Biocomposites for value addition to agricultural waste: Industry partnership for product development

Authors: BAJWA, SREEKALA - North Dakota State University; BAJWA, DILPREET - North Dakota State University; PANDEY, PANKAJ - North Dakota State University; Holt, Gregory

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 12/30/2017
Publication Date: N/A
Citation: N/A

Interpretive Summary:

Technical Abstract: Rationale: The agricultural industry produces vast amounts of cellulosic byproducts during production and processing. For example, US produced 39 million tons of DDGS and over 2.5 million tons of cotton gin waste in 2015. According to Biotechnology Industry Organization, 428 million tons of agricultural residue will be available in the US by 2030 for bioenergy/bioproduct applications. The current slump in bioenergy industry, and growing interest in bioproducts industry has created strong interests in the use agricultural residue in biocomposites. Objectives: The objective of this research was to develop and test new biocomposite materials utilizing agricultural residues to develop commercially viable products, in partnership with industry. Method: This study focused on two agricultural wastes, cotton burr and stem (CBS) fibers from gin waste, corn hull fibers from corn grain and distillers dry grain with solubles (DDGS) as potential fillers for biocomposites with high density polyethylene (HDPE) as a polymer substrate. The HDPE composite samples were initially manufactured at lab-scale with different fiber filler composition to evaluate the agricultural fibers as potential replacement for wood in wood polymer composites (WPCs). The most viable HDPE composite formulations were evaluated at commercial scale with industry partnership. The hull fibers from DDGS, and feed corn were also evaluated with a petroleum-based HDPE and a biobased HDPE at lab scale. All composites were manufactured by a combination of extrusion and injection molding at lab scale and extrusion at the commercial scale. The composite samples were evaluated for their physico-mechanical properties such as tensile or flexural strength and modulus, impact strength, surface hardness, water absorption, specific gravity, and coefficient of linear thermal expansion, following specific ASTM standards. Results: Both CBS and DDGS fibers showed great potential as a replacement for wood fiber in commercial WPCs. The physico-mechanical properties of HDPE composites with CBS was similar to that of WPC at substitution levels of up to half of the fiber fraction. Similarly, hull fibers from DDGS and feed corn showed some remarkable properties and good potential at lab and commercial scale. Biobased HDPE composite with DDGS and corn fiber showed some remarkably better water absorption and impact resistance. Conclusion: The study indicates that cellulosic fibers from the two agricultural sources can be partial substitutes for wood fiber fillers in polymer composites without any degradation of their performance characteristics. For non-structural applications that do not rely on strength properties, these agricultural fibers can fully substitute the fiber fraction in WPC. Industrial partnership was vital in proving the commercial validity to industry, and acceptance of the material from industry partners.