CORROSION TESTING OF UREA-FORMALDEHYDE FOAM INSULATING MATERIAL.

Two tests of the corrosiveness of urea-formaldehyde (UF) foam insulating materials were compared: Timm test in which test coupons are foamed in place, and the Canadian test, in which blocks of foam, already set are placed in contact with test coupons. The corrosion rate in both tests is calculated from weight losses. Steel probes, which measure corrosion rate from changes in the electrical resistance, were also foamed along with the coupons in the Timm test. The corrosion rates of galvanized steel coupons in the Canadian test in several cases exceeded the failure value. In the Timm test, the corrosion rates averaged over the whole test period were quite low. The corrosion rates of copper and aluminum in both tests were quite low. Recommendations for a corrosion-test procedure for UF foam were made, in particular that two corrosion tests should be conducted, one for foam while curing and one for after it has stabilized.