Mapping of optimized responses in polyurethanic matrix based on HTPB of commercial grade for application in solid propulsion rocket motors

• Grant number: 18/06447-0
• Support Opportunities: Scholarships in Brazil - Master
• Start date: July 01, 2018
• End date: July 31, 2020
• Field of knowledge: Engineering - Aerospace Engineering
• Agreement: Coordination of Improvement of Higher Education Personnel (CAPES)
• Principal Investigator: Elizabete Yoshie Kawachi
• Grantee: Renata Fraga Cardoso
• Host Institution: Divisão de Ciências Fundamentais (IEF). Instituto Tecnológico de Aeronáutica (ITA). Ministério da Defesa (Brasil). São José dos Campos , SP, Brazil

Abstract

The main purpose of the composite propellant is to provide propulsive energy to solid rocket motors. Composite propellant is constituted by a continuous phase named as polymeric matrix, and a non-continuous phase, known as solid loading. It is necessary that the propellant presents enough structural resistance to support the efforts that the engine is submitted during its life cycle. Polyurethanic systems based on hydroxyl-terminated polybutadiene (HTPB) are the most common matrixes used on formulation of composite propellants due to their microstructure characteristics, which provides the mechanical, physico-chemical, and thermal requirements for the composite propellants. There are two homopolymers of HTPB commercially available, for which the main difference is the hydroxyl content. One of the HTPB has exclusive use in propellant formulation, and it is historically named as HTPB military grade. The other HTPB is applied in the industry of elastomers, and is known as HTPB commercial grade. The aim of this project relies on mapping the experimental conditions that allow the use of HTPB commercial grade in the formulation of propellant matrix for optimization of mechanical, physico-chemical, and thermal proprieties, through the use of factorial experimental design and multi-response optimization techniques. The development of this project is vitally important for the maintenance and development of new projects of new orbital and suborbital vehicles with less dependence on imported inputs, since some of them suffers from embargoes, such as HTPB military grade. (AU)