![Bis[3-(triethoxysilyl)propyl] tetrasulfide (TESPT) · PubChem chemical identity reference. Confirm commercial form, composition and application grade separately.](/wp-content/uploads/2026/11/envo-a027.webp)
Plan a trial for your application
Silica-filled tire compounds
At equal filler and mixing conditions, compare dispersion, cure curve and dynamic properties.
Evaluating carrier-based substitutes
Calculate addition on active silane content and subtract the corresponding carrier from the formulation.
Purchase specifications and incoming inspection
Review these properties when selecting and inspecting incoming material. Example figures refer to the cited grade or source. Confirm the offered specification, packaging and lead time in the quotation. Evonik Si 69 · Sulfur-containing silane for rubber ↗
| Property | Unit | Published or agreed specification | Test conditions and checks |
|---|---|---|---|
| Active silane | % by mass | Confirm against the offered grade and purchase specification | Distinguish neat, carrier-based and blended products. |
| Total sulfur | % by mass | Confirm against the offered grade and purchase specification | Record the supplier’s description of the sulphur-chain distribution in the product. |
| Volatiles or free alcohol | % by mass | Confirm against the offered grade and purchase specification | Confirm the test method against the specification for the offered grade. |
When approving a sample, record the grade, methods, limits and specification revision. On receipt, match the packing lot number to the lot-specific COA and record the measured values and release decision.
From samples to commercial delivery
Packaging and receiving
Check drum material and seals for liquids. For carrier-based solids confirm net weight and declared active fraction.
Storage and handling
Follow supplier moisture-control instructions. Record opening date and exposure to high transit temperatures.
Sample and order lead times
State the finished part, machine trial quantity and routine order size. Match trial and commercial grades and agree MOQ, load unit, lead-time start and arrival.
Questions from the plant
Can TESPT and TESPD be substituted at equal weight?
Check sulphur-chain characteristics and the cure system. Verify processing safety in the same formulation.
Why do white agglomerates remain after adding silane?
Check filler moisture, dispersion and mixing temperature and time against a reference compound.
Report a delivery or batch issue
Include the order number, lot number from the package, label photos and inspection records for the affected lot. When retesting, check Active silane, Total sulfur, Volatiles or free alcohol.
Request documents for your application
TDS · Technical data sheet
For grade selection and sample approval, specify the grade and revision required.
SDS · Safety data sheet
Specify the country or region of use and the required language.
COA · Certificate of analysis
Request a sample COA during supplier review. For incoming inspection, provide the actual lot number.