Dynamic studies of polypropylene nonwovens in environmental scanning electron microscope

Environmental scanning electron microscopy (ESEM) provides new tools to examine the dynamic behaviour of various materials under different conditions. The dynamic experiments of water wetting, oil sorption and loading deformation of polypropylene (PP) nonwovens in the ESEM were studied in this paper. Water wetting tests were performed by controlling the temperature of the specimens and chamber pressure in favour of water condensation at 100% relative humidity. The wetting by oil was made using a micro-injector to add oil droplets onto specimens being observed. The ESEM observations revealed the contrast in the wetting behaviour of the PP nonwovens towards water and oil. Tensile testing experiments were performed in the ESEM using a tensile stage. The dynamic studies gave new insight into microscopic behaviour of PP nonwovens.