Submitted to: Corn Utilization Conference Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: June 6, 1996
Publication Date: N/A
Technical Abstract: Extrusion processing of modified starches can provide a starch-based foamed extrudate with properties similar to expanded polystyrene protective loose-fill. The starch-based loose-fill foams perform well and are biodegradable and have competed well with the expanded polystyrene loose-fill. Polymer-based cushioning materials generally performed better with less material than paper-based and popcorn cushioning materials. Properties of six starch-based extrudates and two commercially expanded polystyrene as protective loose-fill were evaluated after being conditioned in various humidity and temperature environments. Bulk and specimen density, compressive strength, friability, moisture, open-cell content, resiliency, and specimen volume were studied. Compressive strength values for the starch-based foams were greater (17%) than for the synthetic (virgin and recycled) foams. The resiliency of the synthetic foams was greater (20%) than that of the starch foams. Starch foams exhibited bulk densities 2 to 3 times that exhibited by synthetic foams. When specimens were conditioned at 50% relative humidity the starch foams contained 8-10% and the synthetic foams contained only 1-2% moisture. Starch-based foams contained more open cells and the cells were larger. The starch foams were quite low in friability. The specific densities of starch foams were higher than for the synthetic foams. Future work on developing biodegradable loose-fill needs to reduce weight, lower costs, improve quality, and expand technology.