THE DEVELOPMENT OF HEAT-RESISTANT PAINTS FOR METALS
Abstract
Experiments with ZnO and di-n-butylamine phosphate resulted in the preparation of heat-resistant coatings, but the coatings were not water resistant. Coatings that were hard, well-bonded, heat resistant, and water resistant were produced repeatedly from a mixture of ZnO, DMHP (dimethyl hydrogen phosphite), and a dispersion of colloidal silica when they were cured at 72 deg F and 75% RH; when cured at 70% or 80% RH, the coatings were not heat resistant. The properties of znO-DMHP-EAP (ethyl acid phosphate) coatings cured at 72 deg F and various relative humidities varied erratically, and in no case was a coating obtained that was both water resistant and heat resistant. Coatings of mixtures of ZnO-DMHP and colloidal silica reach constant weight in less that 2 hr when cured in air at normal temperatures. The weight loss corresponds fairly closely to that calculated for the loss of all methyl groups in DMHP and the water in the silica dispersion. Comparison of several methods of pretreatment of Al panels indicates that sanding and washing with acetone is satisfactory. ZnODMHP-colloidal silica coatings were exposed for over 300 hr in the WeatherOmeter with no apparent deterioration.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 08, 1962
- Accession Number
- AD0287532
Entities
People
- Franklin Alexander
- Marvin Mcgarity
- R. W. Liggett
- Stanley E. Mileski
Organizations
- Southern Research