Belzona 4981
Magma TX Conditioner (High-Temp)
A two-component thixotropic conditioner for masonry, metallic, and non-metallic substrates ahead of Belzona 4000 Series and high-temperature coatings.
A two-component thixotropic resin system used as a substrate primer ahead of Belzona 4000 Series products and as a conditioner for non-metallic surfaces ahead of Belzona high-temperature coatings.
- SeriesBelzona 4000 Series
- Documents2
Overview of Belzona 4981
Belzona 4981 (Magma TX Conditioner — High-Temp) is a two-component, thixotropic resin system with excellent adhesion to masonry and metallic surfaces. The system is engineered as a substrate primer and conditioner ahead of Belzona 4000 Series products, and additionally serves as a conditioner for non-metallic surfaces ahead of Belzona high-temperature coatings.
The 100:28 by weight (3:1 by volume) Base-to-Solidifier system delivers Shore D 80 hardness (ambient cure plus 2 hours at 100°C) and HDT increasing from 111°F (44°C) at ambient cure to 266°F (130°C) at post-cure — a substantial heat-distortion improvement that protects high-temperature coatings from thermal stress at the bond line. Sag index minimum 50 mil (1.25 mm), with coverage of 75 sq.ft. (7.0 m²) per 3 kg unit.
Key Benefits
Exceptional compressive strength for load-bearing applications and demanding mechanical environments
Bonds strongly to virtually any rigid surface
100% solids formulation reduces health and safety risks in confined spaces with no shrinkage on cure
No solvents, no shrinkage during cure
Application Areas
What this product handles, grouped by equipment area — each links to the full application.
Floor Problem Areas
1 applicationTechnical Data
Composition
- Type
- Two-component, thixotropic resin system substrate conditioner and primer
- Mixing Ratio by Weight (Base : Solidifier)
- 100 : 28
- Mixing Ratio by Volume (Base : Solidifier)
- 3 : 1
Components
- Base
- Opaque thixotropic paste, density 1.2 g/cm³
- Solidifier
- Clear amber liquid, density 1.03 g/cm³
Mixed Properties
- Sag Index
- Minimum 50 mil (1.25 mm)
Application & Coverage
- Working Life at 77°F (25°C)
- 30 minutes from commencement of mixing
- Coverage Rate (3 kg unit)
- 75 sq.ft. (7.0 m²)
Compressive Strength (ASTM D659)
- Ambient cure
- 5,530 psi (38.1 MPa)
- Post-cure
- 7,380 psi (32.9 MPa)
Flexural Strength (ASTM D790)
- Ambient cure
- 5,350 psi (36.9 MPa)
- Post-cure
- 4,770 psi (32.9 MPa)
Adhesion
- Tensile Shear, grit blasted steel (ASTM D1002, ambient cure)
- 2,250 psi (15.5 MPa)
- Tensile Shear, grit blasted steel (post-cure)
- 2,070 psi (14.3 MPa)
- PosiTest Pull-off, dry concrete (ASTM D4541)
- 600 psi (4.1 MPa)*
- * Cohesive failure within substrate — bond exceeds substrate strength
Hardness
- Shore D (ASTM D2240, ambient cure plus 2 hours at 100°C)
- Minimum 80
Impact Resistance (Izod Reverse Notched, ASTM D256)
- Ambient cure
- 0.75 ft.lb/in (40.1 J/m)
- Post-cure
- 0.87 ft.lb/in (46.8 J/m)
Heat Resistance
- HDT (ambient cure, ASTM D648, 264 psi fiber stress)
- 111°F (44°C)
- HDT (post-cure)
- 266°F (130°C)
Shelf Life
- Separate Base and Solidifier components have a 5-year shelf life from date of manufacture in original unopened containers stored between 32°F (0°C) and 86°F (30°C)
Working Life
From commencement of mixing, use within:
- 59°F (15°C)
- 55 minutes
- 68°F (20°C)
- 45 minutes
- 77°F (25°C)
- 32 minutes
Curing Time
Allow Belzona 4981 to solidify before subjecting it to the conditions indicated:
At 59°F (15°C)
- Resist pedestrian traffic
- 12 hours
- Full mechanical hardness
- 48 hours
- Full chemical resistance
- 10 days
At 77°F (25°C)
- Resist pedestrian traffic
- 8 hours
- Full mechanical hardness
- 24 hours
- Full chemical resistance
- 5 days
Overcoating Window
Maximum overcoat time after conditioning:
- With Belzona 4181
- 4 hours (all temperatures 59°F–77°F)
- With Belzona 5892
- 6 hours (all temperatures 59°F–77°F)
Service Temperature Limits
- Working Life at 77°F (25°C)
- 30 minutes — use all material within this time
- Heat Distortion Temperature (ambient cure, ASTM D648 264 psi fiber stress)
- 111°F (44°C)
- Heat Distortion Temperature (post-cure)
- 266°F (130°C)
- Storage Temperature
- 32°F (0°C) to 86°F (30°C) in unopened containers
- Service temperatures determined by overcoat selection — refer to the relevant Belzona overcoat product PSS for thermal limits of the cured system
Product PDFs
Gallery
Frequently Asked Questions
What is Belzona 4981 (Magma TX Conditioner High-Temp) used for?
Belzona 4981 is a high-temperature variant of the Magma TX Conditioner, formulated to be applied to concrete and stone substrates prior to high-temperature or acid-resistant Belzona 4000 Series repair materials and coatings. It penetrates the substrate to seal porosity and improve adhesion under elevated service conditions.
What is the mixing ratio of Belzona 4981 (Magma TX Conditioner High-Temp)?
The mixing ratio of Belzona 4981 (Magma TX Conditioner High-Temp) is 100 : 28 (Base : Solidifier) by weight and 3 : 1 (Base : Solidifier) by volume. Please see the Product Specification Sheet (PSS) for more information.
How do you apply Belzona 4981 (Magma TX Conditioner High-Temp)?
To apply Belzona 4981, the substrate must be clean, firm, and dry, free of any paint, oils, or other contaminants. Add the entire contents of the Solidifier to the Base unit and mix thoroughly until completely homogeneous. From the commencement of mixing, apply Belzona 4981 to the prepared surface within 30 minutes using a short-bristled brush or roller, ensuring full penetration into the substrate. Apply the subsequent high-temperature or acid-resistant Belzona system wet-on-tacky as specified in the relevant Instructions for Use. Please see the Instructions for Use (IFU) for more information.
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