Dr. Neb Jaksic, Engineering 

This research investigates flow characteristics of various hemp-based composites used in 3D printing. It is an expansion to the research already in progress. While the current research is based on the goal of optimizing the hemp-plastic ratio in filament composites, this proposed research emphasizes understanding of underlying principles and it should further help in material optimization. This application seeks funding mainly for an instrument necessary for this research. We are also seeking limited funding for faculty and students compensation. In particular, the funding is requested for one rheometer, two faculty members (one from Engineering and one from Chemistry), two undergraduate students, and one graduate student.

3D printing is a prototyping and manufacturing process where molten plastic filament is extruded from a nozzle creating a layer of a 3D object. A number of these layers are fused together to create 3D objects. The process may create complicated (or personalized) objects and assemblies that cannot be created by any other manufacturing method.

To minimize the cost of filament material and to increase the strength of the created objects, different reinforcing agents can be added to the filament composite. We are studying hemp as a reinforcing agent because hemp is stronger than plastic and is less expensive. However, if the hemp particles in the filament are too large they can clog the 3D printing nozzle and therefore stop the process. This results in wasted material and time (time to clear the nozzle and time to re-print the object). If the hemp particles are too small, then the created objects are not as strong as they could be.

In addition, we are considering recyclability of 3D printed objects. Namely, the process of creating new filament by directly recycling 3D printed parts does not yield useful filament – such filament clogs 3D printers’ nozzles. This research aims to characterize hemp-based material before and after 3D printing from the “viscosity” point of view.

This research will provide the following analyses of polymers and hemp-based composites used in 3D printers: 1) Rheological analysis (viscosity) of molten (varied temperatures) filament before and after 3D printing using HempBioPlastic (HBP@), hemp-PLA, hemp-ABS, hemp-Nylon, and wood-PLA; and 2) Polymer analysis (structure and configuration) of HempBioPlastic, hemp-PLA, hemp-ABS, hemp-Nylon, and wood-PLA liquid solutions using Liquid Chromatography (LC) methods with appropriate detectors. We will verify our results by using instruments from engineering and chemistry department. We plan to submit abstracts for the ICR Conference (2019 and 2020), present our results at the ICR conference, and submit two manuscripts for the Journal of Cannabis Research (2019 and 2020).