Flagship sustainable by design circular composite bioplastics
The Wetsus research theme Biopolymers from Water develops and innovates on methods to produce and recover biopolymers, in particular polyhydroxyalkanoates (PHAs). PHAs are renewable resources that serve as a versatile platform for bioplastics within circular economy systems, with wastewater and organic residual streams as feedstocks. PHA-based bioplastics are inherently biobased and biodegradable for the plastics industry, as well as being recyclable and renewable. Through well-controlled microbial processes, PHA-rich biomass can be efficiently generated and the polymers effectively recovered, enabling circular resource use. However, such biobased plastics are still costly to produce. One strategy to enhance recovered PHAs into high-value renewable products for industry is to make biobased composite materials to maximize performance with lower cost to deliver on commercial quality standards – controlled property specifications and materials that are safe and sustainable by design. The entry of ‘waste’ derived PHAs into circular economic supply chains therefore critically depends on methods to systematically control property specifications and material costs alongside ensuring sufficiently low levels of regulated non-intended added substances (NIAS, i.e. impurities) in the recovered product.
Research challenges
The research challenge is to establish tools to predict and control property specifications of cellulose composites with co-polymer blends of poly(3-hydroxybutyrate-co-3-hydroxyvalerate). There is an expected window of batch-to-batch variability in the recovered PHA thermophysical properties and a requirement to monitor for fate of trace contaminants that must be maintained below regulated thresholds in the final product. Further there is opportunity to efficiently formulate high performance composite bioplastics directly in the PHA recovery process. Current methods do not adequately link a variability in the polymer production to the opportunity to directly tune and formulate bioplastics and composites in one step. In this project high quality cellulose will be produced from industrial flagship recycling of absorbent hygiene products, and PHA will be produced in a sister flagship industrial scale facility. Optimized composite bioplastic formulation strategies are to be developed and scaled up in collaborative activities of product prototyping. Tools for steering the composite property specifications through applied polymer science and the impurity quality control through engineering principles and strategic monitoring are to be advanced towards supporting a real-world context that demonstrates a circular economy where waste becomes a resource.
Your assignment
The research is inherently interdisciplinary with emphasis on polymer science, melt processing, propertytesting, and chemical engineering. Your work will focus on the formulation of co-polymer blends and cellulose composites thereof towards the definition of masterbatch bioplastic property specifications. You will build on established in-house and knowledge centre expertise, methods and protocols, including solution formulation, extrusion and mechanical testing, as well as analyses and protocols such as rheology, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), pyrolysis GC–MS, Fourier transform infrared (FTIR) spectroscopy, high-performance liquid chromatography (HPLC), liquid chromatography–mass spectrometry (LC-MS) and gas chromatography–mass spectrometry (GC-MS). In addition, the project entails hands-on research of PHA recovery both at laboratory and pilot-scales.
This project is part of the newly funded EU project SOWISE+, and you will therefore contribute to key research activities and work closely with our local Dutch and international partners.
Your profile
You hold a master’s degree in chemical engineering, polymer science, or a closely related field, and have demonstrated experience with practical testing in materials science, polymer melt processing, data analysis, modelling and polymer quality characterisation techniques. You have affinity, and interest, in analytical method development, and you enjoy hands-on experimental work. You have a strong self-drive with initiative to explore topics beyond your current expertise, and you are comfortable in multidisciplinary, international, collaborative settings. You are well versed and curious about concepts of structure-property relationships in polymer science, separation techniques in chemical engineering processes, and the use of ‘green’ organic solvents. Written and oral communication proficiency in English is expected.
Keywords: biopolymer blends; structure-property relationships; crystallization; melt-processing; mechanical testing; impurity tracking; analytical tools; production quality control;
Supervisory Team:
Wetsus supervisor(s): dr. Alan Werker (Biopolymers from water theme leader, Wetsus); dr. Carlos Contreras Davila (Scientific project manager, Wetsus).
University supervisor(s): Prof. Katja Loos, Faculty of Science and Engineering, Macromolecular Chemistry and New Polymeric Materials, University of Groningen.
Project partners: Biopolymers from Water
Only applications that are complete, in English, and submitted via the application webpage before the deadline will be considered eligible.
Guidelines for applicants: https://phdpositionswetsus.eu/guide-for-applicants/
