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3 results on '"Aurelio Barbetta"'

1. Composition dependent Equation of State of cellulose based plant tissues in the presence of electrolytes

Author

Th. Zemb, Aurelio Barbetta, Luca Bertinetti, Department of Biomaterials [Potsdam], Max Planck Institute of Colloids and Interfaces, Max-Planck-Gesellschaft-Max-Planck-Gesellschaft, Tri ionique par les Systèmes Moléculaires auto-assemblés (LTSM), Institut de Chimie Séparative de Marcoule (ICSM - UMR 5257), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), and Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)

Subjects
040101 forestry, Equation of state, Nanocomposite, Absorption of water, technology, industry, and agriculture, [CHIM.MATE]Chemical Sciences/Material chemistry, 04 agricultural and veterinary sciences, 02 engineering and technology, 021001 nanoscience & nanotechnology, complex mixtures, chemistry.chemical_compound, Colloid and Surface Chemistry, chemistry, Chemical engineering, Polymer chemistry, 0401 agriculture, forestry, and fisheries, Lignin, Osmotic pressure, Relative humidity, Cellulose, 0210 nano-technology, Secondary cell wall, ComputingMilieux_MISCELLANEOUS
Abstract

Cell walls of so-called “wood-materials” are constituted by a complex, highly anisotropic and hierarchically organized nanocomposite, characterized by stiff crystalline cellulose nano-fibers, parallel to each other, and embedded in a softer and less anisotropic matrix of hemicelluloses, lignin and water. This matrix is hygroscopic, and therefore swells with increasing humidity. Consequently, wood cells undergo large dimensional changes. A minimal model of wood secondary cell walls to predict water absorption has recently been developed by Bertinetti and co-workers [1] in the form of an Equation of State (EOS) that represents equivalently the water sorption versus relative humidity, as considered in chemical engineering, or the relation between osmotic pressure and volume of solutes, in the physical chemistry equation of state approach initiated by Jean Perrin. We extend hereby this model to the presence of electrolytes adsorbed in the gel part wood cell wall and compare compression wood cell walls to the extreme case of coir.

Published
2017
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2. Nano-, meso- and macro-swelling characterization of impregnated compression wood cell walls

Author

J. Lautru, Renaud Podor, Thomas Zemb, Aurelio Barbetta, Luca Bertinetti, Department of Biomaterials [Potsdam], Max Planck Institute of Colloids and Interfaces, Max-Planck-Gesellschaft-Max-Planck-Gesellschaft, LIA RECYCLING CNRS-MPIKG, Centre National de la Recherche Scientifique (CNRS), Tri ionique par les Systèmes Moléculaires auto-assemblés (LTSM), Institut de Chimie Séparative de Marcoule (ICSM - UMR 5257), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Etude de la Matière en Mode Environnemental (L2ME), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Max-Planck-Gesellschaft, and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)

Subjects
0106 biological sciences, Aqueous solution, Materials science, Forestry, Sorption, 02 engineering and technology, Plant Science, [CHIM.MATE]Chemical Sciences/Material chemistry, 021001 nanoscience & nanotechnology, 01 natural sciences, Industrial and Manufacturing Engineering, Adsorption, Ionic strength, Macroscopic scale, 010608 biotechnology, Ultimate tensile strength, medicine, Osmotic pressure, General Materials Science, Swelling, medicine.symptom, Composite material, 0210 nano-technology, ComputingMilieux_MISCELLANEOUS
Abstract

Wood cell walls when contacted with humid atmosphere or an aqueous solution containing electrolytes or polymers undergo the phenomenon of swelling. In this work, experimental data were produced to quantify the effects of the adsorption water and solutes, which were introduced in the material by equilibration with a solution used as osmotic reservoir. For this reason, different environmental setups have been developed, allowing the control of temperature, water chemical potential, and ionic strength during the sorption process. The aim of this paper is to describe three experimental setups, focused on different levels: at the nanometric scale, small-angle scattering at controlled humidity; at the mesoscopic scale, environmental scanning electron microscopy; and at the macroscopic scale, tensile stage involving immersion of samples in solutions. Applicability and efficiency of the three setups are described. Moreover, it was shown how the combination of the results obtained via the three methodologies can be compared to expectations from a general Equation of State (EOS approach), where wood swelling with water and salt solutions is presented as the dependence of the distance between adjacent cellulose fibrils on the osmotic pressure. The total pressure calculated takes into account chemical, colloidal and mechanical terms in the force balance of the wood cell wall.

Published
2018
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3. Impregnation and Swelling of Wood with Salts: Ion Specific Kinetics and Thermodynamics Effects

Author

Thomas Zemb, Aurelio Barbetta, Peter Fratzl, Luca Bertinetti, Tri ionique par les Systèmes Moléculaires auto-assemblés (LTSM), Institut de Chimie Séparative de Marcoule (ICSM - UMR 5257), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Max Planck Institute of Colloids and Interfaces, Max-Planck-Gesellschaft, and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Salt (chemistry), 02 engineering and technology, 010402 general chemistry, 01 natural sciences, Ion, Colloid, chemistry.chemical_compound, Adsorption, Interstitial matrix, Polymer chemistry, medicine, Cellulose, ComputingMilieux_MISCELLANEOUS, chemistry.chemical_classification, Mechanical Engineering, [CHIM.MATE]Chemical Sciences/Material chemistry, 021001 nanoscience & nanotechnology, 0104 chemical sciences, Chaotropic agent, chemistry, Chemical engineering, 13. Climate action, Mechanics of Materials, Swelling, medicine.symptom, 0210 nano-technology
Abstract

The effects of salt impregnation are studied within wood cell walls, occurring upon soaking from concentrated salt solutions. Osmotic deswelling is in some cases followed by ion specific swelling linked to Hofmeister effects. Taking into account microstructure, this study models the free energy changes associated with the ions and water uptake at molecular, colloidal, and macroscopic mechanical scales, to show that slow swelling until osmotic equilibrium originates from charge separation of the salt diffused into wood cell wall material. Kinetic effects as well as mechanical effects linked to transfer of species and swelling of the interstitial matrix between cellulose crystals are discussed. Predictions by minimal models taking into account nonelectrostatic ion complexation allow to estimate the order of magnitude of the nonelectrostatic binding free energy of adsorbed chaotropic anions and complexed divalent cations to be 8 and 10 kJ mole–1, respectively.

Published
2016
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