Dried distillers grains with solubles as a multifunctional filler in low density wood particleboards

• Use of DDGS in wood particleboards increased the mechanical strength of particleboards.
• The DDGS proteins bonded with melamine urea formaldehyde resin and improve fiber bonding.
• The oil in DDGS helped to improve the water resistance of particleboards.

In recent years, corn has been widely used to produce ethanol. Roughly for every 25.4 kg of corn processed, 8.16 kg of Dried Distillers Grains with Solubles (DDGS) and 11 l of ethanol are produced. The amount of DDGS produced is steadily increasing since 1990 with 35 million metric tonnes produced in 2012. DDGS has been investigated for its use as a functional filler in low density wood particleboards bonded with 10 wt.% (wt.%) Melamine Urea Formaldehyde and 10 wt.% AW-50 paraffin wax emulsion for water resistance. Both the concentration of the DDGS filler – 5, 10, and 15 wt.% – and the particle size of the filler – 125, 300, and 500 μm – has been considered in this experiment. It was presumed that the additional protein and fats in the lignocellulosic DDGS would increase the mechanical strength and the water resistance of the particleboards. Chemical analysis, thermogravimetric analysis, differential scanning calorimetry, transform infrared spectroscopy, and 13C NMR were used to analyze the DDGS filler. The analysis showed that the chemical composition of DDGS was not altered by micronization. A variety of mechanical tests were performed following ASTM D1037 including flexural, internal bond, screw withdrawal, and water absorption. The results show that at concentrations of 5 wt.% DDGS with particles of 500 μm produced superior properties compared to the control panel from the water absorption, flexural, and internal bond tests. The screw withdrawal test produced equivalent properties to the control. This work demonstrates that DDGS can be used as multifunctional filler in particleboards.