Replacing 3D printing plastics with plant-derived materials

By?Jeff Mulhollem

USDA grant to fund Penn State researchers developing new and sustainable materials from lignocellulosic biomass

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A sustainable resin material comprising agriculturally derived components could potentially replace plastics used in large-format 3D printing, which can produce furniture, boats and other similarly sized objects, according to a team of Penn State agricultural and biological engineers.

A three-year, $650,000 grant from the U.S. Department of Agriculture’s National Institute of Food and Agriculture will underwrite the team’s effort to develop a substitute for currently available expensive, highly engineered resin materials that are mixtures of petrochemically derived components.

“Our project team’s long-term goal is to develop new and sustainable bioproducts from lignocellulosic biomass — or dry plant matter — that economically enable a low-carbon bioeconomy,” said team leader?Stephen Chmely , assistant professor of agricultural and biological engineering in the?College of Agricultural Sciences . “The objective of this proposal, which is a step toward our long-term goal, is to create a renewable resin material comprised of agriculturally derived components that will enable large-format 3D printing by stereolithography.”

Stereolithography is a technique for creating?3D?objects, in which a computer-controlled moving laser beam is used to build up a required structure, layer by layer, from a liquid polymer that?hardens?on contact with laser light.

The researchers are working to develop chemical transformations of plant-derived materials lignin and nanocellulose to create renewable stereolithography resins containing these biomaterials and soybean oil. Lignin is a complex organic polymer found?in the cell walls of many plants, making them rigid and woody. Nanocellulose comprises tiny particles generally produced from?wood pulp,?though it can also be prepared from any cellulosic source of plant material.

Nanocellulose is?an “exciting class” of cellulose materials with properties and functionalities distinct from bulk cellulose and wood pulp, Chmely explained. As a result, it is being developed for applications that once were thought impossible for cellulosic materials.

According to Chmely, the team hopes to demonstrate that the new resins will display increased elasticity, toughness and thermal resistance compared to available commercial resins. The researchers will evaluate the new materials’ properties with spectroscopic and microscopic investigations, mechanical testing and thermal analysis.

The team is well positioned to conduct this research because it is part of the?Department of Agricultural and Biological Engineering ?at Penn State, Chmely pointed out, providing members with a unique perspective at the intersection of materials science and engineering with agriculture and forestry.

“Our team has abundant expertise in lignin chemistry, cellulose nanomaterials and 3D printing by stereolithography,” he said. “Collectively, these breakthroughs will have significant positive impacts on industries working in additive manufacturing and biorefining, on academic researchers working in the fields of materials science and biomass chemistry, and on rural communities that provide biomass feedstocks for these efforts as they are scaled up and deployed.”

Jeffrey Catchmark , professor of agricultural and biological engineering and bioethics, is co-principal investigator on this project.