Nanomilling of organic compounds in stirred media mills

本研究项目的目的是深入研究有机晶体在搅拌介质球磨过程中的断裂行为。此外，还将详细研究配方和工艺参数对产品特性和研磨极限的影响。在第一个资助期的主要成果的基础上，应重点研究有机晶体介质研磨过程中同时发生的颗粒破碎、团聚、沉淀和熟化现象之间的复杂相互作用。关于溶解度对产物形成的影响以及强亲水有机化合物的络合物稳定性问题的调查是研究的一部分。此外，对有机晶体的固态和微观结构的详细表征与液相分析相结合，将对介质研磨过程中有机颗粒的产生有更深的理解。此外，应确定和详细研究影响有机颗粒研磨极限的基本机理。在第一个和第二个资助期的主要结果的基础上，将描述和优化搅拌介质粉碎机中无机材料粉碎过程的应力模型推广到有机晶体。此外，还将采取最大限度地减少研磨介质磨损的策略，以提高产品质量。因此，第二个资助期包括以下基本方面：-在介质研磨过程中区分颗粒破裂和沉淀以及熟化效应，以更深入地了解有机颗粒的机械生产。-在有机晶体湿法研磨过程中区分表面和体积效应。-表征和深入了解有机晶体、稳定剂和液体介质的复杂相互作用及其对产品特性的影响。-确定关于有机颗粒研磨极限的限制机制。-制定一项战略，最大限度地减少磨损，并表征磨损、产品颗粒和配方之间的相互作用。

Objective of this research project are in-depth investigations of the fracture behavior of organic crystals during stirred media milling. Moreover, the impact of formulation and process parameters on product characteristics and grinding limit will be investigated in detail. Building on the main results of the first funding period, the research shall be focused on the complex interplay of particle breakage, agglomeration, precipitation as well as ripening phenomena, which occur in parallel during media milling of organic crystals. Investigations concerning the influence of solubility on product formation as well as complex stability issues of the strongly hydrophic organic compounds are part of the study. Furthermore, the detailed characterization of the solid state and microstructure, respectively, of the organic crystal coupled to liquid phase analysis will gain a deeper understanding of the production of organic particles during media milling. Furthermore, fundamental mechanisms affecting the grinding limit of organic particles shall be identified and investigated in great detail. Based on the main results of the first and second funding period, the stress model for the description and optimization of grinding processes of inorganic materials in stirred media mills will be extended with regard to organic crystals. In addition, a strategy to minimize grinding media wear will be devolved to improve the product quality. Hence, the second funding period comprises the following essential aspects:- Distinction between particle fracture and precipitation as well as ripening effects during media milling to gain a deeper understanding of the mechanical production of organic particles.- Distinction between surface and volume effects during wet grinding of organic crystals.- Characterization and in-depth understanding of the complex interplay of organic crystal, stabilization additives and liquid medium as well as their impact on product characteristics.- Identification of the limiting mechanisms regarding the grinding limit of organic particles.- Development of a strategy to minimize abrasion and characterization of the interactions between wear, product particles and formulation.