The chemical composition and morphology of Syngonanthus nitens (Capim Dourado) fibers were investigated. An unusual low lignin content and high holocellulose content have been observed. High aspect ratio cellulose whiskers were prepared from these lignocellulosic fibers by an acid hydrolysis treatment. The average diameter and length were 4.5 nm and 300 nm, respectively, giving rise to an aspect ratio around 67. Natural Rubber nanocomposite films reinforced with cellulose whiskers extracted from capim dourado were prepared by film casting. The mechanical properties of the ensuing nanocomposite films were investigated in both the linear and the nonlinear range using dynamical mechanical analysis and tensile tests, respectively. The reinforcing effect observed above the glass transition temperature of the matrix was higher than the one observed for other polysaccharide nanocrystals and cellulose whiskers extracted from other sources.

. Influence of citric acid and water on thermoplastic wheat flour/poly(lactic acid) blends. I: Thermal, mechanical and morphological properties. Industrial Crops and Products, Elsevier, 2012, vol. 37, pp. 238-246 Wheat flour was plasticized with glycerol and compounded with poly(lactic acid) in a one-step twinscrew extrusion process in the presence of citric acid with or without extra water. The influence of these additives on process parameters and thermal, mechanical and morphological properties of injected samples from the prepared blends, was then studied. Citric acid acted as a compatibilizer by promoting depolymerization of both starch and PLA. For an extrusion without extra water, the amount of citric acid (2 parts for 75 parts of flour, 25 parts of PLA and 15 parts of glycerol) has to be limited to avoid mechanical properties degradation. Water, added during the extrusion, improved the whole process, minimizing PLA depolymerization, favoring starch plasticization by citric acid and thus improving phases repartition.

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