Spectroscopic Characterization of Acetylated Wood Flakes and Its High-Density Polyethylene Blends

Abstract

Yakubu Azeh^*, Fatima Abubakar, Monday Musah, John Tsado Mathew, Musa Tanko Umar, Yahaya Sayyadi Mohammad, Aliyu Turaki Ibrahim, Abdulkarim Mohammed Awwal, Hauwa Larai Muhammad Idris, and Aishetu Ibrahim Muhammad

Acetylation is a useful reaction for the improvement of the surface properties of natural fibers in bend/composites fabrications, which are essential in the determination of their usefulness.  In this study, the effects of acetylation on wood flakes/fibers of Gmelina Arborea was investigated. Acetylation was carried out in batches using acetic anhydride as an acetylating agent and acetic acid as a catalyst at 120˚C for 1, 2, and 3 h under reflux. The efficiency of acetylation was evaluated in terms of weight percent gains (WPGs) due to acetylation. Polyethylene blends were prepared by the solution blending of acetylated/unacetylated wood flakes using casting-evaporation method in toluene. The effects of acetylated/unacetylated wood flakes on the biodegradability of blends were investigated. Acetylated wood and blends were characterized using Fourier transform infrared spectroscopy (FT-IR), Thermogravimetry analysis (TGA/DTGA) and scanning electron microscopy (SEM). Results obtained from the study revealed that modification was indicative based on the observation of C=O absorption peak at 1722 and 1640 cm^-1 respectively. TGA results revealed blend composition of 0.5/0.5 g gave the best material’s stability. We also observed that the properties of the modified wood flakes/blends were enhanced by the lower equilibrium moisture content caused by acetyl groups. The modified wood flakes could find industrial applications in fiber and particles/plywood board products for various construction purposes while unmodified blends can be used in the production of polymer-based biodegradable products. Biodegradation results indicate that blending of acetylated wood flakes with polyethylene matrix enhanced its biodegradation. Thus, adding acetylated wood flakes into polyethylene could reduce the lifespan of PE in the environment.