Effect of Process Parameters on Pot Life of Solid Propellant Composite Based on Hydroxyl-Terminated Polybutadiene: A Short Review

Document Type : compile

Author

Assistant Professor/Imam Hussein Comprehensive University

Abstract

Effect of process parameters on pot life of composite solid propellant based on hydroxyl- terminated polybutadiene (HTPB) is an important issue in the production of medium and large scale grains. In this article, the prolonging of pot life of composite solid propellant based on HTPB was studied through process control of parameters such as: mixing temperature, casting temperature, NCO/OH ratio (r), mixing speed and time, presence of micro or nano-sized aluminum and ammonium perchlorate (AP) and feeding sequence of solid loading. In literature, it is reported that increases in casting temperature result in curing progress and subsequently increases the slurry viscosity. Therefore, it is preferred to increase the pot life by reducing the casting temperature in adjusting the curing process. The curing rate is increased by increasing the NCO/OH ratio, which can be attributed to the growth of molecular weight, branching and more crosslinking of the polymer chain. It is reported that viscosity build up is transformed from linear plot to exponential, when (μAPf:μAPc) ratio is exceeded than 1:4. Moreover, by acquiring a 1:2 ratio of (μAPf:μAPc), viscosity is increased which makes casting difficult. By studying the increases in feeding rate it is shown that the pot life is mainly determined by feeding rate of (Al+2APc+2APf) for (μAPf:μAPc) ratio of 1:2 and 1:3 and to feeding rate of (APc+APf+APc+APf+2Al) for (μAPf:μAPc) ratio of 1:4.

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Main Subjects


1. Sekkar V., Ambika D., and Ninan K., Rheo-Kinetic Evaluation on the Formation of Urethane Networks Based on Hydroxyl-Terminated Polybutadiene, J. Appl. Polym. Sci., 79, 1869- 1876, 2001.
2. Rao M., Scariah K.,Varghese A., Naik P., Swamy K., and Sastri K., Evaluation of Criteria for Blending Hydroxy Terminated Polybutadiene (HTPB) Polymers Based on Viscosity Build-Up and Mechanical Properties of Gumstock, Eur.
Polym. J., 36, 1645-1651, 2000.
3. Mahanta A. and Monika G., Analysis of Torque-Time Profile of Composite Propellant Slurry: Isothermal Cure Kinetics and Evaluation of Pot Life, J. Indian Counc. Chem., 26, 94-99, 2009.
4. Sekkar V. and Raunija T.S.K., Hydroxyl-Terminated Polybutadiene- Based Polyurethane Networks as Solid Propellant
Binder-State of the Art, J. Propul. Power., 31, 16-35, 2014.
5. Mahanta A.K. , Dharmsaktu I., and Pattnayak P.K., Rheological Behaviour of HTPB-Based Composite Propellant: Effect
of Temperature and Pot Life on Casting Rate, Defence Sci. J., 57, 435-443, 2007.
6. Muthaiah R., Manjari R., Krishnamurthy V.N., and Gupta B.R., Rheology of HTPB Propellant: Effect of Mixing Speed
and Mixing Time, Defence Sci. J., 43, 167-176, 1993.
7. Nair C.R., Prasad C.D.V., and Ninan K.N., Effect of Process Parameters on the Viscosity of AP/Al/HTPB Based Solid Propellant Slurry, J. Energy Chem. Eng., 35, 1-10, 2013.
8. Sekkar V., Alex A.S., Kumar V., and Bandyopadhyay G.G., Pot Life Extension of Hydroxyl Terminated Polybutadiene
Based Solid Propellant Binder System by Tailoring the Binder Polymer Microstructure, J. Macromol. Sci., Part A: Pure Appl.
Chem., 54, 171-175, 2017.
9. Chai T., Liu Y.C., Ma H., Yu Y.W., Yuan J.M., Wang J.H., and Guo J.H., Rheokinetic Analysis on the Curing Process of
HTPB-DOA-MDI Binder System, IOP Conference Series: Materials Science and Engineering, Hangzhou, China, 20–23
May, 1-8, 2016.
10. Iqbal M.M. and Liang W., Modeling of Composite Propellant Properties Based on Polymer Rheology, 42nd AIAA/ASME/
SAE/ASEE Joint Propulsion Conference and Exhibit, Sacramento, California, 1-8, 9-12 July, 2006.
11. Kumari A., Mehilal J.S., Jain M., and Bhattacharya B., Nano- Ammonium Perchlorate: Preparation, Characterization, and Evaluation in Composite Propellant Formulation, J. Energy Mater., 31, 192-202, 2013.
12. Maggi F., Curing Viscosity of HTPB-Based Binder Embedding Micro and Nano-Aluminum Particles, Propell. Explos.
Pyrot., 39, 755-760, 2014.
13. Pang W.Q., Fan X.Z., Zhao F.Q., and Zhang W., Xu H.-X., Yu H.-J., Xie W.-X., Yan N., and Liu F.-L., Effects of Different Nanometric Particles on the Properties of Composite Solid Propellants, Propellants Explos. Pyrotech., 39, 329-336, 2014.
14. Kumari A., Kurva R., Jain S., Jawalkar S.N., Mehilal M., Singh P.P., and Bhattacharya B., Evaluation of Nanoaluminum
in Composite Propellant Formulation Using Bicurative System, J. Propul. Power, 31, 393-399, 2015.
15. Rodić V., Dimić M., Brzić S., and Gligorijević N., Cast Composite Solid Propellants with Different Combustion Tabilizers,
Sci. Tech. Rev., 65, 3-10, 2015.