Nano-dimension pore structure analysis of poly(ethylene terephthalate) knitted materials: An insight combining SEM images

Scanning Electron Microscopy (SEM), an easily acquired and widely applied image acquisition and analysis method, have rarely been used to study the pore structure of poly(ethylene terephthalate) knitted fabrics after ultraviolet irradiation simultaneously ozone gas exposure. In this work, we present an investigation of nano-dimension detection of the pores and fractures using SEM observations. The morphological characteristics of the poly(ethylene terephthalate) fabric surface can be revealed by SEM method. By detecting 9 high resolution SEM images, the pores morphology of different scales were acquired. And the studied poly(ethylene terephthalate) knitted substrate shows different types of pores and holes with multi-resolution at the surface layer after ultraviolet irradiation and ozone gas exposure for 80 minutes. This work demonstrated that the combination of two dimensional (2D) SEM results is effective in detection of surface morphology, and is of significance in revealing the pore structure of materials at nano dimension scale. Sub-micron porosity with pore radii as small as 2.5–10 nm was observed in SEM cross-sections. The formation of nano dimensional pores on the surface of the fabric is because of the physical etching ( due to the ion bombardment in the radiation chamber).