|MOREIRA, F.K.V - Embrapa|
|PEDRO, D.C.A - Embrapa|
|Glenn, Gregory - Greg|
|MARCONCINI, J.C - Embrapa|
|MATTOSO, LUIZ H. - Paraiba University|
Submitted to: Journal of Applied Polymer Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/1/2012
Publication Date: 11/14/2012
Citation: Moreira, F., Pedro, D., Glenn, G.M., Marconcini, J., Mattoso, L. 2012. Brucite nanoplate reinforced starch bionanocomposites. Journal of Applied Polymer Science. 92(20):1743-1751.
Interpretive Summary: Interpretive Summary. Starch-based plastic films often have poor mechanical properties. ARS researcher, Dr. Glenn, collaborated with Embrapa researchers to investigate the effect of brucite nanoparticles in improving the properties of starch films. The brucite nanoparticles formed plate-like structures with an aspect ratio of 9.25. Brucite is a GRAS material and was effective in increasing the strength and stiffness of starch films. The optimum concentration was in the range of 1% by weight. Higher concentrations of brucite formed agglomerates that negatively affected film strength. This research could help promote further commercialization of starch-based plastics for industrial applications.
Technical Abstract: In this paper the mechanical reinforcement in a series of bionanocomposites films based on starch and nano-sized brucite, Mg(OH)2, was investigated. Brucite nanoplates with an aspect ratio of 9.25 were synthesized by wet precipitation and incorporated into starch matrices at different concentrations (0-7.5 wt.%). Scanning electron microscopy revealed a high degree of nanoplates dispersion within the starch bionanocomposites and good interfacial adhesion between filler and matrix. The brucite nanoplates formed agglomerates at high concentrations. Reinforcement factor values of the bionanocomposites were higher than predicted values from the Halphin-Tsai model, which was attributed mainly to the high surface area of nanoplates. Brucite (1 wt.%) nearly doubled the tensile strength of starch films. Thermogravimetric analyses indicated some interactions between starch and brucite that modified their decomposition profiles. Mechanical tests of glycerol plasticized bionanocomposites showed that the reinforcing efficiency of brucite remained high even at 10 wt.% and 20 wt.% of plasticizer.