Description
Multibond SMX25 is a high-quality, neutral, elastic 1-component joint sealant based on SMX-Polymer, built for expansion and connection joints across the building industry — sealing joints in prefabricated buildings, between window and door frames, and other genuine movement joints. Being phthalate-free and free of solvents, halogens, acids and isocyanates makes it a genuinely lower-hazard sealant to work with compared with older sealant chemistries.
Its primerless application on most substrates (except where water pressure may occur) is a real time-saver on site, removing a preparation step that many sealants require. Staying elastic after curing, with no bubble formation even in high temperature and humidity conditions, means it holds up reliably in genuinely demanding installation environments rather than only performing well under lab conditions.
Its phthalate-free, solvent-free and isocyanate-free formulation also means Multibond SMX25 avoids several of the strongest odours and health precautions associated with older polyurethane and solvent-based sealants, without giving up the elasticity or adhesion needed for a genuine structural or expansion joint. The primerless application across most common building materials is a real time saver on site, letting a single cartridge move between substrates without a separate priming step for each one.
Technical Specifications
| Basis | SMX Hybrid Polymer |
|---|---|
| Skin formation | Approx. 15 min (23°C/50% RH) |
| Curing speed | 3mm/24h (23°C/50% RH) |
| Hardness | 25 ± 5 Shore A |
| Maximum allowed distortion | ±25% |
| Elongation at break | >500% |
| Temperature resistance | -40°C to +90°C (cured) |
| Application temperature | 5°C to 35°C |
| Colours | Concrete grey, beige, dark grey, white, old white, black, sandstone, anemone, more on request |
| Packaging | 600ml sausage |
Where to Use
- Expansion and connection joints in prefabricated buildings
- Sealing between window and door frames
- Joints needing overpainting with water-based paints and varnishes
How to Apply
- Prepare the joint — ensure it is rigid, clean, dry and free of dust and grease.
- Apply without primer — extrude the sealant directly onto most substrates (except where water pressure may occur).
- Tool the joint — smooth to shape before skin formation begins (approx. 15 minutes).
- Allow to cure — respect the 3mm/24h curing speed before further work.
- Paint if required — overpaint with water-based systems once fully cured.
Important Notes
- Good resistance to salt water, aliphatic solvents, hydrocarbons and diluted mineral acids and alkalis.
- Poor resistance to aromatic solvents, concentrated acids and chlorinated hydrocarbons.
- Store for 12 months in unopened packaging, +5°C to +25°C.
