(421e) Advanced Manufacturing with Cellulosics; Rheological Considerations and Unique Applications

As the demand for sustainable materials increases, cellulose-derived materials have gained strong attention in composite systems as renewable reinforcements. Cellulose is the most abundant biorenewable polymer on earth, derived from the cell walls of many different biological sources. Cellulose and its derivatives, including cellulose nanocrystals (CNCs) and cellulose nanofibrils (CNFs) offer significant promise for a broad variety of applications, including in developing advanced stimuli responsive materials and structures. Processing such materials through additive manufacturing (AM), otherwise known as 3D printing, has gained significant attention in recent years and offers a unique approach for generated complex structures and graded architectures.

In this talk, I will highlight the importance of rheological considerations for processing cellulose-based and -reinforced composites using material extrusion additive manufacturing. Whether used in an aqueous or solvent based suspension or as a reinforcing filler in a polymeric matrix, the unique properties of cellulosics present interesting rheological challenges associated with development of formulations suitable for the different modes of AM. However, these same properties also offer the most exciting opportunities to develop voxel based, preferentially aligned and compositionally/functionally graded structures. Development of formulations for 3D printing with cellulose derivatives, including hydroxypropyl cellulose (HPC), carboxymethylcellulose (CMC), CNCs and CNFs, will be highlighted in the context of advanced material applications, ranging from load bearing composites to stimuli responsive and shape memory behavior. In addition to tailoring rheology in formulation development for successful AM, concerns surrounding shear and thermal induced degradation of the cellulosics in processing will also be addressed. The approaches highlighted here help to establish a framework for exploring the potential application of sustainable cellulose containing polymer composites in various applications.