Shear-Based Method for Producing High Strength Flat, Uniaxially Oriented Free-Standing Wood-Based Cellulose Nanocrystal Films

Cellulose nanocrystals (CNCs) are the primary structural unit for plant life. The most common sources for CNCs include extraction from wood, cotton, sisal, and ramie. With the potential of CNCs being inexpensive and renewable, as well as their exceptional mechanical properties, their use as a reinforcement phase in polymer-based composites has been a popular topic of recent research. The mechanical properties of individual CNCs are difficult to measure directly but, for perfect crystals, their axial elastic modulus has been estimated at 124 to 173 GPa and tensile strengths at 7.5 GPa. This surpasses common commodities of glass, brass, and Kevlar, while being virtually optically transparent.

Researchers at Purdue University have developed high-strength CNC materials, primarily films, for potential use, initially, in defense and sporting applications. There is subsequent potential use in automotive and transportation applications and packaging and shipping materials. The materials feature steel-like strength and a fivefold increase in stiffness over other polymers, while the low density of nanocellulose allows for significant weight reduction in armors. In addition to being renewable, these materials can be produced entirely through domestic means, aligning with the United States Strategic Defense Initiative.

Advantages:

-High strength coupled with low weight

-Renewable materials

Potential Applications:

-Manufacturing

-Materials

TRL: 6

Intellectual Property:

Keywords: Cellulose nanocrystals, CNCs, high-strength CNC materials, nanocellulose, polymer-based composites, reinforcement phase, defense applications, sporting applications, automotive applications, transportation applications, packaging materials, shipping materials, renewable materials, low density, high strength, steel-like strength, elastic modulus, tensile strengths, Materials and Manufacturing, Nanocrystals