(81d) Flexible Extruded Sheets From Low Cost Soymeal

Mohanty, A. K., University of Guelph
Misra, M., University of Guelph
Reddy, M. M., University of Guelph

One of the biggest challenges of plastic menace arises from their one trip applications like shopping bags, packaging films etc. This problem can be better handled by developing affordable and compostable materials. Soy protein which is a natural biopolymer offers biodegradability and renewability is used in its crude form (soybean meal) to develop compostable sheets for packaging.

Soy proteins are stabilized and strengthened by hydrogen bonds, hydrophobic interactions and disulfide bonds and these provide strength and stiffness to proteins in the solid-state. However, this stability observed in proteins becomes hurdle during their processing in melt state. In our approach, we overcome this by dry processing of soybean meal with plasticizers and reducing agents to obtain bioplastic. FTIR confirmed that urea additive helped in destructurization of soybean meal by breaking hydrogen bonds and disulphide bridges in soy protein. Reactive extrusion of soybean bioplastic and flexible biodegradable polyester was carried out in a twin screw extruder to obtain thermoplastic soy blends. Furthermore, cast film processing of thermoplastic soy blends were carried out in single screw microtruder. Cooling rate, throughput, roll speed have significant effect on the film properties.

This work is financially supported by Hannam soybean utilization 2008 fund and the Ontario Ministry of Agriculture, Food and Rural Affairs (OMAFRA) 2009 New Directions & Alternative Renewable Fuels Research Program Project number SR9223.