Can wood replace plastic?

Biomass expert Emma Master is counting on the power of enzymes

This article is being created using a keyboard that is made up mostly of the material that revolutionized manufacturing when it was invented in the mid 1800s—plastic.

The problem with plastic, however, is that it is made from petroleum. We’re running out of petroleum. Besides, the actual manufacturing process that creates plastic is harmful to the environment.

But Emma Master believes she will one day be able to replace the plastic that makes up this keyboard with wood fibre. That’s right—wood or other material that comes from plants. The general term is biomass—“The structural stuff that living systems build,” says Master.

Master, assistant professor in Chemical Engineering and Applied Chemistry (and cross-appointed in Cell and Systems Biology), is working with a cadre of engineers, biologists, and physical scientists at U of T in a unique-in-Canada biotechnology research centre called BioZone.

Funded by the Canada Foundation for Innovation, BioZone brings together biotech research programs that are addressing the urgent challenges in sustainable energy and environmental protection.

“My motivation is to harness the diversity and complexity of natural materials,” says Master. “My colleagues and I believe that biological systems synthesize some of the most ornate materials. If we are going to live in a world that doesn’t rely on petroleum and fossil fuel, biomass will be crucial. It’s a wonderful material that we have primarily used only coarsely thus far, but has so much more potential.”

Master’s chief tool in harnessing biomass is another invention of nature—the enzyme.

Simply put, enzymes make things happen. Scientists call them catalysts—proteins that create chemical reactions. When you swallow food, enzymes help you digest it. They are also at the centre of making apples turn brown when they are exposed to air. “We all have enzymes in our cells that help us operate as living beings,” says Master.

Her enzyme research program has three prongs—enzyme discovery, engineering, and application development.

One of her research activities involves changing plant fibres’ ability to repel water. “If we are going to replace plastic with plant fibre, we have to match the plant’s ability to repel water with that of plastic, which handles this quite well.” To do that, they are increasing what is called the ‘surface hydropho-bicity’ of the fibre. And to do that, Master’s research team is linking water-repelling chemicals onto the surface of the fibre using enzymes as catalysts.

Another project has Master’s team working with scientists from the Alberta Research Council in taking fibres from wood, using enzymes to make them very smooth through a polishing process to generate what’s called ‘nanocrystalline cellulose’, which can be used in a broad range of products including liquid crystal displays—better known as the LCDs used in your flat screen TV or digital clock.

Master, who is also a member of U of T’s Pulp and Paper Research Centre, believes firmly in the potential for greater uses for wood fibre.

“In addition to the environmental benefits that we can realize by using wood fibre to replace petrochemicals, there is an economic motivation too. It is increasingly difficult for Canadian forest companies to compete in conventional pulp and paper markets, and so it is necessary to start harnessing higher value from this rich natural resource. Other northern countries, including Sweden, have already recognized this. My hope is that through research innovation, Canada will lead in the development of novel, renewable forest products, which will benefit Canadian communities as well as the environment.”