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

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.

Microscopic characteristics of Janus nanoparticles prepared via a grafting-from reaction at the immiscible liquid interface

The interfacial tension, initial monomer concentration, and reaction probability can greatly influence the microscopic characteristics of the Janus nanoparticle (JNP) structure. The asymmetric initial monomer concentration in solution and the reaction probability can be used to control the syntheses of asymmetric JNPs.

Synthesis of cyclic polymers and flaws of the Jacobson–Stockmayer theory

The results of this study show that even at the highest initial monomer concentration (IMC) complete cyclization of polymer chains can be achieved at 100% conversion.