Optimisation de mousses de carbone dérivées de tannin par l’étude et la modélisation de leurs propriétés physiques

Abstract : In this PhD work, alveolar materials in the form of carbon cellular and/or reticulated foams were produced in order to study and to model their physical properties. Cellular carbon foams were obtained by pyrolysis under nitrogen flow of rigid foams mainly derived from biomass-based tannins and furfuryl alcohol. The structures of these foams were tailored through the modification of the formulation of their organics precursors. The reticulated foams, only comprising a solid skeleton made of struts without cell walls, were prepared from polymeric commercial foams through a template method. The structures of all of these materials were thoroughly characterised by using different methods such as electron microscopy and X-ray microtomography. The physical properties of these foams were investigated through mechanical, acoustic, thermal and electromagnetic measurements. Mechanical characterisations were carried out in quasi-static compression through a comparative study with or without plates glued to the samples surfaces. The acoustic tests were done with a 2-microphones impedance tube and through air resistivity measurements. The thermal conductivity was investigated by Hot Disk and Laser flash methods, the latter being coupled with thermal expansion and heat capacity measurements. The electromagnetic characterisations were performed in a wide range of frequencies, from 20 Hz to terahertz and far infrared through LRC-meter, network analyser and waveguides, and terahertz and infrared spectrometers. This work allowed studying precisely the influence of different structural parameters such as density and cell size, interconnectivity and shape, as well as tortuosity, on the physical properties of foams. It was finally possible, depending on the cases, to check the validity of existing models, to suggest improvements or limitations, or to observe new phenomena.
Document type :
Theses
File URL :
.
Complete list of metadatas

https://hal.univ-lorraine.fr/tel-01754480
Contributor : Thèses Ul <>
Submitted on : Friday, March 30, 2018 - 9:50:39 AM
Last modification on : Wednesday, September 4, 2019 - 2:06:03 PM

Identifiers

  • HAL Id : tel-01754480, version 1

Citation

Maxime Letellier. Optimisation de mousses de carbone dérivées de tannin par l’étude et la modélisation de leurs propriétés physiques. Autre. Université de Lorraine, 2015. Français. ⟨NNT : 2015LORR0165⟩. ⟨tel-01754480⟩

Share

Metrics

Record views

16