Modeling and rheology of HTPB based composite solid propellants

• Published in: Polymer composites Vol. 19; no. 4; pp. 463 - 472
• Main Authors: Erişken, Cevat, Göçmez, Ahmet, Yilmazer, Ülkü, Pekel, Fikret, Özkar, Saim
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc., A Wiley Company 01-08-1998; Willey
• Subjects: Application fields; Applied sciences; Chemical industry and chemicals; Exact sciences and technology; Industrial chemicals; Polymer industry, paints, wood; Powders, propellants, explosives; Technology of polymers; Viscosity; Experimental test; Property composition relationship; Solid propellants; Binders; Composite propellant; Modeling; Optimization; Particle size distribution; Packing; Manufacture; Butadiene(hydroxy) polymer; Rheological properties
• ISSN: 0272-8397; 1548-0569
• DOI: 10.1002/pc.10121

The propellant with the minimum viscosity required for a defect‐free casting can be obtained by proper selection of the size and fractions of solid components leading to maximum packing density. Furnas' model was used to predict the particulate composition for the maximum packing density. Components with certain size dispersions were combined to yield a size distribution that is closest to the optimum one given by Furnas for maximum packing. The closeness of the calculated size distribution to the optimum one was tested by using the least square technique. The results obtained were experimentally confirmed by viscosity measurement of uncured propellants having HTPB binder and trimodal solid part accordingly prepared by using aluminum (volumetric mean particle diameter of 10.4 μm) and ammonium perchlorate with four different sizes (volumetric mean particle diameters: 9.22, 31.4, 171, and 323 μm). The experimental measurements showed that the compositions for the minimum viscosity are in good agreement with those predicted by using the model for maximum packing. The propellant consisting of particles with mean diameters of 10.4, 31.4, and 323 μm was found to yield the minimum viscosity. This minimum viscosity was observed when the fraction of the sizes with respect to total solids was 0.141, 0.300, and 0.559, respectively.