Nanocrystalline Cellulose from Kapok Fiber (Ceiba pentandra) and its Reinforcement Effect on Alginate Hydrogel Bead

Kapok fiber (Ceiba pentandra) is a potential source of cellulose, but its utilization is still minimal. This study aims to isolate nanocrystalline cellulose (NCC) from kapok fibers using acid hydrolysis at various times and characterize its properties as reinforcement for alginate-nanocrystalline cellulose (Alg-NCC) hydrogel beads. NCCs are characterized using various techniques, and hydrogel beads are characterized by syneresis and strength (TPA). Variations in hydrolysis time cause changes in functional groups, decrease length and diameter, increase degree of crystallinity, and thermal stability. Nanocrystalline cellulose isolation from BKF by chemical hydrolysis is better done at 60% sulfuric acid concentration, for 50 min to produce a yield of 38.92%, L/d aspect ratio ranges from 8.53 to 12.23, degree of crystallinity 71.00%, and thermal stability with maximum degradation temperature 298.69 °C. The incorporation of NCC on the Alg hydrogel beads leads to increase hardness 67.70% and decrease syneresis 4.14%. Thus, NCC can be used as a reinforcement agent because it has been shown to improve the physical, mechanical, and thermal properties of Alg-NCC hydrogel beads. Alg-NCC hydrogel beads have the potential to be widely applied in various fields.