The effect of beetroot peel fibers particle size on physical, mechanical and structural properties of the natural composite

Beetroot peels (BR) fibers have been employed as a natural reinforcement for Unsaturated Polyester (UPE) due to their low cost, biodegradability characteristics and eco-friendliness. Beetroot peels particulates of about (180 and 75 µm) sieve siz, of different weight percentage (1, 2, 3, 4 and 5 wt.% %) were used as fillers in a (UPE) matrix. The effects of the beetroot particle size on physical, mechanical and structural properties of the final natural composite were determined. The density of (UPE/ 180 MBR) composite increases by increasing weight percentage of beetroot peels powder, but the density of (UPE/ 75 MBR) decreases by increasing weight percentage of beetroot peels powder. The thermal conductivity values of (UPE/ 180 MBR) composites have higher values, by compared with the thermal conductivity values of (UPE/ 75 MBR) composites. The results showed that the best mechanical properties were get by adding (2 Wt.%) to the (UPE)matrix using (180 MBR) and at (4 Wt.%) by adding the (75 MBR). The techniques (EDS) and (SEM) were used to investigate the chemical compositions and the homogeneity degree of both composites.