Belzona 3921
GSC Surface Conditioner
A 2-part zinc epoxy surface conditioner for non-porous substrates prior to Belzona membrane application.
A 2-part, solvent-based zinc epoxy surface conditioner for non-porous surfaces prior to application of Belzona 3111, Belzona 3211 and Belzona 3131. Also used as a holding primer for steel.
- SeriesBelzona 3000 Series
Overview of Belzona 3921
Belzona 3921 (GSC Surface Conditioner) is a two-component, solvent-based zinc epoxy surface conditioner formulated to provide adhesion of Belzona membrane systems to a wide range of non-porous substrates. It is part of the Belzona 3111 (Flexible Membrane), Belzona 3211 (Lagseal) and Belzona 3131 (WG Membrane) systems when applications are made onto non-porous surfaces such as iron, steel, galvanized steel, non-ferrous metals, glass, GRP/FRP and slate.
Due to its zinc-rich epoxy formulation, Belzona 3921 also functions as a holding primer on prepared steel surfaces prior to application of Belzona 5111 or Belzona 5811 protective coatings, and may be used as a stand-alone product for small-area steel protection applications such as coating reinforcing bars in concrete repair work.
Key Benefits
Single-part elastomeric primer required for adhesion of Belzona elastomers
Bonds strongly to virtually any rigid surface
Outstanding resistance to corrosion in salt spray and chemical environments
Easy to mix and apply without specialist tools
Application Areas
What this product handles, grouped by equipment area — each links to the full application.
Roof Problem Areas
3 applications- Roof sheeting & felt conditioning for overcoatingConditioning of glass, slate and synthetic polymer roof sheeting prior to membrane overcoatingLearn more
- Metal substrate conditioning for coatingsSurface conditioning of metal substrates prior to Belzona 3111, 3211 and 3131Learn more
- Rebar protection in concrete repairStandalone protection of reinforcing bar in concrete repairLearn more
Technical Data
Description
- Type
- Two-part, solvent-based zinc epoxy surface conditioner
- Chemical Binder
- Zinc Epoxy
- Distinctiveness
- General surface conditioner with high zinc epoxy content
- Available Colors
- Light Gray (RAL 7040 — nearest reference)
Base Component
- Appearance
- Semi-thixotropic liquid
- Color
- Gray
- Viscosity
- 9 - 11 poise
- Density
- 2.62 - 2.66 g/cm³
Solidifier Component
- Appearance
- Mobile liquid
- Color
- Amber
- Density
- 0.90 - 0.94 g/cm³
- Viscosity (flow cup)
- 55 - 85 sec at 77°F (25°C)
Mixed Properties
- Density
- 2.26 g/cm³
- Appearance / Color
- Gray liquid
VOC Content
- Base
- 3.81 lbs/US gal (456 g/L)
- Solidifier
- 4.91 lbs/US gal (587 g/L)
- Mixed
- 4.05 lbs/US gal (485 g/L)
Coverage Rate (practical)
- Iron / Steel
- 45 sq.ft. (4.2 m²) per kg
- Galvanized Steel
- 54 sq.ft. (5.0 m²) per kg
- Non-ferrous metals
- 60 sq.ft. (5.6 m²) per kg
- Slate
- 38 sq.ft. (3.5 m²) per kg
- Glass
- 60 sq.ft. (5.6 m²) per kg
- Painted surfaces
- 60 sq.ft. (5.6 m²) per kg
- Synthetic polymer roof sheeting
- 60 sq.ft. (5.6 m²) per kg
Adhesion & Mechanical
- Cross Hatch Adhesion (BS 3900 Part E6)
- 100% pass
- Falling Weight Impact (ASTM D2794)
- Greater than 78 inch-lbs
Packaging
- Available Unit Sizes
- 500 g, 5 kg (sizing and availability may vary by region)
- Shelf Life
- 5 years separate components, stored 32°F - 86°F in unopened containers
Service Temperature Limits
- Application Temperature Range
- 50°F (10°C) to 86°F (30°C)
- If chemical immersion is anticipated, overcoat with Belzona 5111 or 5811
Mixing & Application
Gallery
Related Products
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