Bulk homopolymerization and copolymerization of 1-hexene (H) with polar monomers including butyl acrylate (B) and methyl methacrylate (M) in the presence of 1,4-bis (2,6-diisopropylphenyl) acenaphthene diimine nickel (II) dibromide catalyst were investigated. Two cocatalysts, including diethyl aluminium chloride (DEAC) and ethyl aluminium sesqui chloride (EASC), were used to activate the catalyst at ambient temperature. In both the homopolymerization and copolymerization of 1-hexene with polar monomers, the catalyst activity resulted from EASC as cocatalyst was higher than that resulted from DEAC. 1 HNMR analysis was used in order to determine incorporation level of polar monomers and branching density of the synthesized polymers. A highest incorporation level of 13.3% mol was obtained using monomer

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Poly(methyl methacrylate), polystyrene, and poly(styrene‐co‐methyl methacrylate) cationically stabilized latexes with up to 25% solid content were prepared by surfactant‐free emulsion polymerization (SFEP) employing 1 mol % 2,2′‐azobis[2‐(2‐imidazolin‐2‐yl)propane]dihydrochloride (VA‐044) as an initiator and stabilizer (inisurf) with respect to monomer at 70 °C. The latexes had 200–500 nm z‐diameter and a very narrow size distribution (PDI < 0.05). The stabilizing amidinium moieties from VA‐044 were covalently bound to the particles. After drying in air, poly(styrene‐co‐methyl methacrylate), PS‐co‐PMMA latexes were easily redispersible in water simply by addition of water and a few minutes of gentle stirring. The redispersed latex particles had colloidal characteristics very similar to the original latex particles in terms of polydispersity, size, and zeta potential. In contrast, latexes prepared with a similar formulation but using a conventional cationic surfactant (CTAB) that was not covalently bound to the particles were not redispersible. This is the simplest method reported so far for the preparation of redispersible latexes that do not use high stabilizer concentrations. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 2376–2381

The present study deals with the synthesis and electrospining of a new terpolymer nanofiber in order to determine the amount of diazinon and chlorpyrifos in water and fruit juice samples. The synthesized terpolymer and the prepared nanofiber were characterized using 1H NMR spectroscopy, FTIR spectroscopy, scanning electron microscopy, and gel permeation chromatography. The performance of terpolymer nanofiber, prepared as a sorbent for micro solid phase extraction was investigated for the extraction of diazinon and chlorpyrifos from aquaeous media. Then, the target analytes were desorbed from the coating with an organic solvent and analyzed by gas chromatography with flame ionization detector. Extraction efficiencies were significant (>90%) under the optimum condition. The proposed method also demonstrated good linear dynamic ranges for diazinon and chlorpyrifos (3–250 and 5–200 µg/L), and low limit of detections (0.5 and 0.7 µg/L) respectively. Moreover, under optimum condition for extraction of diazinon and chlorpyrifos, square of correlation coefficients (R2) of 0.9978 and 0.9953 and relative standard deviations of 4.6 and 5.1% were achieved, respectively. The recoveries for diazinon and http://chlorpyrifos were in the range of 85–97%.