Monday, May 20, 2024

Sustainable cool packaging alternative to Styrofoam made from recycled paper

Polystyrene, better known as Styrofoam, is used for insulation, most commonly found in packing material to keep products safe while shipping and storing “cold chain” items. This single-use Styrofoam packaging is non-biodegradable and difficult to recycle.

In order to replace the less environmentally friendly Styrofoam packaging, researchers at the Institute of Natural Products Engineering at TU Dresden have developed an insulating material made from recycled paper for shipping temperature-sensitive foods and medicines.

For this purpose, the TUD Institute experts first converted the shredded paper waste into a slurry and then, using a special drying process, produce fiber-based insulating elements from that slurry. The fiber mats have a particularly low density with a sufficiently narrow pore size distribution, and the insulating properties reach their optimum. Scientists claimed that the new material has the potential to replace conventional insulation materials such as Styrofoam due to their low thermal conductivity.

Sustainable cool packaging alternative to Styrofoam made from recycled paper
3 cm thick fiber insulation mats (left, based on paper for recycling right, based on cellulose), dry-processed, with a density of about 30 kilograms per cubic meter. Credit: TU Dresden

Due to the low thermal conductivity and higher heat storage capacity of cellulose, the insulating properties of the sustainable fiber mats even surpass those of most other materials,” said Thomas Schrinner, project coordinator at the Chair of Wood Technology and Fiber Materials Engineering.

Even though the fiber insulation elements are wrapped in a film due to potential contact to food, the fresh shipping packaging stabilized by an outer carton is already considered a “fully recyclable end product”. Schrinner explained: “At seven percent, the proportion of film in the overall system is so low that the shipping packaging can be fed into the paper for recycling cycle without hesitation. Nevertheless, film wrapping is only an interim solution.

In the next step, the researchers also want to develop sustainable alternatives, such as cellulose-based barrier layers. According to the researchers, the new insulation material has already proven itself to be a system solution for mail order. The fresh food shipping packaging is distributed by easy2cool GmbH, which tested and developed the manufacturing process for configurable insulating elements and overall packaging systems as a cooperation partner.