Abstract
We report the manufacture of printable, sustainable polymer systems to address global challenges associated with high-volume utilization of lignin, an industrial waste from biomass feedstock. By analyzing a common three-dimensional printing process—fused-deposition modeling—and correlating the printing-process features to properties of materials such as acrylonitrile-butadiene-styrene (ABS) and nylon, we devised a first-of-its-kind, high-performance class of printable renewable composites containing 40 to 60 weight % (wt %) lignin. An ABS analog made by integrating lignin into nitrile-butadiene rubber needs the presence of a styrenic polymer to avoid filament buckling during printing. However, lignin-modified nylon composites containing 40 to 60 wt % sinapyl alcohol–rich, melt-stable lignin exhibit enhanced stiffness and tensile strength at room temperature, while—unexpectedly—demonstrating a reduced viscosity in the melt. Further, incorporation of 4 to 16 wt % discontinuous carbon fibers enhances mechanical stiffness and printing speed, as the thermal conductivity of the carbon fibers facilitates heat transfer and thinning of the melt. We found that the presence of lignin and carbon fibers retards nylon crystallization, leading to low-melting imperfect crystals that allow good printability at lower temperatures without lignin degradation.
| Original language | English |
|---|---|
| Article number | eaat4967 |
| Journal | Science Advances |
| Volume | 4 |
| Issue number | 12 |
| DOIs | |
| State | Published - Dec 14 2018 |
Funding
We thank A. X. Staub and J. L. Long for assistance with the material blending. This manuscript has been authored by UT-Battelle, LLC, under contract DE-AC05-00OR22725 with the U.S. Department of Energy (DOE). The U.S. Government retains, and the publisher, by accepting the article for publication, acknowledges that the U.S. Government retains a nonexclusive, paid-up, irrevocable, worldwide license to publish or reproduce the published form of this manuscript, or allow others to do so, for U.S. Government purposes. DOE will provide public access to these results of federally sponsored research in accordance with the DOE Public Access Plan (http://energy.gov/downloads/doe-public-access-plan). The views and opinions of the authors expressed herein do not necessarily state or reflect those of the U.S. Government or any agency thereof. Neither the U.S. Government nor any agency thereof, nor any of their employees, makes any warranty, expressed or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. The research at the Oak Ridge National Laboratory, managed by UT Battelle, LLC, for the U.S. Department of Energy (DOE) under contract DE-AC05-00OR22725, was sponsored by the Office of Energy Efficiency and Renewable Energy BioEnergy Technologies Office Program. J.K.K. and K.C.L. acknowledge the financial support of the Neutron Scattering Division (NSD) of the Oak Ridge National Laboratory (ORNL), which was sponsored by the ORNL Scientific User Facilities Division, DOE Office of Basic Research Sciences. J.K.K. also acknowledges the financial support of the Center for Nanophase Materials Sciences (CNMS) of the Oak Ridge National Laboratory (ORNL), which was sponsored by the ORNL Scientific User Facilities Division, DOE Office of Basic Research Sciences.
