OATAO - Open Archive Toulouse Archive Ouverte Open Access Week

Thermal insulation blocks made of sunflower pith particles and polysaccharide-based binders: influence of binder type and content on their characteristics

Laborel-Preneron, Aurélie and Ampe, Clara and Labonne, Laurent and Magniont, Camille and Evon, Philippe Thermal insulation blocks made of sunflower pith particles and polysaccharide-based binders: influence of binder type and content on their characteristics. (2022) Construction Technologies and Architecture, 1. 43-50. ISSN 2674-1237

(Document in English)

PDF (Author's version) - Requires a PDF viewer such as GSview, Xpdf or Adobe Acrobat Reader

Official URL: https://doi.org/10.4028/www.scientific.net/CTA.1.43


Co-product of sunflower cultivation, pith of stem has a little exploited insulating potential. Blocks in which pith particles are glued together using a starch-based binder have already been obtained. However, they are highly water-sensitive. Replacing this binder with others has been considered here. Polysaccharide-based binders were tested, chosen for their more hydrophobic character: sodium alginate, chitosan, Citrus pectin, and a modified starch. Like starch, these binders are physically binding. They are first solubilised in water (except chitosan, dissolved in 2% acetic acid). The solution is then mixed with pith particles before cold compression molding for 90 s. A 10% binder content was initially considered. The blocks were all cohesive with a dry density from 36 to 42 kg/m3). Their performances were assessed through water absorption capacity and resistance via capillary absorption tests on wet sponges, mechanical test and thermal conductivity. Chitosan and pectin-based blocks show the best properties, particularly concerning water resistance and mechanical properties. The pectin-based block has improved its elastic modulus by 40% compared to a starch-based block. The pectin-based block in its case absorbs 2.7 times less water than starch. Finally, thermal conductivities of pectin and chitosan-based pith blocks are in the same order of magnitude as for starch (39.8-40.1 mW/m.K), and close to values from commercial materials (e.g., polystyrene). Pectin and chitosan were also tested at three rates (5%, 10% and 15%). A significant improvement in the blocks' compressive strength was observed with the increase in binder rate, while thermal conductivities varied little.

Item Type:Article
Additional Information:Diffusion en l'absence de réponse à notre demande du 28/01/22.
HAL Id:hal-04490064
Audience (journal):International peer-reviewed journal
Uncontrolled Keywords:
Institution:French research institutions > Centre National de la Recherche Scientifique - CNRS (FRANCE)
Université de Toulouse > Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE)
French research institutions > Institut national de recherche pour l'agriculture, l'alimentation et l'environnement - INRAE (FRANCE)
Université de Toulouse > Institut National des Sciences Appliquées de Toulouse - INSA (FRANCE)
Université de Toulouse > Université Toulouse III - Paul Sabatier - UT3 (FRANCE)
Laboratory name:
Deposited On:14 Mar 2022 15:10

Repository Staff Only: item control page