Megapoxy P1

For high-strength structural bonding and concrete repair, Megapoxy P1 is a two-component gap-filling epoxy paste formulated for vertical, overhead, and damp-condition applications. It is chemically resistant to hydrogen sulphide in sewage systems and complies with AS/NZS 4020:2018 for contact with potable drinking water, making it suitable for repairing concrete tanks, pipes, and marine or municipal infrastructure.

What it does

Megapoxy P1 combines a DGEBA epoxy resin with a carbonate-free filler to create a dark grey structural paste that does not sag on vertical or overhead surfaces. It provides permanent bonding and structural patching across dissimilar materials, including concrete, metals, natural stone, brick, and fibre cement sheet. When applied directly to grit-blasted steel at a minimum thickness of 3mm, the cured epoxy layer provides corrosion protection equivalent to approximately 50mm of concrete cover.

Numbers that matter

• 80 MPa ultimate compressive strength (ASTM C579): Provides structural load-bearing capacity superior to standard concrete, preventing crush failures under heavy loads.
• >3 MPa concrete bond strength (ASTM D4541): Exceeds the tensile strength of concrete, ensuring the concrete substrate will fail structurally before the epoxy bond line separates.
• 18 MPa steel tensile bond strength (ASTM D897): Delivers high-adhesion mechanical anchors when bonding metal plates, bracketry, or grouting bolts.
• 60-minute work time (at 25°C): Generates a practical installation window to blend, apply, and align heavy precast panels, stones, or steel components before curing begins.
• 1:1 mixing ratio by volume: Equal parts white Part A and black Part B simplify onsite mixing and reduce batching errors.

Where to use it

Megapoxy P1 is suitable for the following structural bonding and repair jobs:

• Bonding precast concrete articles, bricks, ceramics, and compressed cement sheet.
• Bonding metal components to other metals or to concrete substrates.
• Grouting starter bars, threaded rods, and structural bolts.
• Securing and aligning natural stone panels.
• Filling and repairing concrete pipes, tanks, columns, stairs, and insitu formed concrete.
• Flush-filling countersunk screw holes in fibre cement sheet and repairing damaged fibreglass articles.

How to apply

Concrete preparation: Clean the surface of all grease and oil. Remove surface laitance using mechanical scabbling, grit blasting, or diamond grinding. If mechanical preparation is not possible, acid etch with a 1:1 mixture of concentrated hydrochloric acid and water at a rate of 0.5 litres per square metre. Allow to react for 10 minutes, wash thoroughly, scrub with a stiff broom, and allow to dry for 24 hours. The substrate should be surface dry for maximum adhesion.

Metal preparation: Grit blast steel and other metals to AS 1627.2.2002. If grit blasting is not possible, mechanically abrade to a clean, bright finish, then flood-degrease with an industrial-grade solvent. Wire brushing is not satisfactory and results in minimal adhesion.

Coated surfaces: Remove all paints, coatings, and galvanising before bonding. For coated concrete, remove paint via flame-cleaning or with a scutching tool, then complete with diamond grinding or scabbling. For coated metals, apply a high-quality paint stripper, then grit blast or grind to a bright metal finish.

Mixing: Thoroughly blend Part A and Part B together at the 1:1 volume ratio. Incorrect ratios or incomplete mixing will lower the physical properties of the cured system, prevent a satisfactory cure, or cause discolouration over time.

Limitations

• Do not apply Megapoxy P1 at temperatures below the minimum application threshold of 10°C.
• Do not rely on wire brushing for metal preparation, as it results in minimal bond adhesion.
• Do not apply directly to coated, painted, or galvanised surfaces; failure to remove coatings before bonding will result in inferior bond strength.