Protective Loose-Fill Foams

Tatarka PD, Cunningham RL. Properties of protective loose-fill foams. J Appl Polym Sci 1998 67 1157. 

The main use of thermoplastic starch alone is in foam applications. Starch-based foams have been found to be an effective alternative to PS foam in loose-fill protective packaging. Starch-based foams offer the advantage that they are readily biodegradable if they escape into the environment. They also offer superior antistatic properties. Starch-based foam, however, has some disadvantages it is brittle and the density is higher than PS. Foamed, starch-based articles are prepared by heating starch in an extruder in the presence of water with subsequent extrusion. 

Polylactide has high potential in agricultural applications such as mulch films either in pure form or blended with other polymers such as thermoplastic starch. In addition, polylactide is used in compostable yard bags and dog poop bags. Lactic acid based hot-melt adhesives have also been developed (90). Foamed PLA could be used as structural protective foams, loose-fill packaging and insulation material as an alternative for expanded polystyrene (EPS). While packaging is currently the high volume application... 

Thermoplastic starch can be used to obtain foams useful as effective alternatives to PS in loose-fill protective packaging, and possibly as thermal or acoustic insulating materials. 

Although the use of starch in loose-fill products gives advantages in the form of biodegradability and environmental protection, these products have been criticized for their imperfection in relation to EPS loose-fiU products. EPS- and starch-based foams have differences, but the differences do not compromise performance. 

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