Master's thesis; Recycling printed flexible plastic packages by de-inking

Background
Recycling of plastic packages is an important topic to make the use of plastic more sustainable. As much as 40% of all plastic produced, is used in packages, and food packages is one of the largest markets for plastic packages.  Collection, sorting and recycling of packages is one of the best working value chains to make use of post-consumer (PC) plastic but there is still a lot to be done to increase the quality of the PC-plastic from packages.

RISE is leading a project called “Flex-Pack” together with a number of industrial project partners and the purpose is to contribute to development of the recycling value chain of printed flexible plastic packages so that high value recyclate can replace virgin raw material. The aim is closed loop recycling within the packaging industry.

Printing on packages is very important as the print conveys essential information about the product but also makes the package attractive. However, prints are one of the main sources that makes the recycled plastic dark due to pigments in the prints. An additional problem is the different binders included in the prints, as some types tends to degrade during the melt-processing of the recycled packages.

Description
This diploma work is part of the research project “Flex-Pack” at RISE, and intended to focus on the de-inking process that has the potential to remove the prints from the plastic film the packages is made up of. The subsequent recycling experiments include melt processing of the printed films and evaluation of the recycled plastic properties and this part may also be included in the diploma work. The main questions to be studied can be summarized as below:

• What are the most important parameters for an effective de-inking process?
• What types or design of prints can be de-inked, and at what conditions?
• How does de-inking influence the properties of the recycled plastic?

The diploma work will include several tasks such as literature search, develop an experimental set-up for de-inking, performing recycling experiments and characterizing the materials at different stages in the process. RISE has well equipped labs with a lot of instruments suitable for the work.

Read more about the project here: https://resource-sip.se/projekt/atervinningsbara-flexibla-plastforpackningar-med-tryck/?en

Who are you?
We are looking for a M.Sc. student in materials science, chemical engineering, or related field with a strong background in polymer science. Relevant coursework in polymer chemistry, processing, or physics is required. Interest in plastic recycling and sustainable materials is essential, as the project centers on improving recycling techniques. Lab research experience, knowledge of polymer characterization and strong data analysis are also advantageous.

Terms
Scope: 30 hp
Location: The project will be performed at RISE, in Mölndal, as part of “Flex-Pack”. 
Compensation: 10,000 SEK for travels, materials, and similar expenses after the thesis has been approved.
Start date: Januari 2025

Welcome with your application!
For questions, please contact Mattias Andersson, Senior Researcher; mattias.andersson@ri.se or 076-147 63 71. Deadline for Applications is December 1, 2024.