2-Hydroxyethyl methacrylate (HEMA)-rich latex is synthesized via a semibatch monomer-starved emulsion polymerization process. Six emulsion polymerizations, containing 0-40 mol% HEMA in monomer composition, are synthesized and compared. Calculations of mass balances are made in order to predict fi nal particle size and particle size development during the course of polymerization. Average particle sizes obtained by dynamic light scattering (DLS) are compared to ultrasound acoustic attenuation spectroscopy (UAAS) and transmission electron microscopy (TEM). The infl uence of HEMA on polymerization on the onset of secondary nucleation is evaluated using each technique. The DLS, TEM, and UAAS secondary nucleation data are compared to physical latex blends of small and large particles. The blend data are consistent with the secondary nucleation data. Additionally, conductivity and surface tension are monitored. TEM, atomic force microscope (AFM), and UAAS are found to be more appropriate methods than the widely used DLS for particle size and particle size distribution characterization in this system. Increasing HEMA content to 20 mol% results in formation of signifi cant amount of secondary particles via proposed homogeneous nucleation of HEMA-rich oligomers.

Semibatch, power feed, and shot‐addition feeding strategies were employed to synthesize carboxylated latex under acidic conditions, using emulsion polymerization. As a source of carboxyl groups, acrylic (AA) or methacrylic acid (MAA) was used. The distribution of carboxyl groups between feeding strategies were investigated using rheology, potentiometric/conductometric titrations, transmission electron microscopy, and FT‐IR spectroscopy. Upon alkalization, particle swelling was observed using dynamic light scattering. With increasing pH, both the AA‐ and MAA‐based latexes showed significant increase in hydrodynamic diameter as a consequence of the dissociation state of carboxyl groups. However, only MAA‐based latexes exhibit very pronounced increase in viscosity and storage modulus, and were therefore characterized as gels. The effect of feeding strategies was found to be more pronounced with the MAA functionalized latexes. By employing mentioned three procedures, significant differences in the rheological behavior of the neutralized dispersions were detected. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42062.

Coalescing aids are organic solvents that are widely used to accommodate the film formation of waterborne coatings. The influence of the volatility, hydrophilicity, and amount of coalescing aids on the properties of waterborne dispersions and the dynamics of film formation was investigated. The results show that coalescing aids increased the viscosity through particle swelling and solvation, with the effect being stronger with more hydrophilic solvents. The results obtained with electrochemical impedance spectroscopy (EIS) and indentation tests show that hydrophilic coalescing aids were more efficient because of the partitioning on the particle interfaces but they could temporarily decrease the water resistance. The ease of coalescence was countered by solvent retention, which complicated the dynamics of film formation. EIS was used to optimize a real‐world coating formulation and identify the pitfalls arising from the complex dynamics of film formation. The best resistance to humidity was obtained with a combination of hydrophobic and hydrophilic coalescing aids. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45142.

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High solid (HS) alkyd resins with low amount of volatile organic compounds (VOC) were developed as the result of new VOC solvent directive that limit the amount of VOC in decorative paints. Due to specific chemical structure of HS alkyd resins and possible deterioration of some applicative properties the optimal combination of driers is an important subject of research. In our present work we studied the influence of Fe bispidon (Fe drier) and Co ethylhexanoate (Co drier) surface driers with Sr carboxylate (Sr drier) through drier on the film formation of HS alkyd coatings. The kinetics of autoxidation was analysed using FT-IR spectroscopy. Further, applicative properties like drying time and film hardness were examined. In the end, electrochemical impedance spectroscopy (EIS) was used to evaluate the quality of cured HS alkyd coating films after exposure in the humidity chamber. It was established that the addition of the Sr drier to surface driers accelerates the autoxidation process. As higher amounts of the Sr drier were added, final drying times were reduced and film hardness increased. The lowest diffusivity of ions through cured HS alkyd coating films was observed for Co/Sr and Fe/Sr drier combination at 1:1 concentration ratio.

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The film formation process in waterborne (WB) epoxy coatings is studied using electrochemical impedance spectroscopy (EIS) measurements and dynamic mechanical analysis (DMA). Ten epoxy coatings with different pigment volume concentration were prepared on standard steel substrates and carefully monitored over four weeks (30 days). It is shown that impedance spectroscopy can serve as a very sensitive tool for accurate experimental detection of the critical pigment volume concentration. We also show that the optimal film formation process and corrosion stability of coatings are greatly affected by the coating pigment volume concentration (PVC) value. As a whole, the study confirms that the optimization of coating protection ability needs to take into account both maximization of the barrier effect as well as maximization of the degree of epoxy-amino cross-linking.