Nano filled polybenzimidazole (PBI) film coating for improved environmental performance in space

Abstract

The spacecraft in the low earth orbit (LEO) is influenced by many parameters like Atomic oxygen, High Vacuum, thermal cycling, Ultraviolet radiation and MMOD impacts. It is essential to study the response of the material in these conditions because they have a degradatory effect on the material. This paper discusses about an approach to improve the structural performance of the composite structure (CFRP) for space applications using carbon nanotube (CNT) as a filler in a Polybenzimidazole (PBI) film coated on the composite structure. A 2 wt% CNT/PBI film was coated mechanically and cured in a vacuum oven. The PBI/CFRP and the CNT-PBI/CFRP coated samples were studied for LEO environment test for effective radiation shielding and hypervelocity impact test for energy absorption. The use of CNTs in the PBI coating improved the shielding performance in LEO by 35.21%. SEM analysis also showed that the surface cracks decreases with the introduction of CNTs. However, there was no significant improvement noticed in the hypervelocity impact tests for a similar value of film thickness.