Submitted to: BioResources
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/17/2007
Publication Date: 1/19/2007
Citation: Mikkonen, K., Yadav, M.P., Cooke, P.H., Willfor, S., Hicks, K.B., Tenkanen, M. 2008. Films from spruce galactoglucomannan blended with poly(vinyl alcohol), corn arabinoxylan and konjac glucomannan. BioResources. 3(1):178-191. Interpretive Summary: The need to find new uses for low value by-products obtained from agricultural processing and mechanical pulping of wood has prompted us to develop biodegradable films designed for industrial use. These films are made from plant polymers obtained from by-products, plus poly (vinyl) alcohol and glycerol. The polymers arabinoxylan and galactoglucomannan are prepared from the low value by-products of corn wet milling and spruce mechanical pulping respectively. Glycerol is a biofuel co-product. In this work we show that a mixture of plant polymers, poly (vinyl) alcohol, and glycerol can make biodegradable films. The right combination of these materials can make a strong film with good resistance to moisture, air and grease. They can be used as packaging materials. Commercialization of these films will provide new uses for agricultural by-products and more revenue for farmers, processors and manufacturers of agricultural materials.
Technical Abstract: The improvement of mechanical properties of spruce galactoglucomannan (GGM)-based films was sought by blending GGM with each of poly(vinyl alcohol) (PVOH), corn arabinoxylan (cAX), and konjac glucomannan (KGM). The blend ratios were 3:1, 1:1, and 1:3(w/w), and in addition films were made from each of the polymers alone. Glycerol was used as plasticizer. Adding other polymers increased the elongation at break of GGM blend films. The tensile strength of films increased with increasing amount of PVOH and KGM, but the effect of cAX was the opposite. Dynamic mechanical analysis showed two separate loss modulus peaks for blends of GGM and PVOH, but a single peak for all other films. Optical and scanning electron microscopy confirmed good miscibility of GGM with cAX and KGM. In contrast, films blended from GGM and PVOH showed phase separation when examined by microscopy.