Preliminary results of DOA plasticizer effect on AP/HTPB composite propellant characteristics
Anita Pinalia, Bayu Prianto, H. Setyaningsih
Abstract
AP/HTPB composite propellant is a type of rocket fuel that is still widely used for both defense rockets and civilian rockets in space technology. As a fuel, the propellant needs to have properties or characteristics that meet fuel standards. Some substances in minor quantities are often added to solid propellants as an additive to improve the propellant characteristics. The plasticizer is used as an additive to increase the flexibility, softness, and workability of the propellant. This agent is responsible for the reduction in tensile strength and elastic modulus of the material. In this work, the physical and mechanical properties of propellants from various compositions were tested to see the effect of DOA plasticizer on propellant characteristics. The results indicate that the viscosity and hardness decrease as the percentage of DOA increases, but it has no significant effect on density. In mechanical properties, modulus decrease with increasing DOA. In this study, increasing DOA with a significant ratio between moles of di-ester in DOA and moles of OH in HTPB led to an increase in the elongation value but a decrease in the tensile strength. On the other hand, increasing DOA with an insignificant ratio gave the opposite result in the elongation value. The optimum DOA is closely related to the DOA diester mole value which approached the OH mole value in HTPB. in this work the optimum percentage of DOA is 2.25%.