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Epoxypro EPH-300 Slow Cure Hardener 3:1
EpoxyPro EPH-300
Deep-Cure 3:1 Hardener, Low Exotherm, Structural & Deep Casting Grade
EpoxyPro EPH-300 is a slow reacting 3:1 epoxy hardener engineered for deep sections, large casting volumes, transom rebuilds, structural grouting and heavy-duty industrial repairs.
When combined with EPR-800 or EPR-900 resin, EPH-300 provides a controlled, low-heat curing profile designed for thick pours, high-mass fills and structural applications where dimensional stability and low shrinkage are critical.
EPH300’s extended pot life and reduced exotherm make it ideal for applications that would overheat, crack or distort with standard hardeners.
KEY FEATURES
3:1 mix ratio with EPR-800 or EPR-900
Very low exotherm — safe for deep pours and large volumes
Long pot life for complex assemblies and large repairs
Low shrinkage and high dimensional stability
High compressive strength after full cure
Excellent adhesion to concrete, steel, timber and composites
Ideal for structural fills and thick casting applications
Smooth, even cure across large cross-sections
TYPICAL APPLICATIONS
Marine & Structural
Transom rebuilds
Stringer replacement
Bulk fill in composite hulls
Structural bonding of heavy sections
Void and cavity filling in boats or FRP structures
Industrial & Civil
Grouting pockets and anchor blocks
Steel plate bedding
Machine base repairs
Heavy structural casting
Large mass stabilisation
Concrete & Flooring
Deep crack injection fills
Mortar replacement
Deep bedding repairs
Large-volume floor patching
Casting Applications
Deep casting blocks
Industrial tooling shapes
Thick decorative castings
Slow-cure colour and clear pours
EPH-300 is the preferred choice wherever depth, mass or structural thickness exceed the safe limits of standard 2:1 system.
TECHNICAL PERFORMANCE
Mix Ratio:
3:1 by volume (EPR-800/EPR-900 : - EPH-300)
Pot Life:
7–9 hours at 25°C
Allows safe large volumes without runaway heat.
Viscosity:
5–15 mPa @ 25°C
Almost water-thin — exceptional flow and penetration.
Cure Behaviour:
Very slow, controlled gel time
Excellent thermal stability
Low peak temperature even in large masses
Minimal shrinkage
High final crosslink density
Long open time allows repositioning and complex assemblies
Mechanical Properties:
High compressive strength after full cure
Strong adhesion to steel, concrete, timber and composites
Excellent dimensional accuracy in thick sections
APPEARANCE
EPH-300 is a low-colour, slow-reacting hardener that cures to a smooth, high-strength finish with minimal heat distortion.
Suitable for Clear, White, Black and Grey UNI-SYSTEM™ resin blends.
EPH-300 Controlled. Strong. Deep-Cure Engineering.
Designed for builders, fabricators, marine repairers and industrial professionals who need a slow, stable, structural-grade cure capable of handling high-volume pours, transom rebuilds and deep infills without overheating or compromising strength.
