Mechanical property degradation and structural failure of flexible laminated composite envelope upon exposure to high-altitude atmosphere

The mechanical performance and structural evolution of a flexible laminated composite envelope material after 5 years of service were investigated by uniaxial tensile test and interfacial peeling test. Compared with a pristine material, the post-utilized envelope material degraded severely in the aspects of surface appearance, intrinsic structure, and tensile strength owing to the erosion caused by a harsh environment. To determine the structural aging and mechanical property deterioration mechanism, wide-angle X-ray diffraction and attenuated total reflection Fourier transform infrared were performed on specific structural components of the envelope material. The structural causes of mechanical property degradation of the post-utilized envelope material are discussed in this paper in consideration of the coupling effects of multiple environmental factors (environmental load and radiation).