*2.2.2. Particle size distribution of fillers*

To evaluate the particle size distribution, fillers were classified after grinding (for rice husk) by screening into four mesh size ranges 20–35, 35–45, 45–80, and >80 per inch (approximately 500–850, 350–500, 180–350 μm, and <180 μm). The filler particles were then weighed in order to determine the weight of the fillers in each mesh size range.
