S. Ren
University at Buffalo - The State University of New York,
United States
Keywords: transparency, aerogel, mechanical durability, ambient pressure drying
Summary:
We propose roll-to-roll (R2R) manufacturing of silica aerogel for thermal insulation materials that could exceed existing silica aerogel’s R-value at near standard temperature and pressure conditions and ~90% reduction of the unit price (> R15/inch with the installed unit price < $ 0.85 /ft2 wall area). The new composite is made of silica aerogel and carbon. The elemental carbon minimizes the radiative component of thermal conductivity, increases the mechanical strength of the aerogel, and makes the hydrophilic silica aerogel hydrophobic for higher moisture and fire resistance. The proposed effort addresses cost, consistency and scalability issues with the reported silica aerogel supercritical extraction approach. i) Cost: unlike aerogel preparation by supercritical drying, which is inherently expensive, the R2R printing of aqueous silica gel coupled with in-situ ambient pressure drying provides high-throughput production at near ambient conditions. ii) Consistency: the rapid prototyping additive manufacturing with shape, dimension and mounting fixture customization provides consistent quality of aerogel insulation materials for low-cost, fast, and easy installation. The highly customized insulation pieces requires almost zero post-processing (cutting, drilling, bending, rolling) effort and generates zero waste (scrap), which further reduces the labor cost and material cost. iii) Scalability: the R2R additive manufacturing and in-situ ambient pressure drying for the creation of silica aerogel, together with the carbon soot coating, will be used to directly yield silica-carbon aerogel for the rapid-prototyping synthesis under continuous operation. The cost for the synthesis and installation of silica-carbon aerogel will be significantly reduced, while also meeting existing durability requirements. Water as the earth’s most abundant clean and healthy solvent, rather than exotic or toxic chemicals, is used in the proposed process to reduce cost and environmental impact. Compared to the commercially available insulation materials, the proposed high R-value silica-carbon composite aerogel exhibits higher durability, fire resistance, water resistance and lighter weight.