Bio-Polyethylene Composites Based on Sugar Cane and Curaua Fiber: An Experimental Study

For the purpose of renewable materials applications, Curaua fiber treated with 5% sodium hydroxide was added to high-density biopolyethylene, using an entirely Brazilian raw material of sugarcane ethanol. Polyethylene grafted with maleic anhydride was used as a compatibilizer. With the addition of curaua fiber, the crystallinity was reduced, possibly due to interactions in the crystalline matrix. A positive thermal resistance effect was observed for the maximum degradation temperatures of the biocomposites. When curaua fiber was added (5% by weight), the morphology showed interfacial adhesion, greater energy storage and damping capacity. Although curaua fiber additions did not affect the yield strength of high-density bio polyethylene, its fracture toughness improved. With the addition of curaua fiber (5% by weight), the fracture strain was greatly reduced to about 52%, the impact strength was also reduced, suggesting a reinforcing effect. Concomitantly, the modulus and the maximum bending stress, as well as the Shore D hardness of the curaua fiber biocomposites (at 3 and 5% by weight), were improved. Two important aspects of product viability were achieved. First, there was no change in processability and, second, with the addition of small amounts of curaua fiber, there was a gain in the specific properties of the biopolymer. The resulting synergies can help ensure more sustainable and environmentally friendly manufacturing of automotive products.