Researchers in Brazil are developing a process to extract nanocellulose fibers from biomass and use those fibers to reinforce plastics. The team, led by São Paulo State University professor Alcides Leão, spoke about its research at 241st National Meeting & Exposition of the American Chemical Society March 27.

According to Leão, the fibers used to reinforce the plastics are sourced from delicate fruits like bananas and pineapples, but are extremely strong. In fact, some of these nanocellulose fibers are nearly as stiff as Kevlar. However, unlike Kevlar and other traditional plastics, nanocellulose fibers are not sourced from petroleum. Rather, they are completely renewable.

Ordinary-sized cellulose fibers extracted from wood have been used for centuries to produce paper. “In more recent years, scientists have discovered that intensive processing of wood releases ultra-small, or “nanocellulose” fibers, so tiny that 50,000 could fit inside across the width of a single strand of human hair,” said ACM in a press release announcing the research. “Like fibers made from glass, carbon, and other materials, nanocellulose fibers can be added to raw material used to make plastics, producing reinforced plastics that are stronger and more durable.” According to the presentation, these fibers—also known as nanocrystals or cellulose whiskers—are the crystalline domains of cellulosic sources.

During his presentation, Leão said that pineapple leaves and stems, rather than wood, may be the most promising source of nanocellulose. Additional plants that have shown promise include curaua, bananas, coir fibers found in coconut shells, typha, sisal fibers from the agave plant, and fique.

To extract the nanocellulose fibers from biomass, the research team placed leaves and stems from these plants into a pressure cooker-like device. After adding a proprietary mix of chemicals, the mixture is heated over several cycles. The result is a material that resembles talcum powder. While the process is described as costly, the researchers noted that only one pound of nanocellulose can be used to produce 100 pounds of super-strong, lightweight plastic. Biorefining Magazine was unable to reach a member of the research team for further details on the production process and on what scale it has been evaluated to date.

According to information released by the ACS, the properties of plastics manufactured using nanocellulose are unique. “They are light, but very strong—30 percent lighter and three to four times stronger,” said Leão in information provided by the ACS. “We believe that a lot of car parts, including dashboards, bumpers, side panels, will be made of nanosized fruit fibers in the future. For one thing, they will help reduce the weight of cars that will improve fuel economy.” Additional advantages described by Leão include greater heat resistance, and greater resistance to possible damage caused by spilled gasoline, water and oxygen. He noted that automobile manufacturers are already testing nanocellulose-reinforced plastics, and estimates they could be commercially available within two years.