Bio PE a natural choice for renewable barrier coating

Stora Enso has said that bio-polyethylene is the natural choice to replace current barrier coating methods as it builds to fully renewable products.

Risto Vapola, specialist in polymer coating development, R&D and innovation, told FoodProductionDaily.com that the main material used for coating is polyethylene (PE) so the aim is to replace the fossil-based option with bio-PE.

Bio-based materials are something that will grow, adding that he hopes there will be more than one source for the material in the future, during the EU Bioplastics Conference in Berlin.

The firm work with renewable fibre-based material already but there is an opportunity for bio-based material in applications where the polymer is needed, said Vapola.

“Our target is to replace the fossil based polymers with bio-based material so that we can one day say it is 100% made from renewable materials which would give us the possibilities to market materials in a more sustainable way,” he said.

“It is coming from the fact that we are dependent on the polymers on certain applications where we need some barrier properties to paper on paperboard and also some properties for the conversion of the material, we need for example, sealability so we need the polymers to act as a barrier or function properties in combination with the paper or paperboard.”

Product example

CKB packaging board from the firm’s Skoghall Mill in Sweden was launched this year with a polyethylene coating made from renewable raw materials.

Development of the bio-coated packaging board was made possible through cooperation with the Swedish company Trioplast / Ekmans.

The first consumer products in packages coated with the laminate are fish gratin of the Norwegian fish and seafood company Domstein ASA, manufactured in Kungshamn, Sweden.

“If you think about a coffee cup for example, normal people think it’s fully paper but those are not the facts, you need a coating inside to protect the paper to be better with the coffee,” said Vapola.

“So you have a barrier against the moisture and then when you make the cup you need to seal the bottom and the side seal, so for that reason you need the polymer.

“The fibre brings you the mechanical strength and anyway the main part of the material is fibre-based even though that you have thin layers with the polymer giving the final function to the product.”

The firm said its end materials don’t have to be compostable so it is more open to find biopolymers which are bio-based.

When it comes to end of life, the first choice should be to think about recycling the material, Vapola said.

“Then of course secondly would be that if you have an application where you can utilise the compostability aspects of the material then you need this type of materials there. But the fibre-based is giving this but you also need the polymer to be fulfilling those criteria," he said.

“And thirdly, if you cannot recycle or compost the material then you at least have the possibility to create energy out from the materials by incineration. So at least landfilling is nothing we should target and it will be declining I think.”

BillerudKorsnäs stops green oil study

Meanwhile, BillerudKorsnäs has halted a pre-study on production of green oil - it was granted EU support in December 2012.

BillerudKorsnäs investigated the conditions for pyrolysis oil production from forestry residues at the Skärblacka pulp and paper mill.

The firm said its investigation showed there are technical solutions for the production of pyrolysis oil but the commercial environment at current conditions, and in the short to mid-term future development, is not solid enough.

“We are naturally not happy with having to discontinue a project that we have believed in, but the experience learned is extensive,” said Per Lindberg, CEO of BillerudKorsnäs AB.

“We will continue to monitor development in these issues and we are ready to act on business opportunities if the conditions would change.

“We remain committed to our growth agenda in our core markets and to our focus towards smarter packaging solutions.”