Study of an insulating hemp-based bio-material: mechanical, thermal and acoustic properties

Currently there is a need to develop more sustainable and renewable materials compromised with the environment. From these needs, hemp stalk has great potential because it is mostly a waste material. Moreover, hemp shives are a lightweight material with a high insulating property. This study aims to...

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Detalhes bibliográficos
Autores: Martínez Martínez, Borja|||0000-0002-4398-1983, Gil Espert, Lluís|||0000-0002-2007-4846, Bernat Masó, Ernest|||0000-0002-7080-0957
Formato: artículo
Fecha de publicación:2022
País:España
Recursos:Universitat Politècnica de Catalunya (UPC)
Repositorio:UPCommons. Portal del coneixement obert de la UPC
Idioma:inglés
OAI Identifier:oai:upcommons.upc.edu:2117/386418
Acesso em linha:https://hdl.handle.net/2117/386418
https://dx.doi.org/10.23967/r.matcomp.2022.07.045
Access Level:acceso abierto
Palavra-chave:Biomaterials
Stalk
Insulating composite biomaterial
Mechanical performance
Sustainability Cañamiza
Biomaterial compuesto aislante
Propiedades mecánicas
Sostenibilidad
Materials de construcció
Àrees temàtiques de la UPC::Edificació::Materials de construcció::Nous materials de construcció
Descrição
Resumo:Currently there is a need to develop more sustainable and renewable materials compromised with the environment. From these needs, hemp stalk has great potential because it is mostly a waste material. Moreover, hemp shives are a lightweight material with a high insulating property. This study aims to increase the knowledge in a material made solely from stalk and ECF (elementary chlorine free) bleached eucalyptus kraft pulp and a second 100% recycled material where the kraft pulp is replaced by recycled cardboard fiber, also a vegetable coating is added to protect against moisture. The hemp/fiber ratio influence is studied. Samples are evaluated in terms of mechanical behaviour (compression and shear), thermal and acoustic insulation. To study the thermal insulation, a testing camera is used where the heat transfer through the material is measured in order to study the thermal resistance. A Kundt tube is used in the acoustic insulation study to calculate the absorption of sound waves in a range from 0 to 6500 Hz. The results show that by increasing the percentage of hemp, the mechanical properties increase (compression and shear). Also, the eucalyptus pulp acts as a binder between the shives; nevertheless, if there is not enough, the material is not stable. Therefore, a maximum of 70 wt.% of hemp is recommended. In the case of thermal insulation, better thermal resistance is obtained in the case of 60 wt.% of hemp, while in acoustic insulation a higher percentage of hemp have a high performance, reaching attenuation values greater than 0.8 for frequencies greater than 1000Hz. The carboard sample improves the shear and acoustic insulation performance. The coating improves the thermal resistance but worsens the acoustic insulation.