While low-density aerogels hold promise for many industries and have a variety of uses, the science and production of them isn’t perfect. But VCU physics professor Massimo Bertino, Ph.D. is working on it.
Porous solids that are mostly air, aerogels are expensive to make — and their production can even be dangerous if not handled properly. And since most aerogels are made with petroleum, they aren’t the most environmentally friendly products, either.
Bertino, in the VCU College of Humanities and Sciences, knows aerogels’ shortcomings, but also their huge potential. So he’s developing new production processes and ways of creating aerogels that are smarter and better than current methods.
Aerogels’ low-density properties appeal to many industries, especially those in need of thermal insulation. Energy production, aerospace, batteries, ballistic protection, shock absorption, heat protection, and acoustic dampening are a few of the many fields that can benefit from aerogels.
“However, aerogels have really not been able to get a foot in the market because the processing is extremely expensive,” Bertino says.
One of the most prohibitive steps in production is a process known as supercritical drying, which pumps carbon dioxide into a high-pressure container called an autoclave. It’s a necessary step that removes the solvents, while keeping the gel properties.
“Lift that, please,” he tells a visitor to his lab in downtown Richmond. It’s a small log-sized stainless-steel container that holds the gel, rigged to a CO2 container to pipe-in gasses. It weighs 70 pounds and pressurizes solvents up to 70 atmospheres, which requires massive, heavy steel walls or else the autoclave can explode. Without the pressure, the solvents will be removed but won’t be replaced with gas, and the product will crumble and shrink.
But when properly controlled, the solvent is exchanged with carbon dioxide the aerogel’s porosity is preserved. “But it gets more expensive as greater scale is needed,” he says.
In addition to improving production methods, Bertino’s team is working on making aerogels more environmentally friendly. In lieu of oil-based gels, he’s using pectin — a component found in orange peels. He combines it with a solvent — a secret ingredient protected in his patent, for now — that, when mixed with the pectin, doesn’t require such high pressures in an autoclave in order to make an aerogel. These ,and other, “mechanically enhanced” aerogels, he says, make them suitable for a wider variety of applications.
In his lab, Bertino shows off a large Igloo cooler — the “casket,” as his team calls it, and a darkly funny story for another day. The casket allows him to dry aerogels in a normal atmospheric environment instead of the supercritical, high-pressure process. It is this process, Bertino says, that can allow for mass-production of custom-shaped aerogels, at a lower cost, and with no production hazards.
Bertino’s research and inventions have been protected by VCU Innovation Gateway, and are available for licensing.
“With both an improved production process, as well as a product that could be lower cost and environmentally friendly than traditional aerogels, Dr. Bertino has created promising technologies for industries that use aerogels as well as the producers of them,” says Brent Fagg, M.S., a senior licensing associate with Innovation Gateway. “It also really helps to have an inventor who is so passionate and excited about the potential of their research.”