Moisture Absorption Characteristics and Subsequent Mechanical Property Loss of Enset–PLA Composites

Abstract

One of the drawbacks of natural fibers and their composites is their inherent hydrophilic nature. The effect of moisture on the mechanical properties of composites is irrefutable. This study deals with the hygroscopic characteristics of enset–PLA composites and their effect on the mechanical properties of the composites. To do this, injection-molded composite specimens with different fiber volume fractions, plasticizer ratios, fiber lengths, and fiber ages were considered. The specimens were exposed to distilled water, and the moisture absorption was monitored on a daily basis. Subsequently, the specimens were subjected to mechanical loading to determine the effect of moisture on their strength, stiffness, and strain at break strength. Lastly, the individual and joint effects of the considered factors were scrutinized using an optimal experimental design. The results of the study show that the maximum and minimum moisture uptakes were recorded for 25% and 15% fiber ratios, respectively. Due to the effect of moisture, the tensile and bending strength decreased by 11% and 5%, respectively, for the 15% fiber volume fraction and decreased by 16% and 13%, respectively, for the 25% fiber volume fraction. Increasing the amount of plasticizer increases the moisture resistance. The results indicate that Enset–PLA composites have competitive properties and stability when exposed to moisture.