| || Waterproofing materials for Ammonium Nitrate
Author : Damse, R.S.
Source : Defence Science Journal ; Vol:54(4) ; 2004 ; pp 483-492
Subject : 623.4 Armaments and Ballistics;623 Military Science and Engineering
Keywords : Hygroscopicity;Phase transition;Waterproofing ability;Mineral jelly;Ammonium nitrate;High energy materials;Coating materials
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.