Kinetic Modeling of Precipitation Terpolymerization for Functional Microgels

摘要

Microgels based on poly(N-isopropylacrylamide)-and poly(N-vinylcaprolactam)can be synthesized by precipitation polymerization.To get a better insight into the kinetics of the microgel synthesis,a model-based approach is pursued.Herein,the approach proposed by Janssen et al.(2017)is extended to the terpolymerization system.The kinetic model for a two-phase terpolymerization is combined with parameter values from quantum mechanical calculations.The remaining unknown parameter values are estimated from experimental data using reaction calorime-try and Raman spectroscopy.Acceptable agreement of simulation and experimental measurements is obtained.The prediction of the gel phase growth is combined with the consumption of comonomers and the cross-1inker Af,iV’-methylenebis(acrylamide)to predict the average distribution of comonomers,thus giving insight into the microgel structure.The resulting particle structures indicate uniform/V-vinylcaprolactam and AMsopropylacrylamide compositions in the core and an outer layer with a high iV-vinylcaprolactam fraction,while the cross-1inker distribution decreases from core to shell.