ARS | Publication request: Evaluation of cotton byproducts as fillers for poly(lactic acid) and low density polyethylene

Submitted to: Industrial Crops and Products
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: August 23, 2011
Publication Date: September 28, 2011
Citation: Sutivisedsak, N., Cheng, H.N., Dowd, M.K., Selling, G.W., Biswas, A. 2012. Evaluation of cotton byproducts as fillers for poly(lactic acid) and low density polyethylene. Industrial Crops and Products. 36:127-134.

Interpretive Summary: The objective of this study was to develop new uses for waste and agricultural byproducts; cotton burr and cottonseed hull in efforts to promote green chemistry and to find applications with higher value. Commercialization of PLA has been inhibited to some extent because of its relatively high price. Cotton burr is a byproduct of cotton harvesting and ginning and cottonseed hull is a byproduct of cottonseed oil extraction. Cottonseed hulls are currently used as roughage in animal feed, as a garden or field mulch, or as a component of the growth media for mushroom production. Cotton burrs are often used as fuel for boilers or occasionally as mulch. Both materials are readily available and inexpensive. In this article, both byproducts are evaluated as possible filler materials in poly(lactic acid) (PLA) and low-density polyethylene (LDPE) composites. The use of byproducts, cotton burr and cottonseed hull as filler improved the biodegradability plastic blends. This study will benefit the cotton growers by providing them with a new way to utilize the byproducts of cotton production.

Technical Abstract: Polymeric composites based on cotton burr and cottonseed bull have been prepared by melt blending and extrusion. For poly(lactic acid) (PLA) and low-density polyethylene (LDPE), addition of the fillers only slightly changed the composite’s thermal properties and significantly decreased the composite’s mechanical properties. Heat treatment prior to extrusion resulted in composites with better tensile strength and Young’s modulus. The use of maleic anhydride and peroxide only slightly improved the physical properties of the LDPE materials, but the effect was less clear for the PLA materials. The PLA-filler composites may be useful for lowering the cost of the materials in applications that can tolerate the decreased properties. The addition of fillers to LDPE might be beneficial in applications to improve stiffness or to improve biodegradability.