Formulation of dispersed systems via (melt) emulsification: Process design, in situ diagnostics and regulation

该项目的目标是通过熔融乳化自动化生产液-液分散系统，在此过程中，乳化在高温下进行。冷却后的产物为球形纳米颗粒或微米颗粒的分散体。在该项目的范围内，将进一步开发一种熔融乳化设备，用于自动化生产具有明确粒度分布(PSD)的产品颗粒。PSD对后续产品的性质有很大影响，如流动行为或药物释放动力学。产品的PSD是由竞争机制的复杂相互作用决定的。特别是，这些是由于剪切和拉伸应力以及合并和进一步成熟而导致的转子-定子装置中的液滴破碎，而这又取决于系统组成，即所使用的乳化剂(类型、浓度)和分散相(粘度、体积分数)。因此，为了更好地理解过程和积极控制过程，迫切需要现场测定PSD的可能性。本项目研制了一种新型的基于宽带弹性光散射的光纤耦合测量系统，用于PSD的在线测量。该系统将在参考粒子系统上进行验证，并应用于乳化过程。在此基础上，建立了混合过程模型，为模型预测控制的设计奠定了基础。模型预测控制与现场测量相结合，将为主动过程控制和生产具有预定性质的乳液提供可能性，并同时优化工艺时间。

The aim of this project is the automated production of liquid-liquid disperse systems via melt emulsification, whereby in this process emulsification takes place at elevated temperature. The products obtained after cooling are dispersions of spherical nanoparticles or microparticles. Within the scope of this project, a melt emulsification device for the automated production of product particles with a well-defined particle size distribution (PSD) will be further developed. The PSD has a significant influence on the subsequent product properties, such as flow behavior or drug release kinetics. The PSD of the products is determined by the complex interaction of competing mechanisms. These are, in particular, droplet breakup in a rotor-stator device as a result of shear and elongation stress, as well as coalescence and further ripening, which in turn depend on the system composition, i.e. the emulsifier used (type, concentration) and the dispersion phase (viscosity, volume fraction). Therefore, for a better process understanding and an active process control, possibilities for in situ determination of the PSD are urgently required. In this project, a novel fiber-coupled measurement system based on broadband elastic light scattering is developed for in situ measurement of the PSD. The system will be validated on reference particle systems and applied to the emulsification process. Furthermore, a hybrid process model is developed, which is the basis for the design of a model predictive control of the process. The model predictive control in combination with the in situ measurement will provide the possibility for an active process control and the production of emulsions with predefined properties and a simultaneous optimization of the process time.