Wacker Catalyst T 37® – Hardener for ELASTOSIL® M Condensation Silicones & Mold Making

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Wacker

Wacker Catalyst T 37® – Hardener for ELASTOSIL® M Condensation Silicones & Mold Making

✔ 3-4% dosage
✔ dry, stretchy result
✔ Can be used neat or mixed
✔ Low shrinkage (< 0.3%)
✔ More resistant to PU and Epoxy
✔ Mixing ratio (Weight)100:5
✔ Long processing time Read more

€5,95 Incl. BTW

SKU: S11636

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50 gram bottle of WACKER® Catalyst T-37
250 gram bottle of WACKER® Catalyst T-37
800grams bottle WACKER® Catalyst T-37

50 gram bottle of WACKER® Catalyst T-37

€5,95

250 gram bottle of WACKER® Catalyst T-37

€20,95

800grams bottle WACKER® Catalyst T-37

€50,95

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✔ 3-4% dosage
✔ dry, stretchy result
✔ Can be used neat or mixed
✔ Low shrinkage (< 0.3%)
✔ More resistant to PU and Epoxy
✔ Mixing ratio (Weight)100:5
✔ Long processing time

Premium Tin Catalyst Hardener for Professional Condensation Silicone and Mold Making Applications

Wacker® Catalyst T 37 is the standard hardener (B-component) for condensation-curing ELASTOSIL® M silicone rubbers, including M 4400, M 4440, and M 4470. It is a colorless, low-viscosity tin catalyst with a density of 0.94 g/cm³ and a viscosity of approximately 2 mPa·s. T 37 is distinguished by the excellent resistance it imparts to the cured silicone against polyurethane casting resins, increasing the number of castings per mold. The standard dosage is 3 to 4% by weight of the A-component: at 3%, you achieve a working time of approximately 80–100 minutes and a curing time of 10–12 hours; at 4%, this shortens to 50–70 minutes working time and 8–10 hours curing time. Less hardener prolongs the curing time and gives air bubbles more time to escape; more hardener accelerates curing but increases shrinkage and aging of the mold.

Key Benefits

Dosage 3–4% by weight – precisely adjustable working and curing time as desired.
Density 0.94 g/cm³ – low-viscosity catalyst (approx. 2 mPa·s) that can be easily and uniformly mixed in.
Pot life 80–100 minutes at 3% – ample working time for large and complex molds.
High polyurethane resistance – significantly increases the number of castings with polyurethane casting resins.
Flash point 70 °C – for safe processing under normal workshop conditions.
Mixable with fast catalyst – can be combined with T 47 to further accelerate the curing speed.

Typical Applications

Hardener for ELASTOSIL® M 4400, M 4440, and M 4470 condensation silicones.
Mold making for casting polyurethane and polyester resins.
Reproduction of statues, ornaments, and decorative elements.
Art casting, model making, and prop and set construction.
Mixing with other Wacker T-catalysts for a desired curing speed.

Processing Instructions

Stir the condensation silicone (A-component) thoroughly in its packaging before use.
Weigh out Catalyst T 37 by weight: 3 to 4 grams per 100 grams of A-component. Less hardener prolongs curing time, more hardener accelerates it but increases shrinkage.
Mix A and B components slowly and thoroughly until a homogeneous mixture is achieved; scrape the sides and bottom of the mixing container.
Process the mixture within the pot life and never prepare more than you can process within that time.
Allow the silicone to fully cure according to the specifications of the chosen ELASTOSIL® M product before demolding.

Please note: pot life and curing time are highly dependent on the mixing ratio and humidity. With more hardener or higher humidity, both will be shorter.

Wacker Chemie AG is a world market leader in the development and production of silicones for industrial and technical applications.

Professional Support

Not sure which catalyst or dosage is right for your silicone and desired processing time? Our specialists will gladly advise you on the correct choice and possible combinations with other Wacker T-catalysts. Feel free to contact us.

Safety Information

Wacker Catalyst T 37 is classified as hazardous (GHS08, health hazard) and contains an organotin compound. The relevant hazard statements are H373 (may cause damage to organs through prolonged or repeated exposure) and H413 (may cause long-lasting harmful effects to aquatic life). Avoid breathing vapor or spray and prevent release to the environment. The product is flammable with a flash point of approximately 70 degrees Celsius; keep it away from heat and ignition sources. When processing, wear suitable protective gloves made of butyl rubber, close-fitting safety glasses (EN 166), and protective clothing. Ensure good ventilation and extraction. When atomizing or forming aerosols, use a respiratory mask with an ABEK or ABEK-P2 filter. Do not eat, drink, or smoke while working, and wash hands thoroughly after use. For complete information, always consult the Safety Data Sheet (SDS) for Wacker Catalyst T 37.

Safety Pictograms	Safety Data Sheets (SDS)
	📥 EN SDS WACKER CATALYST T 37

Signal Word	H‑code	Hazard Statement	P‑codes	P‑statements
Warning	H373	May cause damage to organs through prolonged or repeated exposure	P260 P501	Do not breathe dust/fume/gas/mist/vapours/spray Dispose of contents/container in accordance with local regulations

More information about H and P statements: UK HSE &ECHA

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What is the delivery time of my order?

Orders placed and paid for on business days will be shipped on the same day in most cases. Orders received on weekends will be processed on the next business day.

We always do our best to ship orders as quickly as possible, but actual shipping times may vary due to high volume, stock availability, or carrier circumstances.

Delivery time depends on the destination country and the carrier. Below is a general indication:

Netherlands: usually within 1 business day
Belgium & Germany: typically within 1–2 business days
Other countries: depends on the destination and the local carrier

Please note: these are guidelines, not guarantees. The final delivery time may differ due to factors beyond our control, such as sorting center delays, public holidays, or exceptionally high volume.

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Wacker Catalyst T 37® – Hardener for ELASTOSIL® M Condensation Silicones & Mold Making

Wacker Catalyst T 37® – Hardener for ELASTOSIL® M Condensation Silicones & Mold Making

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