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A new strategy for graft copolymerization of thiophene onto a polystyrene (PSt) backbone by a multi-step process is suggested and the effects of an organoclay on the final properties of the graft copolymer sample are described. For this purpose, first poly(styrene-co-4-chloromethyl styrene) [P(St-co-CMSt)] was synthesized via nitroxide-mediated polymerization. Afterwards, the chlorine groups of P(St-co-CMSt) were converted to thiophene groups using the Kumada cross-coupling reaction and thiophene-functionalized PSt multicenter macromonomer (ThPStM) was synthesized. The graft copolymerization of thiophene monomers onto PSt was initiated by oxidized thiophene groups in the PSt chains after addition of ferric chloride (FeCl 3 ), an oxidative catalyst for polythiophene synthesis, and FeCl 3 -doped polythiophene was chemically grafted onto PSt chains via oxidation polymerization. The graft copolymer obtained was characterized by 1 H NMR and Fourier transform infrared spectroscopy, and its electroactivity behavior was verified under cyclic voltammetric conditions. Finally, PSt-g-PTh/montmorillonite nanocomposite was prepared by a solution intercalation method. The level of dispersion of organoclay and the microstructure of the resulting nanocomposite were probed by means of XRD and transmission electron microscopy. It was found that the addition of only a small amount of organoclay (5 wt%) was enough to improve the thermal stabilities of the nanocomposite.

obtido foi caracterizado por espectroscopia no infravermelho por transformada de Fourier (FTIR), varredura diferencial de calorimetria (DSC) e análise termogravimétrica (TGA). Propriedades óticas do (PSt-co-PMSt)-g-PANI nos estados não-dopado e dopado foram obtidas usando espectroscopia no ultravioleta-visível (UV-Vis), e condutividade elétrica a temperatura ambiente foi medida usando amostras nas quais os materiais condutores foram ensanduichados entre dois eletrodos de Ni. Além disso, eletroatividade do terpolímero sintetizado foi verificada sob condições voltamétricas sobre a superfície do eletrodo de trabalho de carbono vítreo (GCE). A solubilidade do terpolímero (PSt-co-PMSt)-g-PANI foi examinada em solventes orgânicos comuns, tais como, tetrahidrofurano (THF), clorofórmio e xileno.This study aims to explore an effective route for the preparation of conductive N-substituted polyaniline (PANI) by the incorporation of brominated poly(styrene-co-p-methylstyrene) onto the emeraldine form of polyaniline. For this purpose, at first, poly(styrene-co-p-methylstyrene) was synthesized via nitroxide-mediated polymerization (NMP), and then, N-bromosuccinimide was used as brominating agent to obtain a copolymer with bromine. Thereafter, deprotonated polyaniline was reacted with brominated poly(styrene-co-p-methylstyrene) to prepare the poly(styrene-co-p-methylstyrene)-graft-polyaniline [(PSt-co-PMSt)-g-PANI] terpolymer through N-grafting reaction. The terpolymer was characterized by Fourier transform infrared (FTIR) spectroscopy, differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). Optical properties of (PSt-co-PMSt)-g-PANI in the undoped and doped states were obtained by ultraviolet-visible spectroscopy (UV-Vis), and electrical conductivity at room temperature was measured using samples in which the conductive materials was sandwiched between two Ni electrodes. Moreover, electroactivity of the synthesized terpolymer was verified under cyclic voltammetric conditions on the surface of the working glassy carbon electrode (GCE). The solubility of (PSt-co-PMSt)-g-PANI terpolymer was examined in common organic solvents, such as, tetrahydrofuran (THF), chloroform and xylene.

A new strategy for graft copolymerization of aniline onto polystyrene by a multi step process is suggested.

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A novel stimuli‐responsive magnetite nanohydrogel (MNHG), namely [poly(ethylene glycol)‐block‐poly(N‐isopropylacrylamide‐co‐maleic anhydride)2]‐graft‐poly(ethylene glycol)/Fe3O4 [PEG‐b‐(PNIPAAm‐co‐PMA)2]‐g‐PEG/Fe3O4, was successfully developed. For this purpose, NIPAAm and MA monomers were block copolymerized onto PEG‐based macroinitiator through atom transfer radical polymerization technique to produce PEG‐b‐(PNIPAAm‐co‐PMA)2. The synthesized Y‐shaped terpolymer was crosslinked through the esterification of maleic anhydride units using PEG chains to afford a hydrogel. Afterward, magnetite nanoparticles were incorporated into the synthesized hydrogel through the physical interactions. The chemical structures of all synthesized samples were characterized using Fourier transform infrared and proton nuclear magnetic resonance spectroscopies. Morphology, thermal stability, size, and magnetic properties of the synthesized MNHG were investigated. In addition, the doxorubicin hydrochloride loading and encapsulation efficiencies as well as stimuli‐responsive drug release ability of the synthesized MNHG were also evaluated. The drug‐loaded MNHG at physiological condition exhibited negligible drug release values. In contrast, at acidic (pH 5.3) condition and a little bit higher temperature (41 °C) the developed MNHG showed higher drug release values, which qualified it for cancer chemotherapy due to especial physiology of cancerous tissue in comparison with the surrounding normal tissue. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46657.

For the first time, synthesis and characterization of polystyrene-graft-polythiopheneviaa combination of atom transfer radical polymerization and Grignard reaction is reported.