LP-PU MS500
High-Performance Modified Silane (MS) Polymer Joint Sealant
Movement Capability: ±25% |
Chemistry: Isocyanate-Free MS Polymer |
Standards: ASTM C920 / EN 15651-1
LP-PU MS500 is a premium, single-component modified silane polymer joint sealant engineered for precast concrete, expansion joints, and natural stone facades. Combining the weathering resistance of silicones with the high strength of polyurethanes, LP-PU MS500 is 100% paintable, bubble-free, and non-staining, delivering permanent elastic sealing without solvent hazard.
Key Performance Features
Paintable & Bubble-Free Curing
Can be overpainted with most water-based coatings after skin formation. Cures cleanly without outgassing or bubble formation, even on damp concrete substrates.
Non-Staining on Sensitive Substrates
Isocyanate-free, solvent-free, and silicone-oil-free formulation. Prevents fluid migration and edge contamination on natural stone, marble, and granite facades.
±25% Dynamic Movement Accommodation
High elastomeric recovery accommodates structural expansion and contraction caused by thermal cycling and building settling without joint tear.
Primerless Adhesion & Eco-Friendly
Exhibits primerless bond strength to concrete, masonry, aluminum, glass, and metals. Low-odor, low-VOC compliant for sustainable green building standards.
Technical Specifications
| Physical Property | Technical Value | Test Standard |
|---|---|---|
| Base Chemistry | Modified Silane (MS) Polymer | Internal Standard |
| Consistency / Sag | Non-sag (0 mm) | ASTM C639 |
| Movement Capability | ±25% | ASTM C920 (Class 25) |
| Skin Formation Time | 30 – 50 Mins (23°C, 50% RH) | ASTM C679 |
| Curing Rate | 2 – 3 mm / 24 Hours | Internal Standard |
Applications & Substrates
Primary Applications
Precast Concrete (PC Panel) Façade Joints
Architectural Expansion Joints in Commercial Buildings
Natural Stone, Granite & Marble Exterior Cladding
Perimeter Sealing Around Window & Door Frames
Interior & Exterior Masonry / Parapet Joints
Compatible Substrates
Precast Concrete |
Natural Stone & Marble |
Anodized & Powder-Coated Aluminum |
Glass & Glazing |
Brick & Masonry
Application & Surface Prep Guide
Joint Preparation
Joint surfaces must be clean, dry, and free from oil, grease, curing compounds, and loose mortar. Ensure correct joint depth-to-width ratio (1:1 for joints up to 10mm wide; 1:2 for wider joints).
Backer Rod Insertion
Insert closed-cell polyethylene backer rod (PE Backer Rod) into the joint to control sealant depth and prevent three-sided adhesion.
Application & Tooling
Cut nozzle to desired joint width. Extrude LP-PU MS500 evenly into the joint using a manual or pneumatic caulking gun. Tool the surface within 20 minutes using a soapy water solution for a smooth, concave finish.
Curing & Painting
Allow full curing 23℃, 50% RH before exposing to dynamic structural movement. Overcoating can be conducted once skin is fully formed.
Request a Free Sample
The fastest way to find the best solution for your needs is to speak with our team of adhesive experts.
We will quickly narrow down your options and provide you with objective advice on the best fit for your application.