Modeling the mechanical behavior of epoxy Curaua reinforced composites

In recent decades, it has become essential to find and develop materials from non-petroleum sources that are more compatible with nature. The present work describes the mechanical properties of a composite with epoxy matrix reinforced with natural Curaua fibers. To improve the matrix-fiber interaction, the Curaua fibers were immersed in solutions with different concentrations of sodium hydroxide (NaOH) for different treatment times. After washing, they were mixed in epoxy and specimens were cut for use in tensile, flexural, and dynamic mechanical analysis tests. The results were compared to untreated fibers, showing improvement of maximum tensile strength up to 30% and 10% for maximum flexural strength. For this test, the flexural modulus improved by 12%. On the other hand, Young’s modulus did not change as much. This can be associated with degradation of the fibers when immersed for many hours in a high concentration of NaOH. In the conclusion, this topic is analyzed as a factor of how the alkaline solution can affect the fiber surface.