Tunnels under the sea, above river and passing through mountains are some of most vulnerable reinforced concrete structures subjected to high humidity, trapped exhaust corrosive gases:
Tunnels are some of the most expensive infrastructures to build and required extensive repair and rebuild periodically due to concrete weakening and rebar corrosion. Tunnels subject to extreme moisture laden environment. Tunnels with vehicle traffic and passing under the sea are particularly vulnerable to the exhaust corrosive gases and ionic salts in salt-fog and salt-spray.
Tunnels built with reinforced concrete are exposed to vehicle daily exhaust corrosive gases can also benefits with FLUOROSEAL® CRC-V-7130 coating that blocks these acidic corrosive gases and moisture laden with corrosive salt ions low maintenance protection to this important infrastructure.
Even though tunnels are not subjected to UV exposure, unless the tunnels are protected with extensive Protective and decorative finishings and panels in all sides, the exposed reinforced concrete are vulnerable to the extensive moisture laden with corrosive elements that can penetrate and causes concrete weakening and rebar corrosion.
For the field applicable coatings that can be brushed, roller-coated, and spray coated onto concrete and metal surfaces with or without existing coatings for immediate stoppage of further damages from the corrosion and carbonation, FLUROSEAL® modified PVDF have been proven with unparalleled successes. It also has documented scientific proof from molecular structure basis in blocking penetrations of moisture, moisture laden with acidic and ionic corrosive elements, and corrosive gases.
The following charts represent a summary of the known effects from polymer molecular structure in relationship to water and oxygen gas permeability. Water having one of the lowest kinetic diameters (akin to the smallest bouncing balls) penetrate the polymer film as barrier depending on their molecular packing structure (somewhat related to its density).
That is, water permeability is a good measure for the moisture penetration.
- FLUOROSEAL® with PVDF as primary molecular structure has similar molecular packing as LCP and better than PVDC (“Saran Wrap” that is used for food freshness preservation.)
- It is at least 1,000 times or 4 orders of magnitudes better barrier than acrylic, epoxy or polyurethane coating.
Oxygen Permeability is a good measurement for the corrosive gas penetration through the coating.
- The Kinetic diameter of O2 is similar to that of CO2, NO, and H2S and much smaller than Cl2, SO
- The kinetic diameters can be analog to bouncing balls, smaller it is, easier for it to penetrate a polymer coating.
- In this case, FLUOROSEAL® with PVDF as primary molecular structure, has at least 4-6 orders of magnitudes (or thousands of times) better in performing as barrier to prevent these gases from penetration.
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.