Figure 1. Digital photographs demonstrate the gradient porosity changing from bottom to top side for both thermoset and pyrolyzed sample.

In the top, photos show white colored thermoset (cured) samples while in the photos given below pyrolyzed, so called “black glass”, samples can be seen. Photos were taken; (a) from the bottom side of the cured thermoset; (b) from the upper side of the cured thermoset; (c) from the bottom side of the pyrolyzed; and (d) from the upper side of the pyrolyzed sample.