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Magnetic materials based on iron oxides are extensively designed for several biomedical applications. Heterogeneous polymerization processes are powerful tools for the production of tailored micro-sized and nanosized magneto-polymeric particles. Although several polymerization processes have been adopted along the years, suspension, emulsion and miniemulsion systems deserve special attention due to its ability to produce spherical polymer particles containing magnetic nanoparticles homogeneously dispersed into the polymer thermoplastic matrices. The main objective of this paper is to review the main methods of synthesis of iron-based magnetic nanoparticles and to illustrate how typical polymerization processes in different dispersion medium can be successfully used to produce engineered magnetic core-shell structures. It is exemplified the use of suspension, emulsion and miniemulsion polymerization processes in order to support experimental methodologies required for the production of magnetic polymer particles intended for biomedical applications such as intravascular embolization treatments, drug delivery systems and hyperthermia treatment.

The iron‐containing imidazolium‐based ionic liquids (ILs) 1‐n‐butyl‐3‐methylimidazolium heptachlorodiferrate (BMI.Fe2Cl7) and 1‐n‐butyl‐3‐methylimidazolium tetrachloroferrate (BMI.FeCl4) are applied as catalysts in the homogeneous polymerization of n‐butyl vinyl ether. Both solventless conditions as well as using different organic solvents, catalyst concentrations, temperatures, and reaction times are tested to assess the polymerization conditions that lead to the highest molecular weights of poly(n‐butyl vinyl ether). The Lewis acidic IL BMI.Fe2Cl7 proves to be highly efficient, even at low catalyst concentrations. In bulk polymerization, polymers with 142 kg mol−1 are obtained using a 1:10000 molar ratio of catalyst to monomer. In solution polymerization, the monomer consumption is also rapid and the molecular weight of the polymer is related to the catalyst concentration used. These results indicate the potential of this catalyst for industrial applications. In contrast with the acidic IL, the neutral iron‐containing imidazolium‐based IL BMI.FeCl4 does not show any catalytic activity. [ABSTRACT FROM AUTHOR]

Gas phase copolymerizations of ethylene and an α‐olefin comonomer are performed using a commercial Ziegler–Natta catalyst in the presence of different induced condensing agents (ICA). The impact of these factors on the yield and final polyethylene properties such as the melt flow index, crystallinity, and incorporation of comonomer is studied. It has been shown that the increase in the rate of polymerization is even more pronounced in the presence of ICA. It also appears that adding ICA to the copolymerizations changes the comonomer incorporation with respect to similar copolymerizations performed without ICA due to competing cosolubility effects. [ABSTRACT FROM AUTHOR]

The article presents a study which performed the dynamic optimization of semi-batch vinyl acetate (VAc)/acrylic acid (AA) suspension copolymerizations using a direct search Complex algorithm. It provides a workflow showing the proposed optimization for acrylic feed rate policies. It also details the steps of the proposed kinetic mechanism and nomenclature used in the study. It concludes that the optimization strategy can be utilized for design of monomer feed rate profiles and removal of disturbances during copolymerizations.