Mathematical Modeling and Optimization of Run Parameters of Crystallization Analysis Fractionation (CRYSTAF)

Blends of a random poly(propylene) copolymer with different types of polyethylene were used to develop a sample independent statistic mathematical model which describes the quality of phase separation of polymer blends obtained by CRYSTAF. By coupling the abstract model with experimental data, process parameters influencing the non-equilibrium CRYSTAF separation process can be determined. It could be shown that the stirring speed applied during the fractionation process strongly influences the resolution of the derived CRYSTAF profile and thus the quality of fractionation. Nonlinear optimization of the models' response function leads to optimized run parameters for the CRYSTAF process which results in CRYSTAF profiles of high resolution and thus to a high quality in fractionation.