Waterproofing Materials for Ammonium Nitrate

Abstract

This study explores the possibility of overcoming the problem of hygroscopicity of ammonium nitrate by coating the particles with selected waterproofing materials. Gravimetric analysis of
the samples of ammonium nitrate coated with eight different waterproofing materials, vis-a-vis, uncoated ammonium nitrate, were conducted at different relative humidity and exposure
time. The results indicate that mineral jelly is the promising waterproofing material for ammonium nitrate among the materials tested, viz, calcium stearate, dioctyl phthalate, kaoline, diethyl
phthalate, dinitrotoluene, shelac varnish, and beeswax. Attempts were made to confirm the waterproofing ability of mineral jelly to ammonium nitrate using differential thermal analysis
and x-ray diffraction patterns as an experimental tool. Suitability of mineral jelly as an additive for the gun propellant was also assessed on the basis of theoretical calculations using THERM
program.