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    ​​​​​​MasterSeal 901 - Vinyl Ester Methacrylate resin for crack injection via injection hoses and packers


    What is MasterSeal 901? 

    ​​MasterSeal 901 is a multi-component, solvent-free, water swelling vinyl ester-based injection system that cures to form a flexible yet solid material with an excellent bond even to wet substrates. Depending on the degree of availability of moisture, the cured system swells reversibly up to 120% of its volume to act as an effective and permanent seal against ingress of water

    How does MasterSeal 901 work?

    MasterSeal 901 is based on vinyl ester methacrylate technology. Injection into MasterSeal 900 hose system or directly into concrete and rock. Due to its low viscosity microcracks and capillaries can easily be filled by injection.

    Where​ is MasterSeal 901 recommended for use​​? 

    MasterSeal 901 is recommended for sealing cracks, joints and crevices in concrete, rock and masonry to prevent water ingress. Applications include the injection of: 

    • Cracks, fissures and seams in the rocky strata of mines and tunnels.
    • Stabilized cracks and non-moving joints in structural concrete. 
    • Concrete construction joints using MasterSeal 909.​​

    What are the features​​ and benefits of MasterSeal 901?

    • Swells in contact with water, increasing its volume, preventing water ingress even when the crack moves. No other materials have the same characteristics. 
    • Good bond to damp surfaces - an advantage in damp structures. 
    • When in contact with water, no extraneous reactions take place, therefore no gas bubbles or foam layer are formed, both of which would hinder the bonding process.
    • Able to withstand continuous and high water pressures. 
    • In wet and humid conditions, there is a balance between the water content of the adjacent medium and MasterSeal 901.
    • Remains expanded when concrete has a moisture content.
    • The expansion of MasterSeal 901 is reversible and is unaffected by ageing or electrolytic water.
    • Works in a saline environment. 
    • Suitable for injection with one component or two-component pumps.

    Download the MasterSeal 901 Technical Data Sheet

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    MasterSeal 901 Technical Data Sheet

    pdf (386.70 Kb)


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