PLA-Based Nanocomposites Reinforced with CNC for Food Packaging Applications: From Synthesis to Biodegradation

The costs of biobased and biodegradable polymers are generally still much higher than that of their traditional polymer counterparts Frequently used in the food packaging field. Although PLA is currently used in the market in several packaging applications,its potential to substitute petrochemical-based polymers has not yet been realized in full perspective. The reinforcing effect of CNC has a large potential inenhancing the crystallinity of PLA that could result in higher tortuosity of the transport path improving the typically low barrier properties of PLA. However, the high polarity of CNC surface should be reduced for the industrial melt processing of PLA?nanocellulose-based materials. The surface functionalization by means of the use of a surfactant is an easy way to improve the dispersion of CNC into PLA matrix.The well dispersion of cellulosic nanoparticles achieved during nanocomposite processing has a large potential in improving the mechanical performance. Additionally, the CNC presence also accelerates the degradation rate of the PLA-based nanocomposites.These bionanocomposites are promising candidates for sustainable post-use waste treatments, such as composting, when short biodegradation times are required like the case of food packaging.Fil: Arrieta, M. P.. Consejo Superior de Investigaciones Científicas; EspañaFil: Peltzer, Mercedes Ana. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología. Área Ingeniería en Alimentos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: López, J.. Universidad Politécnica de Valencia. Instituto de Tecnología de Materiales; EspañaFil: Peponi, L.. Consejo Superior de Investigaciones Científicas; Españ

Morphological variation and different branch modularity across contrasting flow conditions in dominant Pocillopora reef-building corals

© 2015, Springer-Verlag Berlin Heidelberg. Pocillopora corals, the dominant reef-builders in the Eastern Tropical Pacific, exhibit a high level of phenotypic plasticity, making the interpretation of morphological variation and the identification of species challenging. To test the hypothesis that different coral morphospecies represent phenotypes that develop in different flow conditions, we compared branch characters in three Pocillopora morphospecies (P.damicornis, P. verrucosa, and P. meandrina) from two communities in the Gulf of California exposed to contrasting flow conditions. Morphological variation and branch modularity (i.e., the tendency of different sets of branch traits to vary in a coordinated way) were assessed in colonies classified as Pocillopora type 1 according to two mitochondrial regions. Our results can be summarized as follows. (1) Pocillopora type 1 morphospecies corresponded to a pattern of morphological variation in the Gulf of California. Overall, P.damicornis had the thinnest branches and its colonies the highest branch density, followed by P.verrucosa, and then by P.meandrina, which had the thickest branches and its colonies the lowest branch density. (2) The differentiation among morphospecies was promoted by different levels of modularity of traits. P.verrucosa had the highest coordination of traits, followed by P.damicornis, and P.meandrina. (3) The variation and modularity of branch traits were related to water flow condition. Morphology under the high-flow condition was more similar among morphospecies than under the low-flow condition and seemed to be related to mechanisms for coping with these conditions. Our results provide the first evidence that in scleractinian corals different levels of modularity can be promoted by different environmental conditions