New hydrogels broden applications, including food production

A team of researchers in the United States has developed a process to make hydrogels with natural materials and make them useful in a host of new applications, including food and beverage manufacturing.

The new process incorporate two abundant and inexpensive basic ingredients: one is a cellulose polymer derived from natural sources such as wood chips and agricultural waste; and the other is colloidal silica, a liquid suspension of nanoscale particles derived from sand.

"When we mix the cellulose and silica together, we get a stable gel," said Eric Appel, an assistant professor of materials science at Stanford University. "By altering the formulations, we can tune across an enormous range of mechanical properties ... get a whole continuum of gel states that can be useful for different applications."

Appel led the research team and, together with doctoral candidate Anthony Yu at Stanford, described their project in the Proceedings of the National Academy of Sciences (PNAS).

Hydrogels are gelatinous amalgams of cross-linked polymers that can absorb and hold large quantities of water. However, the synthetic polymers now used for their production are often expensive or difficult to make on an industrial scale, and frequently present environmental and safety concerns.

The new process, claimed to be simple by the Stanford-led team, is expected to enable the production of hydrogels at industrial volumes, promising to break the current cost barrier.

In their paper, the authors describe testing their invention in two different applications: cleaning pipes in commercial wineries to save water as well as grape juice; and dispersing wildfire retardants, so as to coat the fuels for far longer than the standard retardant and protect the retardants from being washed away with a subsequent water treatment.

"This paper solves real-world problems," Craig Hawker, the co-director of the Materials Research Lab at the University of California, Santa Barbara, and one of the peer reviewers of the PNAS paper, was quoted as writing by a news release from Stanford. Endit