In this work, the emulsion copolymerization of styrene and acrylated methyl oleate (AMO), a monomer derived from oleic acid (OA), has been evaluated. Reactions exhibiting high monomers conversions were successfully performed, leading to the formation of very stable polymer lattices, whose average particle size is kept unchanged for relatively high storage times. The average molar masses determined by gel permeation chromatography showed to be very dependent on the amount of AMO in the reaction medium, presenting experimental values within the range from 280 000 to 39 000 g mol À1 with molar mass dispersity ranging from 4 to 2 when the AMO fraction in the reaction medium was increased to 40 wt%. The nucleation rate was affected by AMO in such way that an increase in AMO concentration must be accompanied by an increase in initiator concentration, which leads to the reduction of the average molar masses of the copolymer. The thermal analyses of the polymer materials showed that the glass transition temperature decreased with increasing amount of AMO in the copolymer chains.Practical applications: The use of vegetable oils and their derivatives as precursor monomers in polymerization reactions has increased each day due to their renewable origin. Among them, OA deserves special attention due to the high availability and ease of chemical modification, mainly when the double bounds are considered. Results showed that AMO could be incorporated at high ratios in emulsion polymerization reducing the glass transition temperatures of the copolymer. The polymer lattices also showed good storage stability.

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In this study, we synthesized a new class of copolymeric lattices based on vinyl pivalate (VPi) and modified oleic acid (OA) through a batch emulsion polymerization process. The effects of the chemically modified OA [methacrylated methyl oleate (MAMO)] on the thermal stability, glass‐transition temperature (Tg), average molar masses [mass‐average molar mass (Mw) and number‐average molar mass (Mn)], and molar mass dispersity (Ð) of the copolymers were evaluated. The experimental results indicate that via the introduction of MAMO into the polymer chains resulted in significant reductions in Tg, Mw, Mn, and Ð; this demonstrated a decrease of Tg at approximately 40 °C when the MAMO molar fraction equaled 9% compared to the value observed for the pure poly(vinyl pivalate) (PVPi), which was equal to 80.5 °C. MAMO incorporation led to a significant decrease in the Mw value observed in the interval, with a differential from approximately 1.6 × 103 to 289.6 kg/mol, and Ð values between 2.17 to 1.55, which was when the MAMO molar fraction present in the VPi‐containing copolymers varied from zero (pure PVPi) to approximately 9 mol %. We also observed that the thermal stability of the copolymers decreased slightly when the MAMO concentration increased in the reaction medium. Despite this minor drawback, polymer lattices with a high colloidal stability were formed at a high rate of polymerization, and the elevated conversion was within the interval 90–100%. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 44129.

In this study, chia air-dry alkyd resins were synthesized from chia oil, glycerol, and phthalic anhydride in a two-step alcoholysis−polycondensation reaction. Various resins were synthesized consisting of varying oil lengths of 30, 45, 48, and 55%. The presence of functional groups of the chia alkyds was confirmed qualitatively by Fourier transform infrared (FTIR) spectroscopy and quantitatively by 1 H nuclear magnetic resonance (NMR) and 13 C NMR. Besides, a series of experiments were conducted to evaluate the effect of the process parameters on the alkyd resin synthesis, such as temperature, catalyst type, and concentration. The catalysts played a fundamental role in the formation of monoglycerides, reducing the alcoholysis completion time by more than half the time observed for reactions without catalysts from 185 to 90 min approximately, along with a satisfactory reaction temperature of 220 °C to avoid catalyst degradation and undesirable effects on oil quality. The characterization indicated esterification, the presence of unsaturated bonds on fatty acid chains, and aromatic structures. Furthermore, a viscosity test was performed on each of the alkyds, as the viscosity dictates the film formation and surface characteristics. Gel permeation chromatography indicated that the resins were of low molecular weight and increased viscosity. The results indicated that differences in oil and phthalic anhydride concentrations in the formulations affected the polymer properties, such as viscosity, number-average molecular weight (M n ), and weight-average molecular weight (M w ) of the resin. The chia alkyd resin of 30% oil composition expressed a M w of 6724 g•mol −1 and a viscosity of 33 833 cP, and the resin of 55% oil composition expressed a M w of 1294 g•mol −1 and a viscosity of 936 cP. Polycondensation reactions carried out at 220 °C provided balanced benefits of reaction time without risking catalysts or oil degradation. This study indicated that chia oil alkyd resins are suitable for surface coating binders and potentially a more effective substitute for linseed oil in the air-dry alkyd resins market.

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.

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This work focuses on the synthesis of a new class of copolymer materials consisting of traditional vinyl monomers (essentially, vinyl acetate, ethyl acrylate, and methyl methacrylate) and copper (II) methacrylate (Cu(II)MA) intended to be used as surface modification agents in electrochemical quantifications of organic and inorganic analytes. Voltammetry assays showed that when deposited on glassy‐carbon electrode (GCE), Cu(II)MA‐based copolymers are very promising materials to be applied in electrochemical determinations, exhibiting high analytical signal in the oxidation and reduction peaks during quantification of potassium hexacyanoferrate (III) in comparison to a bare GCE, contributing to increase the effective electrode area. When employed for the determination of ascorbic acid, PVAcCu(II)MA/GCE exhibited performance similar to that of the bare GCE. Polymers characterizations showed that glass transition temperature of the Cu(II)MA‐based materials increased in approximately 10–20°C, as consequence of the copper present in molecular structure of the copolymer chains (bidentate bridging coordination mode). Energy‐dispersive X‐ray spectroscopy measurements of Cu(II)MA monomer and Cu(II)MA‐based copolymers showed strong characteristic peaks Kα and Kβ at 8.04 and 8.90 keV, respectively, with an average amount of copper of 99%. The performance of the Cu(II)MA‐based copolymers modified electrodes is strongly dependent on the amount of copper into the copolymer chains and consequently on the monomers conversion. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43202.