Evaporative Drying of Droplets and the Formation of Micro-structured and Functional Particles

液滴的干燥是一个复杂的过程，在液相内部发生大量的动力学。这些内部过程的作用是改变干燥后形成的颗粒中材料的分布。这些工艺在从形成功能化和微结构化颗粒的喷雾干燥工艺、作物喷雾到吸入治疗期间的颗粒动力学的广泛应用中是重要的。在这个项目中，我们将探索干燥动力学的孤立液滴在空气中使用一系列独特的单颗粒实验工具。特别是，测量将使用电动平衡，直接探测的时间分辨率高达10 ms的干燥过程中的液滴的时间演变的大小和形态。稳定的平衡粘度和液滴的表面张力将询问不同的液滴组合物使用气溶胶光镊。我们将试图了解液滴如何干燥，并提供一个定量的方法来测量，预测和解释液滴蒸发的动力学。例如，我们将解决这样的问题，比如你什么时候得到一个实心粒子或空心粒子，一个均匀的粒子或一个壳？当形成时，颗粒是结晶的还是无定形的，不同的成分是混合的还是分离的？

The drying of liquid droplets is a complex process with a wealth of dynamics occurring inside the liquid phase. The effect of these internal processes is to change the distribution of materials in the particle that is formed after drying. These processes are important in a wide range of applications from spray drying processes that form functionalised and micro-structured particles, crop spraying and to the dynamics of particles during inhalation therapies. In this project we will explore the drying kinetics of isolated droplets in air using a range of unique single particle experimental tools. In particular, measurements will use an electrodynamic balance to directly probe the time-evolving size and morphology of droplets during drying with time-resolution as high as 10 ms. The steady equilibrium viscosity and surface tensions of droplets will be interrogated with varying droplet composition using aerosol optical tweezers. We will seek to understand how droplets dry and provide a quantitative approach to measure, predict and interpret the dynamics of droplet evaporation. For example, we will address questions such as when do you get a solid particle or a hollow particle, a uniform particle or one with shells? When formed, are the particles crystalline or amorphous, are different components mixed or separated?