Parameters for predicting the composition of nanocrystalline triglycerides under different processing conditions

点击翻译按钮获取中文摘要

This research program arises from industry's necessity to tailor, by thermo-mechanical processing, the physical functionality of lipid materials, given restrictions (nutrition, health, availability, price) imposed on the formulation. A valuable fundamental and general knowledge on the materials science of these medium sized molecules must be developed to contribute significantly to our ability to control their crystallization. The long term objective of this research program is thus the development of predictive models that determine the self-assembly of lipid multicomponent materials under the fields imposed during processing. The conceptual and mathematical models needed include crystalline nucleation and growth (composition and rate) along with momentum, heat and mass transfer mechanisms. The imposed fields include chiefly temperature profiles and shear/extensional flow under which these materials spontaneously form nanoplatelets. The development of measuring tools for the properties and performance is another essential part of the research program. The cycle of optimization of the models will be continued by comparing its predictions with the measured outcomes of controlled process. This may seem obvious, but most of the important parameters for these models cannot be directly measured. To determine them a large collection of data is necessary, and the model parameters need to be fit to correspond to the data. The implementation is not trivial, as will become apparent in this proposal. The specific objectives for this proposal aim at obtaining values for key parameters of the recently proposed linear kinetic segregation (LKS) crystallization model. In the process, the model itself will be tested. Preliminary work conducted by us has showed both the promising value of this approach, as well as many of the difficulties that are expected. The parameters are the excess energies or the solid solution and the kinetic ratio of adsorption. They depend on the polymorphic form of the nanocrystals, but are thought to be independent of the crystallization conditions.