Nitrocellulose-nitroglycerine double-base propellants

A third type of propellant, the composite modified-double-base propellant, represents a combination of the other two types. These propellants are made from mixtures of nitroglycerine and nitrocellulose or similar materials, but with crystalline oxidizers such as ammonium perchlorate also included in the matrix. 

The approach taken in the development of an analytical model for the combustion of double-base propellants has been based on the decomposition behavior of the two principal propellant ingredients, nitrocellulose and nitroglycerin. The results of several studies reviewed by Huggett (HI2) and Adams (Al) show that nitrocellulose undergoes exothermic decomposition between 90° and 175°C. In this temperature range, the rate of decomposition follows the simple first-order expression... 

Double base propellant. A propellant based on nitrocellulose and nitroglycerine. 

Double-based propellants are a mixture of nitrocellulose and nitroglycerine. This mixture increases the pressure of the gas inside the gun barrel. Double-base propellants are used in pistols and mortars. Some disadvantages of using double-base propellants is the erosion that this mixture causes to the gun barrel due to higher burn temperatures and the presence of muzzle flash. 

Triple-based propellants are mixtures of nitroguanidine, nitrocellulose, and nitroglycerine. The mixture reduces the muzzle flash observed with double-based propellants, reduces the burn temperature, which protects the gun barrel, and increases the gas volume. Triple-based propellants are used in tank guns, large caliber guns, and some naval weapons. 

M55 rockets pose the greatest storage risk because they contain approximately 20 pounds of M28 propellant, a double-base propellant composed of nitroglycerine, nitrocellulose, plasticizers, a bum-rate modifier, and a stabilizer. The exact composition is given in Table 1-4. The propellant slowly decomposes exother-... 

Since the energy contained within double-base propellants is limited because of the limited energies of nitrocellulose (NC) and nitroglycerin (NG), the addition of ammonium perchlorate or energetic nitramine particles such as HMX and RDX increases the combustion temperature and specific impulse. Extensive experimental studies have been carried out on the combustion characteristics of composite-modified double-base (CMDB) propellants containing AP, RDX or HMX parhclesli- l and several models have been proposed to describe the burning rates of these pro-... 

Nitropolymers composed of -O-NO2 functions and hydrocarbon structures are pyrolants that produce fuel-rich products accompanied by exothermic reaction. Typical nitropolymers are mixtures of nitrocellulose, nitroglycerin, trimethylolethane trinitrate, or triethylene glycol dinitrate, similar to the double-base propellants used in rockets and guns. Mixtures of these nitropolymers are formulated as fuel-rich pyrolants used in ducted rockets. This class of pyrolants is termed NP pyrolants. 

Of these, the most successful appeared in 1887 when Alfred Nobel patented a nitrocellulose propellant plasticised with nitroglycerine. Known as a double-base propellant, it is virtually smokeless, with a very high specific impulse as compared to gunpowder. Single-base propellants were developed in 1865 and 1890 by Schultz and Vieille respectively and these took the form of gelatinised nitrocellulose for use in firearms and mortars. 

The same author [27] gives some data on a propellant which is intermediate between composite and double base propellants. It is composed of ammonium perchlorate and a nitroglycerine-nitrocellulose powder (double base powder). 

In order to raise the Q value of single-base propellants and to increase the pressure of the gas inside the gun barrel, nitrocellulose is mixed with nitroglycerine to form double-base propellants. Double-base propellants have a Q value of about 4500 J g 1 and are used in pistols and mortars. The disadvantage of double-base gun propellants is the excess-... 

Solid propellants may be classified as monopropellants or composite propellants. Monopropellants are substances in which the fuel and oxidizer are both contained within the same molecule or at least in a single phase. These materials may either burn slowly at subsonic rates or may decompose rapidly in detonation. Depending on the use to which this type of material is put, it may be classified either as propellant or high explosive. In general, useful monopropellants are difficult to detonate. The typical example of a monopropellant is the so-called double-base propellant. This substance consists of nitrocellulose which has been colloidized by nitroglycerine along with various minor constituents which have been added to... 

W.A. Schmeling, Reclamation of Nitrocellulose and Nitroglycerine from Scrap Double-Base Propellant , Prog Rept No 5, Badger Ordn Works, Baraboo (1957) 21) D.R. Brown,... 

Propellants that contain nitrocellulose as the only oxidizer are referred to as single base and propellants that contain both nitrocellulose and nitroglycerine (or some other explosive plasticizer) as double base. Triple-based propellants are produced when substantial quantities of an organic, energy-producing, crystalline compound such as nitroguanidine are incorporated in double-based propellants. Triple-based propellants are unlikely to be encountered in small arms ammunition. 

High explosives may be class d according to their physical properties as powdery, meltable, semi-meltable and plastic. Propellants may be grouped on the basis of chemical composition into gun powder and similar mixtures, nitrocellulose (single base) and nitroglycerine (double base) powders, With respect to their uses and some properties they are divided into black powder, smokeless and flashless powders, and rocket propellants. 

It is a satisfactory gelatinizer for nitrocellulose and is a powerful explosive, comparable to Cyclonite and PETN. Double base propellants based on DINA instead of nitroglycerine are named Alba-... 

Explosive material with low rate of combustion. May be either solid or liquid. Will burn smoothly at uniform rate after ignition without depending on interaction with atmosphere. Single base propellant consists primarily of matrix of nitrocellulose. Double base propellant contains nitrocellulose and nitroglycerine. Composite propellant contains oxidizing agent in matrix of binder. 

Nitramine (RDX or HMX) oxidizer Homogeneous colloidal propellant consisting of nitrocellulose dissolved in plasticizer comprised of nitroglycerine and inert materials Composite or double-base propellant in which polymer is dissolved in plasticizier... 

Nobel patented a double-base propellant produced by gelatinizing nitroglycerine with nitrocellulose. 

Double-base propellants. Double-base propellants are made of gelatinized or plasticized nitrocellulose with another liquid propellant or explosive. This second type of propellant is nitroglycerine. Other nitrate esters may also be used in place of nitroglycerine. Also, dinitrotoluene... 

Nitroglycerine is one of the most important and most frequently used components of explosive materials together with nitroglycol, it is the major component of gelatinous industrial explosives. In combination with nitrocellulose and stabilizers, it is the principal component of powders, gun propellants and smokeless solid rocket propellants (- double base propellants). 

Nitroglycerin is used to formulate explosives and is mixed with nitrocellulose as with double-base propellants. However, the mass fraction of NC is 0.06 - 0.08 for explosives and 0.3 - 0.6 for double-base propellants. Though both materials are homogeneous in their physical structures, the energy density of explosives is higher than that of double-base propellants because of the high mass fractions of NG. 

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