Chemical and electrochemical grafting of polythiophene onto poly(vinyl chloride): synthesis,characterization, and materials properties

A facile strategy for chemical and electrochemical grafting of polythiophene onto poly(vinyl chloride) (PVC) is reported. For this purpose, a thiophene-functionalized PVC macromonomer (ThPVCM) was synthesized using a Kumada cross-coupling reaction. The synthesis of macromonomer was verified by means of Fourier transform infrared (FTIR) and ¹H nuclear magnetic resonance (NMR) spectroscopes. The graft copolymerization of thiophene monomers onto ThPVCM was initiated by oxidized thiophene groups coupled onto PVC backbone after addition of ferric chloride (FeCl₃) via oxidation polymerization method. Moreover, the electrochemical graft copolymerization of thiophene onto ThPVCM was performed via constant potential electrolysis in the acetonitrile (ACN)–tetraethylammonium tetrafluoroborate (TEAFB) solvent–electrolyte couple. The PVC-g-PTh obtained was characterized by means of FTIR spectroscopy and gel permeation chromatography (GPC), and its electroactivity behavior was verified under cyclic voltammetric conditions. Moreover, thermal behavior of the synthesized polymer was investigated by means of thermogravimetric analysis (TGA).     

Chemical and electrochemical grafting of polyaniline onto poly(vinyl chloride): synthesis,characterization, and materials properties

We have designed and developed a new strategy for the chemical and electrochemical graft copolymerization of aniline onto poly(vinyl chloride). For this purpose, first phenylamine groups were incorporated into poly(vinyl chloride) via a nucleophilic substitution reaction in the presence of a solvent composed of 4‐aminophenol, potassium carbonate, and dry N,N‐dimethylformamide at room temperature, in order to avoid cross‐linking. The macromonomer obtained was used in chemical and electrochemical oxidation copolymerization with aniline monomer to yield a poly(vinyl chloride)‐g‐polyaniline (PVC‐g‐PANI) graft copolymer. The chemical structures of samples as representatives were characterized by means of Fourier transform infrared and ¹H nuclear magnetic resonance spectroscopies. The electroactivity behaviors of the synthesized samples were verified under cyclic voltammetric conditions. The electrical conductivity and electroactivity measurements showed that the PVC‐g‐PANI graft copolymer has lower electrical conductivity as well as electroactivity than those of the pure PANI. However, the lower electrical conductivity and electroactivity levels in this material can be improved at the price of solubility and processability. Moreover, the thermal behavior and chemical composition of the synthesized graft copolymer were investigated. Copyright © 2016 John Wiley & Sons, Ltd.     

Erratum to: Chemical and electrochemical grafting of polythiophene onto poly(vinyl chloride): synthesis,characterization, and materials properties

Journal of Solid State Electrochemistry -     

Tragacanth gum‐based pH‐responsive magnetic hydrogels for “smart” chemo/hyperthermia therapy of solid tumors

The drug delivery performances of pH‐responsive magnetic hydrogels (MHs) composed of tragacanth gum (TG), poly(acrylic acid) (PAA), and Fe₃O₄ nanoparticles (NPs) were investigated in terms of physicochemical as well as biological features. The fabricated drug delivery systems (DDSs) were analyzed using Fourier transform infrared spectroscopy, X‐ray diffraction, vibrating sample magnetometer, scanning electron microscopy, and transmission electron microscopy. The synthesized MHs were loaded with doxorubicin hydrochloride (Dox) as a universal model anti‐cancer drug. The MHs showed excellent Dox loading and encapsulation efficiencies, mainly due to strong hydrogen bonding and electrostatic interaction between the drug and polymeric matrix, as well as porous micro‐structures of the fabricated MHs. The drug‐loaded MHs showed negligible drug release values in physiological condition. In contrast, in cancerous condition (pH 5.0), both MHs exhibited highest drug release values that qualified them as “smart” DDSs. The cytocompatibilities of the MHs as well as the cytotoxicity of the Dox‐loaded MHs were investigated against human epidermoid‐like carcinoma (Hela) cells through MTT assay. In addition, hyperthermia therapy induced by Fe₃O₄ NPs was applied to locally raise temperature inside the Hela cells at 45 ± 3°C to promote cell death. As a result, the Dox‐loaded MHs can be considered as potential DDSs for chemo/hyperthermia therapy of solid tumors.     

Synthesis and characterization of potential multifunctional methacrylate-based dental monomers

Research on Chemical Intermediates - We describe synthesis and characterization of a series of novel multifunctional methacrylate-based dental monomers. Triethanolamine was reacted with glycidyl...     

Polystyrene‐modified novolac epoxy resin/clay nanocomposite: Synthesis,and characterization

A polystyrene‐modified epoxidized novolac resin/montmorillonite nanocomposite was fabricated and characterized successfully. For this purpose, novolac resin (NR) was epoxidized through the reaction of phenolic hydroxyl group with epichlorohydrin in super basic medium to produce epoxidized novolac resin (ENR). Afterward, a polystyrene was synthesized by atom transfer radical polymerization (ATRP) technique, and then brominated at the benzylic positions using N‐bromosuccinimide (NBS). The brominated polystyrene (PSt‐Br) was reacted with ethanolamine in basic medium in order to afford an amine‐functionalized polystyrene (PSt‐NH₂). An organo‐modified montmorillonite (O‐MMT) was synthesized through the treatment of MMT with hexadecyl trimethyl ammonium chloride salt. Finally, ENR‐PSt/MMT nanocomposite was fabricated through curing a mixture of ENR (70 wt.%) and O‐MMT (5 wt.%) with PSt‐NH₂ (25 wt.%). Transition electron microscopy (TEM) and powder X‐ray diffraction (XRD) analysis revealed that the fabricated nanocomposite has an exfoliated structure. Thermal property studies using thermogravimetric analysis (TGA) showed that the curing of ENR by PSt‐NH₂, as well as incorporation of a small amount of MMT have synergistic effect on the thermal stability of the ENR resin.