Evaluating distillers grains as bio-fillers for high-density polyethylene

Bio-composites are known to have poor properties. The reason is the absence of chemical bonding between bio-fillers and polymers. In this present study, we prepared composites with a bio-filler by melt blending distillers grains (DG) with high-density polyethylene (HDPE) and modified HDPE (MHDPE), and compared the characteristics of the composites. Differential scanning calorimetry, thermogravimetry, mechanical property measurement, Fourier transform infrared spectroscopy, contact angle measuring instrument, and water absorption analysis were used to assess DG as a bio-filler. From the results of hydrophilicity measurement, water absorption, morphology, and tensile strength tests, MHDPE was found to have a better interfacial adhesion with DG. The yield strength and crystallinity of DG/MHDPE bio-composites with 50% DG were higher than those of pure HDPE. As DG improved the bio-composite performance, it would have broad application prospects as a bio-filler.