

-
Description for Bostik Chem-Calk 2020
A one-component, moisture curable advanced urethane sealant that offers superior adhesion to vinyl siding, vinyl trim board, and a variety of dissimilar surfaces. It is suitable for most building materials including stone, masonry, wood, aluminum and a variety of other metals.Application Type Bond, Seal 1 Part or 2 Part 1-Part Material Form Paste Substrate Aluminum, Ceramic, Metals, Steel, Stone, Wood, A variety of dissimilar surfaces, Vinyl siding, Vinyl trim board Manufacturer Bostik Chemistry Solvent-free, advanced urethane Cure Method Moisture Color Blue Gray, Beige, Gray, Cream, Clay, Maple, White, Bronze, Tan, Stone, Heather, Antique White, Pearl High Temperature Resistance (°C) 82 Low Temperature Resistance (°C) -40 Key Specifications ASTM (American Standard Test Method): C920: ASTM C920, TYPE S, GRADE NS, CLASS 50, USE NT, A AND M., CAN/CGSB (Canadian General Standards Board): Canadian Specification SAC/CGSB 19.13-M87 -
Technical Data for Bostik Chem-Calk 2020
Overview
-
1 Part or 2 Part
- 1-Part
-
Material Form
- Paste
-
Industry
- Construction - Masonry
- Other - vinyl siding, vinyl trim board and other engineered woods, vertical applications, Multi-environmental use
-
Chemistry
- Solvent-Free
- Polyurethane - advanced urethane
-
Cure Method
- Moisture / Condensation Cure - Moisture
-
Color
- Blue - Blue Gray
- Brown - Beige, Tan
- Gray - Stone
- Off-White - Cream
- Red - Maple
- White - Antique White, Pearl
- Yellow - Bronze
- Other - Clay, Heather
-
Key Specifications
- ASTM (American Standard Test Method) : C920 : Class 50 - ASTM C920, TYPE S, GRADE NS, CLASS 50, USE NT, A AND M.
- CAN/CGSB (Canadian General Standards Board) : 19.13 - Canadian Specification SAC/CGSB 19.13-M87
Specifications
Cure Specs
Tack Free Time (min) 60 Test Method Bond Strength
Tensile Strength (psi) 220 Test Method Material Resistance
High Temperature Resistance (°C) 82 Low Temperature Resistance (°C) -40 Hardness
Shore A Hardness 40 Test Method Elongation (%) 700 Test Method Other Properties
Flash Point (°F) 143.6 Test Method Business Information
Shelf Life Details Shelf life of Chem-Calk 2020 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. Not Good For
Don't Use For Do not apply over damp, contaminated, loose surfaces (See Installation Protocol and Surface Preparation), old sealants or other foreign substances that may impair the adhesion bond. Avoid air entrapment, Porous substrates, must not be used to seal narrow joints, fillet joints and face nail holes., Smearing and feathering, horizontal joints or traffic-bearing joints where abrasion resistance is required, continuous immersion_x00D_ in water or any other fluid, exterior or interior sealing below the waterline, do not expose to curing silicone sealants, curing Bostik Chem-Calk 2000, alcohol, acids or solvent-based materials., glazing applications. Bond line strength can be affected by UV rays through the clear material (glass, acrylic glass, polycarbonate, etc.). -
Best Practices for Bostik Chem-Calk 2020
-
Design
In general, more joint movement can be accommodated in a thin bead of sealant than a thick bead. Chem-Calk 2020 Advanced Polyurethane Sealant should be no thicker than 1/2” (12.7mm) and no thinner than 1/4” (6.4mm). In joints between 1/2” and 1”, the ratio of sealant width to depth should be approximately 2:1. Sealant depth in joints between 1/4” and 1/2” should be 1/4” deep. Joints with dynamic movement should not be designed in widths less than 1/4”.
-
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.
To remove laitance and any other loose material, clean concrete, stone or other masonry materials with non-alcoholic 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.
-
Application
Chem-Calk 2020 comes ready-to-use. Cut spout or tip to desired bead size. Apply moderate pressure to break seal inside the nozzle. Apply by using a professional caulking gun such as Bostik® K410042TG. Use opened cartridges and sausages the same day they are opened. Apply Chem-Calk 2020 Polyurethane Sealant in a continuous operation using positive pressure to the bottom of the joint to properly fill and seal the joint. When applying, avoid air entrapment and overlapping. Tool the sealant before the skin forms with adequate pressure to spread the sealant against the backup material at the bottom and sides of the joint. A dry tool with a concave profile is recommended for that operation. Do not use water or soapy water for this operation. Avoid smearing and feathering of the sealant to allow full performance of the cured seam. Excess sealant should be dry-wiped or joints should be properly taped.
If the sealant becomes damaged, replace the damaged portion by removing the old sealant completely, cleaning the surfaces and reapplying a fresh and appropriate amount of new sealant in accordance with the directions and information contained in this data sheet.
-
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).
-
Testing
In general, application of Chem-Calk 2020 does not require priming the substrates. However, some substrates may require a Bostik primer. It is the user’s responsibility to check adhesion of the cured sealant on typical test joints at the project site before and also during application as weather conditions may affect the adhesion results.
A hand pull test must be run before the job starts and at regular intervals during the job. It must be run on the job site after the sealant is fully cured, usually within 7 to 21 days. (Adhesion may develop fully after at least 14 days.)
The hand pull test procedure is as follows: Make a knife cut horizontally from one side of the joint to the other.
Make two vertical cuts approximately two inches long, at the sides of the joint, meeting the horizontal cut at the top of the two-inch cuts.
Grasp the two-inch piece of sealant firmly between the fingers and pull down at a 90° angle or more, and try to pull the uncut sealant out of the joint.
If adhesion is sufficient, the sealant should tear cohesively in itself.
Sealant may be replaced by applying more sealant in the same manner as it was originally applied. Care should be taken to ensure that the new sealant is in contact with the original, and that the original sealant surfaces are clean, so that a proper bond between the new and old sealant will be obtained.
-
-
Comparable Materials for Bostik Chem-Calk 2020
Spec Engine® Results
Closest Results from this Manufacturer
Popular Articles
Testing the effectiveness of surface treatments
Read ArticleAnaerobic Adhesives
Read ArticleInfographic: ENSURING A STRONG BOND - 6 Basic Methods of Surface Preparation
Read ArticleWhat Are the Differences Between Adhesives and Sealants?
Read ArticleSponsored Articles
Unique Advantages of Contact Adhesives
Read ArticleUsing LOCTITE® 454™ is a Valid Option for Engineers Working with a Wide Variety of Materials
Read ArticleSylgard 184 by DOW is the Top Choice for a Transparent, Silicone Encapsulant. Read Why:
Read ArticleCase Study: Creating reliable, corrosion-free bonds with LORD® 406 acrylic adhesive
Read ArticleFeatured Ads

Tack Free Time Test Methods
Tack Free Time | Test Method |
---|---|
60 min | Bostik Test Method |
Tensile Strength Test Methods
Tensile Strength | Cure Time | Cure Temperature | Cure Humidity | Test Method |
---|---|---|---|---|
220 psi | 20,160 min | 25°C | 50 % | ASTM D412, After 14 days cure at 77°F and 50% RH |
Elongation Test Methods
Elongation | Test Method |
---|---|
700 % | ASTM D-412 (After 7 days cure at 77ºF and 50% RH) |
Shore A Hardness Test Methods
Shore A Hardness | Shore Hardness Test Method |
---|---|
40 | ASTM D2240 (After 14 days cure at 77°F and 50% RH) |
Flash Point Test Methods
Flash Point | Test Method |
---|---|
62.0°C | ASTM D3828 |