Modeling and predicting of nucleation efficiency based on matching lattice dimensions in isotactic polypropylene

• Direct correlation between nucleating efficiency and structural matching of additive materials • Prediction and modeling of nucleating efficiency based on lattice parameters of crystalline materials. This work reports a quantitative correlation based on the general epitaxial crystallization model between the lattice dimensions and nucleating efficiency of additive materials in isotactic polypropylene. The strong correlation is used to build an empirical model, which can predict the possible nucleation efficiency of a material with known crystalline lattice dimensions in isotactic polypropylene. The efficiency of the nucleation is characterized by differential scanning calorimetry (DSC). The crystalline lattice dimensions were collected from existing databases. The matching dimensions in different directions are handled as independent parameters and the prediction model is built up by nonlinear regression analysis on the correlation between the dimensional parameters and the nucleation efficiency. The results clearly indicate that a strong correlation exists between the dimensional matching and nucleating efficiency of the additives, and the prediction of efficiency can also be done with good accuracy. The prediction's reliability was tested using earlier data on β-nucleated iPP, and good agreement was observed between the measured and predicted efficiencies. In addition, the validation results gave a good explanation of the non-selective dual nucleation effect of β-nucleating agents. Accordingly, this type of modeling can be very useful in the development of nucleating agents for crystalline polymers.