PTS and mujo
Alginate-based packaging films

06.10.2021 Due to legislative restrictions such as the EU's Single-Use Plastics Directive (SUPD) and the trend towards the development of new, bio-economic packaging, natural polymers are increasingly coming to the fore as forward-looking alternatives to conventional fossil plastics. One of these polymers is alginic acid or alginate, which can be extracted from brown algae.

Alginate is obtained from brown algae and can be processed into transparent films (from left to right).
© Photo: PTS
Alginate is obtained from brown algae and can be processed into transparent films (from left to right).

This element of the cell walls, which gives structure to the algae, is able to form flexible and at the same time strong films – even without chemical derivatisation. It can therefore take on different tasks in paper packaging. Depending on the formulation and material thickness, barrier coatings on paper are just as conceivable as free-standing films that can be used, for example, as viewing windows in cardboard packaging. At the same time, they are fully SUPD-compliant.

Development cooperation with Berlin start-up

In order to advance the use of this exciting material in the packaging sector, PTS in Heidenau, Germany, is starting a joint development cooperation with the Berlin start-up company mujō. The aim of the work will be to develop packaging products such as films or coated papers with the help of the natural polymer alginate, which is obtained from brown algae.

"mujō has set itself the task of developing recyclable packaging materials that can be disposed of in the existing disposal infrastructure and do not pose a danger to nature and humans even in the event of incorrect disposal. We are initially focusing on water-soluble and water-insoluble transparent alginate films as well as alginate-coated barrier papers," says mujō co-founder Annekathrin Grüneberg. To make this a reality, PTS is providing its expertise and technical centre infrastructure as a development partner. In addition to developing formulations and manufacturing the materials using process technology, the work also focuses on issues such as sealability, barrier optimisation and recyclability.

Packaging made of natural polymers meets the spirit of the times

"The development of packaging components made of natural polymers complementary to paper meets the spirit of the times," says PTS business unit manager Dr Martin Zahel. "We are therefore proud to be able to support mujō, a young company with an innovative idea, on its way."

PTS is a leading German research and development institute in the paper value chain that supports companies in the development of products and materials.