Which FLUOROSEAL CRC is Right for Your Needs?
Why and how FLUOROSEAL® modified PVDF field applicable coating block-off moisture, moisture laden with acidic and salt ions, and corrosive gases from penetrating into reinforced concrete?
To be effective in protecting the reinforced concrete from concrete carbonation and weathering weakening and rebar corrosion weakening, the coating must at least meet the following requirements:
- Field applicable in coating onto the large areas of exposed reinforced concrete structures. That is by roller or brush or spray coating method and “cure” at ambient.
- The coating must be itself resistant to UV exposure for more than 50 years: so that the protection coating does not need constant maintenance. Preferably, the coating should also block UV from reaching underneath the coating to prevent UV damages to the structure or other coating on the structure.
- The coating must have ability to block moisture penetration inside the concrete. Lesser moisture penetration will prevent the water pockets to be accumulated inside the concrete pores and concrete-rebar interface. Lesser moisture also reduces the possibility of Cl-, Na+ and other salt ions being carried along to cause alkalization and rebar corrosions.
- The coating should have the ability to block corrosive gases such as CO2, H2S from carried by the moisture or penetration and react with the retained waters inside the concrete pores and rebar-concrete interfaces. FLUOROSEAL® coating with PVDF molecular structures are proven to provide the highest barrier capabilities of field applicable coating.
PVDF, PTFE and other highly packed fluorinated polymers are molecularly structured and have been proven to have the highest density and thus lowest molecular pores to provide lowest permeability for moisture and corrosive gases. FLUOROSEAL® concrete and corrosive protection coatings are currently the only field applicable, air-drying PVDF coatings that can be applied by brushing, roller-coating and spraying methods onto large areas of building and infrastructure directly or as top-coating to put immediate stop to further degradation and weakening.
FLUOROSEAL® CRC-V-7150 and CRC-H-7280 have been proven effective and field applicable solution.
Any break or breach into the well protected steel infrastructure causes penetration by salt-spray or ions laden moisture such as salt-fog to cause corrosion. In this above experiment, a fully FBE coated steel bar is cut on both sides. One side is left exposed to simulate loss of protective coating (can be mechanical accident or stress concentration corner) while the other side is coated with FLUOROSEAL® CPC-7150. When the steel pieces in submerged in slight warm (60°C) salt-water to accelerate the penetration and corrosion. The side NOT PROTECTED with the top-coating of FLUOROSEAL® quickly corroded with migrate inward towards the securely coated areas while the exposed steel protected showed no sign of corrosion including the top-coated epoxy surface.
The effectiveness of FLUOROSEAL® corrosion protection capability in blocking corrosive gases and moisture laden with these corrosive ions and acidic elements are demonstrated under the heat-humidity-sulfide exposure test on the bottom right. Uncoated and those coated with acrylic type molecular structure showed extensive corrosion and degradation. The surfaces of the aluminum foil protected by FLUOROSEAL® CPC-7150 modified PVDF is clearly demonstrated.
Besides and beyond being capable in blocking off corrosive gases, moisture and moisture laden with salt ions, the concrete protection coating must also be UV resistant and better yet able to block-off UV for underlying decorative coating or structure. FLUOROSEAL® Concrete Protection Coating CRC-V-7150 and CRC-H-7280 are the ONLY FIELD APPLICABLE (VOC Free) 70% PVDF (Polyvinylidene fluoride) Proven to Block Moisture-Water, Corrosive Elements, and UV Molecular Stability for >60 Years.
The above data showing gloss retention is a measurement of the UV resistance or molecular stability when exposed to UV during the sun exposure.
- Typical acrylic, polyurethane and epoxy coating are well-known to subject to molecular damages and thus lost their glossiness.
- Silicone coating (Polysiloxane) while having slightly tighter molecular bonding degrade slower, still molecular damages and degrades substantially.
- C-F molecules in PVDF and FEVE having much highly bonding energy have been proven to be stable for over 60 years under normal solar exposure.
- PVDF coating typically having much higher molecular packing density in the range or 1.6 to 1.8 while FEVE ranges from 1.4 to 1.5 and thus showed much higher barrier to moisture and corrosive gases penetration to provide the unparalleled field applicable corrosion and carbonation-alkalization protection to concrete and rebar.
Product FLUOROSEAL® CRC-V-7130
Product FLUOROSEAL® CRC-H-7280