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This paper presents an overview of a modified composite propellant formulation to meet future requirements. The composite propellant mixtures were prepared using nitro functionalized Hydroxyl-Terminated Polybutadiene (Nitro-HTPB) as a novel energetic binder and addition of energetic plasticizer. The new propellant formulation was characterized and tested. It was found that the Nitro-HTPB propellant with and without energetic plas-ticizer exhibited high solid loading, high density, and reasonable mechanical properties over a wide range of temperatures. It was shown that the burning rate of Nitro-HTPB propellant is up to 40% faster than that of the HTPB propellant. These results are encouraging and suggest that it should be possible to improve the ballistic performance of popular HTPB propellants through use of the studied Nitro-HTPB binder.

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A series of novel aromatic poly(ester-etherimide)s with inherent viscosity values of 0.44-0.74 dL g À1 were prepared by the diphenylchlorophosphate-activated direct polycondensation of an imide ring-containing diacid namely 5-(4-trimellitimidophenoxy)-1-trimellitimido naphthalene (1) with various aromatic dihydroxy compounds in the presence of pyridine and lithium chloride. Owing to comparison of the characterization data, an ester-containing model compound (2) was also synthesized by the reaction of 1 with phenol. The model compound 2 and the resulted polymers were fully characterized by FT-IR and NMR spectroscopy. The ultraviolet k max values of the poly(ester-ether-imide)s were also determined. The resulting polymers exhibited an excellent organosolubility in a variety of high polar solvents such as N,N-dimethylacetamide, N,N-dimethylformamide, dimethyl sulfoxide, and N-methyl-2-pyrrolidone. They were soluble even in common less polar organic solvents such as pyridine, m-cresol, and tetrahydrofuran on heating. Crystallinity of the polymers was estimated by means of wide-angle X-ray diffraction. The resulted polymers exhibited nearly an amorphous nature. From differential scanning calorimetry thermograms, the polymers showed glass-transition temperatures between 221 and 245 C. Thermal behaviors of the obtained polymers were characterized by thermogravimetric analysis, and the 10% weight loss temperatures of the poly(ester-ether-imide)s were found to be over 410 C in nitrogen.