[P008] Poster

1:00 PM - 1:50 PM JST(4:00 AM - 4:50 AM UTC)

[P04-584] Macroalgae-Derived Cellulose and Its Physicochemical Characterization for Application as a Reinforcing Material in Biodegradable Films

○Hari Eko Irianto¹, Nurhayati Nurhayati¹, Ellya Sinurat¹, Sosaku Ichikawa² (1. National Research and Innovation Agency (Indonesia), 2. University of Tsukuba (Japan))

Keywords:

Seaweed cellulose,Gracilaria sp.,Gelidium sp.,Ulva lactuca,microfibrillated cellulose (MFC),alkaline hydrolysis,acid hydrolysis,crystallinity,biodegradable film

The optimization of seaweed-based biopolymers is essential for developing sustainable alternatives to synthetic plastics. This study integrates findings on the extraction and characterization of cellulose and microfibrillar cellulose (MFC) from Indonesian macroalgae specifically Gracilaria sp., Gelidium sp., and Ulva lactuca - and evaluates their functional application in biodegradable films. The extraction process across these species involved alkaline hydrolysis and bleaching, with specific focus on acid types and alkali concentrations. For Gelidium sp., hydrolysis using sulfuric acid (H2SO4) yielded superior thermal stability (Tonset 311°C) and the highest crystallinity index (CrI) compared to HCl and HTFA (trifluoroacetic acid). In Ulva lactuca, a 30% NaOH concentration was identified as optimal, while higher concentrations led to structural degradation. Characterization via FTIR, XRD, and FE-SEM across all species confirmed the successful removal of hemicellulose and lignin, with Gracilaria-derived MFC achieving a significantly high CrI of up to 89% following ultrasonication. The application phase focused on enhancing corn starch-based biodegradable films using Gracilaria sp. cellulose. A completely randomized design (CRD) using concentrations of 010% (w/w) demonstrated that higher cellulose loading significantly improved the film’s mechanical properties, reaching a tensile strength of 25.8 MPa. Furthermore, while low-cellulose films degraded rapidly within seven days, those with 10% cellulose maintained better structural integrity and lower water vapor transmission rates. Overall, these findings highlight that the source of macroalgae and the specific chemical treatments particularly H2SO4 hydrolysis and 30% NaOH delignification are critical in determining the quality of the resulting cellulose. The study concludes that seaweed-derived cellulose serves as a high-performance reinforcing agent, offering a robust pathway for the production of sustainable, industrial-grade biodegradable packaging.