Self-Initiated Butyl Acrylate Polymerizations in Bulk and in Solution Monitored By In-Line Techniques

Abstract

High-temperature acrylate polymerizations are technically relevant, but yet not fully understood. In particular the mechanism and the kinetics of the thermal self-initiation is a topic of current research. To obtain more detailed information the conversion dependence of the polymerization rate, rbr, is determined via in-line DSC and FT-NIR spectroscopy for reactions in bulk and in solution at temperatures ranging from 80 to 160 °C. Solution polymerizations revealed that dioxane is associated with the highest rbr, while aromatic solvents result in the lowest values of rbr. Interestingly, rbr for polymerizations in solution with dioxane depends on the actual monomer concentration at a given time in the system, but is not depending on the initial monomer concentration. The overall rate of polymerization in bulk and in solution is well represented by an equation with three or four parameters, respectively, being estimated by multiple linear regression and the temperature as additional parameter.

Kinetic Monte Carlo Simulations as a Tool for Unraveling the Impact of Solvent and Temperature on Polymer Topology for Self‐Initiated Butyl Acrylate Radical Polymerizations at High Temperatures

“…For this purpose polymerizations were carried out at temperatures up to 80°C to avoid any contributions from the unknown kinetic data at high temperatures, for example, thermal self‐initiation of the monomer or β scission are negligible up to 100°C. [ 24 ]…”

“…Previously it was shown that the overall rate of polymerization, r br , depends on the instantaneous monomer concentration in the system rather than on the starting concentration of the monomer. [ 24 ] In addition, the reaction temperature and the choice of solvent have an influence on r br . When polymerizations at different compositions of monomer and solvent at identical temperatures are monitored by in‐line FT–NIR spectroscopy, data as shown in Figure is obtained.…”

Polymerizable 2-Propionic-3-methylmaleic Anhydrides as a Macromolecular Carrier Platform for pH-Responsive Immunodrug Delivery

“…The synthesis afforded a stable 2-propionic-3-methylmaleic anhydride methacrylamide monomer characterized by NMR and electrospray ionization mass spectrometry (ESI-MS, Figures S9–S14). The use of conventional (meth)­acrylate-based monomers should be avoided, as they are more sensitive to exothermic conditions and may suffer from autopolymerization . Moreover, during base-catalyzed amidation of the anhydride, the methacrylate may also get aminolyzed, affording an irreversible ligation of the respective amine …”

Advances in continuous polymer analysis in flow with application towards biopolymers

“…In polymer chemistry, the use of flow technology is a burgeoning field with many advantages over traditional batch processes [106][107][108]. There are myriad analysis techniques which have been successfully adapted for continuous analysis of polymer systems including differential scanning calorimetry in conjunction with Fourier-transform infrared spectroscopy [109] and inline mass spectrometry [110][111][112]. Whilst these techniques clearly show promise for polymer synthesis, for biopolymers and processes which are concerned with the environmental impact of polymeric materials, molecular weight is a key parameter to analyse in a continuous fashion.…”