Sikaflex® NP 125

• ASTM C 920, Type S, Grade NS, Class 12.5, Use T, NT, M, A and O
• Federal Specification TT-S-00230C, Type II, Class B

Sikaflex® NP 125 is a one-component thermoplastic rubber.

Plastic Cartridges: 18 months when properly stored
Composite Cartridges: 2 years when properly stored

Store in original, unopened containers away from heat and direct sunlight. Storing at elevated temperatures will reduce the shelf life.

Elongation Strength

-40 to 180 ° F (-40 to 82° C)

Weight loss, after heat aging

Cracking and chalking, after heat aging

Rheological, (Sag in vertical displacement)

The cure of Sikaflex® NP 125 varies with temperature and humidity. The following times assume 75° F (24° C), 50% relative humidity, and a joint ½” width by ¼” depth (13 by 6 mm).

• Skins: 10–15 minutes
• Full cure: approximately 2 weeks

A 1⁄2" round bead will yield approximately 7.7 linear feet (2.35 m) per cartridge

• Protect unopened containers from heat and direct sunshine.
• In cool or cold weather, store the container at room temperature for at least 24 hours before use.
• Do not apply over freshly treated wood; treated wood must have been weathered for at least 6 months.
• Not for use in glazing applications. Do not apply on glass and plastic glazing panels.
• Sikaflex® NP 125 can be applied below freezing temperatures only if substrates are completely dry, free of moisture, and clean. Contact Technical Service for more information.
• Lower temperatures and humidities will extend curing times.
• Pursuant to accepted industry standards and practices, using rigid paints and/or coatings over flexible sealants can result in a loss of adhesion of the applied paint and/or coating, due to the potential movement of the sealant. However, should painting and/or coating be desired, it is required that the applicator of the paint and/or coating conduct on-site testing to determine compatibility and adhesion.
• Proper application is the responsibility of the user. Field visits by Sika personnel are for the purpose of making technical recommendations only and not for supervising or providing quality control on the jobsite.

Substrates must be structurally sound, fully cured, dry, and clean. Substrates should always be free of the following: dirt, loose particles, oil, grease, asphalt, tar, paint, wax, rust, waterproofing or curing and parting compounds, membrane materials, and sealant residue.

  
Concrete, Stone, And Other Masonry
Clean by grinding, sandblasting, or wire brushing to expose a sound surface free of contamination and laitance.

  
Wood
New and weathered wood must be clean, dry, and sound. Scrape away loose paint to bare wood. Any coatings on wood must be tested to verify the adhesion of the sealant or to determine an appropriate primer.

  
Metal
Remove scale, rust, and loose coatings from metal to expose a bright white surface. Any coatings on metal must be tested to verify the adhesion of the sealant or to determine an appropriate primer.

Joint Preparation

1. The product may be used in sealant joints designed in accordance with SWR Institute’s Sealants—The Professional’s Guide.
2. In optimum conditions, the depth of the sealant should be ½ the width of the joint. The sealant joint depth (measured at the center) should always fall between the maximum depth of ½" and the minimum depth of ¼".
3. When using as a roof tile adhesive, make sure surfaces are clean and dry.

General Applications

1. Sikaflex® NP 125 comes ready to use. Apply using a professional-grade caulking gun. Do not open cartridges or cans until preparatory work has been completed.
2. Apply a bead of Sikaflex® NP 125 sufficient enough in size to make a bond between the two substrates. 

Roofing Applications

1. For roofing applications, ensure a sufficient amount of Sikaflex® NP 125 is applied to make a bond between the two tiles on the upper surface of the downslope tile. Then install the upslope tile and press into the bead of Sikaflex® NP 125 to ensure good contact between the adhesive and both tiles.
2. Install the upslope tile and press into the bead of Sikaflex® NP 125 to ensure good contact between the adhesive and both tiles.

1. Immediately after use, clean equipment with SikaSwell®-990 or xylene. Use proper precautions when handling solvents.
2. Remove cured sealant by cutting with a sharp-edged tool.
3. Remove thin films by abrading.