C. Rudaz, A. Demilecamps, G. Pour, M. Alves, A. Rigacci, H. Sallée, G. Reichenauer, T. Budtova
{"title":"Bio-based Aerogels: A New Generation of Thermal Superinsulating Materials","authors":"C. Rudaz, A. Demilecamps, G. Pour, M. Alves, A. Rigacci, H. Sallée, G. Reichenauer, T. Budtova","doi":"10.1002/9781119217619.CH15","DOIUrl":null,"url":null,"abstract":"Aerogels are highly porous, ultra-light (density around 0.1 g/cm3) nanostructured materials. One of their most extraordinary properties is thermal super-insulation, i.e. thermal conductivity below that of the air: 0.015 vs 0.025 W/(m.K) in room conditions. However, classical silica aerogels are extremely fragile and organic/synthetic (resorcinol-formaldehyde) aerogels may include toxic components, which hinders their wide application. Bio-aerogels are a new generation of aerogels made from biomass-based polymers, mainly polysaccharides. We prepared aerogels from cellulose (“aerocellulose” /1, 2/) and pectin (“aeropectin” /3/) via polymer dissolution, coagulation and drying with super-critical CO2. Their density varies from 0.05 to 0.2 g/cm3 and specific surface area is around 200-300 m2/g. Bio-aerogels are mechanically strong, with Young’s moduli from 1-2 to 20-30 MPa and plastic deformation up to 60-70% strain before the pore walls collapse. Aeropectin thermal conductivity turned to be around 0.015 – 0.020 W/(m.K) making it the first reported thermal super-insulating fully biomass-based aerogel. The thermal conductivity of aerocellulose is rather “high”, around 0.030-0.035 W/(m.K), due to the presence of large macropores. We demonstrate that by using polysaccharide functionalization and making polymer-silica aerogel hybrids it is possible to vary specific surface area (increase to 800-900 m2/g) and decrease aerogel thermal conductivity below that of the air.","PeriodicalId":15213,"journal":{"name":"纤维素科学与技术","volume":null,"pages":null},"PeriodicalIF":0.0000,"publicationDate":"2015-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"7","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"纤维素科学与技术","FirstCategoryId":"1087","ListUrlMain":"https://doi.org/10.1002/9781119217619.CH15","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 7
Abstract
Aerogels are highly porous, ultra-light (density around 0.1 g/cm3) nanostructured materials. One of their most extraordinary properties is thermal super-insulation, i.e. thermal conductivity below that of the air: 0.015 vs 0.025 W/(m.K) in room conditions. However, classical silica aerogels are extremely fragile and organic/synthetic (resorcinol-formaldehyde) aerogels may include toxic components, which hinders their wide application. Bio-aerogels are a new generation of aerogels made from biomass-based polymers, mainly polysaccharides. We prepared aerogels from cellulose (“aerocellulose” /1, 2/) and pectin (“aeropectin” /3/) via polymer dissolution, coagulation and drying with super-critical CO2. Their density varies from 0.05 to 0.2 g/cm3 and specific surface area is around 200-300 m2/g. Bio-aerogels are mechanically strong, with Young’s moduli from 1-2 to 20-30 MPa and plastic deformation up to 60-70% strain before the pore walls collapse. Aeropectin thermal conductivity turned to be around 0.015 – 0.020 W/(m.K) making it the first reported thermal super-insulating fully biomass-based aerogel. The thermal conductivity of aerocellulose is rather “high”, around 0.030-0.035 W/(m.K), due to the presence of large macropores. We demonstrate that by using polysaccharide functionalization and making polymer-silica aerogel hybrids it is possible to vary specific surface area (increase to 800-900 m2/g) and decrease aerogel thermal conductivity below that of the air.