Effect of Fiber Pre-treatment Methods on Hygrothermal Aging Behavior of Agave Fiber Reinforced Polymer Composites

Three different pre-treatment methods, that is, alkali hornification, water hornification, and alkali treatment, are evaluated for the improvement in durability of agave natural fiber-reinforced polymer composites under the hygrothermal aging conditions. The composite specimens were prepared following the standard test procedures laid for moisture diffusion analysis. To analyze the effect of different treatment conditions, the standard test specimens were subjected to different hygrothermal aging conditions in the accelerated environments. After four subsequent hornification cycles, the alkali hornification resulted in about 27% lower water retention value in the agave fibers. Under similar conditions, water hornification leads to a meager 6% loss of water retention. Under the direct exposure to water, the alkali-hornified composites had a mass gain of 4.1%, 4.3%, and 4.7%, respectively, at 25 degrees C, 50 degrees C, and 75 degrees C. The mass gain of alkali-treated composites was 4.3%, 4.5%, and 5.1%. and water hornification resulted in a mass gain of 5.5%, 5.9%, and 6.1% at similar temperatures. Under the humidity conditions, the alkali-hornified composites had a mass gain of 0.9%, 1.3%, and 1.1%, respectively, at 25 degrees C, 50 degrees C, and 75 degrees C. The mass gain of alkali-treated composites was 0.6%, 1.05%, and 1.2%. and water hornification resulted in the mass gain of 0.66%, 1.07%, and 1.3% at similar temperatures. The present study reveals the influence of fiber pre-treatment methods on moisture durability of agave natural fiber composites. The results are further supported through microstructural investigations.