Abstract: Disclosed is a method of enhancing the rate of consumption of a propellant s a result of having shrink tubes or spheres embedded in the propellant. The shrink tubes suitable for use in this method are derived from various polyurethane or polyolefin resins which undergo shrinkage when exposed to moderate heat. The mechanism of enhancement derives from the fact that when the flame front reaches the shrink tube or sphere, the tube or sphere undergoes shrinkage, and thus, exposes additional propellant surface to the burning process. High burning rate are achieved because of the apparent reduced overall propellant web created by the presence of and resultant action to these shrink tubes or spheres.A modification of the method of this invention is to embed these plastic tubings in the propellant, raise the temperature of the propellant mass to a temperature at which the tubing will undergo shrinkage.

Abstract: Ultra-ultrahigh burning rate composite modified double-base propellants are btained by use of porous ammonium perchlorate as a replacement for the ultra-ultrafine ammonium perchlorate. The porous ammonium perchlorate is used in combination with aluminum powder fuel and aluminum staples, nitroglycerin as an explosive plasticizer, triacetin as a non-explosive plasticizer, stabilizers selected from resorcinol and 2-nitrodiphenylamine and other selected additives for achieving desired processing, mechanical, ballistic, and other properties of the propellant.

Abstract: Mechanical enhancement of the burning rate of solid propellants is achieved y the incorporation of limited percentages of gas-generated-expandable beads into the solid propellant composition during propellant mixing and which are chemically crosslinked during propellant curing to a solid propellant grain. When the flame front reaches an individual bead during propellant grain burning, the bead which contains a blowing agent selected from 4-toluenesulfonyl hydrazide and 4,4'-oxybis(benzenesulfonyl hydrazide) and coated with a bead forming material consisting of about 95 parts by weight hydroxyl-terminated polybutadiene prepolymer, of about 5 parts by weight of trimethylolpropane, and of about 6 parts by weight of isophorone diisocyanate expands to several times its volume and ruptures. Bead expansion or rupture causes a disruption of the propellant's surface, and the flame can penetrate into the propellant. The penetration results in a major increase in burning rate.