Technical Bulletin: Salt Spray Test for Acrylic 211

Salt Spray Test for Acrylic 211

3,200 Hour Salt Spray Test for Acrylic 211 (ASTM B117)

American WeatherStar is based on the gulf coast in Mobile, Alabama. Much of our roof coating projects under warranty are located in this region of the country throughout Alabama, Florida, Louisiana, and Texas. The coating restoration systems we develop must perform on roofs near salt air environments. In our history, we have never experienced a failure due to salt air.

We asked the raw material supplier, Dow Chemical, for data verifying our field tests.

American WeatherStar Acrylic 211 utilizes the Dow Chemical Rhoplex EC-1791 as its core component resin. Dow Tech Services sent us the following test results comparing the acrylic coating to a solvent-based epoxy, which is considered the standard in the corrosion resistant coating industry.

The details of the test are presented below. The test process includes applying 15 dry mils of Acrylic 211 to three typical metal substrates a roof coating would be installed over:  galvanized steel, rusted steel, and aluminum. Then, the coating is cut twice in a perpendicular manner. For 3,200 hours, the coating is subjected to a salt spray.

In summary this test goes well beyond what our roof coating is subjected to in the field.  There was no blistering and 100% adhesion after a very harsh test.

Corrosion Resistance

3,200 Hour Salt Spray Test (ASTM B117), two coats at 15 mil total DFT.

Coatings based on: Rhoplex EC-1791 Solvent 2K Epoxy
Blisters (density, size) None Few, 2-5 @ scribe

Adhesion (dry/wet, % remaining)

Cold rolled steel 100/100 100/100
Untreated aluminum 100/100 100/100
Galvanized steel 100/100 100/100
Rusty Steel 100/100 100/100

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