MS991 Modified Silicone Sealant
MS991 Modified Silicone Sealant is a low modulus, one component, neutral room temperature curing, formaldehyde-free and isocyanate-free, environmentally friendly construction sealant. It has excellent bonding properties for most building materials such as precast concrete units, fiber cement boards, stone, ceramics, aluminum, and aluminum-plastic panels, etc. It can be widely used in joint sealing of pre-casting concrete construction and joint sealing of general buildings, with excellent weather resistance and waterproof performance.
FEATURES & BENEFITS:
• Healthy and environmentally friendly, free of formaldehyde and isocyanate, solvent-free, non-toxic and tasteless, ultra-low VOC
• Easy to use, can be applied with a conventional caulking gun, one part and no mixing required
• Surface paintability, compatible with most architectural coatings
• Non-pollution, no pollution to porous substrates such as stone and concrete, Overcome the shortcomings of ordinary silicone sealant which easily contaminate the substrate
• No slumping; can be used for the sealing of vertical and wide joints
• Good movement capability, can accommodate ±25% movement in a properly designed joint
• Excellent weather and aging resistance, long-term superior tensile, compression and shear stress relaxation, ensuring seal durability and excellent water resistance
APPLICATIONS:
• Joint seals of prefabricated building exterior wall
• Joint seals of prefabricated building balconies
• Waterproof and leak-proof seal for building roofs
• Sealing and bonding of flashing, gutter, wall cladding
• Caulking and Sealing of interior joints
• Many other industrial and architectural uses
TECHNICAL SPECIFICATIONS AND STANDARDS:
This sealant meets or exceeds the requirements of:
• JC/T 881-I-N-25LM
• ASTM C920 Grade NS, Class 25
QUALITY ASSURANCE:
This product has passed ISO9001/ISO14001 management system certification, and strictly in accordance with ISO9001 quality system requirements for production and control of product quality.
COLOUR:
• Black, grey, white or other colors required by the user
PACKAGING INFORMATION:
MS991 Modified Silicone Sealant is supplied in 300 ml disposable plastic cartridges, 590 ml foil sausages and 200L drum bulk packaging.
USABLE LIFE AND STORAGE:
When stored at or below 27°C in the original unopened containers, it has a usable life of 12 months from the date of production.
JOINT DESIGN:
The correct Joint design reduces stress on the sealant, provides optimum sealant movement, facilitates sealant application, and reduce the cohesive failure of the sealant and reduce the risk of cracking.
• The width and depth of the joint should be no less than 6 mm respectively
• For larger joint, the width of the joint should be greater than the depth of the sealant
• Avoid three-sided bonding and use a backing rod or tape on the bottom of the joint
HOW TO USE:
• Surface Cleaning
The surface of the substrate should be sufficiently clean and dry, completely remove any residual impurities and the original sealant. For non-permeable surfaces, such as glass and sprayed aluminum alloys, use a clean, white, lint-free cotton cloth dipped in a non-oily solvent such as methyl ethyl ketone, propanol or 75% alcohol to remove greasy and contaminants; Wipe off any residual solvent and contaminants with another dry cloth.
• Backing Materials
If backing material is required, use a closed cell type polyethylene or open cell type polyethylene foam, or similar material at the bottom of joints to control the depth of sealant. For shallow joints, use low-viscosity polyethylene tape as the backing material. Avoid three-sided bonding by preventing the sealant from sticking to the bottom of the joint.
• Masking Tape
The area near the joint needs to be covered. By using masking tape, the working line of the seal can be perfectly neat, and the appearance of the periphery of the joint is clean and the surrounding sealant can be prevented from contaminating the surface of the substrate. Never use tape onto the surface where the sealant will be applied.
• Primer:
When using MS991 Modified Silicone Sealant, whether need to use the primer solution based on the results of the material adhesion test report. For the sealing of prefabricated building concrete units, in order to achieve a longer bonding effect, the surface of the substrate should be treated with a matching primer.
• Applying sealant
Use a pneumatic glue gun or a manual caulking gun to apply the sealant to the bottom of the joint so that the joint is completely filled and the substrate on both sides of the joint is fully contacted. Do not apply the sealant to the surface simply because the sealant will not fill the joint under its own weight.
Do not touch the surface of the sealant within 48 hours after surface curing. In the process of sealant curing, should avoid contact with detergent or solvent.
• Surface Paintable
MS991 Modified Silicone Sealant could be painted over after curing or dried with coating materials like epoxy or acrylic paints. With the matched accelerator, it can better solve the problem of decorative treatment such as decorative mortar and natural texture stone paint on the surface of the sealant.
Please test the coating if it involves solvent contents like enamel or oil base paints. Coating should have similar tensile strength compared with adhesive in order to get best appearance and property.
Painting could be processed after 24 hours if thickness of adhesive is less than 3 mm and 48 hours if thickness more than 3 mm.
PRECAUTIONS:
• When bonding cement and concrete substrates, the substrate must be completely dried and cured for 7 days before applying sealant, otherwise it will affect the bonding performance
• Temperature and humidity will affect the curing performance of the sealant. When the surface temperature of the substrate is lower than 4 °C or higher than 40 °C, it is not suitable for applying sealant
• Keep the product out of reach of children
• Avoid contact with eyes and skin before sealant curing. If contact with the skin, first scrub with soapy water or alcohol, then rinse with water; if contact with eyes, first rinse with plenty of clean water, if necessary, seek medical attention immediately
• Before using, please read the safety data sheet of the product to obtain the safety data of the product
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