DEVELOPMENT OF AGRICULTURALLY-DERIVED BIOPOLYMER COMPOSITES FOR NON-FOOD APPLICATIONS
Location: Bioproduct Chemistry and Engineering Research
Title: In-situ lamination of starch-based baked foam articles with degradable films
Submitted to: Packaging Technology and Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: May 6, 2007
Publication Date: July 27, 2007
Citation: Glenn, G.M., Klamczynski, A., Chiou, B., Imam, S.H., Orts, W.J., Wood, D.F., Ludvik, C.N. 2007. In-situ lamination of starch-based baked foam articles with degradable films. Packaging Technology and Science. 20(2):77-85.
Interpretive Summary: Starch composite foam substrate is used in making single-use food containers. The containers are typically laminated with a film to make them moisture resistant. This study reports the use of biodegradable laminate film that can be applied in the cooking step to make functional single-use food containers.
A technique for making biodegradable food service packaging comprised of a starch/fiber core and a biodegradable film laminate is described. The biodegradable films were made of polylactic acid (PLA), polybutylenesuccinate/terephthalate (PBST), rubber latex and polybutyleneadipate/terephthalate (PBAT). The technique involved an in situ process for laminating a baked foam product in a single step. A critical element of the in situ technique involved using a heat insulating fiber sheet to stabilize heat sensitive laminate films during the baking/lamination process. The PLA, PBST and PBAT laminated samples were baked for 6 min at 120„aC. The latex laminated sample, which was much more heat stable, did not need the insulating sheet and was baked for 3 min at 160„aC. Starch-based foam laminated with PLA, PBST or PBAT generally had higher density and greater tensile and flexural strength than the non-laminated control. Starch foam laminated with a rubber latex film had tensile and flexural properties similar to the non-laminated control due to the low modulus and elasticity of the latex film. The in situ lamination process improved the adhesion of the starch foam core with the fiber sheet, PLA and latex films compared to a post-lamination process. All of the laminate materials provided a low water vapor permeance. The films degraded in a compost mixture but at a much slower rate compared to starch.