FAIRCOAT Anti-Carbonation, Protective, Decorative Coatings for Interior & Exterior concrete surfaces
In today world, concrete is the most used material / product in construction industry. Concrete structures exposed to atmospheric carbon dioxide emitted from various sources, in presence of moisture / water, atmospheric carbon dioxide diffuses slowly through the concrete and the process of carbonation is initiated, the pH of concrete slowly turns acidic and starts rusting the reinforcing steel bars. Anti-carbonation coatings are used as surface treatments that have a high resistance to carbon dioxide. They shield the concrete from carbonation by acting as a barrier. For example, Fairmate’s ‘FAIRCOAT’ is well known and is protecting several renowned structures in India.
Features of FAIRCOAT Anti-Carbonation Coatings
FAIRCOAT is a smooth protective, decorative anti-carbonation coating for interior & exterior surfaces with exceptional weathering characteristics. It is based on aliphatic elastomeric acrylic. It has been specially designed for the decoration and protection of concrete against attack from atmospheric carbon dioxide, airborne chlorides, acid rain, weathering etc. When it is applied on surface, it forms a flexible layer allows the surface to breath and acts as carbon dioxide barrier thus protecting the concrete in aggressive weather conditions. Properties include the following:
• Anti-carbonation properties
• Excellent waterproof coating
• High flexibility with crack bridging capabilities up to 2mm
• UV resistant
• Excellent bonding characteristic with the substrate
• Chloride ion diffusion is zero as per ASTM C 1202
• Resistance to carbon dioxide diffusion is > 50mm thickness of equivalent air layer as per EN 1062
• Non-toxic and non-flammable
• Good weathering properties (anti-algal & anti-fungal).
Concrete is a highly alkaline material and if un-carbonated it has a pH in the region of 12.6. Carbonation starts on the surface of the concrete and can ultimately reach the depth of the steel reinforcement within the concrete. The alkaline state of the concrete provides a passive resistive layer to the surface of the steel reinforcement that prevents corrosion.
Once concrete comes into contact with carbon dioxide and other pollutants within the air, then a reaction may occur. Carbon dioxide can form carbonic acid with the water in the cement that then neutralizes the alkaline state of the concrete. If this happens, then carbonation moves through the concrete as a front that gradually reduces the pH value to 8pH; neutral is 7pH. However, corrosion to the reinforcement can occur if the pH value falls below 11pH.
Carbonation occurs when carbon dioxide reacts with calcium hydroxide of concrete and deposits as calcium carbonate, which reduces the protection of embedded steel reinforcement. This, in turn, results in reinforcing steel becoming susceptible to attack by water and oxygen, causing corrosion of the steel and eventually spalling of the concrete.
Application Areas
Existing Building & Bridges: It can be applied as a protective coating in existing buildings and bridges to protect them from carbon dioxide, air borne chloride, and rain.
New Buildings & Bridges: FAIRCOAT can be applied as an anti-carbonation coating in new buildings and bridges, which will enable it to resist attack by carbon dioxide, airborne chloride, and rain.
Interior Decoration of Buildings: As FAIRCOAT is non-flammable and has excellent waterproof characteristics, it can be used in interior decoration.
To achieve effective anti-carbonation coating, a two-coat application is recommended. FAIRCOAT covers 3-4m2 per kg with a recommendation of two coats for a dark shade. The surface texture and porosity must be taken into account while estimating quantities.
For more details visit: www.fairmate.com or email: enquiry@fairmate.com
