Jason Y. C. Lim Research Group
Sustainable Supramolecular Materials Lab
Institute of Materials Research and Engineering (IMRE), A*STAR
Materials Science and Engineering, National University of Singapore (NUS)
Our Interests
Waste Plastic Upcycling
Petroleum-based are incredibly versatile materials and are ubiquitous in modern society. Some of the most common plastics in use today include polyethylenes (PEs), polypropylenes (PPs), polystyrene (PS), poly(vinyl chloride) (PVC) and poly(ethylene terephthalate) (PET). At the moment, however, they have very unsustainable and linear life cycles, with most ending up in incinerators or landfills after (single) use. Despite this, due to their diverse material properties, versatility, durability and low cost of production, it is difficult to completely replace these petroleum-based plastics with (biodegradable) alternatives in the foreseeable future.
Our research thus strives to place these abundant plastics at the start of the value chain. Where others see waste plastics as trash, we see numerous opportunities to repurpose them as feedstock for production of societally-relevant chemicals and functional polymers. The transformation of low value waste plastics to high value products is termed plastics upcycling. To achieve this, we leverage on our expertise in catalysis and materials design. Some highlights of our recent work include turning waste PET into polymer electrolytes for lithium ion batteries (JMCA, 2022) and PE into antifungal polymers (Macromolecules, 2023). By transforming plastic waste into raw materials, we aim to reduce humanity’s reliance on fossil fuels, while concurrently lowering their carbon footprint resulting from waste plastic incineration.
Sustainable Gel Materials
Gels are 3D molecular networks that entrap a large quantity of water or organic solvents, and have many functional applications. Here, we are particularly interested in temperature-responsive hydrogels (also known as thermogels) that self-assemble by non-covalent interactions between polymer molecules. These gels are liquids at low temperatures and undergo a spontaneous phase transition when warmed to form a solid-like gel. Here, we have designed new families of transparent thermogel materials that are able to act as vitreous replacement materials that facilitate post-retinal surgery recovery (Biomaterials, 2022 and Nat Commun, 2022), and even act as delivery agents in eye drops that help drugs traverse various eye barriers to achieve their intended therapeutic effects at the back of the eye (Adv Mater, 2022). A major line of current inquiry at the present is to develop hydrogels that can act as drug delivery agents in the eye.
​
Other than biomedical applications, we are also interested in developing new gel materials with sustainable applications such as polymer electrolytes for supercapacitors (ChemSusChem, 2021). We are also interested in developing new catalysts that can synthesise polymer gels under more environmentally-friendly conditions.
Novel Porous Materials
Metal organic frameworks (MOFs) are porous materials that allow unprecedented bottom-up design of their structures for targeted applications such as gas storage, separation, molecular sensing and catalysis. Here, we are interested in developing new sustainable applications of MOFs, as well as developing new MOF hybrid materials that offer new possibilities in sustainability (Green Chem, 2022) and biomedical applications (Biomater Sci, 2023).
Defect engineering is a cost-effective and practical method to improve on the functionality of MOFs without having to design new and synthetically-complicated organic linkers. This method works by rational introduction of missing linkers or metal nodes in MOF structures, which offer coordinatively-unsaturated sites that enhance interactions with guest molecules. Here, we are interested in developing new methods to introduce defects into common MOF structures that open up new possibilities in gas capture, catalysis and other sustainable applications.