A unique manufacturing method for reinforcing paper packaging could mean new opportunities for the forestry industry. Researchers at Mid Sweden University’s FSCN research center have succeeded in devising a stronger, more moisture-resistant paper, with reduced energy consumption as an added bonus. It is now hoped that this paper can soon replace plastic in several areas.
Moisture-resistant paper bags
The method was discovered somewhat by chance during another research project, also dealing with mechanical pulp. “We tried to make the central cardboard layer as bulky and rigid as possible, and then noticed that if we tried to achieve high density instead, pressing the sheets together at a high temperature, we could also attain good strength and durability. We then proceeded in the same way.” Manufacturing large volumes of paper bags using energy-efficient mechanical pulp would also bring environmental benefits. If paper bags were to replace their plastic equivalents, we could more easily meet the EU directive which stipulates an 80 percent reduction in the use of plastic bags among EU nations up to 2025. However, in order for such a shift to be possible, the paper must first become more moisture-resistant. “One advantage of plastic bags and other plastic packaging is moisture-resistance. The majority of paper packaging cannot be used when moisture levels are high, but this paper is different. We think it can replace plastic in several areas in the future,” adds Pettersson.
Collaboration with industry
Before long, researchers at FSCN hope to be able to test the method on a large scale in factory conditions. The Knowledge Foundation, the Swedish Energy Agency, the ÅForsk Foundation, and the Nils and Dorthi Troëdsson Foundation research fund have contributed financing, while from trade and industry, SCA, Stora Enso and Holmen, among others, are working with FSCN. “All three companies have declining newsprint sales and are interested in new products. They’ve been a real help. Partnerships make our research group stronger, and support from industry means we can achieve even better results. We also got much support from MoRe Research in Örnsköldsvik, where we borrowed the pilot plant for laboratory tests,” Pettersson says.