Enhanced TDS
Identification & Functionality
- Product Type
- Technologies
- Product Families
Features & Benefits
- Ready-to-Use Product Features
- Product Highlights
- FOSTER® MONOLAR® II MASTIC based on chlorosulfonated polyethylene rubber (formerly known as Hypalon®*) is a tough, flexible, fire-resistive, elastomeric finish for protection of thermal insulation.
- It is also used as a vapor retarder finish for fittings.
- It is excellent for outdoor use where good color retention, chemical resistance and durability are required.
- MONOLAR® II MASTIC provides outstanding weather barrier and vapor retarder protection for most board stock thermal insulations except polystyrene.
- It normally bonds well to aluminum foil facings, but a test application is recommended to confirm adhesion.
Applications & Uses
- Limitations
- Store and apply between 40°F and 100°F.
- For best results, select Elastolar® 95-44 or Flextra® 95- 50 for insulation joint sealing under Monolar® II Mastic.
- Always test plastic materials for compatibility when using a solvent-based product.
- Outdoor horizontal surfaces must always drain completely.
- A pitch of at least 1/2 inch per foot (4 cm/m) is required.
- Make certain this product is completely dry and the area free from solvent odor if food is involved.
- Select Monolar® Coating 60-95 (white) or 60-96 (gray) for airless spray or brush application.
- Preparation and Application Information
Material Preparation
- Stir well.
- Do Not Think.
- Apply only to clean, dry surfaces.
- Keep container closed when not in use to prevent solvent evaporation.
Application
- To prevent water vapor and moisture infiltration, proper and complete flashing is required.
- Follow flashing specifications.
- Normal Service: Apply a tack coat of MONOLAR® II Mastic at a thickness of 1/32 inch (0.8 mm). This is equivalent to 2 gal./100 sq. ft. (0.8 l/m2). Embed Foster® MAST-A-FAB® or CHIL-GLAS® #10 White Membrane into wet tack coat. Smooth membrane to avoid wrinkles and overlap all seams at least 2 inches (5 cm). Apply a finish coat of MONOLAR® II Mastic at a minimum thickness of 1/16 inch (1.6 mm). This is equivalent to 4 gal./100 sq. ft. (1.6 l/m2). This finish coat shall be applied no later than 2 hours after the tack coat and shall completely cover membrane. This application shall provide a minimum dry film thickness of 30 mils (0.7 mm).
- Severe and Cryogenic Service: After the first two coats have dried, apply an additional coat of MONOLAR® II Mastic at a thickness of 3/64 inch (1.2 mm). This is equivalent to 3 gal./100 sq. ft. (1.2 l/m2). This additional application shall provide a minimum dry film thickness of 44 mils (1.1 mm). On rough or porous insulation surfaces additional product will be required to achieve the full surface dry film thickness. The application rate may need to be increased by up to 20% or more to achieve minimum film thicknesses.
- Trowel: Use clean tools. Work in long, even strokes to ensure uniform thickness. Wet tools with detergent foam (not soap) occasionally to prevent a buildup of dried mastic.
- Rubber Glove: Best appearance may be achieved by smoothing wet MONOLAR® II Mastic with detergent foam (not soap) on clean glove or brush, being careful not to pick up any MONOLAR® II Mastic onto the glove or brush.
Clean Up
- Use xylol (flammable) or chlorinated solvent (non-flammable) for cleaning equipment. Dried MONOLAR® II Mastic is extremely difficult to remove.
Properties
- Typical Properties
- Application Properties
- Flame Characteristics
- Note
¹ - Monolar® II Mastic meets the permeance requirements of ASTM C755-19 for below ambient vapor retarder coatings.
² - Tested at coverage rate of 25 sq. ft./gal. Applied to 1/4 inch (6.4 mm) inorganic reinforced cement board. The flame spread may vary at different product thicknesses and/or when applied over other surfaces.
| Value | Units | Test Method / Conditions | |
| Average Weight / U.S. Gallon | 8.8 - 9.3 | lbs. | ASTM D1475 |
| Average Non-Volatile (by Volume) | 30.0 | % | ASTM D2369 |
| Average Non-Volatile (by Weight) | 43.0 | % | ASTM D2369 |
| Water Vapor Permeance (at 54 mils dry)¹ | 0.02 | perms | ASTM E96, Procedure A |
| Drying Time (Set to Touch) | 3.0 | Hours | - |
| Drying Time (Dry Through) | 48.0 | Hours | - |
| Flash Point | 104 | °F | ASTM D3278 |
| Value | Units | Test Method / Conditions | |
| Service Temperature Limits (at coated surface) | -40 to 250 | °F |
| Value | Units | Test Method / Conditions | |
| Flame Spread ² | 20 | ASTM E84 | |
| Smoke Developed ² | 10 - 40 | ASTM E84 |
Regulatory & Compliance
- Certifications & Compliance
Storage & Handling
- Shelf Life
- 6 months