UMaine research to make stronger cellulose nanofibrils and use less energy while doing it

A publication by UMaine Advanced Structures & Composites Center and School of Forest Resources researchers Sungjun Hwang, Yousoo Han, and Douglas J. Gardner, in collaboration with UMaine Process Development Center researchers Colleen C. Walker and Donna Johnson, has been published in Polymers. The article titled “Spray Drying Enzyme-Treated Cellulose Nanofibrils” shares the results of using a lab-scale mass colloider to produce enzyme-treated cellulose nanofibrils (CNFs). 

The researchers found that using enzyme-treated CNFs with the mass colloider was more efficient in drying and refining the fibers, meaning that they could use less energy to produce the CNFs. Nanocellulose is extracted from cellulose, the basic component of plant cell walls. CNFs can be used to strengthen materials like plastics and in additive manufacturing (3D Printing) feedstocks as an alternative to some petroleum-based materials. By placing CNF into plastics, strong, stiff, and recyclable bio-derived material systems can be developed. 

As a bio-based material, CNF could rival the properties of steel, and its successful incorporation into plastics shows great promise for a renewable feedstock suitable for additive manufacturing. Nanocellulose is helping to build the forest products of the future.

Spray Drying Enzyme-Treated Cellulose Nanofibrils

Sungjun Hwang, Colleen C. Walker, Donna Johnson, Yousoo Han, and Douglas J. Gardner

Polymers (2023)


Enzyme-treated cellulose nanofibrils (CNFs) were produced via a lab-scale mass colloider using bleached kraft pulp (BKP) to evaluate their processability and power requirements during refining and spray-drying operations. To evaluate the energy efficiency in the CNF refining process, the net energy consumption, degree of polymerization (DP), and viscosity were determined. Less energy was consumed to attain a given fines level by using the endoglucanase enzymes. The DP and viscosity were also decreased using the enzymes. The morphological properties of the enzyme-pretreated spray-dried CNF powders (SDCNFs) were measured. Subsequently, the enzyme-pretreated SDCNFs were added to a PP matrix with MAPP as a coupling agent. The mixture was then compounded through a co-rotating twin-screw extruder to determine whether the enzyme treatment of the CNFs affects the mechanical properties of the composites. Compared to earlier studies on enhancing PMCs with SDCNF powders, this research investigates the use of enzyme-pretreated SDCNF powders. It was confirmed that the strength properties of PP increased by adding SDCNFs, and the strength properties were maintained after adding enzyme-pretreated SDCNFs.

Keywords: enzyme treatment; cellulose nanofibrils; spray-drying; polypropylene

Contact:Amy Blanchard