Title: Morphological and mechanical characterization of thermoplastic starch and its blends with polylactic acid using cassava starch and bagasse Authors
|Teixeira, Eliangela DE -|
|Curvelo, Antonio -|
|Correa, Ana -|
|Marconcini, Jose -|
|Mattoso, Luiz -|
Submitted to: Meeting Proceedings
Publication Type: Proceedings
Publication Acceptance Date: August 30, 2011
Publication Date: October 17, 2011
Citation: Teixeira, E.M., Curvelo, A.A., Correa, A.C., Marconcini, J.M., Glenn, G.M., Mattoso, L.H. 2011. Morphological and mechanical characterization of thermoplastic starch and its blends with polylactic acid using cassava starch and bagasse. In: Proceedings of 11th Congresso Brasileiro de Polimeros. Brazilian Association of Polymers: Campos do Jordao, Sao Paulo, Brazil. p. 5666-5670. Interpretive Summary: Agricultural residues are waste byproducts from harvesting crops, thus these residues are renewable. The agricultural residue from the harvest of cassava contains bagasse (straw) and residual starch. The incorporation of the cassava residues into value-added products would benefit the economy and the environment by creating useful products, reducing waste streams and lessen the reliance on petroleum products that are currently used to produce plastics. These residues may serve as reinforcing agents in plastics, such as poly(lactic acid) (PLA), a biodegradable polymer, to increase the thermal and mechanical properties of the resulting product. Test panels made from the composited cassava residues and PLA show promise as potential products that would replace part of the plastics market.
Technical Abstract: This study aims the use of an agro waste coming from the industrialization of cassava starch, known as cassava bagasse (BG). This material contains residual starch and cellulose fibers which can be used to obtain thermoplastic starch (TPS) and /or blends reinforced with fibers. In this context, it was prepared a thermoplastic starch with BG (TPSBG) and evaluated the incorporation of 20 wt% of it into the biodegradable polymer poly (lactic acid) (PLA), resulting in a blend PLA/TPSBG20. The materials were investigated through morphology (scanning electron microscopy with field emission gun (FEG), x-ray diffraction (XRD), and mechanical behavior (tensile test). Their properties were compared to the blend PLA/TPSI20 in which TPSI is obtained from commercial cassava starch. The results showed that the use of bagasse generates homogenous materials with higher mechanical strength if compared to TPS obtained from commercial cassava starch. The fiber in this residue acted as reinforcement for TPS and PLA/TPS systems.