Thermal insulation blocks made of sunflower pith particles and polysaccharide-based binders: influence of binder type and content on their characteristics - Archive ouverte HAL Accéder directement au contenu
Article Dans Une Revue Construction Technologies and Architecture Année : 2022

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

Résumé

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.
Fichier principal
Vignette du fichier
Laborel-Preneron_28719.pdf (904.68 Ko) Télécharger le fichier
Origine : Fichiers produits par l'(les) auteur(s)

Dates et versions

hal-04490064 , version 1 (05-03-2024)

Identifiants

Citer

Aurélie Laborel-Preneron, Clara Ampe, Laurent Labonne, Camille Magniont, Philippe Evon. Thermal insulation blocks made of sunflower pith particles and polysaccharide-based binders: influence of binder type and content on their characteristics. Construction Technologies and Architecture, 2022, 1, pp.43-50. ⟨10.4028/www.scientific.net/CTA.1.43⟩. ⟨hal-04490064⟩
54 Consultations
0 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More