Cellulose nanocrystals

Not your average wood product

Nanocrystalline cellulose (NCC) technology

NCC is cellulose in crystalline form, which is extracted from woody biomass, and processed into a solid flake, liquid and gel forms. Several key features such as high strength, electro-magnetic response and a large surface area provide a basis for the manufacture of new and advanced materials using nanotechnology.

Through FPInnovations, the federal government is partnering with Quebec and Domtar to develop and commercialize NCC technology. The $32.4 million Transformative Technologies Pilot-scale Demonstration project will support a new facility at the Domtar pulp and paper mill in Windsor, Quebec.

The pilot plant will produce one tonne of NCC per day to make specialized coatings and advanced materials out of hardwood chips. The new facility will be the first of this scale in the world—a landmark in creating renewable industrial and consumer products from forest biomass.

The Transformative Technologies Program (TTP), led by FPInnovations, Canada’s national forest research institute, explores innovative uses for wood.

One of the program’s most exciting research avenues involves developing new materials from cellulose, the main component of the cell walls of trees and other plants. In its almost-pure form, cellulose has a tiny crystalline molecular structure. Known as nanocrystalline cellulose, or NCC, this substance has intriguing properties and uses.

Possible uses of NCC

NCC increases the strength and stiffness of materials it’s added to. Just a small amount can increase resistance to stress threefold, making it attractive as a high-performance reinforcing material.

NCC can also alter the surface of material like paper, changing its permeability, strength, flexibility and optical properties. Adding a little NCC to paper noticeably boosts its gloss. NCC also improves tensile strength, stiffness, surface smoothness and bulk, paving the way for new types of paper with novel applications and for paints, varnishes and advanced high-strength materials.

Films made of NCC appear iridescent, making them an ideal decorative treatment for papers. Optical films enhanced with NCC are well suited for use in specialty packaging, biosensors and security devices; they could even help prevent counterfeiting.

In addition, because NCC is affected by magnetic and electrical fields, it could prove useful as a filler in magnetic paper, electronic memory cards and readers, and other electronic products.

Moving ahead with NCC

FPInnovations has been studying this fascinating substance for more than two years (supported by the TTP) and has come up with a process to make NCC in several forms: powder, gel, suspension, filament and film. In fact, FPInnovations has become a world leader in producing NCC on a large laboratory scale, now that its research team has developed ways to extract the material from wood pulp (see text box). This is an important breakthrough because it makes NCC usable in commercial applications.

Once the production process is piloted and NCC is more widely available, the door may open to many applications beyond pulp and paper. The aerospace and automotive industries are just two groups interested in NCC as an ingredient for lightweight, high-strength composite materials. The health products and food sectors also plan to investigate its uses.

One thing that makes NCC so appealing for the 21st century is its potentially high “green quotient.” NCC is the product of renewable, recyclable natural resources—pulp is the main source material—and testing to date suggests that it’s virtually non-toxic and its production poses no serious environmental risks.

There’s still much to learn about NCC, and researchers at FPInnovations will be studying the product for some time to come. But there’s little question that these minute crystals are poised to take the wood market in some unusual new directions.