The effects of henna fillers on the properties of polyurethane foam composites

Polyurethane (PU) foam were produced from polyol (PolyGreen R3110) and 4,4-diphenylmethane diisocyanate (Maskiminate 80) with distilled water as a blowing agent. Natural fibers have received more attention from researchers due to their ability to increase the properties of the polymer composites. In this work, PU/Henna foam composites were prepared by used Henna fibers at different loading of 5, 10, 15 and 20 wt. %. The effect of different Henna loading on PU foam were investigated by density, compression test, morphology and water absorption. Core density of PU/Henna foam composites increased with addition Henna compared to control PU and showed highest core density of 85.10 kgm-3 . Compressive strength decreased to 0.53 MPa after Henna addition at 5 % PU/Henna foam composites. Henna addition to 20 % PU/Henna foam composites were reduced the compressive strength to 0.97 MPa due to stiffness effect of Henna that contributed to embrittlement of the cell wall. The distorted cell wall and less uniform of cell structure were proved by SEM due to Henna addition as compared to control PU. Water absorption percentage of PU/Henna foam composites were increased with Henna addition as compared to control PU. It is because hydrophilic properties of Henna tendency to absorb moisture.