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Iron-containing imidazolium-based ionic liquids were successfully applied as catalysts in the styrene polymerization. Solventless conditions, organic solvents and different imidazolium-based ionic liquid catalysts were tested to evaluate the best reaction conditions. The ionic liquids BMI.FeCl 4 and BMI.Fe 2 Cl 7 showed very distinct catalytic activities. Schulz–Flory distributions indicate two or three active catalytic species in different distributions. Via on-line direct infusion electrospray (tandem) mass spectrometry (ESI-MS(/MS)) reaction monitoring, both active catalytic species in accordance with the Schulz–Flory distributions were intercepted and characterized, providing important mechanistic insights that allowed us to propose a rationale for the origin of the superior catalytic efficiency. [ABSTRACT FROM AUTHOR]

This work reports the use of acrylated fatty acid methyl ester (AFAME) as a biomonomer for the synthesis of bio‐based hybrid magnetic particles poly(styrene‐co‐AFAME)/γ‐Fe2O3 produced by miniemulsion polymerization. Poly(styrene‐co‐AFAME)/γ‐Fe2O3 can be tailored for use in various fields by varying the content of AFAME. The strategy employed is to encapsulate superparamagnetic iron oxide nanoparticles (SPIONs) as γ‐Fe2O3 into a styrene/AFAME‐based copolymer matrix. Raman spectroscopy is employed to ensure the formation of the SPIONs (γ‐Fe2O3) obtained by a co‐precipitation technique followed by oxidation of Fe3O4. The functionalization of SPIONs with oleic acid (OA) is carried out to increase the SPIONs–monomer affinity. The presence of OA on the surface of γ‐Fe2O3 is certified by identification of main absorption bands by fourier‐transform infrared spectroscopy (FTIR). Thermal analysis (differential thermogravimetry/differential thermo analysis and differential scanning calorimetry) results of poly(styrene‐co‐AFAME)/γ‐Fe2O3 show an increase in AFAME content leading to a lower copolymer glass transition temperature (Tg). Dynamic light scattering (DLS) measurements result in poly(styrene‐co‐AFAME)/γ‐Fe2O3 particles with diameter in the range of 100–150 nm. It is also observed by transmission electron microscopy (TEM) and cryo‐TEM techniques that γ‐Fe2O3 particles are successfully encapsulated into the poly(styrene‐co‐AFAME) matrix. The biomonomer obtained from soybean oil (AFAME) is used for the synthesis of bio‐based hybrid magnetic particles, poly(styrene‐co‐AFAME)/γ‐Fe2O3, by miniemulsion polymerization. As a principal strategy, the superparamagnetic iron oxide nanoparticles γ‐Fe2O3 are encapsulated into styrene/acrylated fatty acid methyl ester (AFAME)‐based copolymer matrix. The properties of poly(styrene‐co‐AFAME)/γ‐Fe2O3 can be modulated depending on its use by varying the amount of AFAME. [ABSTRACT FROM AUTHOR]

For the first time, it was shown the cationic miniemulsion polymerization of styrene using an ionic liquid as catalyst. The ionic liquid (BMI·Fe 2 Cl 7 ) was tolerant to the presence of high amount of water, being effective for polymerization of styrene in the evaluated temperatures range from 70 to 90 °C. The polymerization was considerably slower than conventional cationic polymerization, indicating that this process is easier to control than the conventional ones. In addition, quite high molecular weights were reached, while the particle size, between 150 and 175 nm, was within the typical range for miniemulsion polymerization. [ABSTRACT FROM AUTHOR]

The ionic liquid 1‐n‐butyl‐3‐methylimidazolium heptachlorodiferrate (BMI.Fe2Cl7) is efficiently used as catalyst in the cationic emulsion polymerization of styrene. The effect of different reaction temperatures, surfactant, and ionic liquid concentrations on polymer properties as molecular weight distribution and particle size is evaluated. High weight average molecular weights, above 1000 kDa, are achieved at 70% of conversion in 100 nm polystyrene particles formed mainly by micellar nucleation. Particle sizes and molecular weights increase with the decrease of the amount of surfactant. Even at low concentrations, BMI.Fe2Cl7/styrene molar ratio equal to 1/1000, the ionic liquid proves to be efficient for the emulsion polymerization of styrene, and lower ionic liquid concentrations lead to the formation of longer polymer chains. [ABSTRACT FROM AUTHOR]