Additives by Polymer: Formulation Guides for 20 Major Plastics

The host polymer decides the additive package: PVC cannot be melted without a heat stabilizer, polypropylene cannot be processed without an antioxidant, and polycarbonate rejects half the flame retardants that work in polyolefins, so this index holds one formulation guide for each of 20 major plastics. Each guide answers the same questions: which families, at what level, in which application, and under which legal limit?

Every polymer guide covers the additive requirements the polymer cannot do without, the full package family by family, typical formulations by application, and the processing window and regulatory context that set the dosage. That is a different entry point from plastic additives, which sorts by what a family does across every polymer rather than by what one polymer needs across every family.

This page explains why the package differs by polymer, maps 21 families against 14 polymers in one matrix, works through the package for every commodity, engineering, bio-based and recycled plastic, converts dosage between phr, weight percent and parts per million, collects the limits food-contact law writes per polymer, and closes with a 5-step process for building a package.

Table T1. The 20 polymer guides in this cluster

Why Every Polymer Needs a Different Additive Package#

Four properties of the polymer set its additive package: how the polymer degrades, how narrow its processing window is, what the end product has to do, and which legal limits are written for that polymer. PVC's chlorine content forces a heat stabilizer into every formulation before flexibility or colour ever enter the picture, while a high-performance polymer such as PEEK narrows the additive list to whatever survives a 343 °C melt. Processing window and end use then layer functional families on top of the mandatory stabilizer, and a legal limit can cap a dosage regardless of what the formulator would otherwise choose. These four determinants apply in the same order to every polymer in this index.

Degradation chemistry decides the stabilizer#

PVC is about 57 % chlorine by mass and starts to split off hydrogen chloride at 100-120 °C, which is why every PVC compound on the market contains a heat stabilizer, while polypropylene has a tertiary carbon on every repeat unit and loses molecular weight by beta-scission instead. Four degradation modes explain why the stabilizer package differs by polymer family:

• PVC. Dehydrochlorination begins at 100-120 °C and moves into rapid degradation near 250 °C; the compound needs a calcium-zinc, organotin or barium-zinc heat stabilizer before it reaches melt temperature.
• Polypropylene. Oxidation attacks the tertiary carbon on every repeat unit, and beta-scission raises melt flow rate as chains break, so the resin needs a phenolic antioxidant paired with a phosphite.
• Polyethylene. The same oxidative attack crosslinks the chain and forms gels instead, lowering melt flow rate rather than raising it, and the polymer needs the same antioxidant class paired with an acid scavenger.
• Polyamide. Long-term heat ageing above 150 °C degrades the amide backbone, and the polymer needs a copper halide stabilizer system (DuPont, US patent 2,705,227, 1954) dosed at 0.001-0.03 wt% copper with 0.1-5 wt% of a halide.

Polyesters and PLA fail by a third route, losing molecular weight through hydrolysis, and their packages add carbodiimide hydrolysis stabilizers instead of an antioxidant blend. Every one of these routes is a case of polymer degradation, the mechanism that decides which stabilizer family enters the package first.

The processing window decides the lubricants and processing aids#

A narrow processing window forces a lubricant package: rigid PVC pipe compounds carry paraffin wax at 0.6-1.5 phr, calcium stearate at 0.4-1.5 phr and up to 2.0 phr of acrylic processing aid within the PPI TR-2-2023 range composition, because the melt fuses only a few degrees below the temperature at which it degrades. Engineering polymers face the same constraint from the opposite side: they process at roughly 240-320 °C, and PEEK runs above 340 °C, a window that excludes aluminium trihydroxide, most ammonium polyphosphate flame retardants and low-molecular-weight phenolic antioxidants, because those additives decompose before the melt does. Fluoropolymer processing aids follow the same logic on the olefin side: 21 CFR 177.1520 limits them to 0.2 wt% in olefin polymers with 65-71 % fluorine content.

The lubricant balance in rigid PVC works because each ingredient does a different job:

1. Internal lubricants such as calcium stearate reduce polymer-to-polymer friction and control fusion.
2. External lubricants such as paraffin wax and PE wax reduce friction at the die and screw.
3. Acrylic processing aids raise melt strength so the compound fuses before it degrades.

Processors track the change in melt flow rate (MFR) across extrusion passes to confirm the lubricant package is still working.

The end use decides the functional additives#

The same polymer takes three different packages depending on what it has to do: polyethylene for pressure pipe carries 2.0-2.5 wt% carbon black and has to keep an oxidative induction time of at least 20 minutes at 210 °C, while polyethylene for blown film carries 500-1,200 ppm of slip additive and 2,500-10,000 ppm of antiblock instead. Pressure pipe compounds (EN 12201-1 / ISO 4427-1) use carbon black with a 10-25 nm primary particle size to block UV and oxidation over decades underground, a job film additives never have to do. Intumescent polypropylene takes a third package again, reaching a UL 94 V-0 rating with 22-30 wt% ammonium polyphosphate instead of a carbon black or slip package.

This third determinant, what the finished part has to do, is the organising axis of plastic additives by application, the sibling reference to this polymer-first index.

The polymer decides the legal limit#

Food-contact law sets many limits per polymer rather than per additive: the same hindered amine light stabilizer is capped at 0.3 wt% in polypropylene and 0.2 wt% in polyethylene of density 0.94 and above, and a mould release that is allowed at 0.5 wt% in polycarbonate has no such entry elsewhere. Carbon black follows the reverse pattern, since Regulation (EU) No 10/2011 (FCM 411) caps it at 2.5 % w/w in the polymer regardless of which plastic carries it. Chimassorb 944 (CAS 70624-18-9) carries two different FDA ceilings for exactly this reason, and the full set of per-polymer limits this reference tracks sits in the compliance table further down this page.

Which Additives Does Each Polymer Need? The Polymer and Additive Matrix#

The matrix below maps 21 additive families against the polymers that use them, and each cell says whether the family is essential, optional or irrelevant for that plastic. The legend is fixed sitewide: essential means the polymer cannot be processed or used without the family; typical means the family appears in most commercial compounds; application only means it appears when the end use demands it; a dash means it is not used. Each family name links onward to the plastic additives database.

Commodity plastics: PVC, PP, PE and PS#

The four commodity plastics share fewer families than the engineering group, but their shared families carry the widest dosage ranges on the site, from a fraction of a percent of acid scavenger to 65 wt% of plasticizer in flexible PVC.

Table T2. Additive families by commodity polymer

Cells marked essential cannot be omitted without failing to process or certify the compound; application only means the family enters only when the end use requires it, such as flame retardancy in cable-grade flexible PVC or a blowing agent in expandable polystyrene. Recyclate here means restabilized r-PP and r-HDPE, not virgin resin.

Engineering and bio-based plastics#

Additives that decompose below 320 °C do not appear in the columns below, which is why aluminium trihydroxide and most ammonium polyphosphate flame retardants are absent from polyamide and polycarbonate even though both appear in the commodity table.

Table T3. Additive families by engineering and bio-based polymer

PLA and PET share hydrolysis stabilizers and chain extenders because both are step-growth polyesters that lose molecular weight the same way. ABS needs no separate impact modifier because the butadiene phase built into the resin performs that role.

Additives for Commodity Plastics#

Polyvinyl chloride, polypropylene, polyethylene and polystyrene take the largest additive volume of any polymer group, led by PVC, where more than 85 % of European plasticizer volume goes into flexible grades (European Plasticisers).

Additives for PVC#

PVC needs more additive families than any other plastic: it is about 57 % chlorine by mass and splits off hydrogen chloride from 100-120 °C, so every compound carries a heat stabilizer, and the stabilizer comes with lubricants, processing aids, impact modifiers, fillers and, in flexible grades, plasticizers.

The EU market divides PVC roughly 60 % rigid and 40 % flexible, with about 70 % of consumption going into building and construction (VinylPlus, 2023). Calcium-based stabilizers, calcium-zinc and calcium-organic systems together, now account for 83 % of EU stabilizer use, the result of a voluntary lead replacement programme the industry completed in 2015. The European Chemicals Agency's 2023 investigation into PVC assessed 63 additives used as heat stabilizers, plasticizers and flame retardants and concluded that restrictions may be needed.

Rigid PVC (PVC-U)#

Rigid PVC gets its stiffness from the polymer and its processability from the package: the PPI TR-2-2023 range composition for US pressure pipe allows a tin heat stabilizer at 0.3-1.0 phr, calcium stearate at 0.4-1.5 phr, paraffin wax at 0.6-1.5 phr, titanium dioxide at 0.5-3.0 phr and calcium carbonate up to 5.0 phr on 100 parts resin. Rigid PVC is notch-sensitive, so pipe and profile compounds add an acrylic core-shell, MBS or chlorinated polyethylene impact modifier on top of this base package. The full pipe, profile, sheet and foam formulations are covered separately in rigid PVC formulations.

Flexible PVC (PVC-P)#

Flexible PVC is defined by its plasticizer content, which runs from 5 to 65 wt% of the compound and makes flexible PVC the destination of more than 85 % of European plasticizer volume. Liquid calcium-zinc and barium-zinc stabilizers dominate flexible applications, and EU calendered film runs almost solely on barium-zinc and calcium-zinc systems rather than the tin and lead chemistries of rigid PVC. Cable insulation adds a third layer: aluminium trihydroxide and zinc borate at 3-6 phr raise the limiting oxygen index to a minimum of 26 vol% oxygen, the threshold cable compounds have to clear. The plasticizer selection, stabilizer chemistry and filler loadings for cable, film, flooring and plastisol grades are set out in full in flexible PVC formulations.

Additives for polypropylene#

Polypropylene oxidises at the tertiary carbon on every repeat unit and breaks chains as it does so, which is why an unstabilized polypropylene compound cannot be processed commercially and why the standard package starts with a phenolic antioxidant at 0.05-0.4 wt% blended with a phosphite. An acid scavenger, calcium stearate up to 1,000 ppm or hydrotalcite, neutralises catalyst residues, and nucleating and clarifying agents follow to control crystallinity and haze. Outdoor grades add a hindered amine light stabilizer with a UV absorber, while filled grades carry 20-40 % talc or calcium carbonate for stiffness and cost. Talc adsorbs antioxidant from the melt, so a talc-filled compound needs a stronger antioxidant package to reach the same service life.

Additives for polyethylene#

Polyethylene fails in the opposite direction to polypropylene: it crosslinks and forms gels rather than losing molecular weight, so its package pairs a phenolic antioxidant with a phosphite or phosphonite and adds an acid scavenger for catalyst residues. Pressure pipe grades (EN 12201-1 / ISO 4427-1) carry 2.0-2.5 wt% carbon black with a compound oxidative induction time of at least 20 minutes at 210 °C, never the 2.0-3.0 % range that belongs to geomembranes. Blown film grades carry slip additive at 500-1,200 ppm and antiblock at 2,500-10,000 ppm, plus a fluoropolymer processing aid against melt fracture. Foamed polyethylene carries azodicarbonamide at up to 5 wt% of the finished foam under 21 CFR 178.3010, a ceiling with no equivalent in pipe or film grades.

Additives for polystyrene, EPS and XPS#

Polystyrene and its foams are stabilized lightly and flame-retarded heavily: the limiting oxygen index of unmodified expanded polystyrene is about 18, while ASTM C578 requires more than 24, so insulation boards carry a polymeric brominated flame retardant. That chemistry changed once hexabromocyclododecane (HBCD) became an SVHC on 28 October 2008 and reached its REACH Annex XIV sunset on 21 August 2015, retiring the older additive in favour of the polymeric type. High-impact polystyrene takes a different route to toughness: raising the rubber content from 5 to 15 % gave 166.2 J/m of notched impact strength, about four times the 5 % grade. EPS and XPS foam are expanded with pentane or isopentane under 21 CFR 178.3010, alongside a styrene residual limit of at most 1 wt%, 0.5 % for fatty foods.

Additives for Engineering Plastics#

Every engineering polymer here processes at roughly 240-320 °C, above 340 °C for PEEK, which excludes ATH, most ammonium polyphosphate and low-molecular-weight phenolics. The shared specification set is UL 94 flammability ratings V-0 at 0.4-1.6 mm, glow-wire ignition temperature 775 °C, comparative tracking index 600 V and heat ageing from 150 to 230 °C.

Additives for nylon (polyamide)#

Polyamides are stabilized against long-term heat with copper halide systems, a chemistry patented by DuPont in 1954 that uses 0.001-0.03 wt% copper with 0.1-5 wt% of a halide, and they are reinforced with 10-50 % glass fibre. Phosphinate flame retardants add a UL 94 V-0 rating at 0.4-3.2 mm in glass-filled grades.

Additives for polycarbonate and PC/ABS#

Polycarbonate hydrolyses above 70 °C at high humidity, so it is dried before processing and formulated with UV absorbers, an internal mould release such as pentaerythritol tetrastearate at up to 0.5 wt% under 21 CFR 177.1580, and PTFE as an anti-drip agent in flame-retardant grades. A PC/ABS blend with 20 wt% aryl bisphosphate flame retardant reaches UL 94 V-0 and a heat deflection temperature of 72.6 °C.

Additives for ABS, SAN and ASA#

ABS combines 15-35 % acrylonitrile, 5-30 % butadiene and 40-60 % styrene, and the butadiene phase is what has to be protected, so the package leads with antioxidants, for example 0.2 wt% of a hindered phenol. ASA replaces that rubber with a saturated acrylate and weathers about ten times better than ABS outdoors.

Additives for PET#

PET is formulated around three problems: antimony catalyst residue, acetaldehyde, which is detectable as an off-taste in water at 10-20 ppb, and oxygen ingress, so bottle grades carry reheat additives, acetaldehyde scavengers and oxygen barriers or scavengers. Intrinsic viscosity tracks the application, 0.70-0.78 dL/g for water bottles and 0.78-0.85 dL/g for carbonated soft-drink bottles.

Additives for PBT#

PBT melts at 223 °C and is sensitive to hot water above 60 °C, so its package combines hydrolysis protection with phosphinate flame retardants, for example 18 wt% of an aluminium phosphinate for a V-0 rating.

Additives for POM (acetal)#

POM is stabilized against its own monomer: formaldehyde scavengers are part of every compound, and US food-contact copolymer grades may carry at most 2.0 wt% of stabilizers in total with no single one above 1.0 wt%. As little as 1-3 ppm of chlorine contamination causes stress cracking in POM.

Additives for PMMA (acrylic)#

PMMA transmits about 92 % of visible light through 3 mm, and the additive package exists to keep that number: UV absorbers protect the surface, and light-diffusing particles are added only where the part has to hide an LED.

Additives for high-performance polymers#

PEEK melts at 343 °C and PPS serves continuously up to about 240 °C, which leaves only additives that survive those temperatures: glass and carbon fibre, PTFE and graphite as solid lubricants, and high-temperature pigments.

Additives for Bioplastics, Elastomers and Thermosets#

Global bioplastics capacity reached 2.31 Mt in 2025, about 0.5 % of the 431 Mt of global plastics production that year (European Bioplastics and nova-Institute, 2025; PlasticsEurope, 2025); the group is held together by one rule, the additive has to be compatible with the polymer's end-of-life route.

Additives for PLA#

PLA loses molecular weight to hydrolysis and crystallises slowly, so its package is built from chain extenders at 0.1-0.5 wt%, nucleating agents, plasticizers and carbodiimide hydrolysis stabilizers. EN 13432 requires at least 90 % biodegradation in 6 months and less than 10 % residue after 3 months.

Additives for biodegradable and compostable plastics#

Compostable compounds based on PBAT, PBS, PHA and starch blends are limited by the same standard as PLA: EN 13432 sets biodegradation, disintegration, heavy-metal and ecotoxicity criteria that the additive has to pass as well as the polymer.

Additives for polyurethane and TPU#

Polyurethane is about 25 Mt a year and roughly two thirds of it is foam, so the additive content of this reference covers flame retardants, blowing agents and foam surfactants, while isocyanates, polyols and amine or tin catalysts are matrix chemistry and out of scope. The F-gas Regulation (EU) 2024/573 has banned foams with a global warming potential of 150 or more since 1 January 2023.

Additives for EVA#

EVA is defined by its vinyl acetate content, from 12 to 70 %, and its largest additive-driven use is the photovoltaic encapsulant, crosslinked with a peroxide to a gel content of 84-90 % and stabilized with a phosphite and a hindered amine.

Additives for thermoplastic elastomers#

Thermoplastic elastomers take the additive logic of both of their phases: the hard phase needs the stabilizer package of its base polymer and the soft phase needs plasticizer and antioxidant protection. Our source library carries no verified dosage figure for TPE as a class, so no level is written here.

Additives for epoxy resins and composites#

Epoxy composites are formulated with tougheners, fillers, UV stabilizers and flame retardants, while the curing agents and hardeners that build the network are matrix chemistry and are not covered here.

Plastic additives in rubber and elastomers#

Rubber shares four additive families with plastics, antioxidants, plasticizers, fillers and peroxides, and only those four are covered here: accelerators, vulcanising agents and antiozonants are rubber chemistry and sit outside the border.

Additives for Recycled Plastics#

Recycled plastics need an additive package that virgin resin does not: their stabilizers are partly consumed, so restabilization with a phenol and phosphite blend at 0.1-0.3 wt% is the first step in recycled polypropylene and recycled HDPE. That step exists because recyclate carries a lower oxidative induction time than virgin resin of the same grade, evidence of the antioxidant capacity the first life cycle already used up. Contamination between polyolefins compounds the problem: as little as 5 % polypropylene in recycled HDPE can cut slow-crack-growth resistance by up to 40 %, and polyethylene contamination in recycled polypropylene can cut the same property by up to 70 %, which is what compatibilizers control. Design for recycling decisions made at the virgin-resin stage determine how much of this restabilization work the recycler faces later.

Odour is the third recyclate-specific problem this reference tracks: melt compounding mixed polyolefin waste with 4 wt% zeolite cut average odour intensity by 45 % in a study by Garofalo and colleagues (Polymers, 2023). Recyclate is not allowed in pressurised gas or drinking-water pipe systems under existing standards. Formulators track restabilization progress with oxidative induction time (OIT), the same test that sets the pipe-grade specification for virgin polyethylene.

Recycled PVC#

Recycled PVC carries its history in its additives: lead in PVC has been restricted to below 0.1 % by weight since 29 November 2024 under REACH Annex XVII entry 63, while recovered rigid PVC may contain up to 1.5 % in listed uses until 28 May 2033, with the article marked "Contains ≥ 0,1 % lead". The equivalent derogation for recovered flexible PVC expired earlier, on 28 May 2025. The full lead limits, restabilization sequence and closed-loop condition are set out in recycled PVC.

How Much Additive Does Each Polymer Carry? phr, wt% and ppm by Polymer#

Dosage units follow the polymer: PVC and rubber formulations are written in parts per hundred resin, polyolefin and engineering compounds in weight percent or parts per million, and masterbatch users work in let-down ratios instead. The two systems convert directly: weight percent equals the phr value of one ingredient divided by the total phr of the whole formulation, multiplied by 100. The PPI TR-2-2023 pressure-pipe example works out the conversion in practice: a tin heat stabilizer dosed at 0.70 phr in a formulation that totals 108.03 phr comes out to 0.65 wt% of the finished compound, because the resin itself is only 100 of those 108.03 parts. PHR (parts per hundred resin) as a unit only makes sense once the full formulation total, filler and pigment included, is known, which is why PVC and rubber datasheets always state a formulation total alongside the individual dosages. Masterbatch users skip both units for a let-down ratio instead: a carbon black masterbatch compounded at 35 % carbon black and let down at 5-6.5 % delivers about 1.75-2.3 % carbon black in the finished compound, close to the 2.0-2.5 wt% pipe specification without the processor ever weighing carbon black directly.

Table T4. Dosage unit and typical additive load by polymer

Loads are compound values from our source library, not recommendations; the polymer guide gives the context for each.

Compliance Limits That Are Written per Polymer#

Food-contact law limits additives by polymer as often as by substance: carbon black is capped at 2.5 % by weight of the polymer in the EU, a mould release at 0.5 wt% in polycarbonate in the US, and azodicarbonamide at 5 wt% of finished foamed polyethylene. EU 10/2011, Regulation (EU) No 10/2011 on plastic materials and articles intended to come into contact with food, sets the carbon black limit at FCM 411 and the antimony specific migration limit for PET at 0.04 mg/kg under its Annex II. It also caps organoclay FCM 1030 at 12 % w/w in polyolefins for dry food contact at room temperature and organoclay FCM 1075 at 4.0 % w/w when the host polymer is PLA used for water storage, limits that exist only because of what the container holds. On the US side, 21 CFR 177.1520 sets the olefin-polymer specifications a resin has to meet before its additives are considered, including a maximum of 6.4 % n-hexane extractables for polypropylene and 5.5 % for polyethylene at 50 °C, and 21 CFR 177.1580 carries the polycarbonate mould-release limit.

Table T5. Additive limits written per polymer

FDA limits are legal maxima, not recommended dosages, and this reference never writes a substance as "FDA approved"; the agency clears a use under a specific regulation or food-contact notification, not a product. The FDA food contact rules that set every US limit above work the same way.

How to Build an Additive Package for Your Polymer#

Building a package starts from the polymer, not from the additive: the degradation mode fixes the stabilizer, the processing window fixes the lubricant and processing-aid package, and only then does the end use decide the functional families.

1. Identify the polymer and its sub-type, PVC-U or PVC-P, PA6 or PA66, homopolymer or copolymer POM, since the sub-type changes both the degradation mode and the legal limits that apply.
2. Add the mandatory stabilizer for that degradation mode: a heat stabilizer for PVC, an antioxidant and phosphite for polyolefins, or a copper halide system for polyamide.
3. Build the processing package the melt window demands: lubricants and processing aids for a narrow window such as PVC, none at all for a wide one such as polyethylene film.
4. Add the functional families the end use requires: flame retardants for cable, UV stabilizers for outdoor parts, slip and antiblock for film.
5. Check the per-polymer legal limit before fixing the final dosage, since a level safe in one polymer can exceed the limit written for another.

The full procedure is set out in how to select plastic additives; a companion selection worksheet turns the five steps above into a fillable checklist. Once a package is chosen on paper, plastic compounding covers how it is mixed into the resin at production scale.

Find the additive families for your polymer and function with the additive finder by polymer and function, launching soon.

─────

What the Polymer Decides About Migration, Recycling and Exposure#

What leaves a plastic depends on the polymer as much as on the additive: a slip agent is chosen because it blooms to a polyethylene film surface within 24 to 48 hours, while a polymeric hindered amine is chosen for the opposite reason. Blooming is deliberate for some families and a failure mode for others: erucamide migrates to the surface of a polyethylene film by design, reaching its final coefficient of friction after 7 to 10 days, while the same behaviour in a plasticizer is what regulators write exposure limits against. The EU sets an overall migration limit of 10 mg per square decimetre for food-contact plastics, or 60 mg/kg for articles intended for infants. Additive migration is therefore a property of the polymer and additive together, never of the additive alone.

Legacy additives in recycled polymers#

Recycled streams carry the additives of the products they came from, which is why lead and ortho-phthalates still appear in recovered PVC and brominated flame retardants in recovered styrenics. Wiesinger and colleagues at ETH Zurich (2024) tested 151 Swiss PVC flooring samples and found that 16 % carried a regulated chemical, mainly lead or DEHP, above the 0.1 wt% threshold, while 29 % carried another ortho-phthalate above the same threshold. Both mechanisms are collected in legacy additives in recycled plastic.

Polymer properties this reference does not cover#

This reference covers additives for plastics, not polymer science: how a polymer is made, what tensile strength or Shore hardness mean, and which resin code a container carries are outside its scope. It also excludes uses that share the vocabulary but not the border: concrete and grout admixtures, paints and coatings, adhesives, fuel and lubricant additives, and food additives. Full definitions sit in the plastic additives glossary.

Request quotes for the additives in your package from verified suppliers through the plastic additive supplier finder, filterable by polymer, family, volume and country.

The companies behind every family in this index are listed in the plastic additive manufacturers and suppliers directory.

---