Studies of high-performance fabric-based laminated hull material for stratospheric airship

Abstract

In terms of communications and scientific observations, a stratospheric airship can be an effective alternative to the artificial satellites in Earth’s orbit. For an airship to float in the low air-density stratosphere, it must be designed with light, flexible, and strong materials. In the present study, we have designed and developed six different coated and laminated structures by using high-performance para-aramid fabric, polyvinylidene chloride (PVDC)-coated biaxially oriented polyethylene terephthalate (BOPET), and polyvinyl fluoride (PVF) films. The developed coated and laminated stratospheric airship structures demonstrate excellent performance even in the harsh environmental conditions such as very low atmospheric pressure (∼0.001 atm), extreme temperatures (80°C in the day and −80°C in the night;), high UV irradiation, and ozone as well as atomic oxygen. In order to analyze the effect of the harsh environmental conditions existing in stratospheric atmosphere on physico-mechanical properties such as tensile strength, tear strength, peel strength, and helium (He) gas barrier of the prepared laminate structures, they were evaluated after exposure in simulated accelerated artificial weathering conditions up to 400 h. The developed multilayered laminated structures exhibited superior He-gas permeability (0.04 L/m2/24 h), high tensile strength (>820 N/cm), and good tear strength (401–477 N/cm) with relatively low areal density (207–262 g/m2). Furthermore, all the laminates also demonstrated very low degradation in mechanical properties, that is, 3%–8% in peel strength, 1%–3% in tear strength, and 1%–2% in tensile strength under artificial weathering conditions up to 400 h.