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The development of more sustainable materials from renewable resources has increasingly gained attention. In this work, commercial limonene oxide was used as a monomer to obtain polyesters with phthalic and maleic anhydrides. The ionic liquid 1-n-butyl-3-methylimidazolium heptachlorodiferrate (BMI·Fe2Cl7) was the catalyst for ring-opening polymerization. For both cyclic anhydrides, conversions around 80% were reached with a 1:100 catalyst:limonene oxide molar ratio. The resulting polymers presented a perfectly alternating structure, number-average molar mass over 1000 g mol−1, and pendant double-bonds that allow subsequent modification of their structures. Regarding their application, such as nanodevices for biological systems, poly(phthalic anhydride-co-limonene oxide) (PPALO) nanoparticles (NPs) were also produced and cross-linked with tetrathiol via thiol-ene reaction. The cross-linked PPALO-NPs with a number-weighted mean diameter of 56 nm, spherical morphology, and good colloidal stability were obtained. These NPs were tested for blood compatibility with human red blood (erythrocytes) cells and cell viability using mouse embryo fibroblast (NIH3T3) cell line, presenting potential for biomedical applications. [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 present work addresses the modeling and simulation of the addition of copolymerizations of styrene and methyl methacrylate in batch mode, and the formation of tailored vinyl acetate/acrylic acid copolymers is evaluated through stochastic optimization procedures based on the Monte Carlo method. A kinetic model of the free-radical reaction was proposed in order to predict the behavior of the reaction system taking into consideration the presence of the penultimate unit effect. The profiles of conversion and copolymer composition were also evaluated considering the effect of the medium viscosity (kinetic phenomena related to gel and glass effects) on the reaction performance. It was shown that the proposed model for chain-growth copolymerization is able to describe strong nonlinear behaviors such as autoacceleration of the polymerization and drift of copolymer composition. It was also shown that copolymers with homogeneous composition can be successfully synthesized through manipulation of the monomer feed flow rate based on a stochastic optimization procedure. [ABSTRACT FROM AUTHOR]

ABSTRACT Polymers based on renewable sources are promising materials, and can find many uses in coatings and adhesive applications. The goal of this work was to synthesize and characterize bio-based styrene/acrylated fatty acid methyl ester (AFAME) copolymer-poly(styrene- co-AFAME) prepared by miniemulsion polymerization. The main strategy adopted was to functionalize the bio-monomer with acrylic acid that was confirmed by 1H NMR and FTIR measurements, to allow its free-radical homo- or copolymerization with styrene. Poly(styrene- co-AFAME) with different AFAME content were obtained and their composition were evaluated by 1H NMR. Dynamic light scattering measurements throughout the reactions have indicated a very stable colloidal systems and average particles size ranges 100-150 nm. The structural and physical properties of poly(styrene- co-AFAME) were investigated by DTG-DTA, DSC which displayed a decreasing of glass transition temperature with increase of AFAME content. The results showed in this study have indicated that the poly(styrene- co-AFAME) can be used in several fields because their characteristics are totally distinct. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 1422-1432 [ABSTRACT FROM AUTHOR]

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 K&#945 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. [ABSTRACT FROM AUTHOR]

The present work addresses the synthesis and characterization of a new bio-nanocomposite based on acrylated fatty acids (AFA) derived from castor oil, ethyl acrylate and AFA surface modified γ-Fe 2 O 3 (γ-Fe 2 O 3 @AFA) magnetic nanoparticles (MNPs). It was shown that the in situ formed bio-nanocomposite containing around 2.0 wt.% of γ-Fe 2 O 3 MNPs with average particle size of ca. 9.0 nm, as determined by XRD and TEM measurements, displayed good magnetic response and superparamagnetic behavior. The magnetization measurements indicated that the incorporation of γ-Fe 2 O 3 @AFA MNPs into the poly(ethyl acrylate- co -AFA) matrix did not affect the magnetization saturation, remanence and coercivity of the MNPs, preserving the magnetic properties of the γ-Fe 2 O 3 precursor. Additionally, the use of AFA to chemically modify the surface of MNPs opens a new scenario on the chemical modification of MNPs with agents that undergo free-radical reactions, allowing for the proper dispersion of MNPs into the thermoplastic polymer matrices and minimizes the undesired leaching of the MNPs. [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]

Graphical abstract A biobased monomer acrylated ricinoleic acid was synthesized from castor oil and copolymerized with methyl methacrylate in miniemulsion forming polymeric nanoparticles. The addition of the biobased monomer led to a decrease in the glass transition temperature of the copolymer and to the formation of a small fraction of gel, resulting in materials with interesting properties for future applications. Highlights • A biobased monomer acrylated ricinoleic acid was synthesized from castor oil. • The biobased monomer was copolymerized with methyl methacrylate in miniemulsion forming polymeric nanoparticles. • Polymers with lower Tgs were obtained with the addition of the biobased monomer. • The copolymers exhibited interesting properties for future applications as adhesives. Abstract Vegetable oils-based polymers are promising materials with application in the industry of coatings and adhesives. Chemically-modified ricinoleic acid obtained from castor oil was used in this study to produce polymeric materials. The adopted strategy consisted in the epoxidation of the double bonds of ricinoleic acid, followed by the ring opening reaction in the presence of acrylic acid to form the acrylated ricinoleic acid (ARA). Free radical copolymerizations of ARA and methyl methacrylate (MMA) were carried out in miniemulsion, resulting in latexes stable over a long storage time. DLS measurements revealed the formation of submicron polymeric particles of different sizes strongly dependent on the fraction of the biobased monomer ARA, exhibiting diameters ranging from approximately 80 nm to 150 nm, as the ARA fraction was increased up to 80 wt%. It was possible to prepare polymers with broad ranges of mass-average molar masses in the range from 1137 kDa to 65 kDa and glass transition temperatures lying in the interval from approximately 124 °C–50 °C by varying the concentration of the comonomer ARA. Crosslinked copolymers were obtained by increasing the proportion of ARA. [ABSTRACT FROM AUTHOR]