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Description for Bostik Chem-Calk 950
One-component, construction grade pourable sealant capable of dynamic joint movement; properties remain stable in severe weather and temperature changes.Note: This material has been discontinued. Please view the Comparable Materials tab or call us at (262) 293-7970 for additional help.
Application Type Bond, Seal 1 Part or 2 Part 1-Part Material Form Paste Substrate Ceramics, Porous, Steel, Masonary, Wood Manufacturer Bostik Chemistry Polyurethane Cure Method Moisture Cure Temperature (°C) 25 Cure Time (min) 8,640 Viscosity (cPs) Non-Sag, Pourable Color Limestone, Limestone, Stone Ozone Resistance Excellent Ozone resistance High Temperature Resistance (°C) 66 Low Temperature Resistance (°C) -29 Durability Tough -
Technical Data for Bostik Chem-Calk 950
Overview
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1 Part or 2 Part
- 1-Part
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Material Form
- Paste
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Industry
- Industrial - Control and perimeter joints, Malls, Sealing expansion joints
- Construction - Driveways, Factory floors, Institutional floors, Parking decks, Patios, Pavements, Plazas
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Chemistry
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Application Method
- Caulking gun
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Cure Method
- Moisture / Condensation Cure - Moisture
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Color
- Gray - Limestone, Stone
- Off-White - Limestone
Specifications
Cure Specs
Cure Temperature (°C) 25 Cure Time (min) 8,640 Viscosity (cPs) Non-Sag, Pourable Tack Free Time (min) 240 Test Method Work / Pot Time (min) 110 Bond Strength
Peel Strength (piw) >30 Test Method Tensile Strength (psi) 171 Test Method Material Resistance
Ozone Resistance Excellent Ozone resistance UV Resistance Good Test Method High Temperature Resistance (°C) 66 Low Temperature Resistance (°C) -29 Hardness
Durability Tough Shore A Hardness 48 Test Method Elongation (%) 5 Test Method Flexibility Flexible Modulus (psi) 140 Test Method Business Information
Shelf Life Details Shelf life of Bostik® Chem-Calk® 900 must be checked prior to using the product, do not use past its shelf life. Caulk past its shelf life may not perform or adhere as described by this data sheet. High temperature and high relative humidity may reduce significantly the shelf life of polyurethane sealants. If you are unsure of the expiration date of your Bostik product, please call customer service at 1-888-603-8556 to check if the product is still within its shelf life. -
Best Practices for Bostik Chem-Calk 950
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Surface Preparation
See limitations about surface preparation. Surfaces must be structurally clean, dry (no frost) and structurally sound, free of contaminants, including but not limited to dust, dirt, loose particles, tar, asphalt, rust, mill oil, etc. If substrate is painted or coated, scrape away all loose and weakly bonded paint or coating. Any paint or coating that cannot be removed must be tested to verify adhesion of the sealant or to determine the appropriate surface preparation if needed. (See ASP section on next page for details.) To remove laitance and any other loose material, clean concrete, stone or other masonry materials with nonalcoholic-based solvent by washing, grinding, sandblasting or wire brushing as necessary . Do not use water to clean substrates. Dust must be thoroughly removed after cleaning.
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Curing
Bostik® Chem-Calk® 950 is a moisture cure, polyurethane sealant. On wood, with ambient air at 50% relative humidity and at 73°F, polyurethane sealants will generally skin within twenty-four hour and cure 1/16 of an inch per day. Lower temperature and lower relative humidity will significantly increase the skin time and cure time of a polyurethane sealant.
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Clean-Up
After dry-wiping uncured sealant from substrates and tools, remaining uncured sealant can be removed by using Xylene, Toluene or similar aromatic solvents. Please refer to the MSDSs provided for these solvents before use. Bostik® Hand and Tool towels can also remove uncured sealant. Cured sealant is usually very difficult to remove without altering or damaging the surface to which the sealant has been misapplied. Cured sealant can be removed by abrasion or other mechanical means (scrapers, putty knives).
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Comparable Materials for Bostik Chem-Calk 950
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Tack Free Time Test Methods
Tack Free Time | Test Method |
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240 min | C679 |
Tensile Strength Test Methods
Tensile Strength | Cure Time | Cure Temperature | Cure Humidity | Test Method |
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171 psi | >10,080 min | 25°C | 50 % | @ Break, ASTM D 412, After 7 days cure at 77°F and 50% RH |
Peel Strength Test Methods
Peel Strength | Cure Time | Cure Temperature | Cure Humidity | Test Method |
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>30 piw | >10,080 min | 25°C | 50 % | TT-S-00230C/ASTM C 794, After 7 days cure at 77°F and 50% RH |
UV Resistance Test Methods
UV Resistance | Test Method |
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Good | ASTM C 793 |
Elongation Test Methods
Elongation | Test Method |
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5 % | ASTM D 412, at Break |
Modulus Test Methods
Modulus | Test Method |
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140 psi | @ 100% Elongation ASTM D 412, After 7 days cure at 77°F and 50% RH |
Shore A Hardness Test Methods
Shore A Hardness | Shore Hardness Test Method | Hardness Temperature |
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48 | ASTM D 2240, After 7 days cure at 77°F and 50% RH | 25°C |