Characterization of a new natural cellulose fiber from Enhalus acoroides and its potential application

Abstract

Enhalus acoroides (L.f.) Royle is a tropical seagrass species that contains large amounts of cellulose and hemicellulose. During monsoons, leaves of this species wash up along beaches, accumulate and decompose anoxically, causing unpleasant odors. This leaf waste could be exploited by extracting the cellulose fibers. Prepared leaf waste was alkaline-treated and bleached. At each stage of treatment, the properties of the fiber were characterized by color spectrophotometry, scanning electron microscopy (SEM), thermogravimetric analysis (TGA), Fourier transform infrared (FTIR) spectrometry, and X-ray diffractometry (XRD). The diameter of the untreated fiber was 66.67 µm. After alkaline treatment, the diameter was 8.30 µm. Bleaching with hydrogen peroxide decomposed the alkaline-treated fiber into individual microfibrils with a diameter of 6.67 µm. The bleached microfibrils had a high whiteness value of L*= 92.47, and high degrees of thermal stability (Tmax 363 °C) and crystallinity (59%). The properties of the bleached microfibrils were appropriate for the reinforcement of a polymer composite. Therefore, using compression molding, we produced a biodegradable seeding pot prototype from a thermoplastic starch (TPS) reinforced with 5 wt% of bleached fiber from E. acoroides (L.f.) Royle.