Sugar byproducts show promise in plastics
ST. GABRIEL, La. – Louisiana sugar producers may one day have a stake in the U.S. plastics industry, with the help of LSU AgCenter researchers.
LSU AgCenter personnel at the Audubon Sugar Institute are researching how to make plastic from a byproduct of sugar production. Aconitic acid, an organic acid that is found in significant levels in energycane, sugarcane and sweet sorghum juices, is a potential source of biodegradable plastics.
“This acid can be formulated into polyester – or plastic. It is very versatile in terms of how it can be used,” said Derek Dorman, an LSU AgCenter polymer scientist at the Audubon Sugar Institute.
Because aconitic acid can be harvested from plants, it has less environmental impact when synthesized into biodegradable polyester plastics, unlike plastics produced from crude oil. The acid is extractable from molasses, syrup or mud that is generated during the production of sugar syrups.
Researchers at Audubon are studying how to synthesize nontoxic, biodegradable polyesters from aconitic acid, cinnamic acid and glycerol – all potential products of the sugarcane and biodiesel industries – which could be used as structures for skin and bone tissue engineering.
Donal Day, a professor at the Audubon Sugar Institute, said the researchers will produce a “range of plastics” with different properties.
“We’re going to look at creating our own plastics based on materials we get by processing energycane, sugarcane and sweet sorghum,” Day said.
A variety of created polyesters will be fabricated and made into filaments for use in a 3-D printer. The printer prints acrylonitrile-butadiene-styrene copolymer 3-D models. The printing is made by heating the plastic and fusing layers together based on a template designed with 3-D computer-aided-design software.
“The proposed new filaments will be formulated to have a wide range of properties, expanding on those of traditional plastic,” Dorman said. “These plastics will be adjusted for specific properties by relatively small substitutions in the total material required. A biodegradable plastic suitable for cell cultures can be changed by adding as little as 2 percent sematic acid to produce a durable, rubbery polymer.”
Some items that have been printed using a 3-D printer include a prosthetic hand, acoustic guitar, camera lens, flute and weaving loom. On March 14, the Associated Press reported architects in the Netherlands had built an Amsterdam Canal House using a 3-D printer to “…fabricate pieces of a canal house and slotting them together like oversized Lego blocks.”
Making prosthetics “is an area we are interested in,” Dorman said. “Of course, this will be sometime in the future, but we hope to increase the available options by providing more polymeric materials with environmental concerns in mind.”
For example, he said, the process could be used to create a replacement ear.
To create a replacement ear, a matrix composed of the biodegradable polymer would be used to make the structure to grow cells, Dorman said. The 3-D printer would print the shape of an ear, and the plastic shape would be inoculated with cells to grow a normal ear.
This is just one project at the Audubon Sugar Institute. In another, researchers are studying how to use energycane and sweet sorghum to produce butanol, gasoline, isoprene and byproduct chemicals.
Researchers with the Sustainable Bioproducts Initiative are studying how to use energycane and sweet sorghum as major sources for biofuels. The AgCenter program is funded by a U.S. Department of Agriculture grant through its National Institute of Food and Agriculture AFRI-CAP program.