Then the cut surfaces were smoothed under liquid nitrogen in a standard way [3, 5], The blends containing 90-60 wt% of HDPE were etched for 5 min with toluene at room temperature, while the samples with 50-10 wt% of HDPE were etched for 4 min with a
permanganic mixture as described elsewhere [3, 20].
Before observing with a scanning electron microscope instrument (FEI-1NSPECT F, USA) at an acceleration voltage of 20 kV, the samples were etched by
permanganic etching technique, and then the surface were washed, dried, and covered with a thin layer of gold.
Subsequently, the specimens were etched following the
permanganic etching technique developed by 011ey and Bassett [18], After the specimens were coated with gold, their fractured surfaces were examined using a scanning electron microscope (SEM, FEI Nova NanoSEM 430) at an accelerating voltage of 5 kV.
The specimens with smooth surfaces were removed from liquid nitrogen and etched with a
permanganic mixture (PP is etched) or toluene (PS is etched).
Before our observation, the SEM samples were cut from the pipes and put into the 50 [degrees]C
permanganic etchant for 3 h to remove the amorphous phase.
The exposed surface was etched with
permanganic reagent [32] for 1 h at room temperature.
The smooth surfaces were etched for 2 min with a
permanganic mixture (0.7 g KMn[O.sub.4] in 10 ml of conc.
The microtomed films were then etched for 20 minutes with
permanganic acid and coated with platinum prior to observation.
The samples were etched using the
permanganic acid etching procedure described in Ref.
Similarly, Olley et al., working with consolidated UHMWPE hip cups, confirmed that after
permanganic etching, the fusion defects/particle boundaries can be observed (15).
1]: samples were polished, then immersed at room temperature in a
permanganic acid solution which preferentially etches the amorphous part of the polymer [19, 20], and finally washed with different solutions.
Both specimens (one is fractured after tensile test and the other microtomed cutting at -100[degrees]C, etched by
permanganic acid, washed with hydrogen peroxide and distilled water) were coated with gold, which is a high conducting material to prevent local charging from the scanning electron beam.