3.1.4. Structural Properties

Microscopic analyses were performed on lab-scale pellets to evaluate the distribution of fibers in the matrix. Figure 5 shows the fractions 0.3–0.85 mm (a) and 0.15–0.3 mm (b) of the straw powders at the magnification of 50×. Particles appear as straight rods with diameters about 0.1–0.2 mm (fraction 0.3–0.85 mm) and as irregular needles with the presence of rectangular pieces in the fraction at lower dimensions (b). In both figures the presence of silica is clearly shown by the light reflection on the surface of the samples.

**Figure 5.** Fraction 0.3–0.85 mm (**a**) and 0.15–0.3 mm (**b**) of the straw powders at the magnification of 50× at optical microscope.

### *3.2. Commercial Rice Straw and Rice Husk Pellets*

After the confirmation of the suitability of RS for palletization without the use of any binder, commercial pellets were produced as described in Section 2.2. Afterwards, their main properties were evaluated.
