Determination of Reactivity Ratios from Binary Copolymerization Using the k-Nearest Neighbor Non-Parametric...

Area of Science:

• Polymer Chemistry
• Chemical Engineering
• Materials Science

Background:

• Monomer reactivity ratios are crucial for predicting copolymer composition.
• Accurate determination of reactivity ratios is essential for controlling copolymer properties.
• Existing methods for calculating reactivity ratios have limitations, especially at higher conversions.

Purpose of the Study:

• To develop a new, robust method for calculating monomer reactivity ratios in binary copolymerization.
• To validate the proposed method using simulated and experimental data across a wide range of conversions.
• To compare the performance of the new method against established techniques.

Main Methods:

• A novel calculation method based on the terminal model for binary copolymerization.
• Utilizes a numerical integration algorithm coupled with k-nearest neighbour non-parametric regression for optimization.
• Tested on simulated data and experimental datasets for low, medium, and high conversions.

Main Results:

• The proposed method yields reactivity ratios in good agreement with traditional methods (e.g., Fineman-Ross, Kelen-Tüdös).
• Effective application demonstrated across low (<10%), medium (10-35%), and high (>40%) conversion ranges.
• Successful estimation of experimental errors from single datasets is also shown.

Conclusions:

• The new method provides accurate monomer reactivity ratios for binary copolymerization.
• It offers a reliable alternative to existing methods, particularly across different conversion extents.
• The method's ability to estimate experimental errors enhances its practical utility.