Synthesis of Cellulose Beads from Wastepaper via the Microemulsion and Precipitation Method
摘要
Synthesis parameters such as cellulose (1–5% w/v) and surfactant (0–6% w/v) concentrations are investigated and optimized on controlling the mean diameter of cellulose beads. Cellulose fibers from printed paper wastes are extracted and used to prepare cellulose beads via a water-in-oil (W/O) microemulsion and precipitation techniques. Different cellulose solutions of concentrations were prepared by dissolving cellulose fibers in NTU solvent (NaOH: thiourea, urea, 8:6.5:8% w/v). Cellulose beads were precipitated out by dilute acetic acid solution. Under FESEM, it was observed that smaller cellulose beads (≤ 1 µm) were formed with and without surfactant, which in this case, Span 80 (Sorbitan monooleate). Spherical beads with porous surfaces were shown when surfactant concentration increased. The smallest mean diameter was 0.166 µm at 1% w/v cellulose concentration without Span 80, while the largest mean diameter of 1.153 µm obtained from 5% w/v cellulose concentration and 6% w/v Span 80 concentration. Hence, small size cellulose beads of high specific surface area, low-cost and environmentally friendly are potentially useful as control release carriers.