Kinetic modeling of the copolymerization of acrylic acid and trimethylolpropane triacrylate over pre and post-gelation periods

• A mathematical modeling concerning the hydrogel production through vinyl/trivinyl copolymerization was developed and validated with experimental data.
• The model is able to predict the gel evolution as well as molecular weight distribution of soluble chains during the process.
• Structural characteristics such as pendant double bonds evolution and concentration of cyclic chains can also be predicted.

A kinetic model based on method of moments, balance of species and sequences and numerical fractionation was developed for acrylic acid – TMPTA copolymerization. Solution copolymerizations of acrylic acid with trimethylolpropane triacrylate (TMPTA), initiated by sodium persulfate, were carried out at 55 °C. The model was compared with a different approach from literature and validated with experimental data from present work. It was a found an acrylic acid propagation rate coefficient at 6000 L mol−1 s−1 for the studied conditions. The simulations were successfully performed with a maximum number of generations in the range 3–5. The model was able to provide fair predictions for the studied experiments and additional information about the dead polymer chains formed, such as gel fraction, molecular weight distribution and concentration of cyclic chains.

Figure optionsDownload as PowerPoint slide