cover are on California Proposition 65.

Is Pentaerythritol Safe? Health, Safety and Environmental Profile#

Pentaerythritol carries no harmonised hazard classification in the sources checked, and the notifications aggregated for it are mostly "not classified", with a single notification of H412, harmful to aquatic life with long lasting effects. Those notifications are company self-classifications submitted to the classification and labelling inventory, not decisions by an authority, which matters when an aggregated GHS record is read as though it were a harmonised entry under Annex VI of the CLP Regulation. Three elements make up the recorded profile.

• Classification: no harmonised classification under Regulation (EC) No 1272/2008 was found for pentaerythritol in the sources behind this page.
• Notifications: mostly "not classified", with one notification of H412, harmful to aquatic life with long lasting effects, submitted by a notifier rather than assigned by ECHA.
• Regulatory negatives: not on the California Proposition 65 list of 31 July 2026, and not listed under the EU POPs Regulation (EU) 2019/1021.

The co-stabilizers pentaerythritol sits beside carry more notified hazards than it does. THEIC carries notified H315, H319 and H335 for skin irritation, serious eye irritation and respiratory irritation, and dibenzoylmethane carries a notified H317 for skin sensitisation, while the pentaerythritol record stays at a single environmental statement. No LD50, no NOAEL, no occupational exposure limit and no dust-explosion parameter for pentaerythritol is held in our source library, so none is printed here, and this page makes no unqualified claim that the substance is safe, non-toxic or food grade.

What Are the Alternatives to Pentaerythritol?#

The 4 polyol alternatives to pentaerythritol in a calcium-zinc system are dipentaerythritol, THEIC, sorbitol and trimethylolpropane, and the choice between them turns on food-contact listing rather than on published performance. No comparative performance study between these polyols is held in our source library, so the table below compares them on identity, food-contact listing and hazard status only, and not on stabilizing efficiency.

Table T6. Pentaerythritol compared with dipentaerythritol and THEIC.

Footnote: sorbitol and trimethylolpropane are named as polyol co-stabilizers in the same source but have no substance page and no verified data set in our source library. The SVHC column reads "verification pending" because the Candidate List check for this family was made through third-party compilations rather than directly against ECHA.

Pentaerythritol vs dipentaerythritol#

Dipentaerythritol is the ether dimer of pentaerythritol, with six hydroxyl groups instead of four, a molecular weight of 254.28 g/mol and a lower melting point of 212 to 220 °C (413.6 to 428 °F). Its CAS number is 126-58-9, its EC number 204-794-1, its formula C10H22O7 and its density 1.33 g/cm3, and it is authorised in EU food-contact plastics as FCM substance 311 with no specific migration limit. The two polyols are not really competitors, because about 12 % of a technical-grade pentaerythritol is already dipentaerythritol, so a compounder buying the cheaper grade is buying a mixture of both.

The recorded difference is in emphasis rather than in measured performance. Our source library associates dipentaerythritol with long-term stability in calcium-zinc systems and with char formation in intumescent systems, the same two roles pentaerythritol fills, and it holds no comparative measurement that would justify a claim that six hydroxyl groups outperform four. As a dipentaerythritol co-stabilizer it is also the substance behind every polyamide number quoted on this page, since the DuPont patent examples used dipentaerythritol rather than the monomer.

Pentaerythritol vs THEIC#

THEIC is the nitrogen-containing alternative: tris(2-hydroxyethyl) isocyanurate carries three hydroxyl groups on an isocyanurate ring, melts at 135 °C (275 °F) and is not listed in Annex I of Regulation (EU) No 10/2011. Its CAS number is 839-90-7, its EC number 212-660-9, its formula C9H15N3O6 and its molecular weight 261.23 g/mol, and it is supplied as a white powder. THEIC (tris(2-hydroxyethyl) isocyanurate) is the nitrogen-containing polyol of the same co-stabilizer group, and it doubles as a building block for wire-enamel polyesters and for a triester antioxidant with its own CAS number, 34137-09-2.

The practical decision point is food contact, not chemistry. Pentaerythritol has an FCM number and a US food-contact listing; THEIC has neither, since it is absent from Annex I of the EU regulation and is not itself named in 21 CFR 178.2010, where only its triester appears. THEIC also carries more notified hazard statements, H315, H319 and H335, against the single H412 notification recorded for pentaerythritol, so a compound intended for food contact or for a low-hazard specification starts from pentaerythritol.

Sorbitol, trimethylolpropane and the other polyol options#

Sorbitol and trimethylolpropane appear in the same list of polyol co-stabilizers as pentaerythritol, without published dosage or food-contact data in the sources behind this page. Neither has a verified data set or a substance record in our substance directory yet, so this page names them and states nothing further about their identity, their levels or their regulatory position.

Who Manufactures Pentaerythritol? Grades and Suppliers#

Pentaerythritol reaches a compounder as a graded commodity rather than a branded additive: the grade is defined by its monopentaerythritol content, not by a trade name. No manufacturer and no trade name for pentaerythritol is recorded in our source library, and this page names no company rather than repeating a marketplace listing as though it were verified sourcing data. The grade structure a buyer meets is set out below.

Table T8. Pentaerythritol grades as they are traded.

Buyers should ask for the certificate of analysis with the mono and di content, plus the safety data sheet and a food-contact statement naming 21 CFR 178.2010 or FCM substance 279, because a grade name on an offer document carries none of that information. The commercial context is a stabilizer market rather than a pentaerythritol market: IMARC, a market-research house, puts the global PVC stabilizer market at USD 4.6 billion in 2024 and forecasts USD 6.9 billion by 2033, a market-research estimate and not an industry statistic. One-pack producers who buy pentaerythritol are listed under PVC stabilizer manufacturers, and they, rather than the polyol producers, are where most compounders meet this substance.

How Does Pentaerythritol Fit into the Wider Polyol Family?#

Pentaerythritol is the reference member of the polyol group, the class of multi-hydroxyl additives that calcium-zinc stabilizer packages use to hold zinc chloride and that intumescent systems use to make char. The polyol group sits beside the beta-diketones and the phosphites among the co-stabilizers for PVC, and it reaches beyond PVC in a way the other two do not, because a polyol is also an esterification substrate. That second identity puts the pentaerythritol name on antioxidant, lubricant and plasticizer labels, and makes the substance familiar in markets that have nothing to do with plastics.

Pentaerythritol esters in plastics: lubricants, antioxidants and plasticizers#

Most pentaerythritol that ends up in a plastic arrives as an ester: pentaerythritol tetrastearate as a mould release agent, hindered-phenol esters as antioxidants, and polyol esters as high-temperature plasticizers. Pentaerythritol tetrastearate, CAS 115-83-3, is covered by EU food-contact entry FCM 880 (ref 31348), "acids, fatty (C8-C22), esters with pentaerythritol", with no specific migration limit, and by FDA 21 CFR 177.1580(b) as a mould release agent at a maximum of 0.5 wt% of the finished polycarbonate resin, with food-contact notification FCN 001963 held by Peter Greven for saturated pentaerythritol esters. Pentaerythritol tetrastearate is the best-known of the ester lubricants used in engineering thermoplastics. In plasticizers, Hallstar groups specialty esters into low-temperature types, high-temperature types comprising trimellitates and pentaerythritol esters, and permanent polymeric types, and the commercial polyol-ester plasticizer in that middle group is pentaerythritol tetravalerate, CAS 15834-04-5, sold by Perstorp as Pevalen.

Non-plastics uses of pentaerythritol#

The largest markets for pentaerythritol sit outside plastics: alkyd resins for paints and varnishes, and synthetic ester lubricants. This reference covers the plastics use of the substance and does not follow it into coatings chemistry, lubricant formulation or any other non-plastics market, so those applications are named here and not described. No tonnage or share figure for any pentaerythritol end use is recorded in our source library, so this page does not quantify the split between the plastics and non-plastics markets.

How much does pentaerythritol cost?#

Pentaerythritol trades as a commodity polyol, priced per tonne on a commodity basis rather than as a branded additive. No price figure and no price range for pentaerythritol is recorded in our source library, so none is printed here. Price drivers for stabilizer raw materials are tracked under plastic additive prices.

Does pentaerythritol need an SDS?#

Yes: suppliers issue a safety data sheet for pentaerythritol as for any traded chemical, even though the aggregated notifications for it are mostly "not classified". A data sheet that records no hazard classification in section 2 is still the document that carries identity, handling, storage and the supplier's own assessment.

Is pentaerythritol the same as pentaerythritol tetranitrate?#

No: pentaerythritol tetranitrate (PETN) is a different substance with no use as a plastics additive, so it is outside the scope of this reference. Our source library holds no verified record for it, and this page therefore makes no statement about its identity or its chemistry.