Heat-aging synergist
With a phenolic antioxidant it extends oven-aging life far beyond either component alone.
SUNNOX® DSTDP
DSTDP Thioester Antioxidant Supplier
SUNNOX® DSTDP (distearyl thiodipropionate) is a thioester secondary antioxidant with low volatility. Combined with a phenolic primary, it extends the heat-aging life of polyolefins, ABS and rubber.
CAS 693-36-7 · Thioester · Secondary antioxidant
- Lot COA with every shipment
- Samples for your trials
- Technical support for your trial
Product overview & key benefits
DSTDP decomposes hydroperoxides during long service at elevated temperature and works in strong synergy with hindered phenols such as 1010. Its longer alkyl chains give a higher melting point (63–69 °C) and lower volatility than DLTDP, which suits higher processing temperatures and parts that stay hot in use.
Lower volatility
Higher molecular weight than DLTDP, so less is lost at high processing temperatures.
Proven in polyolefins
Widely used in PP and PE parts for appliances, automotive and pipe.
Technical specifications
| Parameter | Typical value |
|---|---|
| Product Name | Antioxidant DSTDP |
| Brand | SUNNOX® DSTDP |
| CAS No. | 693-36-7 |
| Chemical Name | Distearyl 3,3'-thiodipropionate |
| Molecular Formula | C42H82O4S |
| Molecular Weight | 683.2 |
| Appearance | White powder or flake |
| Melting Point | 63–69 °C |
| Acid Value | ≤0.05 mg KOH/g |
| Volatile Matter | ≤0.05% |
Typical specification. Every shipment is supplied with a batch COA; the limits that apply to your order are confirmed in the quotation and contract.
Applications by Polymer
Pick an application to see how DSTDP is normally used and what to confirm before your trial.
Polyolefins
Used with 1010 in PP and PE parts with long heat-aging requirements. Ratio and loading depend on the polymer, process and the rest of your formulation — confirm them in your own trial.
Check before trial
- Heat-aging test (temperature, hours)
- Phenolic antioxidant and level
- Odor requirements
ABS & Styrenics
Improves long-term heat stability of ABS and HIPS with a phenolic antioxidant.
Check before trial
- Grade and other additives
- Service temperature
- Color target
Rubber & Adhesives
Used as a heat-aging synergist in rubber compounds and adhesives.
Check before trial
- Base polymer
- Cure and service temperature
- Existing antioxidant package
Selection & comparison
Selecting an Antioxidant System
| Your requirement | What usually works |
|---|---|
| Color and melt-flow stability during extrusion or molding | Phosphite secondary antioxidant (168) with a phenolic primary |
| Long-term heat aging in service | High-MW phenolic primary (1010), often with a thioester (DLTDP / DSTDP) |
| Thin film, fiber, low-melting compounding | Lower-melting phenolic (1076) for easy dispersion |
| Repeated processing / recycled content | Raise the phosphite share in the blend and check yellowing after each pass |
| Humid storage or long transit | Hydrolysis-resistant phosphite such as 168; keep bags sealed |
| Food-contact articles | Ask us for grade-specific regulatory documents before trials. |
| Replacing an existing grade | Provide your current grade, TDS or specification for review. |
Antioxidant Comparison
Swipe or scroll horizontally to see all columns →
| Product | Type | Mol. weight | Melting point | Main job | Starting level |
|---|---|---|---|---|---|
| SUNNOX® DSTDP | Thioester · secondary | 683.2 | 63–69 °C | Heat-aging synergist, lower volatility | Set in your trial |
| SUNNOX® DLTDP | Thioester · secondary | 514.8 | 38–42 °C | Heat-aging synergist | Set in your trial |
| SUNNOX® 1010 | Hindered phenol · primary | 1177.6 | 110–125 °C | Long-term thermal protection | Set in your trial |
| SUNNOX® 1076 | Hindered phenol · primary | 530.9 | 50–55 °C | Long-term protection, easy dispersion | Set in your trial |
| SUNNOX® DTDTP | Thioester · secondary | 542.9 | Liquid | Heat-aging synergist, pourable | Set in your trial |
*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.
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
Regular grades are usually in stock. For large volumes, lead time is confirmed in the quotation. We quote FOB and CIF.
From first email to approved supply
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 primary + secondary package
Most polyolefin packages combine a phenolic primary with a secondary antioxidant. Change one variable at a time in your trial.
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.
Tell us your requirement. We match the grade.
Start with your polymer, quantity and destination. Add your current grade or specification and we will quote against it.
| Information | Example |
|---|---|
| Polymer / Material | PP, PE, ABS, compound, masterbatch |
| Application | Injection molding, extrusion, film, fiber |
| Current additive | Grade or supplier you use today |
| Required specification | Your TDS, COA or key limits |
| Quantity | Trial order / monthly / annual volume |
| Packaging | Standard 25 kg or specific requirement |
| Destination | Country and port |
| Documents needed | COA, SDS, REACH, food-contact statement |
Related products
SUNNOX® DLTDP
Thioester secondary antioxidant that boosts long-term heat aging when used with a phenolic.
View product →SUNNOX® 1010
High-MW hindered phenolic primary antioxidant for long-term thermal protection with low volatility.
View product →SUNNOX® 1076
Low-melting hindered phenolic primary antioxidant, easy to disperse in film and compounding.
View product →SUNNOX® DTDTP
Liquid thioester synergist for ABS, PP and adhesives where a pourable additive is easier to dose.
View product →Antioxidant DSTDP FAQ
DSTDP or DLTDP?
Choose DSTDP for higher processing temperatures and lower volatility; choose DLTDP when you need easy dispersion at low temperature.
What ratio with 1010?
There is no single ratio — it depends on the polymer, the heat-aging target and the rest of the package. Confirm it in your own oven-aging test.
Can I use DSTDP with HALS?
Thioesters can reduce HALS efficiency in outdoor applications, so check the complete package with an outdoor-aging test before you change it.
Can I get a sample before ordering?
Yes. Free samples are available for buyers evaluating the product for production use. Shipping cost is agreed case by case, and each sample comes with a COA.
What if a COA does not match our agreed specification?
Send the agreed specification and the COA showing the difference, including parameter, unit and test method, for review.
