Performance Characteristics:
•Solvent-free, odorless and isocyanate-free, eco-friendly
•The cured adhesive is crystal clear and paintable, preserving the original appearance of substrates
•Waterproof, anti-mildew and anti-yellowing
•One-component for easy application, offering good extrudability and thixotropy between 5℃ and 40℃
SMT-351 is a one-component, moisture-curing silane-modified polyether mold-resistant sealant. This solvent-free sealant features anti-staining performance and eco-friendly formula, delivering superior adhesion to most construction substrates. Specially developed for mold-proof sealing applications, it maintains long-term waterproof and anti-mildew performance. It is particularly suitable for bonding and sealing in mold-prone humid environments such as kitchens and bathrooms. It generates no irritating or unpleasant odors during application, bringing brand-new construction experience and aesthetic finishing effects.
Application Areas
- Ideal for invisible bonding and sealing applications such as display cabinets, crystal glass blocks, jewelry display stands, optical components and electronic parts
Package
- This product is available in standard 300ml rigid cartridges (24 pieces per carton) and 600ml soft sausage packs (20 pieces per carton). Custom filling specifications can be provided upon customer request.
| Test Items | Technical requirements | Typical Data | Test Method |
|---|---|---|---|
| Appearance | Smooth and uniform paste, free of bubbles, skinning and gel lumps | Smooth and uniform paste, free of bubbles, skinning and gel lumps | Visual inspection |
| Density, g/cm³ | 1.03±0.03 | 1.03 | GB/T 13477.2-2018 |
| Sag Resistance, vertical, mm | ≤3 | 0 | GB/T 14683-2017 |
| Tack-free time, min | 3-10 | 3 | GB/T 13477.5 |
| Cure rate, mm/24h | ≥2.5 | 3.0 | GB/T 13477.22 |
| Tensile Strength, MPa | ≥1.5 | 2.5 | GB/T 528-2009 |
| Elongation at Break, % | ≥200 | 250 | |
| Hardness, Shore A | 35-45 | 40 | GB/T 39693.4-2025 |
Before application:
- Prior to application, compatibility tests between the sealant and contacting materials as well as adhesion tests on the substrates to be bonded shall be carried out.
Construction Method:
- All application surfaces must be clean, dry and free of contaminants.
- Fit the cartridge into a suitable caulking gun. Cut the nozzle according to joint width, then extrude sealant into the joint to ensure full contact between sealant and joint edges.
- Compact the sealant with a proper tool and scrape off excess material.
- Not suitable for locations with long-term service temperature above 100℃.
- Do not apply when the substrate surface temperature is lower than 5℃ or higher than 40℃.
- Unsuitable for substrates that exude grease, plasticizers or solvents, such as oil-impregnated wood surfaces.
- Not applicable to areas under continuous water immersion or permanently high humidity.
- Not recommended for bonding polypropylene (PP), polyethylene (PE) and polytetrafluoroethylene (PTFE).
- The application surface must be clean, dry and free of contaminants.
- Use within the shelf life; expired products are forbidden to use.
- Construction shall be performed strictly in accordance with adhesion test procedures.
- Avoid direct contact with skin and eyes; do not ingest.
- Keep out of reach of children.
- Trace amounts of chemical substances will be released during curing. Sufficient ventilation must be maintained at the working area; the cured sealant is non-toxic to human bodies.
