Self-Assembled Functional Materials
We work on the synthesis and study of self-assembly of small organic molecules in to supramolecular functional materials. These range from conductive materials, chromic materials and viscosurgical ophthalmic devices. We use a range of techniques on different length scales to monitor and understand the self-assembly process such as rheology, electrochemistry, small angled neutron scattering (SANS), imaging techniques (SEM, TEM, confocal, cross-polarised light microscopy), FTIR, UV-vis spectroscopy, fluorescence spectroscopy, NMR etc. By trying to understand this self-assembly process we can not only fully characterise our materials but manipulate this process we get a range of interesting properties.
One function we are looking into is conductive materials. We have focused a lot on the assembly of perylene bisimides in water into worm-like micelles, we are looking at improving the conductivity and responsive behaviour from the materials. This can be done by the alignment of the worm-like micelles, we look at using shear and magnetic field to promote this alignment and drying them down to produce and an aligned thin film. This alignment improves the flexibility of the materials and also gives directionality in the current, all improving the devices for applications such as wearable electronics. We can also improve the lifetime of current created by using additives in the system.
Chromic materials can be used in visual displays for aesthetics or in sensing applications depending on which stimulus they are sensitive to. We are looking at self-assembled materials that change colour upon irradiating with light, change in current and other stimulus. These materials can be responsive to one or many of these stimuli and can switch between different coloured states. The coloured produced can be tuned by changing the molecule or changing the aggregation of the molecules used. These materials are being developed to be used in smart glass applications and as sensors for UV light, or in molecule detection as well as in flexible displays.
Ophthalmic Viscosurgical Devices
We work closely with Hyaltech Ltd. on developing new viscosurgical devices to be used in applications such as cataracts surgeries. This work involves improving the production and analysis of the materials but also design and fabrication of new materials with extra functionality.
Temperature Stable Materials
For all devices the working temperature is crucial to the applications. As the use of these self-assembled widens into many diverse applications, so must the environments in which these materials are able to work in must too. We have been working on developing materials that are stable to low temperature working environments, from 45 °C down to -40 °C where the mechanical properties do not change whether held at the different temperatures or cycles between these temperatures. This can be done using certain types of low molecular weight gels or the addition of glycerol into the gel systems. This opened up the possibility of using these gels in low temperatures applications such as outside, or could be used in cryopreservation or the transport of biomaterials such as enzymes.