Development of biodegradable plastics by blending a by-product of the corn based ethanol industry and poly (epsilon-caprolactone)

Development of new value-added green materials from byproducts of corn-based ethanol industries would provide a substantial economic return to the corn growers. Corn gluten meal (CGM), a major byproducts of corn-based wet milling ethanol industries has most of its use as livestock feed. In this research CGM was plasticized using glycerol/ethanol mixture, destructurized by the addition of guanidine hydrochloride (GHCl) and then blended with poly (epsilon-caprolactone) (PCL). Extrusion followed by injection molding was adopted to fabricate the newly blended bioplastics/green materials. The GHCl modified corn gluten meal was characterized by infra-red (IR) spectroscopy. The effect of processing conditions on properties of blends was investigated. The thermo-mechanical properties of the blends were studied using DMA (Dynamic Mechanical Analyzer), TGA (Thermo-Gravimetric Analyzer) and UTS (Universal Testing System). Significantly higher elongation and an almost equivalent tensile strength was observed for GHCl modified blend in contrast to the non-GHCl modified blend. The blends were also observed to be more thermal stable with addition of GHCl. Scanning electron microscopy (SEM) was used to study the surface morphology of the blends. The SEM analysis revealed better compatibility of PCL with GHCl modified plasticized CGM in contrast to plasticized CGM.