Cellulosic-crystals as a fumed-silica substitute in vacuum insulated panel technology used in building construction and retrofit applications

Abstract

Cellulosic-crystals as a fumed-silica substitute in vacuum insulated panel technology used in building construction and retrofit applications, Energy and Buildingshttp://dx.doi.org/10. 1016/j.enbuild.2017.08.058 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. AbstractThis article investigates impact of substituting fumed silica with a cellulosic-crystal innovation in a commercial Vacuum Insulated Panel (VIP) core. High building performance demands have attracted VIP technology investment to increase production capacity and reduce cost. In building retrofit VIPs resolve practical problems on space saving that conventional insulations are unsuitable for. Three challenges exists in fumed silica: cost, low sustainability properties, and manufacture technical maturity. Cellulosic nano-crystal (CNC) technology is in its infancy and was identified as a possible alternative due to a similar physical nano-structure, and biodegradability. The study aim was to determine a performance starting point and establish how this compares with the current benchmarks. Laboratory cellulosic-crystal samples were produced and supplied for incorporation into commercial VIP manufacture. A selection of cellulosic-panels with core densities ranging 127 -170 kg/m 3 were produced. Thermal conductivities were tested at a pressure of 1 Pa (0.01 mBar), with the results compared against a selection of fumed silica-VIPs with core densities ranging 144 -180 kg/m 3 . Conductivity tests were then done on a cellulosic-VIP with 140 kg/m 3 density, under variable pressures ranging 1 -100,000 Pa (0.01 -1000 mBar). This investigated panel lifespan performance, with comparisons made to a fumed silica-VIP of similar core density. Manufactured cellulosic-samples were found unsuitable as a commercial substitute, with performance below current standards. Areas for cellulosic nano-material technology development were identified that show large scope for improvement. Pursuit could create a new generation of insulation materials that resolve problems associated with current commercial versions. This is most applicable in building retrofit where large ranges of domestic and commercial cases are marginalised from their construction markets due to impracticalities and high upgrade costs. This being a problem in multiple economies globally. Figure 3 with typical layer thicknesses [1,13].VIP thermal conductivities are five to ten times lower than commercial insulations, with the centreof-panel reaching 4 mW/m.K [3,4,14,16]. Albeit excellent performance, the technology is expensive with panel prices multiples of five to ten that of standard insulations [...

Effect of Foaming Temperature on Microstructure, Mechanical Properties and Flame Spread Rate in PET–PEN Copolymer

“…Since PEN has superior barrier properties, it is used in making high-performance sailcloth and film. Recently, partial foams of cellulose crystals and copolymers (polyethylene terephthalate-polyethylene naphthalate, PET-PEN) have been investigated as a substitute for VIP core [25,26]. The PET-PEN copolymer for additive manufacturing has emerged as an environmentally benign material for kitchen and decoration applications.…”

Comparative life cycle assessment of different vacuum insulation panel core materials using a cradle to gate approach

“…Novel alternative core materials have also been proposed to reduce the reliance on pyrogenic silica VIP for application in buildings. Tetlow and their co-researchers investigated the use of cellulosiccrystals as a core material due to its similar physical structure to pyrogenic silica and biodegradability (Tetlow et al, 2017). Thermal conductivity tests revealed that despite its positive physical and environmental properties, it could not rival pyrogenic silica's thermal properties.…”

Multi-criteria assessment approach for a residential building retrofit in Norway

“…Most existing research works are focused on the investigation of potential energy savings and the economic aspects of the selected conventional energy retrofit measures (related to building fabric retrofits [9][10][11][12][13]) in Northern [14][15][16][17][18][19] and Southern [20][21][22] parts of Europe. Ciulla et al [11] investigated the energy saving and economic impact for two typical buildings in four Italian cities.…”