A comprehensive characterization of chemically treated Brazilian sponge-gourds (Luffa cylindrica)

Sponge-gourds, the fruit of Luffa cylindrica, are widely used throughout the world. Despite that, there is lack of scientific data concerning thermal, mechanical, and chemical properties of these fibers. Sponge-gourds biocomposites are a novel use of these fibers, but a better understanding of their surface characteristics is necessary to maximize their potential use. In this work, different chemical treatments were conducted on the fibers with aqueous solutions of NaOH 2%, or methacrylamide (1-3%) at distinct treatment times. L. cylindrica was characterized via chemical analysis and analytic techniques such as FTIR, XPS/ESCA, X-Ray, TGA and SEM. Methacrylamide 3% treatment for all times (60, 120 or 180 min) severely damaged the fibers. NaOH, on the other hand, showed the same beneficial effect regarding enhancement of surface area and thermal stability together with similar levels of lignin and hemicellulose extraction, without causing exaggerated harm to fiber integrity.