Nitobond EP - Epoxy Resin Bonding Agent: Technical Details, Specifications, and Features

Product Overview

Nitobond EP is a high-strength epoxy bonding agent and primer manufactured by Fosroc International Limited. It is specifically engineered as a two-component solvent-free material designed for bonding fresh cementitious materials to existing cementitious surfaces and serves as a substrate primer for very porous concrete substrates.

Product Composition

Nitobond EP is based on solvent-free epoxy resins containing pigments and fine fillers. The formulation provides:

• Base component: White in color
• Hardener component: Black in color
• Mixed result: Uniform grey color, providing visual evidence of adequate mixing

This two-component system is supplied in pre-weighed quantities ready for on-site mixing and use.

Available Pack Sizes

Nitobond EP is available in two container sizes to accommodate various project scales:

• 1.5 litre pack containing:

  • Base component (FC321025-1L)
  • Hardener component (FC321026-500ML)

• 6.0 litre pack containing:

  • Base component (FC321025-4L)
  • Hardener component (FC321026-2L)

Coverage Rate

Nitobond EP provides approximate coverage of 4-5 square meters per litre. Coverage figures are theoretical; practical coverage figures will be reduced due to wastage factors and substrate variability.

Key Performance Specifications

Nitobond EP demonstrates exceptional mechanical properties:

Property	Value
Compressive Strength	50 MPa
Tensile Strength	20 MPa
Flexural Strength	35 MPa
Shear Strength	25 MPa
Adhesive Bond to Concrete	Generally exceeds the tensile strength of the host concrete
VOC Content	19 g/litre

Curing and Application Timeline

Parameter	Specification
Pot Life	35 - 45 minutes at 20°C
Initial Hardness	24 hours at 20°C
Full Cure	7 days at 20°C
Maximum Overlay Time	90 minutes at 20°C
Minimum Application Temperature	5°C

The overlay time of 90 minutes indicates that fresh concrete or mortar should be applied to the coated substrate while Nitobond EP remains tacky, typically between application and 90 minutes at 20°C.

Applications

Nitobond EP is ideal for use in:

• Roads and bridges - bonding new concrete to existing structures
• Pavements - for surface overlay applications
• Loading bays - repair and bonding work
• Industrial facilities and factories - concrete strengthening and repair
• Bonded or granolithic floor toppings - as adhesive layer
• Repair systems where a substrate/repair barrier is required
• Permanently wet or damp substrate conditions - as an alternative bonding aid
• Horizontal or vertical surfaces supported by formwork

Standards Compliance

Nitobond EP complies with:

• AS 4020-2018 standard
• AWQC Report 323179

Application Methods

Nitobond EP can be applied using multiple techniques:

• Brush application - applied with suitable brush to prepared surfaces
• Spray application - requires heavy-duty airless spray equipment such as Graco airless spray fitted with 19-20 thou tip

Surface Preparation Requirements

Before Nitobond EP application, surfaces must be:

• Cleaned to remove dust, unsound material, plaster, oil, paint, grease, corrosion deposits, and algae
• Roughened and laitance removed through light scabbling or grit-blasting
• Assessed for soundness using pull-off testing after decontamination
• Oil and grease deposits removed by steam cleaning, detergent scrubbing, or proprietary degreasers

Mixing Instructions

Proper mixing is critical for optimal performance:

1. Stir hardener and base components separately to disperse any settlement
2. Pour entire contents of hardener tin into base tin
3. Mix thoroughly using a suitable slow-speed heavy-duty drill and mixing paddle
4. Mix for 2 minutes until fully uniform grey color is obtained
5. Scrape sides of container
6. Continue mixing for a further 2 minutes

Temperature Working Conditions

Low Temperature Working (Below 15°C)

• Separate components should be warmed to maximum 25°C before mixing
• If heated to 25°C, pot-life reduces to 20 minutes
• Alternatively, store material in 20°C environment and use immediately before application
• Cure rate will be slower below 20°C

High Temperature Working (Above 30°C)

• Material should be stored in shade or air-conditioned environment for 12 hours before use
• Cure rate will be faster above 20°C

Cleaning and Maintenance

Nitobond EP should be removed from tools, equipment, and mixers immediately after use using:

• Fosroc Solvent 10, or
• Water (for initial cleaning)

Hardened material can only be removed mechanically.

Storage and Shelf Life

• Shelf life: 24 months from manufacture date
• Storage conditions: Dry store in original unopened packs
• Note: Shelf life may be reduced if stored at high temperatures

Advantages

• High strength adhesion - exceeds the tensile strength of host concrete
• High mechanical strength - suitable for demanding applications
• Substrate flexibility - can be applied to dry or SSD (surface saturated dry) damp substrates
• Solvent-free formulation - can be used in enclosed locations
• Long working time - 90-minute overlay time suitable for complex applications requiring formwork or steel reinforcement fitting
• Dual functionality - serves as both bonding agent and substrate primer

Limitations and Precautions

• Should not be applied when temperature is below 5°C or is 5°C and falling
• In cold conditions (<15°C), Nitobond EP may not set quickly enough to bond to rapidly setting toppings, potentially causing delamination
• If Nitobond EP becomes tack-free before overlay application, a second coat is required
• Any second coat must be applied the same day as the first coat; otherwise, the first coat requires mechanical removal

Related Products

Nitobond EP works in conjunction with:

• Nitomortar EL-HB - applied to primer-coated substrate within 90 minutes while primer is tacky
• Nitomortar 908 - two-component epoxy repair mortar
• Nitomortar AP - for filling voids and imperfections
• Renderoc - repair material applied to tacky Nitobond EP surface

Safety and Documentation

• Safety Data Sheet (SDS) - Available from Fosroc website
• Technical Data Sheet (TDS) - Should be read carefully prior to use
• Emergency contact: Poisons Information Centre (13 11 26 within Australia)

References

• [1] Fosroc_Nitocote_EP410_TDS.pdf
• [2] Fosroc_Nitobond_EP_TDS.pdf
• [4] Fosroc_Nitomortar_908_TDS.pdf