Exploring the potential of resorcinol-formaldehyde xerogels as thermal insulators

The contribution to the total thermal conductivity of porous materials depends mainly on the operating conditions and on its type of porosity. Accordingly, the thermal insulating capacities of several resorcinol-formaldehyde (RF) xerogels synthesized by microwave heating were investigated. First, th...

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Detalles Bibliográficos
Autores: Rey Raap, Natalia, Gómez Calvo, Esther, Menéndez Díaz, José Ángel, Arenillas de la Puente, Ana
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2017
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/145864
Acceso en línea:http://hdl.handle.net/10261/145864
Access Level:acceso abierto
Palabra clave:Resorcinol-formaldehyde xerogels
Pore size
Density
Thermal conductivity
Descripción
Sumario:The contribution to the total thermal conductivity of porous materials depends mainly on the operating conditions and on its type of porosity. Accordingly, the thermal insulating capacities of several resorcinol-formaldehyde (RF) xerogels synthesized by microwave heating were investigated. First, the operating conditions were optimized, since the thermal conductivity measurements were to be performed both before and after the degassing of the organic xerogels and with various particle sizes, ranging from 3 mm to below 212 μm. Special attention was paid to the influence of the porous properties, particularly density and pore size, on the total thermal conductivity. A minimum thermal conductivity value of 0.035 W m−1 K−1 was obtained for an organic xerogel with a bulk density of 0.248 g cm−3 and a mean pore size of 144 nm. The results obtained suggest that RF xerogels would be highly suitable candidates for thermal insulation applications as their thermal conductivity values are comparable to those of commercial materials, such as expanded polystyrene (0.034 W m−1 K−1).