Mechanical properties of HTPB-IPDI-based elastomers

Haska, SB
Bayramli, E
Pekel, F
Özkar, Saim
A polyurethane elastomer having mechanical and adhesive properties suitable for liner applications in solid rocket propellants was developed using HTPB as the prepolymer and IPDI as the curing agent. The effects of the NCO/OH ratio (R value) and the triol/diol ratio on the mechanical properties of the polyurethane matrix were investigated. The reaction of HTPB and IPDI is followed by monitoring the changes in the IR absorption bands of the NCO stretching at 2255 cm(-1) and the CO stretching at 1730 cm(-1). It was found that the rate of the polyurethane formation obeys an overall second-order kinetics. At an R value of 1.15, the elastomer shows the maximum tensile strength and 200% elongation at break. The hardness, elongation, and the tensile strength reach a steady value around the same R value. The elastomers having a triol/diol ratio less than 0.03 show a decrease in the tensile strength and modulus with a concomitant increase in elongation. At a triol/diol ratio greater than 0.05, the tensile strength increases to about the same value for the liner composition without any triol component. The elongation reaches a steady level at a triol/diol ratio of 0.10 and one observes a steady increase in hardness up to about 0.5. The modulus for the compositions having a triol/diol ratio greater than 0.1 is about 50% higher than that for the composition without triol. (C) 1997 John Wiley & Sons, Inc.


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Aslan, Onurcan; Özkan, Necati; Yılmaz, Gürkan Atınç; Department of Polymer Science and Technology (2021-2-11)
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Erten, Emre; Kaynak, Cevdet; Atalar, Taner; Department of Metallurgical and Materials Engineering (2022-8)
Hydroxyl-Terminated-Polybutadiene Polyurethane (HTPB-PU) elastomer materials are mainly used in the “liner” layer of solid propellant rocket motor cases. The required levels of mechanical and thermal properties are obtained by reinforcing this elastomer matrix with approximately 10 wt% micron-sized carbon black (mCB) particles. Therefore, the main purpose of this study was to investigate effects of mCB alone and then when used together with 3 wt% nano-sized carbon black (nCB), micron-sized zirconia (mZrO2),...
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Nano patterning of AISI 316L stainless steel with Nonlinear Laser Lithography: Sliding under dry and oil-lubricated conditions
Gnilitskyi, Iaroslav; Rotundo, Fabio; Martini, Carla; Pavlov, Ihor; Ilday, Serim; Vovk, Evgeny; Ilday, Fatih Omer; Orazi, Leonardo (2016-07-01)
Femtosecond laser-based Nonlinear Laser Lithography (NLL) was applied to AISI 316L stainless steel, which requires surface modification to achieve satisfactory tribological behaviour. NLL advances over the well-known Laser Induced Periodic Surface Structures (LIPSS) in terms of uniformity and long-range order of high speeds, over large areas. A galvanometric scanner head was used for an high production rate. Dry and lubricated sliding tests, considering different orientations of the nanotexture showed that ...
Citation Formats
S. Haska, E. Bayramli, F. Pekel, and S. Özkar, “Mechanical properties of HTPB-IPDI-based elastomers,” JOURNAL OF APPLIED POLYMER SCIENCE, pp. 2347–2354, 1997, Accessed: 00, 2020. [Online]. Available: