Antioxidant 9228 High-Performance Phosphite Supplier

SUNNOX® 9228 is a high-performance diphosphite secondary antioxidant. It gives excellent color and melt stability at high processing temperatures with very good hydrolysis resistance and low volatility.

CAS 154862-43-8 · Diphosphite · Secondary antioxidant
Illustration of polymer pellets, molded samples and film
Application illustration — not a photograph of the product

Product Overview

Antioxidant 9228 (bis(2,4-dicumylphenyl) pentaerythritol diphosphite) is a solid white powder with a molecular weight of about 853 and a melting point of at least 225 °C. Its high phosphorus efficiency and hydrolysis resistance make it a step up from 168 for demanding processing such as thin-wall molding, film, fiber and engineering plastics, used together with a phenolic primary.

Typical specification. Every shipment is supplied with a batch COA; the limits that apply to your order are confirmed in the quotation and contract.

Key Benefits

High-temperature color

Keeps color and melt flow stable at high processing temperatures.

Hydrolysis resistant

Stays active and free-flowing in humid storage, unlike many diphosphites.

Efficient

High phosphorus efficiency often allows lower loading than standard phosphites.

Technical Specifications

Typical specification. Every shipment is supplied with a batch COA; the limits that apply to your order are confirmed in the quotation and contract.

ParameterTypical value
Product NameAntioxidant 9228
BrandSUNNOX® 9228
CAS No.154862-43-8
Chemical NameBis(2,4-dicumylphenyl) pentaerythritol diphosphite
Molecular FormulaC53H58O6P2
Molecular Weight853.0
AppearanceWhite powder
Melting Point≥225 °C
Volatile Matter≤0.5%

Applications by Polymer

Pick an application to see how 9228 is normally used and what to confirm before your trial.

Illustration of polymer film, molded components and masterbatch granules
Polymer application illustration

Polyolefins

Processing stabilizer for PP and PE film, fiber and thin-wall molding, with a phenolic antioxidant.

What to confirm for your application

  • Resin grade and process (film, fiber, molding, pipe)
  • Processing temperature and number of passes
  • Current antioxidant package and dosage
Discuss this application →

PC, PET & Engineering Plastics

Color and melt stability at the high temperatures these polymers need.

What to confirm for your application

  • Polymer type
  • Processing temperature
  • Color target
Discuss this application →

Polyamide

Used with an amide phenolic such as 1098 for processing color in nylon.

What to confirm for your application

  • PA type and filler
  • Processing temperature
  • Color target
Discuss this application →

Packaging & Storage

Packaging

25 kg net bags or cartons with a PE inner liner. Palletized; private-label packing on request.

Storage

Keep sealed in a cool, dry, ventilated place away from heat and direct sun. See the SDS for full handling details.

Lead time & terms

Typically 3–15 business days from order confirmation, depending on quantity. FOB, CIF or DAP to major ports.

Technical & Buying Information

Selecting an Antioxidant System

Your requirementWhat usually works
Color and melt-flow stability during extrusion or moldingPhosphite secondary antioxidant (168) with a phenolic primary
Long-term heat aging in serviceHigh-MW phenolic primary (1010), often with a thioester (DLTDP / DSTDP)
Thin film, fiber, low-melting compoundingLower-melting phenolic (1076) for easy dispersion
Repeated processing / recycled contentRaise the phosphite share in the blend and check yellowing after each pass
Humid storage or long transitHydrolysis-resistant phosphite such as 168; keep bags sealed
Food-contact articlesAsk for the grade-specific food-contact statement before trials
Replacing an existing gradeSend your current TDS or COA; we match on the parameters you approve

Antioxidant Comparison

Swipe or scroll horizontally to see all columns →

ProductTypeMol. weightMelting pointMain jobTypical starting level*
SUNNOX® 9228Diphosphite · secondary853.0≥225 °CHigh-temperature processing, hydrolysis resistance0.05–0.2% with a phenolic
SUNNOX® 168Phosphite · secondary646.9183–187 °CProcessing stability, color0.05–0.2% with a phenolic
SUNNOX® PEP-36Diphosphite · secondary632.7≥235 °CColor and melt stability0.05–0.2% with a phenolic
SUNNOX® 1010Hindered phenol · primary1177.6110–125 °CLong-term thermal protection0.05–0.3%
SUNNOX® 1098Hindered phenol · amide636.9156–161 °CPolyamide and fiber stabilization0.1–0.5%

*Starting points for trials, not fixed recommendations. The right level depends on resin, catalyst residue, processing temperature and service life. Primary and secondary antioxidants do different jobs and are not interchangeable.

Documents & Quality

COA — Certificate of Analysis

Issued for every batch shipped, with the test results for that lot.

TDS — Technical Data Sheet

Typical properties and specification for evaluation and supplier approval.

SDS — Safety Data Sheet

GHS-format handling, storage and transport information.

Samples

Lab samples for evaluation; tell us the test you plan to run so the sample size fits.

Third-party testing

SGS or Intertek testing can be arranged on request.

Regulatory statements

REACH, food-contact and other statements are issued per grade and destination; ask before ordering.

Antioxidant 9228 Buyer Guide

Name the failure you want to prevent

Yellowing or melt-flow change during processing points to the phosphite share; embrittlement or cracking after months in service points to the phenolic and thioester share. Note recycled content and the number of extrusion passes.

Start from a proven blend

Most polyolefin packages start from a phenolic primary plus a phosphite secondary, then adjust. Send your current package and we suggest a starting blend for the trial instead of changing several variables at once.

Compare the numbers that matter

For powders: assay, melting range, volatiles and light transmittance at 425/500 nm (a direct read on color). Ask for the same parameters on our COA that appear on your incoming-inspection sheet.

Lock in supply terms

Agree packaging, monthly volume, destination port and required documents up front. A matching CAS number alone does not qualify a new source; run your trial and keep the approved lot COA as the reference.

Request a Quotation for Antioxidant 9228

Start with your polymer, quantity and destination. Add your current grade or specification and we will quote against it.

InformationExample
Polymer / MaterialPP, PE, ABS, compound, masterbatch
ApplicationInjection molding, extrusion, film, fiber
Current additiveGrade or supplier you use today
Required specificationYour TDS, COA or key limits
QuantityTrial order / monthly / annual volume
PackagingStandard 25 kg or specific requirement
DestinationCountry and port
Documents neededCOA, SDS, REACH, food-contact statement
Send RFQ by EmailContact SUNCHEM →

Related Antioxidants

SUNNOX® 168

Hydrolysis-resistant phosphite secondary antioxidant for color and melt-flow protection during processing.

View product →

SUNNOX® PEP-36

Pentaerythritol diphosphite for color and melt stability in polyolefins and styrenics.

View product →

SUNNOX® 1010

High-MW hindered phenolic primary antioxidant for long-term thermal protection with low volatility.

View product →

SUNNOX® 1098

Amide-type phenolic antioxidant built for polyamides and fiber, with good color during processing.

View product →

Antioxidant 9228 FAQ

When should I upgrade from 168 to 9228?

When processing temperature, multiple passes or color requirements push 168 to its limit, or when you need lower total loading.

Is 9228 a liquid?

No. It is a white powder with a melting point of at least 225 °C.

Does it need a phenolic antioxidant?

Yes. Like all phosphites it protects mainly during processing; use it with a phenolic primary for long-term protection.

Can I get a sample before ordering?

Yes. Tell us the polymer, the test you plan to run and the quantity you need. Samples ship with a COA so you can compare the lot against your current material.

What if a COA does not match our agreed specification?

Send us the agreed specification and the COA showing the difference (parameter, unit and test method). We check it with the production batch record before you accept the material, and replace or re-test where the lot is out of specification.

Discuss Your Antioxidant 9228 Requirements

Send your application, specification and quantity to request a quotation or supporting documents.

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