Silicones, silicone oils, sprays
Casting and potting resins
Internal Reference:
92-ST40.KT.ML290.GR
HS Code:
3214.1000
Technical Data
Typical values, not a specification. The technical data sheet (TDS) is binding.
Product Information
- Tensile Strength
- approx. 2.0 N/mm²
- Temperature range (°C)
- -40 °C to +90 °C
- Container
- 290ml cartridge
- Consistency
- Pasty, sprayable
Performance at Full Cure
- Elongation at break
- approx. 250%
Physical Properties
- Density
- 1.38 g/cm³
- Hardness (Shore A)
- approx. 35
- Chemical group
- Silane-modified polymer
- Color
- grau
- Cured layer thickness after 24 hours
- approx. 2.0 mm
- Curing technology
- Moisture curing
Features
- Processing temperature
- +5 °C to +40 °C
- Stress at 100% elongation
- approx. 1.1 N/mm²
- Volume change
- ≤ 6%
- Number of components
- 1K
Product Description
Merbenit ST40 is a sprayable 1K-SMP adhesive/sealant for large-area bonding and seam sealing — Plastisol appearance, long open time (25 min), Shore A 35.
Silane-modified polymers (SMP) are modern high-performance adhesives — moisture-curing, solvent-free, isocyanate-free, and silicone-free, with a very broad adhesion spectrum on metals, painted and galvanized surfaces, engineering plastics, glass, ceramics, concrete, stone, and wood. Paint-compatible, corrosion-protective, shock- and vibration-resistant, low-odor. ST40 is a specific variant of the Merbenit SMP series — the most important properties and applications are listed below.
Merbenit ST40 is designed for large-area applications — sprayable, with a long processing time (25 min) for demanding seam sealing. The finished seam seals are visually identical to classic plastisol seams — ideal as a replacement for plastisol in automotive manufacturing.
What sets ST40 apart
What is ST40 used for?
Processing
Recommended accessories
ST40 compared with related Merbenit products
Direct comparison of mechanical and processing values — all data from the official Merbenit TDS.
ST40 Current Product |
HM21 → | HT50 → | TMS32 → | |
|---|---|---|---|---|
| Crosslinking system | 1K moisture-curing | 1K moisture-curing | 1K moisture-curing | 1K moisture-curing |
| Consistency | pasty, sprayable | Non-sagging, ≤3 mm | non-sag | Non-sagging, ≤3 mm |
| Shore A hardness | A 35 | A 45 | A 45 | A 34 |
| Tensile Strength | 2.0 N/mm² | 2.5 N/mm² | 2.5 N/mm² | 1.6 N/mm² |
| Elongation at break | 250 % | 350 % | 200 % | 500 % |
| Modulus 100% | 1.1 N/mm² | 1.6 N/mm² | 1.5 N/mm² | 0.8 N/mm² |
| Processing time | 25 min | 30 min | 10 min | 30 min |
| Through-curing 24 h | 2.0 mm | ≥3.0 mm | 2.5 mm | ≥2.0 mm |
| Through-cure 48 h | 3.0 mm | ≥4.0 mm | 4.0 mm | ≥3.5 mm |
| Density | 1.38 | 1.52 | 1.48 | 1.48 |
| Temperature range | –40 / +90 °C | –40 / +90 °C | –40 / +90 °C | –40 / +90 °C |
| Volume change | ≤6 % | ≤5 % | ≤4 % | ≤3 % |
| Main application | Automotive seam sealing | Metal construction | Immediate-bonding applications | Natural stone joint sealing |
Frequently Asked Questions about ST40
Practical application and design questions — answered by SILITECH.
Merbenit ST40: Sprayable 1K-SMP adhesive/sealant for large-area bonding and seam sealing — Plastisol appearance, long open time (25 min), Shore A 35. Main applications: Automotive seam sealing, weld seam protection, large-area bonding.
SMP = Silane-modified polymer. This modern adhesive class combines the advantages of silicone (elasticity, weather resistance, broad adhesion spectrum) and polyurethane (mechanical strength, paint compatibility) — without their disadvantages (silicone: not paintable, corrosion on some metals; PU: isocyanates, often problematic indoors). SMP adhesives are solvent-free, isocyanate-free, and silicone-free, paint-compatible, corrosion-protective, and adhere without primer to most substrates — except PE, PP, PTFE, and silicones.
ST40 adheres to metals (aluminum, stainless steel, steel), powder-coated and painted surfaces, galvanized/anodized/chromated/zinc-coated substrates, many plastics, ceramics, stone, concrete, render, wood, and glass. Not suitable for: PP, PE, PTFE (Teflon), silicones, and bituminous substrates. For critical material combinations, we recommend a preliminary test or the use of a primer (V40 for smooth, V21 for absorbent substrates).
Store in unopened original container in a dry, cool place — typically between +5 and +30 °C. Consult the safety data sheet (SDS) before use. Observe the expiry date on the packaging. Process opened cartridges promptly — skin formation in the nozzle will block further application.
In the comparison table above, you will find related Merbenit products with different properties — different hardness, pot life, elongation at break, or special certifications (IMO, EN 45545-2, FMVSS 212, ISEGA, Minergie-ECO). If you are unsure about the optimal choice, we will be happy to advise you — contact SILITECH with your specific application (substrate pairing, desired hardness, processing workflow, certification requirement).