Highly Efficient Removal of Rhodamine B Dye Using Nanocomposites Made from Cotton Seed Oil-Based Polyurethane and Silylated Nanocellulose

Biobased polyurethane nanocellulose nanocomposites were synthesized from cottonseed oil as the source for the biopolyol. The prepared composites were used to study the adsorption of Rhodamine B dye from water. Low functional polyol was derived from cottonseed oil using one-pot synthesis method. Nanocellulose was derived from pineapple leaves and then it was surface-functionalized via silylation. In-situ polymerization technique was used to incorporate the silylated nanocellulose into the polyurethane matrix. The prepared polyol from cottonseed oil was found to have an OH functionality of 2 which was confirmed by Fourier transform infrared spectroscopy (FT-IR) and Nuclear magnetic resonance (NMR) spectroscopy. Low functionality of polyol is the key factor in achieving flexible porous polyurethane. The silylated nanocellulose, polyurethane, and composites were characterized by FT-IR, X-ray diffraction analysis (XRD), and Scanning electron microscopy (SEM). The adsorption parameters were optimized using the Taguchi methodology and the adsorption efficiency was determined by carrying out adsorption at optimized parameters (5 wt% loading of silylated nanocellulose, pH 9, and temperature of 30 °C) for 8 h. Studies showed that the prepared composite has a high adsorption efficiency of 597 mg/g of silylated nanocellulose towards Rh-B.