"When making MFC, cellulose fibres are disintegrated into their components, fibrils," Head of R&D and Innovation at Stora Enso Jan Lif says. "The fibrils are very small and invisible to the naked eye. Whereas a cellulose fibre is 1–3 mm long, the length of a fibril ranges from a few to several hundred micrometres," he explains.
What are the properties of MFC that differentiates it from traditional pulp?
Compared to traditional pulp which is white and resembles snow, MFC is transparent and looks like gel. "MFC is currently being tested in some of our packaging and media products, and in the future it has the potential to be used in a variety of entirely new products. MFC can also be used as a substitute for nonrenewable materials such as plastics, metals and chemicals. For us it creates a range of new opportunities."
Revolution in a milk carton?
"With MFC, you can make a more durable, lighter, high-quality packaging product out of less raw material, more efficiently," says Lif.
Material efficiency means the degree to which one is capable of producing a given amount of product out of a given amount of raw material. According to the European Commission and the OECD, resource efficiency is crucial in a world with a growing population and restricted material resources.
In the packaging business, the development of material efficiency has been phenomenal. To make a milk carton in the 1970s, you needed more than double the amount of raw material you do today. Now with MFC, the resource efficiency of packaging is taking another big leap.
You could call it a revolution inside a milk carton. But the shrinking amount of raw material in the carton is unnoticeable for consumers. "This is very important. You are getting more with less, but it does not compromise the quality – it only enhances it," Jan Lif says.
Rubber tyres and muffins
In addition to its packaging potential, MFC has brought along other completely new opportunities.
Rubber products are one interesting option, especially the tire industry, where you could reduce the weight of products using MFC. Replacing non-renewable materials and reducing the use of chemicals and synthetic material consumption is another big opportunity. One natural possibility would be to use MFC as a renewable coating material in food packaging.
Some possible applications are way beyond the traditional range of fibre-based products: It could be added in bakery products, such as breads or muffins to add fluffiness and to keep the product moist. Or the product could be used in some other industrial areas which have not even thought of yet.
Pilot-scale production of Micro Fibrillated Cellulose (MFC) started in late 2011 at our Imatra Mills in Finland.