Viscosity measurements carried out when heating and cooling were carried out using an Anton Paar Physica MCR301 rheometer. Measurements were performed using a 50 mm cone geometry (CP50) with gap distance between the geometry and the plate set to 0.101 mm and temperature cycled from 25 °C to 60 °C and back to 25 °C at a rate of 5°C /min. Samples were poured onto the plate to minimise shearing that would be caused by pipetting the solutions.