Hydrocarbon binders

In France, bitumen belong to a category of products called "hydrocarbon binders . They are defined and classified in the French Standard, NF T 65000. The hydrocarbon binders comprise ... 

Mayo, The Chemistry of Aging of Hydrocarbon Binders in Solid Propellants , CP lA Publ 262, Johns Hopkins Univ, Silver Spring (1975)... 

Another class of hydrocarbon binders used in propints are the carboxy-terminated polybutadiene polymers which are cross-linked with either tris[l-(2-methyl)aziridinyl] phosphine oxide (MAPO) or combinations with phenyl bis [l -(2-methyl)aziridinyl] phosphine oxide (Phenyl MAPO). Phenyl MAPO is a difunctional counterpart of MAPO which makes possible chain extension of polymers with two carboxylic acid groups. A typical propint formulation with ballistic properties is in Table 11 (Ref 83) Another class of composites includes those using hydroxy-terminated polybutadienes cross-linked with toluene diisocyanate as binders. The following simplified equations illustrate typical reactions involved in binder formation... 

Hydrazinium diperchlorate (HP2) is one of the higher energetic oxidizers considered for use in composite solid propints with hydrocarbon binders. Its other advantages include high density, high burning rate, and moderate projected cost. Its shortcomings include relatively poor stability to vibrational and thermal shock... 

Since these double-base proplnts consist essentially of a single phase which bears the total load in any application of force, their mechanical property behavior is significantly different from composite proplnts. In the latter formulations, the hydrocarbon binder comprises only about 14% of the composite structure, the remainder being solid particles. Under stress, the binder of these proplnts bears a proportionately higher load than that in the single phase double-base proplnts. At small strain levels, these proplnts behave in a linear viscoelastic manner where the solids reinforce the binder. As strain increases, the bond between the oxidizer and binder breaks down... 

The burning rates of standard aluminized hydrocarbon binder composite proplnts may be increased significantly not only with ferrocene derivatives but also with compatible carborane-type burning rate additives. However, most ferrocene derivatives are volatile solids or liquids which have a tendency to evaporate from the proplnt during storage, thereby degrading ballistic performance. Rudy (Ref 71) minimized this problem by the use of polynuclear ferrocene... 

The use of ultra-fine AP to increase the burning rates of double-base propints has been described previously. This technology has also been used with hydrocarbon binders, but dispersion and high viscosity have presented mixing problems. Fine AP can be conveniently dispersed by slurrying first with a surfactant and an organic liq such as 1,1,2-trichloro-1,2,2-trifluoroethane or normal hexane in a process described by Alley (Ref 58a). Sodium sulfonate... 

The most widely employed thermal reduction process for preparing Mg metal uses PeSi as reducing agent. Mixtures of the substrate, usually calcined dolomite (i.e., MgO, CaO) and PeSi are fabricated into briquettes with a hydrocarbon binder and loaded into Ni-Cr steel (15/28) retorts. After evacuation the retort is subjected to a temperature gradient Mg distills from the hot mixture (at 1150°C) and high-purity Mg crystals collect at the water-cooled end of the retort ... 

Bernard, P.J. "Neutral Cationic Emulsion Containing a Slow-Fracturing Hydrocarbon Binder," Chemical Abstracts. 78(12) 74596f (1973). 

CA 66, 87228q(1967) (High-d, pelleted expls suitable for wet boreholes were prepd from 38—73% AN, 25—60% insol HE sensitizer, and 1—3.5% hydrocarbon binder and waterproofing agent. For example AN 68, TNT 30 paraffin wax 2% were mixed and exttuded under high pressure to give 0.25"inch diam pellets, d 1.4, which detonated at 3500m/sec when packed into 4-inch diam pipe)... 

HMX was first evaluated with hydrocarbon binders (Butarez, a carboxy-terminated polybutadiene, and Butyl rubber) because of their high thermal stability, in addition to the expected advantages of high impetus levels and low flame temps. In the Butarez binder, an 85% HMX level produced an impetus of 370000 ft-lbs/lb and a flame temp of 2540°K. At 84% HMX, the system was under-oxidized, at 86% the flame temp exceeded 2600°K. Because of a less favorable heat of formation, higher HMX loadings were required for the Butyl rubber system, ie, about 87% HMX and 13% Butyl rubber vs 85% HMX and 15% Butarez for an impetus of 370000 ft-lbs/lb. In the hydrocarbon formulations, the Butarez polymer appeared more attractive thermodynamically... 

The influence of -( CH2)-x binder content on the theoretical specific impulse of AP composite containing 8, 12 and 16% aluminum reaches a max at binder contents between 10 and 15% as shown in Fig 16, while the max level of acceptable physical properties occurs at the 10—16% level. Most operational proplnts accept a sacrifice in energy and operate at the 14—16% binder level since this normally determines service life. Differences in hydrocarbon binders as typified by polyurethane, polybutadiene-acrylic acid copolymer, polybutadiene-acrylic acid-acrylonitrile terpolymer and carboxy-terminated... 

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