Inorganic aerogels such as silica, clay, and metal oxide have been extensively studied during the last 70 years. One major disadvantage of inorganic aerogels is that they are brittle. Organic aerogels generally are more flexible, but their mechanical moduli and strengths tend to be lower. The uniqueness of the team's nanofibrillated cellulose fiber (NFC)-based organic aerogels is that with optimized material formulations and processes, they can be both flexible and strong. The specific mechanical properties of the team's polyvinyl alcohol (PVA)-NFCgraphene oxide (GO) aerogels are favorable in comparison with the specific mechanical properties of other types of aerogels reported in the literature. Furthermore, NFCs are made from sustainable and abundant biomass, thus making it a more environmentally friendly material than petroleum-based products. In addition, these NFC-based aerogels are prepared using a freeze-drying process, which uses water instead of organic solvents. Freeze-drying has the potential to allow for easy scale-up.
Aerogels have drawn significant attention due to their unusual and interesting material properties, including a high porosity (typically 90% to 99%), ultra-low density, high specific surface area, and very low thermal, acoustic, and electrical conductivities. The sustainable NFC-based aerogels the team fabricates using an environmentally friendly and scalable process in the lab have excellent flexibility and specific compressive strength, extremely low thermal conductivity and water absorption, and good thermal stability. As such, they can be used for a wide range of thermal insulation applications such as homes and buildings, industrial equipment, and clothing. This I-Corps project will help the team deepen their understanding of the aerogel density and material property relationship, which can provide a guideline, if successful, for material selections for various applications.
We have developed a family of hybrid organic aerogels based on polyvinyl alcohol (PVA)–cellulose nanofibrills (CNF)–carbon nanofillers. They offer outstanding material properties including excellent flexibility and high specific compressive strength, low density and thermal conductivity, desirable thermal stability, and excellent moisture resistance. In addition, our PVA–CNF-based aerogels are fabricated using a freeze-drying process that only involves water. In contrast, supercritical drying, the most dominant method used to produce commercially available aerogels such as silica, requires the use of organic solvents and a time-consuming solvent exchange process. Thus, these environmentally friendly and high-performance aerogels present an outstanding opportunity for commercialization. The major activities we conducted during the six-month I-Corps project revolved around customer development and the creation of a business canvas model. Although our technology could potentially be applied to a myriad of applications—including thermal insulation in building construction; outdoor gear and apparel; industrial heating, ventilation, and air-conditioning (HVAC) insulation; and hygiene; as well as in the automotive, aviation, and aerospace industries—we focused our initial efforts on finding applications within the green building industry because these aerogels can potentially solve some of the existing customers’ pain-points. We have gained a thorough understanding of the market structure, major players, influencers, and competitors in the green building industry after making contact with a number of potential customers, which helped us to further optimize the design and manufacturing processes of our hybrid aerogels. In addition, the PI hosted a female high school student in her lab during the summer of 2012 who gained rich experience in preparing and characterizing these aerogels.
