PhD in Rheology of Diluted Polymer Melts

PhD Candidate in Rheology of Diluted Polymer Melts

Welcome to Maastricht University! The Circular Plastics research group at Maastricht University is looking for a highly motivated PhD candidate to join our team in developing predictive rheological insights into the processing behavior of polymer melts under dilution.

• Our goal: you will investigate how dilution affects polymer melt viscosity and develop physically grounded models that connect thermodynamics, rheology, and processing. Your work will generate fundamental insights that improve the predictability and efficiency of extrusion and recycling technologies.
• Your colleagues: you will work in the Circular Plastics team in the Faculty of Science and Engineering located at Bright lands Chemelot Campus in Geleen. You will become part of a young international research group, specialized in the mechanical recycling of plastics with a strong polymer science background. You will be guided by assistant professor Dr. Ali Gooneie and supported by other experts in the Circular Plastics group on this exciting topic.
  
  This project will be done in collaboration with Prof. Steven De Meester (Ghent University, Belgium) and Prof. Nino Grizzuti (University of Naples, Italy). You will have the opportunity to embed your work in an international collaboration.

We are seeking a motivated PhD candidate to advance the fundamental understanding of viscosity reduction in polymer–diluent systems. While the addition of low‑molecular‑weight diluents is widely used to improve processability in extrusion and recycling, current modeling approaches remain inadequate for complex, real‑world materials. At the same time, their application to thermoplastics is limited by unknown material characteristics such as molecular weight distribution, branching, and compositional heterogeneity.

This project aims to develop a physically grounded framework that links thermodynamics, rheology, and polymer processing, with a focus on understanding and modeling viscosity reduction in polyolefin‑based systems with conventional liquid diluents. You will work in close collaboration with partners to generate fundamental insights with direct relevance for extrusion and recycling technologies.

In this project, your responsibilities will entail:

• Design and perform experiments using extrusion equipment, as well as off‑line and in‑line rheometry to characterize viscosity reduction in polymer–diluent systems.
• Investigate the physical mechanisms governing viscosity reduction, with particular emphasis on the limitations of classical free‑volume theory.
• Develop and refine physically based rheological models (e.g., time–concentration superposition, thermodynamic approaches) for polymer–diluent mixtures.
• Study the influence of molecular architecture (e.g., molecular weight distribution, branching) on rheological behavior.
• Develop strategies to approximate or infer relevant material parameters of recycled polymers from experimental data.
• Extend modeling approaches to complex and multicomponent recycling streams.
• Present your work at international conferences and project meetings, and publish results in peer‑reviewed scientific journals.
• Contribute to teaching activities and supervise MSc/BSc students.

Are you ready to set the course for the years ahead? Then we’d love to meet you.

We’re not looking for check boxes; we’re interested in who you are and what you bring. Do you recognize yourself in this?

You are a self‑motivated, open‑minded and hands‑on individual with strong communication and interpersonal skills, capable of working both independently and within an interdisciplinary team, and interested in an international research environment.

Furthermore, the requisites for this position are:

• MSc degree in Chemical Engineering, Polymer Science, Materials Science, or a related field.
• Strong background in polymer rheology and physics, demonstrated for example through relevant university coursework, publications, conference presentations, and/or a thesis conducted within a recognized research group.
• Experience with experimental techniques (e.g., rheometry, extrusion) is highly desirable.
• Solid…