Why?
In our everyday lives, we continuously interact with food products. Tetra Pak revolutionized the way food is protected from damaging and external contaminations; their packaging allows easily spoiled products, such as milk, to be stored for many months in a completely aseptic environment.
Nowadays we are called to make a new revolution, that is moving to a more environmentally sustainable production. The aim is to replace packaging containing fossil-based plastic with biobased alternatives. Cellulose, which is the world’s most abundant biobased and biodegradable polymer, could represent an alternative to unsustainable fossil-based plastic.
Melt processing is a sustainable and solvent-free method used to produce plastic packaging in 3D shapes. Cellulose-based packaging production has a major drawback as cellulose isn’t a thermoplastic polymer, limiting the possibility of producing it by melt processing methods. A possible solution is to perform a chemical modification of cellulose to DiAlcohol Cellulose (DAC, Figure 1), which has been demonstrated to own a temperature window in which it is melt processable.
ProDAC research project (Processing of DiAlcohol Cellulose) aims to investigate the dialcohol cellulose melt processability, the material’s properties before and after the processing and the possibility of performing chemical reactions to improve some physical properties, e.g. water sensitivity.
Aim and objective:
Dialcohol cellulose has been demonstrated to be easily melt processed using water. Water is a green plasticizer and can partially evaporate during melt compounding, however, its evaporation is energy-demanding and can also occur at room conditions, leading to materials ageing. The objective of this thesis work (30 points) is to test different biobased plasticizers that enable effective production of the materials and to study the effect of the plasticizers used on the final properties of the materials.
Methodology:
The focus of the project will be to investigate:
- melt processability of DAC (extrusion and injection moulding, Figure 2) with different plasticizers.
- physical-chemical and rheological properties of the materials by different characterization techniques.
Prerequisites
The candidate should possess knowledge of the chemistry, polymer melt processing and physical properties of polymeric materials. Knowledge in melt rheology would be advantageous.
Project start:
January 2024 or according to agreement.
Contact details:
Supervisors:
Katarina Jonasson, Katarina.Jonasson@tetrapak.com
Associate Prof. Giada Lo Re, giadal@chalmers.se
Enrica Pellegrino, enricap@chalmers.se
