Diazotization–azidation of amines in water by using crosslinked poly(4‐vinylpyridine)‐supported azide ion

The use of polymeric reagents simplifies routine azidation of diazonium salts, because it eliminates the traditional purification. An efficient, simple, and effective method for the preparation of aryl azides is described. The synthesis of aromatic azides from the corresponding amines is accomplished under mild conditions with sodium nitrite in the presence of p‐toluenesulfonic acid or concentrated H₂SO₄ at low temperature (0–5°C to room temperature). The obtained relatively stable diazonium salts, followed by treatment with a polymer‐supported azide ion in water at room temperature to produce the corresponding aryl azides. The spent polymeric reagents can be regenerated and reused for several times without losing their activity. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Solvent‐free diazotization–azidation of aryl amine using a polymer‐supported azide ion

Crosslinked poly (4‐vinylpyridine)‐supported azide ion was used as an effective azidating agent for deazodination of stable arenediazonium salts under solvent‐free conditions in high yields. The diazotization of aromatic amines was prepared by grinding the combination of an aromatic amine, sodium nitrite (NaNO₂), p‐toluene sulfonic acid (p‐TsOH), and 0.2 mL H₂O in a mortar. Grinding was continued for deazodination–azidation of the obtained relatively stable diazonium salts, with addition of crosslinked poly (4‐vinylpyridine) supported azide ion to obtain the corresponding aryl azides. The spent polymeric reagents can usually be removed and regenerated. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Synthesis and characterization of N‐methyl‐2‐nitrodiphenylamine‐4‐diazonium salt and its diazoresin

A new substituted diphenylamine diazonium salt, N‐methyl‐2‐nitrodiphenylamine‐4‐diazonium salt (MNDDS) and its diazoresin (MNDDS‐resin) were synthesized and their thermostability as well as photosensitivity were investigated. The results show that MNDDS and resin exhibit much higher thermostability than that of the parent compound, diphenylamine‐4‐diazonium salt (DDS) and resin (DDS resin) in solid state or in coating but the photosensitivities of them are confirmed to be in same level. The excellent thermostability of MNDDS and its diazoresin is very important because the storage life of a negative presensitized plate is mainly dependent on it. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 189–193, 1999     

Synthesis and characterization of N‐methyl‐2,6‐dinitrodiphenylamine‐4‐diazonium salt and its diazoresin

A new photosensitive agent, dinitro derivatives of diphenylamine diazonium salt (N‐methyl‐2,6‐dinitrodiphenylamine‐4‐diazonium salt, MDNDDS), and its diazoresin were synthesized. Their photoreactivities and thermostabilities were investigated. Our results revealed that MDNDDS and MDNDDS‐resin exhibited greatly improved thermostability both in solid state and in coating film comparing with the conventional unsubstituted and mononitro substituted diphenylamine diazonium salts (DDS and MNDDS, respectively) and their diazoresins. The photosensitivity of MDNDDS was found to be slightly lower than DDS but still comparable with MNDDS. As a result of its improved thermostability, both MDNDDS‐resin as a photosensitive agent and lithographic printing plate prepared by MDNDDS‐resin will have a long shelf‐life, which is very important to reduce waste and factory running‐cost. MDNDDS also has a maximum absorption wavelength (λ_max) at 425 nm, which means that an iodine gallium lamp (main emission wavelength λ_em = 420 nm), is better than conventional mercury lamp (λ_em = 360 nm), to be used as the irradiation source in the photoimaging process. Compared with the mercury lamp, iodine gallium lamp is cheaper and greener. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Trace metal ion retention properties of crosslinked poly(4‐vinylpyridine) and poly(acrylic acid)

The crosslinked resins poly(4‐vinylpiridine) (PVPy) and poly(acrylic acid) (PAA) were obtained by radical polymerization. PVPy shows monodentate ligands and PAA at basic pH is basically as acrylate anion, which can contain end‐carboxylates groups or form a bridge acting as mono‐ or bidentate ligands. The retention properties for trace metal ions from saline aqueous solutions and natural seawaters of these two resins were investigated by Batch equilibrium procedure. The metal ions studied were Cu(II), Pb(II), Cd(II), and Ni(II). The following effects were studied: pH, contact time, amount of the adsorbent, temperature, and salinity. The resin PVPy showed a high affinity for Cd(II) and PAA for Cu(II) and Cd(II). The metal ions were determined in the filtrate by atomic absorption spectrometry. By the treatment of the loaded resin with 4M HNO₃, it was possible to remove completely the Cu(II) ions. The retention properties of the resins were studied for trace metal ions present in the natural seawaters. Both resins showed a high affinity for Cd(II) when the natural seawater contained Cu(II) and Cd(II). © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2908–2916, 2004     

Convenient synthesis of sulfonamides from amines and p‐toluene sulfonyl chloride mediated by crosslinked poly(4‐vinylpyridine)

A general, mild, and convenient method has been developed for the synthesis of various N‐substituted and N, N‐disubstituted sulfonamides, as a class of sulfa drugs, from the corresponding amines and p‐toluene sulfonyl chloride in the presence of readily available crosslinked poly(4‐vinylpyridine) as a catalyst, base or polymeric substrates. The use of polymeric catalyst simplifies routine sulfonylation of amines because it eliminates the traditional purification. The polymer can be removed quantitatively and it can be regenerated and reused for several cycles without losing its activity. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Synthesis and swelling characteristics of poly(4‐vinylpyridine) gels crosslinked by irradiation

The effect of irradiation under vacuum on thermal properties and swelling behavior on poly(4‐vinylpyridine) (P4VP) was investigated. The gel percentage in the irradiated P4VP films was determined by Soxhlet extraction. UV spectroscopy was also used to determine sol percentage, which decreased as the radiation dose increased. The changes in thermal properties, such as glass‐transition temperature (T_g), were followed by differential scanning calorimetry before and after Soxhlet extraction. The gels prepared after irradiation were characterized with respect to their swelling properties and network structures. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 2609–2614, 2001     

Convenient synthesis of benzamides mediated by poly(4‐vinylpyridine)‐supported benzoyl chloride

The use of polymeric reagents simplifies the routine acylation of amines because it eliminates traditional purification. In this article, the use of readily available crosslinked poly(4‐vinylpyridine)‐supported benzoyl chloride as an acylating agent of amines in the presence of K₂CO₃ in n‐hexane is described. The product was readily obtained by the filtration and evaporation of the solvent. The spent polymeric reagent could be regenerated and reused. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Specific interactions in 4‐hydroxybenzoic acid/poly(2‐vinylpyridine)/poly(N‐vinyl‐2‐pyrrolidone) blends

The specific interactions in ternary 4‐hydroxybenzoic acid (HBA)/poly(2‐vinylpyridine) (P2VPy)/poly(N‐vinyl‐2‐pyrrolidone) (PVP) blends were studied by differential scanning calorimetry, Fourier transform infrared (FTIR) spectroscopy, and electron microscopy. FTIR study shows the existence of hydrogen‐bonding interactions between HBA and P2VPy as well as PVP. The addition of a sufficiently large amount of HBA produces a blend showing one glass‐transition temperature (T_g). Microscopic study shows a drastic reduction in domain size in single‐T_g blends. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 901–907, 2001     

Preparation of pH‐responsive crosslinked materials from natural rubber and poly(4‐vinylpyridine)

Stimuli‐responsive elastomers are smart materials for sensing applications. Natural rubber (NR) is a renewable elastomer with excellent elasticity and fatigue resistance. In this work, a straightforward method for the preparation of pH‐responsive crosslinked materials from NR and poly(4‐vinylpyridine) (P4VP) via free radical crosslinking reaction using benzoyl peroxide (BPO) as an initiator is described. The effects of P4VP and BPO concentrations, reaction time and reaction temperature on immobilization percentage were investigated. It was found that the immobilization percentage reached 90% when using a P4VP concentration of 150 phr and a BPO concentration of 10 phr for 24 h at 90 °C. The pH responsiveness of the crosslinked materials was studied via water swelling, water contact angle and dye release measurements. Unlike unmodified rubber, the P4VP‐crosslinked NR was found to be pH‐responsive in acidic solution. Indigo carmine adsorption studies showed the Langmuir isotherm suggesting monolayer coverage of dye on the rubber surface. The dye could also be released upon increasing the pH of solution above 4. Based on these results, the introduction of pH responsiveness to NR will lead to novel responsive rubber‐based materials that can be used in biomedical and sensing applications. © 2016 Society of Chemical Industry     

Selective retention properties to silver(I) and mercury(II) ions of poly(4‐vinylpyridine) methyl iodide studied by the liquid‐phase polymer‐based retention technique

The retention of various metal ions by water‐soluble poly(4‐vinylpyridine) methyl iodide in conjunction with ultrafiltration membrane was investigated. The method is based on the retention of inorganic ions by this polymer in a membrane filtration cell and subsequent separation of low‐molecular weight species from the polymer metal ion complex formed. It is shown that the polychelatogen can bind silver(I) and mercury(II) ions in aqueous solution at pH 1. At higher pH, the water‐soluble polymer can be applied to the separation and preconcentration of silver metal ions. Therefore, this polychelatogen is highly selective to Hg(II) at pH 1 with respect to metal ions such as Cd(II) and Zn(II). © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 2578–2582, 2001     

Synthesis of azo chromophores by using a polymer‐supported sodium nitrite

Polymer supported reagents especially anion exchange resins have been widely applied in organic synthesis. The recent developments in polymer‐supported reactions have led to the propagation of combinatorial chemistry as a method for the rapid and efficient preparation of novel functionalized molecules. An interesting and fast growing branch of this area is polymer‐supported reagents. In this study, diazonium salts are generated and are coupled with a coupling component by using a polymer supported nitrite and a polymeric acid. In this procedure, the azo chromophores are formed in a clean and efficient manner, the work‐up is easy and yields are high to excellent. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Preparation and catalytic application of poly 4‐vinylpyridine microspheres

Poly 4‐vinylpyridine (P4VP) microspheres between 170 and 728 nm were synthesized by Emulsifier‐Free Emulsion Polymerization. The monomer concentration, ionic strength, and initiator concentration affected the microsphere size and size distribution. The increasing monomer concentration led to the increase of microsphere size, whereas the size distribution of the resultant P4VP microspheres increased with the increasing ionic strength of the reaction systems. Mo(O₂)₂O·2DMF was successfully anchored onto the P4VP microspheres by ligand exchange, and the heterogeneous catalyst showed high‐catalytic activity for epoxidation of cis‐cyclooctene with environmentally friendly hydrogen peroxide. The size and morphology of the supported microspheres has important influence on the catalytic activity. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Blends containing amphiphilic polymers IV. Poly(N‐1‐alkyl itaconamic acids) with poly(2‐vinylpyridine) and poly(4‐vinylphenol)

The phase behavior of blends containing Poly(N‐1‐alkyl itaconamic acids) (PNAIA) with Poly(2‐vinylpyrindine) (P2VPy) and Poly(4‐vinylphenol) (P4VPh) were analyzed by Diferential Scanning Calorimetry (DSC) and Fourier Transform Infrared Spectroscopy (FTIR). Miscibility over the whole range of compositions is observed in both systems. All the blends show thermograms exhibiting distinct single glass transition temperatures (T_g), which are intermediate to those of the pure components. The Calorimetric Analysis using Gordon Taylor, Couchman, and Kwei treatments allows conclusion that interactions between the components is favorable to the miscibility. FTIR analysis of the blends suggests that the driving force for miscibility is hydrogen bonding formation. The variation of the absorptions of the carbonyl groups of PNAIA and the hydroxyl groups of P4VPh allows one to attribute the miscibility to weak acid base like interactions. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 1245–1250, 2002; DOI 10.1002/app.10453     

Highly efficient interpenetrating polymerization of styrene and 4‐vinylpyridine with poly(ethylene terephthalate) using benzoyl peroxide

A polymerization method for the preparation of an interpenetrating network polymer with poly(ethylene terephthalate) is reported. Two types of monomer, styrene and 4‐vinylpyridine, were chosen as hydrophobic and hydrophilic representatives, respectively, in order to show the versatility of this polymerization method. The polymer‐immobilized poly(ethylene terephthalate) samples were characterized using Fourier transform infrared spectroscopy, scanning electron microscopy and X‐ray photoelectron spectroscopy. The immobilization efficiency of styrene as a function of reaction temperature, monomer‐to‐initiator molar ratio, reaction time, addition of solvent, surface hydrophilicity and immersion in initiator was studied. The maximum immobilization percentage of styrene reaches 111%. The immobilization efficiency is proportional to polymer molecular weight and sample thickness. Based on these results, this strategy is shown to be an efficient, versatile method for preparing interpenetrating network polymers and can be used as a means to modify the structures and properties of polymeric substrates. © 2013 Society of Chemical Industry     

Conducting properties of iodine‐doped low‐density polyethylene–poly(4‐vinylpyridine) blends

The conductivities of blends of low‐density polyethylene and poly(4‐vinyl pyridine) (P4VP) were studied. The blends were synthesized by in situ sorption and thermal polymerization of 4‐vinylpyridine in low‐density polyethylene. They showed, after iodine doping, conductivities of 1.7 to 5.0 × 10^?7 S cm^?1 at 298 K, depending on the P4VP mass increment into the matrix. Their conductivities were one order of magnitude higher for measurements at 338 K. The optimum ratio of iodine to pyridine (n) which gave the highest conductivity was 0.21. The thermal stability of doped blends was acceptable for their uses as electrochemical devices. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 939–944, 2003     

Synthesis mechanisms of poly[styrene‐co‐(acrylic acid)]‐supported TiCl4 catalysts modified by magnesium compounds

Soluble poly[styrene‐co‐(acrylic acid)] (PSA) modified by magnesium compounds was used to support TiCl₄. For ethylene polymerization, four catalysts were synthesized, namely PSA/TiCl₄, PSA/MgCl₂/TiCl₄, PSA/(n‐Bu)MgCl/TiCl₄, and PSA/(n‐Bu)₂Mg/TiCl₄. The catalysts were characterized by a set of complementary techniques including X‐ray photoelectron spectroscopy, Fourier‐transform infrared spectroscopy, X‐ray diffraction, thermogravimetric analysis, scanning electron microscopy, and element analysis. Synthesis mechanisms of polymer‐supported TiCl₄ catalysts were proposed according to their chemical environments and physical structures. The binding energy of Ti 2p in PSA/TiCl₄ was extremely low as TiCl₄ attracted excessive electrons from ? COOH groups. Furthermore, the chain structure of PSA was destroyed because of intensive reactions taking place in PSA/TiCl₄. With addition of (n‐Bu)MgCl or (n‐Bu)₂Mg, ? COOH became ? COOMg‐ which then reacted with TiCl₄ in synthesis of PSA/(n‐Bu)MgCl/TiCl₄ and PSA/(n‐Bu)₂Mg/TiCl₄. Although MgCl₂ coordinated with ? COOH first, TiCl₄ would substitute MgCl₂ to coordinate with ? COOH in PSA/MgCl₂/TiCl₄. Due to the different synthesis mechanisms, the four polymer‐supported catalysts correspondingly showed various particle morphologies. Furthermore, the polymer‐supported catalyst activity was enhanced by magnesium compounds in the following order: MgCl₂ > (n‐Bu)MgCl > (n‐Bu)₂Mg > no modifier. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Synthesis of poly(styrene‐co‐4‐vinylpyridine) microspheres via dispersion polymerization: Effect of the concentration of 4‐vinylpyridine

Amphiphilic copolymer microspheres of poly(styrene‐co‐4‐vinylpyridine) were prepared by dispersion polymerization in an alcohol/water medium. The synthesis of poly(styrene‐co‐4‐vinylpyridine) microparticles was successfully carried out, and the latexes had a spherical morphology with good monodispersity. The degree of conversion in the early stage of polymerization decreased with increasing 4‐vinylpyridine (4VP) monomer content, but the final conversions were similar (>95%). The copolymerization rate decreased with increasing 4VP content, and a broad particle size distribution was observed with 20 wt % 4VP because of the prolonged nucleation time. With the 4VP concentration increasing, the molecular weight of the copolymer microspheres decreased, and the glass‐transition temperature of the copolymers increased; this indicated that all the copolymers were random and homogeneous. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Polymer electrolyte membranes composed of an electrospun poly(vinylidene fluoride) fibrous mat in a poly(4‐vinylpyridine) matrix

Newly proposed polymer electrolyte membranes (PEMs) composed of an electrospun poly(vinylidene fluoride) (PVDF) fibrous mat embedded in a poly(4‐vinylpyridine) (P4VP) matrix were successfully fabricated in order to improve the mechanical and dimensional stabilities and ionic conductivity of membranes in lithium rechargeable batteries. Fourier transform infrared spectroscopic analysis showed that as a result of the use of a high voltage during electrospinning the crystalline structure of PVDF changed partially from α‐phase to β‐phase. Energy‐dispersive X‐ray spectroscopy confirmed the existence of crosslinked P4VP in the PVDF fibrous mat. The electrolyte uptakes of PVDF and PVDF/P4VP composite mats were higher than that of PVDF cast film. The tensile properties of PVDF/P4VP composite mat were considerably improved compared to those of the pristine PVDF fibrous mat under both dry and wet (soaked with electrolyte) conditions. In addition, the mechanical and dimensional stabilities of the PVDF/P4VP composite PEM were further enhanced due to crosslinking between the P4VP chains. Furthermore, the PVDF/P4VP composite PEM exhibited an ionic conductivity that was an order of magnitude higher than that of traditional PVDF film. © 2012 Society of Chemical Industry     

The phase behavior and thermal stability of blends of poly(styrene‐co‐methacrylic acid)/poly(styrene‐co‐ 4‐vinylpyridine)

The hydrogen bonding and miscibility behaviors of poly(styrene‐co‐methacrylic acid) (PSMA20) containing 20% of methacrylic acid with copolymers of poly(styrene‐co‐4‐vinylpyridine) (PS4VP) containing 5, 15, 30, 40, and 50%, respectively, of 4‐vinylpyridine were investigated by differential scanning calorimetry, thermogravimetric analysis (TGA), and Fourier transform infrared spectroscopy (FTIR). It was shown that all the blends have a single glass transition over the entire composition range. The obtained T_gs of PSMA20/PS4VP blends containing an excess amount of PS4VP, above 15% of 4VP in the copolymer, were found to be significantly higher than those observed for each individual component of the mixture, indicating that these blends are able to form interpolymer complexes. The FTIR study reveals presence of intermolecular hydrogen‐bonding interaction between vinylpyridine nitrogen atom and the hydroxyl of MMA group and intensifies when the amount of 4VP is increased in PS4VP copolymers. A new band characterizing these interactions at 1724 cm⁻¹ was observed. In addition, the quantitative FTIR study carried out for PSMA20/PS4VP blends was also performed for the methacrylic acid and 4‐vinylpyridine functional groups. The TGA study confirmed that the thermal stability of these blends was clearly improved. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011