Industrial sealants are mainly used to fill cracks, joints, gaps and other openings. This is to prevent dirt, water, gas and any other foreign substances from seeping in. Serving as a solution to inevitable gaps and cracks, industrial sealants create strong and leak-proof mechanical seals. Industrial sealants are available in a variety of forms, including pastes and liquids that can be applied to diverse surfaces.

Know that the best sealant type for the job isn’t one over the other. It is all about evaluating the performance properties of the sealant as well as determining what type of sealant is best suited for the demands of a project.

Showing 1–12 of 34 results

  • Alsco D-Gel 527 400ml

    Alsco D-Gel 527 400ml – Clear

    £63.45 Excl VAT

    Sold only in Full Box Quantities.
    Two component
    1:1 Mix Ratio
    Low Viscosity
    Sealing and protecting electronic devices

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  • Soudal Butyrub Mastic 300ml

    Butyrub Mastic 300ml

    £2.26 Excl VAT

    Sold only in Full Box Quantities.
    Polybutylene Sealant
    Very Good Adhesion
    UV & Weather Resistant
    Over Paintable
    Excellent resistances to most chemicals

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  • Dowsil 3793 600ml Black

    Dowsil 3793 600ml Black

    £27.16 Excl VAT

    Sold only in Full Box Quantities.
    Outstanding resistance to UV and moisture
    Good adhesion to a range glasses, metals and some plastic spacers
    Fulfils requirement for secondary sealant for insulated glass units used in structural glazing specified by EOTA
    Excellent weathering properties
    Good mechanical properties, high tear strength, elongation and tensile strength

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  • Dowsil 400 Firestop

    Dowsil 400 Firestop

    £4.73 Excl VAT

    Sold only in Full Box Quantities.
    A fire rating of up to 2 hours can be achieved
    Class 2 surface spread of flames classification
    Mean toxicity index 2.0
    Remains flexible
    Resistance to ozone, ultra-violet radiation and temperature extremes

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  • Dowsil 700 Firestop - 380ml

    Dowsil 700 Firestop – 380ml

    £14.02 Excl VAT

    Sold only in Full Box Quantities.
    Meets BS 476 part 22
    Joint movement capability +/-50%
    A fire rating of up to 4 hours can be achieved
    CE marked as a fire resistant according to ETAG 026
    Excellent adhesion to most porous and non porous construction substrates

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  • Dowsil 7091

    Dowsil 7091

    £8.46 Excl VAT

    Sold only in Full Box Quantities.
    One component adhesive/sealant
    Alkoxy cure system
    None sag paste consistency
    Cures to a tough, flexible rubber
    Excellent adhesion to many substrates

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  • Dowsil 732

    Dowsil 732

    £7.30 Excl VAT

    Sold only in Full Box Quantities.
    One component adhesive/sealant
    Acetoxy cure system
    Cures to tough flexible rubber
    Complies with MIL-A-46106
    Complies with FDA 177.2600

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  • Dowsil 781 Cartridge 310ml

    Dowsil 781

    £7.89 Excl VAT

    Sold only in Full Box Quantities.
    High strength
    Good elasticity
    Conforms to ISO 11600-F&G-20LM
    Resistant to ozone, ultra-violet radiation and temperature extremes

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  • Dowsil 784 Glazing Silicone Sealant Cartridge 310ml

    Dowsil 784

    £5.67 Excl VAT

    Sold only in Full Box Quantities.
    Fungus and mildew resistant
    Good Elasticity
    100% Silicone
    Conforms to ISO 11600-G-20LM
    Solvent free

    Dowsil 784 is a single-part silicone sealant with built in ffingicide that resists mould and mildew. It provides a good degree of elasticity and a high gloss appearance. Moreover, it’s compliant with ISO 11600-G-20LM and can withstand extreme temperatures, UV radiation and ozone.

    Dowsil 784 cures quickly (tack free in one hour) and can allow + or -25% joint movement. Note that it’s incompatible with porous materials on external frames.

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  • Dowsil 785+ 310ml

    Dowsil 785+ 310ml

    £6.33 Excl VAT

    Sold only in Full Box Quantities.
    Fungus and mildew resistant
    Gloss Finish
    Bacteriostatic sealant
    Resistant to ozone, ultra-violet radiation and temperature extremes
    Conforms to ISO 11600-F-20LM

    Dowsil 785+ is an acetoxy silicone sealant with a high modulus, adhering well to virtually any non-porous surface. This is a fungicide silicone sealant that resists mould growth. It also inhibits bacterial growth, such as E. coli, Salmonella and MRSA. You can use it to secure sanitary fixtures with a water-resistant hygienic seal. At Alsco, we offer the Dowsil 785+ 310ml in clear and white.

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  • Dowsil 786 Cartridge 310ml

    Dowsil 786

    £9.85 Excl VAT

    Sold only in Full Box Quantities.
    Conforms to BS5889, Type B
    Safe for repeat food contact
    Meets the U.S food and drugs administration regulation no 21CFR177.2600
    High resistant to mildew and mould growth
    Joint movement capability +/- 25%

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  • Dowsil 791

    Dowsil 791

    £5.66 Excl VAT

    Sold only in Full Box Quantities.
    Ideal for expansion, connection, perimeter and other movement joints
    Neutral cure – suitable for use on coated glass, galvanized steel, copper, masonry and more
    Low modulus sealant according to ISO standards, medium modulus according to ASTM standards
    Extension/compression movement capability of up to +/-50% of the original joint width

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FAQs

What is the primary role of sealants?

Typically, an Industrial sealant is designed to seal the spaces between surfaces to prevent the ingress of moisture, to bond surfaces together and provide a damper to vibration and noise. Sealants are applied where either mechanical fixings or more rigid chemical products such as adhesives, resins, mortars or concrete do not offer an effective solution.

As long as they are applied correctly in accordance with the manufacturers guidelines and are not subjected to conditions outside of their cured properties, Adhesives, Resins and Sealants will continue to maintain their characteristics for many years after application.

Which industries use sealants?

Sealants are used in a wide array of industries such as aerospace, automotive, construction, electronics, food, medical, marine and many more. Those working with materials like concrete, ceramics, metal, plastics and textiles also commonly use industrial sealants.

What are the types of sealants?

Various types of industrial sealants are available in the market. The most common are the four below:

Polymer

Products such as MS, STP or hybrid based systems offer the best technical solution for many Industrial applications. These products bond very well to most common surfaces generally without the need for primers and offer good long-term resistance to atmospheric conditions, UV radiation, heat and moisture.

Polyurethane

A forerunner of the newer Polymer technologies, this product type is well established for use in Industrial and construction applications offering good adhesion often with the need for specific primers but is susceptible to degradation and discolouration when subjected to strong UV conditions.

Silicone

A long established highly flexible sealant solution which offers enhanced UV stability and heat resistance characteristics. Generally used for glazing, sanitary, fire rated, food and electronics applications these products are not suitable for overpainting.

Acrylic

This type of sealant is typically used internally as “decorators caulk” or externally where a high movement accommodation is not required. 

How to apply a silicone sealant?

A suitable professional applicator will be required for products that are pre-packed in cartridge format to aid dispensing, see our full range of “dispensers” for selection of the appropriate applicator for the container type/volume.

For all product types it is imperative to ensure all surfaces to be bonded or sealed should be free from dust, debris or surface contaminants by ensuring thorough cleaning prior to application. Guidance can be provided on the most suitable cleaning solution based on the surfaces and bonding/sealing product being used.

Once surfaces have been thoroughly prepared products should be applied to the surfaces as per the manufacturers product guidelines. Adhesives generally will require a thin film applied typically 0.1mm-2.0mm, whereas sealants need a minimum of 5mm depth/width for bonded surfaces to account for dynamic movement and coefficient of expansion with temperature and sufficient width/depth to fill gaps where edge sealing to ensure long lasting water tight seals.

Pre-cut the cartridge nozzle end to the required size to facilitate application to the required width/depth, attach nozzle to the cartridge and insert into a suitable professional applicator for products that are pre-packed in cartridge format to aid dispensing, see our full range of “dispensers” for selection of the appropriate applicator for the container type/volume. Masking tape can be used on joint edges to minimise overspill or excess material to make post application clean-up easier.

It is important to remove excess adhesive or sealant before curing to a solid state, uncured adhesive can be removed using suitable industrial cleaning wipes, uncured sealant can be tooled to a smooth surface and excess removed using a soapy water solution or a moist (free from chlorinated solution) surface wipe.

 

How to apply silicone sealant neatly?

Significant movement of bonded/sealed components or assemblies should be avoided until the adhesive, resin or sealant has cured sufficiently to provide sufficient strength to maintain their structure. Exposed sealants should be left untouched until they have cured to a solid rubber form.

How long does silicone sealant take to dry?

Adhesives can vary in their full cure time based on their particular chemistry type and curing type (single component, dual component, atmospheric cure or heat cure), anything from 5-10 seconds up to 24 hours. Sealants being mainly single component cure which utilise atmospheric moisture and temperature to form a solid rubber (RTV-room temperature vulcanising), they will cure through approximately 3mm every 24 hours of exposure (faster if warmer and more humid, slower where colder and dryer). 

Can you put a new silicone sealant over the old one?

It is not recommend to apply new material over old product, so where there is residual material evident on surfaces, this also needs to be removed mechanically prior to application of new material, remove larger areas by scrapping and then abrasion to remove smaller remaining residues, cleaning can then take place after this process has been completed.

Is silicone sealant waterproof?

The answer to this is yes, silicone sealant is waterproof. Silicone sealants, when applied, can seal out moisture and maintain a stronghold against tough weather conditions. Because of this, silicone sealants are commonly used for bathroom fixtures such as the bathtub, sink, toilet and faucets. They are also great for outdoor applications, which is why they are commonly used for sealing doors and window frames.

What is the difference between Adhesives, Resins and Sealants?

Adhesives are typically used to permanently bond two surfaces together producing a strengthened more rigid assembly. Resins are used to encapsulate assemblies from moisture, temperature or to eliminate reverse engineering. Sealants are used where a more flexible elastomeric joint between two surfaces is necessary.