Htpb
Mostrando 1-12 de 32 artigos, teses e dissertações.
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1. Evaluation of Filler Effects on the Dynamic Mechanical Behavior of HTPB-Elastomer Used as Binder in Exemplary Composite Formulations
ABSTRACT: This study aims to evaluate the dynamic mechanical properties of a binder, used in composite propellants, with increasing amount of different solid fillers. Dynamic Mechanical Analysis (DMA) is performed to determine the region of glass-rubber transition temperature (Tg). Further parameters were obtained from the description of the loss factor curv
J. Aerosp. Technol. Manag.. Publicado em: 2017-09
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2. Slow Cook-Off Simulation of PBX Based on RDX
ABSTRACT: Cook-off tests are commonly used to assess thermal behaviour of energetic materials under external thermal stimuli. Numerical simulation became a powerful tool to reduce the costs with experimental tests. However, numerical simulations are not able to predict the violence of thermal response, but instead accurately reproduce radial heat flow in the
J. Aerosp. Technol. Manag.. Publicado em: 2017-06
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3. Cloisite 15Aº nanoclay as an effective PTC for the epoxidation of hydroxyl terminated polybutadiene (HTPB)
A simple method is reported for the epoxidation of hydroxyl-terminated polybutadiene (HTPB) by using in-situ generated dimethyl dioxirane (DMD) as an oxidant and Cloisite 15Aº nanoclay as a phase-transfer catalyst (PTC). In order to find the optimum reaction conditions, real time analyses of the products as well as epoxidation progress, followed by ¹HNMR a
Polímeros. Publicado em: 12/09/2014
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4. Desenvolvimento de tecnologia de pré-polímeros na síntese de poliuretanos empregados em combustíveis sólidos
The aim of this work was to synthesize a polyurethane polymer matrix using polyols as a raw material to obtain a binder such as the hydroxyl terminated polybutadiene (HTPB) pre-polymer in energetic material formulation. The soybean-based polyol was the best starting raw material for producing a binder for solid fuel formulation in rocket motor applications.
Quím. Nova. Publicado em: 2014-07
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5. Acúmulo de cargas elétricas em propelente sólido compósito com matriz de polibutadieno líquido hidroxilado
Composite solid propellants prepared with HTPB prepolymer - Hydroxyl Terminated Polybutadiene, AP - Ammonium Perchlorate as oxidizer and aluminum particles as an additive metal, have characteristics of high electrical resistivity. The loading process of the polymer matrix did not obtain homogeneity, resulting in clusters, mainly of metal particles. The effec
Quím. Nova. Publicado em: 2014
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6. Effect of hyperbranched polyesters on HTPB polyurethane curing kinetic
Effects of hyperbranched polyesters on kinetics of the reaction between hydroxyl-terminated polybutadiene (HTPB) and isophorone diisocyanate (IPDI) were investigated. HTPB and IPDI were in-situ cured in the presence of two different hyperbranched polyesters, stearic acid ester-terminated hyperbranched polyester (SHPE) and acetate-terminated hyperbranched pol
Mat. Res.. Publicado em: 03/12/2013
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7. An Overview of the Technological Progress in Propellants Using Hydroxyl-Terminated Polybutadiene as Binder During 2002-2012
ABSTRACT: The purpose of this article is to present a study on the technological development of propellants, which are used in solid and hybrid rocket motor, that have been employing hydroxyl-terminated polybutadiene (HTPB) as a binder, for the past ten years. The results prove that major research conducted on propulsion technologies continues using HTPB as
J. Aerosp. Technol. Manag.. Publicado em: 2013-09
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8. Síntese de poliuretanos modificados por óleo de mamona empregados em materiais energéticos
The aim of this work was to synthesize a polyurethane polymer matrix using castor oil as a polymer chain modifier, whose characteristics can be adjusted for use as a binder in the manufacture of energetic materials such as propellant and pyrotechnics for aerospace use. We attempted the partial substitution of hydroxyl-terminated polybutadiene (HTPB), a pre-p
Quím. Nova. Publicado em: 2013
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9. Thermal aging of HTPB/IPDI-based polyurethane as a function of NCO/OH ratio
Thermal aging of hydroxy-terminated polybutadiene/isophorone diisocyanate (HTPB/IPDI)-based polyurethane was studied as a function of NCO/OH ratio (1.0 and 0.85). Samples were aged in air ovens at 50, 60, 65, and 70 ºC for periods of time from 1 to 34 weeks. Changes in chemical (swelling testing and FT-IR spectroscopy) and mechanical (tension testing and ha
Materials Research. Publicado em: 16/09/2011
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10. Síntese e caracterização de nanocompósitos à base de poliuretano dispersos em água com argilas hidrofílica e organofílica / Synthesis and characterization of nanocomposites based on polyurethanes dispersed in water with hydrophilic and organophilic clays
A área de pesquisa de materiais nanoestruturados tem recebido destacada atenção nos últimos anos por parte da comunidade científica, ressaltando-se os nanocompósitos à base de polímero e argila. Nesta Dissertação foram sintetizados nanocompósitos à base de poliuretano (NWPUs) com argilas do tipo montmorilonita (MMT), hidrofóbicas (organofílicas
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 05/07/2010
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11. Performance evaluation of commercial copper chromites as burning rate catalyst for solid propellants
Abstract: Copper chromites are well known as burning rate catalysts for the combustion of composite solid propellants, used as a source of energy for rocket propulsion. The propellant burning rate depends upon the catalyst characteristics such as chemical composition and specific surface area. In this work, copper chromite samples from different suppliers we
J. Aerosp. Technol. Manag.. Publicado em: 2010-12
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12. Diffusion of plasticizer in a solid propellant based on hydroxyl-terminated polybutadiene
The aim of this work was to determine the dioctyl azelate (DOZ) plasticizer diffusion coefficient (D) for samples containing the interfaces of rubber, liner and solid composite propellant based on hydroxyl-terminated polybutadiene (HTPB). The samples used in the diffusion study were aged up to 31 days after the cure period at 80 °C. A computer program imple
Polímeros. Publicado em: 12/11/2010