Investigation of Microstructure and Reagents Ratio on the Properties and Structure of Nitrated Hydroxyl Terminated Polybutadiene (Nitro-HTPB)

Document Type : Research Article

Authors

1 Department of Chemical Engineering, Faculty and Research Institute of Technical-Engineering, Imam Hossein Comprehensive University, Tehran, I.R. IRAN

2 Department of Chemistry, Faculty of Basic Sciences, Imam Hossein Comprehensive University, Tehran, I.R. IRAN

Abstract

Hydroxyl-terminated polybutadiene (HTPB) has been widely used as a binder for energetic composites. This neutral binder contains 10 to 15% by weight of these compounds, which if energized, increase the energy content and maintain the physical and chemical properties of the original HTPB to a large extent. The binding of Nitro to the main chain of HTPB (nitration) is a good way to energize it. Nitration common methods, such as nitration with a mixture of acids, dinitrogen pentoxide, and nitromercuration- demercuration, have led to the destruction of the backbone of the polymer. In this research, Nitration with nitrile iodide reagent has been used for the functionalization of HTPB with nitro groups, in which the double bonds and the backbone of resin are not degraded. In order to maintain the unique physical and chemical properties of HTPB, nitration levels are limited to 10 to 15% of double bonds. The purpose of this research was to investigate the effect of HTPB resin structure and the ratio of reactants used on the HTPB nitration process. For this purpose, four samples of nitrated Hydroxyl-terminated polybutadiene (Nitro-HTPB) were synthesized from two different types of HTPB with different characteristics and using two different proportions of the reactants. Then, samples were characterized by FT-IR and 1HNMR tests, and parameters such as percentage of nitration, microstructure, and their rheological behavior were compared. The results showed that the nitration rate of the synthetic samples was influenced by the ratio of the reactant used and the percentage of trans-microstructure of the initial HTPB resin. Also, samples with higher nitration content have higher viscosity and less pot life. Considering all the parameters, it can be claimed that NHA1 resin with 12.2% nitro content among synthesized resins (among 3.1, 4.1, 12.2, and 17.6%) has the potential to be used as a binder in energetic composites.

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References

[1] Zhou Y., Long X. P., Zeng Q. X., Simulation Studies of The Interfaces of Incompatible Glycidyl Azide Polymer/Hydroxyl‐Terminated Polybutadiene Blends by Dissipative Particle Dynamics. I. The Effect of Block Copolymers and Plasticizers, Journal of Applied Polymer Science, 125: 1530-1537 (2012).
[2] Cappello M., Lamia P., Mura C., Polacco G., Filippi S., Azidated Ether-Butadiene-Ether Block Copolymers as Binders for Solid Propellants, Journal of Energetic Materials, 34: 318-341 (2016).
[3] کبریت‌چی، عباس؛ قانع قره‌باغ، میلاد، پلیمرهای پرانرژی در پیشران‌ها: رزین پلی‌بوتادی‌ان با انتهای هیدروکسیل پرانرژی (EHTPB) آزیدی و متصل به فلز، مجله پژوهش و توسعه فناوری پلیمر ایران، (4)2: 17 تا  (1396).
[4] Shekhar Pant C., Santosh M.S., Banerjee S., Khanna P.K., Single Step Synthesis of Nitro‐Functionalized Hydroxyl‐Terminated Polybutadiene, Propellants Explosives Pyrotechnics, 38: 748-753 (2013).
[5] Colclough M.E., Paul N.C., Nitrated Hydroxy-Terminated Polybutadiene: Synthesis and Properties, ACS Publications, 623: 97-103 (1996).
[6] کبریت‌چی، عباس؛ قانع قره‌باغ، میلاد، بررسی انواع رزین پلی‌بوتادی‌ان با انتهای هیدروکسیل (HTPB) پرانرژی نیترات‌دار ‌شده و خواص پیشرانه جامد مرکب بر پایه آن، مجله پژوهش و توسعه فناوری پلیمر ایران، (2)2: 15 تا  (1396).
 [7]Abusaidi H., Ghorbani M., Ghaieni H.R., Development of Composite Solid Propellant Based on Nitro Functionalized Hydroxyl‐Terminated Polybutadiene, Propellants Explosives Pyrotechnics, 42: 671-675 (2017).
[8] Gayathri S., Reshmi S., Nitrato Functionalized Polymers for High Energy Propellants and Explosives: Recent Advances, Polymers for Advanced Technologies, 28: 1539-1550 (2017).
[9] قاینی، حمیدرضا؛ ابوسعیدی، هادی؛ معتمدالشریعتی، سیدهادی، بهینه سازی پارامترهای مؤثر بر سنتز Nitro-HTPB، نشریه علمی پژوهشی مواد پرانرژی، (2)10: 65 تا (۱۳۹۴).
[10] اشرفی، مهدی، سنتز و بررسی خواص نرم‌کننده پلیمری پرانرژی NPB  و مطالعه خواص عملکردی آن به همراه بایندر  NHTPB در فرمولاسیون مواد منفجره پلاستیکی، رساله دکتری شیمی آلی، دانشکده علوم پایه، دانشگاه جامع امام حسین (ع) (1395).
[11] Pavia D.L., Lampman G.M., Kriz G.S., Vyvyan J.A., "Introduction to Spectroscopy", Cengage Learning, United States of America (2008).
[12] Mahanta AK., Pathak DD., "HTPB-polyurethane: A Versatile Fuel Binder for Composite Solid Propellant", Polyurethane, Instrumentation Technology, India (2012).
[13] Sekkar V., Raunija TS., Issues Related with Pot Life Extension for Hydroxyl‐Terminated Polybutadiene‐Based Solid Propellant Binder System, Propellants Explosives Pyrotechnics, 40: 267-74 (2015).
[14] Sekkar V., Raunija TS., Hydroxyl-Terminated Polybutadiene-Based Polyurethane Networks as Solid Propellant Binder-State of the Art, Journal of Propulsion and Power, 31: 16-35 (2014).
[15] Mahanta A.K., Dharmsaktu I., Pattnayak PK., Rheological Behaviour of HTPB-Based Composite Propellant: Effect of Temperature and Pot Life on Casting Rate, Defence Science Journal, 57: 435-       (2007).
[16] Vesna R., Petric M., The Effect of Curing Agents on Solid Composite Rocket Propellant Characteristics, Scientific Technical Review, 4: 46-50 (2005).
[17] Sekkar V., Ambika Devi K., Ninan KN., Rheo‐Kinetic Evaluation on the Formation of Urethane Networks Based on Hydroxyl‐Terminated Polybutadiene, Journal of Applied Polymer Science, 79, 1869-1876 (2001).
[18] Sekkar V., Venkatachalam S., Ninan KN., Rheokinetic Studies on the Formation of Urethane Networks Based on Hydroxyl Terminated Polybutadiene, European Polymer Journal, 38: 169-78 (2002).

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