The Polymer Science Group is involved in the following research areas.
From simple organic molecules to complex macromolecular architectures to functional materials; the PSG takes a bottom-up approach to prepare a range of innovative and elegant materials for the next-generation of targeted applications.
Whether designing self-assembling polymeric systems to understand and mimic the wonders of the natural world, or polymer therapeutics for improved quality of life, the PSG, in collaboration with research institutes across the globe, continuously challenges the boundaries of modern polymer science to facilitate the development of cutting-edge advanced materials.
Recent activities in the PSG have seen the development of promising implantable drug-polymer conjugate devices, nanoparticle drug delivery vehicles and glycopeptide mimics for the treatment of cancer, and infectious and neurodegenerative diseases. Furthermore, the introduction of intricately structured materials, including nanocomposites, nanolenses, highly ordered nano- and micro-porous films, and self-assembled polymers, are paving the way for exciting opportunities in advanced optics, light weight and mechanically robust composites, nanoparticle-enhanced radiotherapy, imaging and separation sciences.
Recently, the PSG successfully synthesised the first star-shaped polymer derived entirely from naturally occurring amino acid building blocks. Currently, their application to polymer therapeutics, including targeted drug delivery vehicles for cancer treatment, siRNA delivery vectors, and as anti-microbial agents is being explored. Furthermore, we have demonstrated that the functionalized peptide stars can specifically target cancer cells. Many of the naturally occurring amino acids, as well as physiologically benign non-natural amino acids, have yet to be explored as building blocks to make peptide-based architectures; application of these will undoubtedly expand the potential functionalities of the star polymers, which in turn creates a versatile platform with broad applicability. Therefore, it is evident that peptide-star polymers have a bright future beyond nanomedicine, with advances anticipated throughout the fields of tissue engineering, biocoatings, bioimaging and self-directing templating systems.
Gas Separation Membranes
The capture and storage of carbon dioxide (CO2) from coal fired power-stations has been identified as one potential solution to greenhouse gas driven climate change. Efficient separation technologies are required for the removal of carbon dioxide from flue gas streams to allow this solution to be widely implemented. Membrane technologies offer several advantages, including higher energy efficiencies that lead to more economically viable capture of CO2 relative to current approaches, such as solvent absorption. As part of the CRC for Greenhouse Gas Technologies (CO2CRC) the PSG Membrane Project focuses on three promising classes of membrane materials, namely ultra-thin film composite (UTHC), block copolymer and mixed matrix membranes (MMMs) driven by the need for increased gas separation performance, reproducibility and processability, at lower cost. The separation performance of membranes is typically limited by an upper bound trade-off between gas permeability and selectivity, which we aim to exceed through the intelligent design of novel polymeric precursors with engineered and highly organised membrane forming characteristics.
Monolayers are thin films of amphiphilic molecules, which sit at the water/air interface, formed from. They offer several advantageous properties such as self-spreading across the water surface and biodegradability, while only requiring small amounts. The Polymer Science Group has two main areas using monolayers, water evaporation control and films to reduce coral bleaching.
Water evaporation mitigation
Australia loses up to 23,000 GL of water to evaporation from reservoirs each year, equivalent to 120% of all water consumed in Australia. Monolayers are unique materials that can reduce evaporative losses by spreading out on the water surface forming an ultra-thin film, restricting the transfer of water into the air. Previous materials have had limitations due to the impact of wind and waves. Our team is addressing this challenge by developing novel materials. The final aim is the development of a superior ultra-thin film product for use by mining companies, municipal water authorities, irrigators and the agricultural industry.
Surface films to protect the Great Barrier Reef
Coral reefs provide 70,000 jobs and more than $6 billion to the Australian economy. They are also an important ecosystem with large biodiversity, containing more than 25% of marine species. Coral bleaching caused by increasing ocean temperatures due to climate change and high light intensities are considered the greatest challenge facing the survival of the reef. Our team is currently developing films that combine the self-spreading properties of monolayers with the light scattering properties of particles to help address this challenge.
Tissue defects, sustained through disease or trauma, present enormous challenges in regenerative medicine. Modern tissue engineering (TE) aims at repairing these defects through a combined approach of biodegradable scaffolds, suitable cell sources and appropriate environmental cues, such as biomolecules presented on scaffold surfaces or sustainably released from within. TE is one of the emerging research themes in the PSG. Within its new purpose built premises the PSG hosts a state-of-the-art cell and tissue culture laboratory where newly developed polymers and polymer-drug conjugates can be subjected to a range of biocompatibility tests and evaluated for their suitability as TE scaffolds or gene and drug delivery vehicles, respectively. We are currently involved in a range of interdisciplinary research projects in the tissue engineering and drug delivery space, eg: regeneration of corneal endothelium, soft tissue engineering, controlled release drug delivery platforms, and drug polymer conjugates for cancer therapy.
Continuous Assembly of Polymers (CAP)
Fabrication of precisely nanoengineered thin films is crucial for the development of the next-generation of advanced materials, including membrane purification units, electronics, biomaterials and renewable energy products. In collaboration with Frank Caruso, our group has developed a novel technique, termed Continuous Assembly of Polymers (CAP), to generate exactly such films with tailored properties at the nanoscale. The CAP process allows the single-step growth of cross-linked 3D films from initiator-functionalised surfaces via controlled polymerisation methods in an efficient and versatile manner. More importantly, the CAP process advantageously provides access to polymeric films that are difficult to achieve via conventional methods, such as those derived from naturally occurring polymers. Given the advantages of the CAP process and the promising applications that could arise from it, the group currently places a strong emphasis on CAP and is working towards the goal of developing newer and more technologically advanced materials.