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In this paper, copolymerization of methyl methacrylate (MMA) with n-butyl acrylate (BA) in a bubble column reactor using benzoyl peroxide as free radical initiator, at a temperature over 85 °C, is presented. This mode of copolymerization keeps an inert atmosphere throughout the entire reaction and contributes to proper mixing of the monomers. Higher pressure of the bubbling ensures the faster contact of the species, and a higher conversion was obtained in a shorter reaction time. The conversion of monomer at 124 Pa after 210 min is total, which is particularly noteworthy due to the absence of residual monomer that represents hazardous compounds, with negative impact upon employees and end-user safety. Higher conversions are obtained at 96 °C, 124 Pa nitrogen bubble pressure, 60/40% moles monomer ratio BA/MMA and 2% POB. The molar mass Mw, Mn and PDI decrease with the increase in temperature quite linearly. In the absence of nitrogen bubbling, the copolymer composition is approximately the same as in the feeding mixture. The corrosion protection efficiency of steel painted with these acrylic coatings was carried out by means of OCP and potentiodynamic polarization testing and electrochemical impedance spectroscopy (EIS).

We study the interaction of six systematically varied tetraphosphonate molecules with carbon steel surfaces by XPS at pH 3. All tetraphosphonates [EDTMP (C2), TDTMP (C4), HDTMP (C6), ODTMP (C8) and DDTMP (C12)] belong to the aminomethylene-phosphonate family, and they possess systematically elongated backbone (from two to twelve methylene groups separating the N atoms). XPS studies were performed on powdered samples and also on immersed carbon steel specimens in aqueous solutions. The XPS results also suggest that the tetraphosphonic acid molecules become significantly deprotonated upon interaction with the carbon steel surface and that the surface interaction of the tetraphosphonic acid family leads to additive adsorption on the steel surface via the phosphonate groups. The mode of corrosion inhibition was studied by potentiodynamic polarization and electrochemical impedance spectroscopy. The changes observed in the impedance parameters, like charge transfer resistance (Rct) and constant phase element (CPE) confirm the strong adsorption on the metal surface. The nature of the protective layer formed on the carbon steel surface was examined by Attenuated Total Reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy and optical microscopy.

The interactions of six homologous diphosphonate additives, methylamine-N,N-bis(methylenephosphonate) (MBMP, C1-D), ethylamine-N,N-bis(methylenephosphonate) (EBMP, C2-D), butylamine-N,N-bis(methylenephosphonate) (BBMP, C4-D), hexylamine-N,N-bis(methylenephosphonate) (HBMP, C6-D), octylamine-N,N-bis(methylenephosphonate) (OBMP, C8-D), dodecylamine-N,N-bis(methylenephosphonate) (DBMP, C12-D), with carbon steel surfaces are studied by XPS at pH = 3.0. Structurally, all additives possess two methylenephosphonate moieties connected to a single N atom. The third substituent on N is a non-polar, variable-length alkyl chain, –(CH2)xCH3, where x = 0 (C1-D), 1 (C2-D), 3 (C4-D), 5 (C6-D), 7 (C8-D), and 11 (C12-D). XPS studies (on pristine solid diphosphonate samples and also on carbon steel specimens, immersed in aqueous solutions), indicate significant deprotonation of the diphosphonic acid molecules upon interaction with the metallic surface. They also prove that this surface interaction results in adsorption on the surface via the deprotonated phosphonic acid moieties. The adsorption of inhibitors on the metal surface was investigated by potentiodynamic polarization and electrochemical impedance spectroscopy. The changes detected in the charge transfer resistance (Rct) and constant phase element (CPE) independently confirm inhibitor adsorption on metal surface. Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR) spectroscopy and Scanning Electron Microscopy was used to investigate the nature of deposited film. Small alkyl chain diphosphonates (C1-D, C2-D and C4-D) exhibited lower corrosion resistance due to the thin, porous and/or incomplete layer formed on carbon steel surface. Longer alkyl chain molecules (C6-D, C8-D and C12-D) were found to adsorb more efficiently and form a more organized and thicker layer. The best results were obtained in the case of C8-D (lower corrosion current, higher Rct and surface coverage). In the presence of C8-D the corrosion rate was reduced by a factor of 6.

The inhibition effect of N,N&prime, phosphonomethylglycine (PMG) and vinyl phosphonic acid (VPA) on the 3% NaCl acidic solution corrosion of carbon steel iron was studied at different immersion times by potentiodynamic polarization, electrochemical impedance spectroscopy, attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy, and computational methods. It is found from the polarization studies that PMG and VPA behave as mixed-type inhibitors in NaCl. Values of charge transfer resistance (Rct) and double layer capacitance (Cdl) in the absence and presence of inhibitors are determined. The PMG and VPA inhibitors were capable of inhibiting the corrosion process up to &asymp, 91% and &asymp, 85%, respectively. In the presence of PMG, the synergic effect of chlorine ions was observed. Density functional theory (DFT) was engaged to establish the adsorption site of PMG, VPA, and their deprotonated states. For studied compounds, the resulted values of ELUMO, EHOMO, energy gap (∆E), dipole moment (&mu, ), electronic hardness (&eta, ), global softness (&sigma, ), electrophilic index (&omega, ), and the electronic potential map are in concordance with the experimental data results regarding their corrosion inhibition behavior and adsorption on the metal surface.

Metalloporphyrins are highly recognized for their capacity to act as sensitive substances used in formulation of optical, fluorescent, and electrochemical sensors. A novel compound, namely Pt(II)-5,10,15,20-tetra-(4-allyloxy-phenyl) porphyrin, was synthesized by metalation with PtCl2(PhCN)2 of the corresponding porphyrin base and was fully characterized by UV-vis, fluorimetry, FT-IR, 1H-NMR, and 13C-NMR methods. The fluorescence response of this Pt-porphyrin in the presence of different concentrations of hydrogen peroxide was investigated. Besides, modified glassy carbon electrodes with this Pt-porphyrin (Pt-Porf-GCE) were realized and several electrochemical characterizations were comparatively performed with bare glassy carbon electrodes (GCE), in the absence or presence of hydrogen peroxide. The Pt-porphyrin demonstrated to be a successful sensitive material for the detection of hydrogen peroxide both by fluorimetric method in a concentration range relevant for biological samples (1.05&ndash, 3.9 &times, 10&minus, 7 M) and by electrochemical method, in a larger concentration range from 1 &times, 6 M to 5 &times, 5 M. Based on different methods, this Pt-porphyrin can cover detection in diverse fields, from medical tests to food and agricultural monitoring, proving high accuracy (correlation coefficients over 99%) in both fluorimetric and electrochemical measurements.

The chlorometylated styrene–divinylbenzene copolymer with different percent of divinylbenzene (code: S-6.7 DVB, S-12DVB, and S-15DVB) was functionalized with 3-hydroxybenzaldehyde for obtaining intermediated polymers. The aminotrimethoxysilanphosphonate groups were grafted by one-pot reactions in tetrahydrofuran using three components: polymers grafted with aldehyde groups (code: CHO-6.7, CHO-12, and CHO-15), 3-aminopropyltrimethoxysilane, diethylphosphite. The aminotrimethoxysilanphosphonate groups functionalized onto styrene-(6.7, 12, and 15%) divinylbenzene copolymer (code: PAF-6.7, PAF-12, and PAF-15) and evolution of the reaction were evidenced by FT-IR spectroscopy and porous structure by N2 adsorption-desorption, SEM microscopy. The thermal behavior of aldehydes and materials: PAF-6.7, PAF-12, and PAF-15 are different than initial polymer supports.

Herein, we report the synthesis, structural characterization and corrosion assay of a metal phosphonate – Mg(GLY)(H2O)2 obtained from a tridentate ligand N,N-bis-phosphonomethylglycine (GLY) and a magnesium salt (MgSO4·7H2O). The phosphonate was obtained by hydrothermal method at 80°C and also under ultrasounds conditions at 60°C. The FTIR, X-ray powder diffraction, elemental analysis and thermogravimetric analysis were performed in order to fully characterize the synthesized compounds and polarization experiments (CP) and electrochemical spectroscopy (EIS) to investigate the corrosion inhibition properties. The FTIR confirm the formation of magnesium phosphonate, and the X-ray diffraction showed the formation of a semi-crystalline compound. The elemental analysis confirmed the number of water molecules per formula unit of Mg(HO3PCH2)2N(H)CH2COO·2H2O. The presence of nitrogen atom and phosphonate groups in the metal phosphonate structure anticipated that the presence of the small quantity of Mg(GLY)(H2O)2 in saline solution will provide a positive effect on iron surface and act as a corrosion inhibitor. From the CP curves recorded in an aerated nitric saline solution, corrosion parameters (corrosion potential –Ecorr, corrosion density current – Jcorr, polarization resistance – Rp and corrosion rate – Rcorr) were extracted from Tafel plots. The decrease in Jcorr is associated with a shift in Ecorr to more negative values. These results suggest that metal phosphonate behaves as a mixed-type inhibitor, by reducing both the cathodic and anodic reactions. The optimum inhibitor concentration determined was 2 mM. At this concentration the corrosion rate decreases by 23% fold comparatively with iron in nitric acid solution without metal phosphonate. The EIS data in agreement with the polarization measurement resulted from polarization data.

Organophosphorus chemistry was developed in the last decade by promoting the synthesis reactions using ionic liquids either as solvent or catalyst. Ionic liquids (ILs), the so-called “green solvents”, have gained interest in the synthesis of organophosphorus compounds as alternatives to flammable and toxic organic solvents and catalysts. ILs have beneficial properties because they provide high solubility for many organic and inorganic compounds or metal complexes, have no vapor pressure, and are reusable. Also, in some cases, they can enhance the reactivity of chemical reagents. In this review, we aimed at showing the synthesis of different organophosphorus compounds under green and mild conditions using ILs as reaction media or catalysts, according to a trend developed in the last years. A novel trend is to perform these syntheses under microwave irradiation conditions together with ILs as solvents and catalysts.

The functionalization of S–1% DVB copolymer was carried out with aminophosphonate groups, and then the samples were covered with silica to obtain hybrid materials. The obtained hybrid materials were used as supports for impregnation of transition metal ions [Cu(II) and Mn(II)], and they were subsequently used as catalysts in oxidation reactions. The supports and catalysts were characterized by FTIR and UV–Vis spectroscopy, thermal analysis, SEM, and TEM electron microscopy. The results of FTIR spectroscopy indicated the formation of a hybrid of silica and an aminophosphonate polymer by the sol–gel route. The UV–Vis spectra showed a strong interaction of Cu(II) and a weak interaction of Mn(II) with aminophosphonate groups of the supports. The catalytic tests confirm different interactions between the metal cations and obtained supports. The formation of the immobilized Cu(II) complexes shows the possibility of using these materials selectively in oxidation of various organic compounds (anisole, cyclohexene, toluene, styrene, phenol). The purpose of this article is to develop some new poly(aminophosphonates)/silica hybrid materials immobilized with transition metal such as Cu(II) and Mn(II) ions for future use in the oxidation process.

The demand for corrosion inhibitors with low toxicity has increased in the last years in a wide range of sectors. Our study presents the synthesis, X-ray structure, thermal and kinetic investigation of ethylethanolammonium 4-nitrobenzoate (EEA4NB) as corrosion inhibitor for iron in 3% NaCl solution. Proton transfer and hydrogen bonding in the organic salt were elucidated and confirmed by infrared spectroscopy and single-crystal X-ray diffraction. Simultaneous TGA–DTA and heat flow analysis were used to study the thermal and kinetic behavior of EEA4NB. The results provided useful information about thermal stability and thermal decomposition. The non-isothermal kinetic parameters were estimated by using three different kinetic methods. Electrochemical corrosion measurements show corrosion inhibitor efficiency of EEA4NB for iron in 3% NaCl solution higher than 92% and a decrease of corrosion current and corrosion rate as a result of adsorption of EEA4NB molecules at the metal/solution interface.

In this paper, we present the synthesis of tris(4-hydroxybutyl acrylate) phosphate using 1-methylimidazole as acid scavenger for hydrochloric acid by-product, when an ionic liquid is formed. The synthesis was performed in the absence of any organic solvent. The yield is 83% for ester. The phosphate was characterized by 1H–31P NMR and FTIR. The obtained phosphate is appropriate monomer for UV curing in the presence of photoinitiator. The obtained polymer was characterized by thermal analysis and LOI. The results showed good thermal stability and flame retardancy of UV-cured polymer.

This paper is designated to the development of flame retardant solid polymer electrolytes based on phosphorus containing polymers. The new green technique synthesis, respectively polycondensation under microwave irradiation of hexylphosphonic dichloride (HPD) with 4,4′-(1,3-phenylenediisopropylidene) bisphenol (bisphenol M) was described. 86% yield and 0.95 dl g −1 inherent viscosity were obtained. The polyphosphonate was characterized by FT-IR, 1 H and 31 P NMR spectroscopy, gel permeation chromatography, and thermal analysis. The polymer presents thermal stability, begins to lose weight above 280 °C. The influence of the reaction temperature and reaction time on yield and inherent viscosity for MW polycondensation was studied and the results were compared with the results of polycondensation reaction under conventional heating in similar conditions. Best results were obtained under microwave irradiation. Solid polymer electrolytes were obtained from the polyphosphonate complexed with different lithium salts using casting technique and the electrochemical properties were determined. The low activation energy of conduction determined for solid polymer electrolyte membrane with bis(oxalato)borate anions overcomes the activation energy request for relaxation process and this membrane presents the best conductivity. Also, the flammability of polyphosphonate and membranes was investigated by measuring limiting oxygen index values.

Vinylphosphonic acid is homopolymerized with dimethylvinylphosphonate by radical polymerization using using UV light and photoinitiator Darocur 4265 (3 wt%). The molar ratio between vinylphosphonic acid and dimethylvinylphosphonate is varied between 1:1 and 4:1, respectively. The obtained homopolymer of vinylphosphonic acid and copolymers are characterized by Fourier transform infrared spectroscopy (FTIR), thermal analysis and size exclusion chromatography - multi angle laser light scattering. The polymerization by UV light is efficient and an average molar mass of 34,200 g/mol is obtained for poly(vinylphosphonic acid) and in the range from 12,700 to 19,120 g/mol for copolymers, which also have a good thermal stability until 320 °C. The polymers structure allows the formation of random coil conformation. The copolymers are tested as inhibitors against corrosion of iron in NaCl aqueous solution, and, as a result, it was shown that these copolymers exhibit promising anticorrosion properties.

One well-known method for hybrids synthesis with incorporated organic dyes is sol-gel method, which is based on the concept of molecular manipulation to design ceramics, glasses, and composites. The low-temperature process allows for the incorporation of guest organic molecules within the inorganic matrix, as well as for the synthesis of hybrid networks in which the organic and inorganic phases are interpenetrating. The aim of the work presented in this paper was the preparation of the gels with three different dyes, at different molar ratios by using the hydrolytic sol-gel process. The interaction of the dye and the oxide was examined by UV-vis spectroscopy and FT-IR. The thermal stability of the hybrid organic-inorganic xerogel formed here was studied by thermal analysis. The micrographs obtained by scanning electron microscopy (SEM) revealed the high density of the films. Such characteristics indicate the possible application of these films in solar cells.

Bromide ions are present in many environments, such as sedative drugs, methyl-bromide-treated vegetables and seawater. Excess bromide in humans interferes with iodide metabolism and is considered toxic. The need for fast and inexpensive methods for bromide detection is of interest. Spectrophotometric detection methods provide accurate and sensitive results. The well-known ability of metalloporphyrins to bind anionic ligands to the central metal ion has been exploited. The changes in the optical properties of Pt(II) 5,10,15,20-tetra(4-methoxy-phenyl)-porphyrin (PtTMeOPP) under the influence of bromide ions allowed us to achieve a fast, simple and reliable UV-vis spectrophotometric method of detection with a detection limit of 2.5 &times, 10&minus, 8 M and a good confidence coefficient: 99.05%. The potential interfering ions, such as Cl&minus, I&minus, NO2&minus, NO3&minus, SCN&minus, SO32&minus, SO42&minus, and PO43&minus, of 100-fold higher and Cl&minus, and R-S&minus, of 1000-fold higher concentrations in the mixture as compared to the determined concentration of bromide ions (c = 10&minus, 5 M), were tested and did not influence the results. The behavior of the sensitive porphyrin in various pH media was investigated in order to determine their influence upon the bromide detection capacity.

Polyphosphoesters are environmentally friendly and multifunctional materials. They were noted for their special properties, i.e. fire resistance, plasticity, lubricity, high physical-mechanical performance, thermal stability, and as degradable biopolymers which properties can be modified specifically to desired application in medicine, biology and agriculture. They have a wide range of application as: flame retardants, scaffolds for tissue engineering, gene carriers, drug delivery, carriers for the sustained release of nerve growth factor, pH/thermoresponsive materials, or as solid polymer electrolytes. In this paper we present our researches concerning the synthesis and application of polyphosphates, and polyphosphonates using different modern methods. Different approaches were used. These polyphosphoesters were used as solid polymer electrolytes for lithium polymer batteries by complexation of polyphosphoesters obtained from different phospho(n)ric dichlorides and aliphatic or aromatic diols with lithium salts. These polymers present two important features: they have good conductivity, around 10−6 S/cm, and are fire proof.

Phosphonate metal organic frameworks synthesized starting from a 1:1 ratio of corresponding nitrate and vinylphosphonic acid (VP) in hydrothermal conditions were analyzed by FTIR, X-Ray powder diffraction, elemental analysis and thermogravimetric analysis. The ability Co and Zn vinylphosphonate molecules to anchor on the surface of the iron were investigated. Their binding stability on iron surface in acid saline solution was tested by electrochemical methods (polarization curve- CP and electrochemical impedance spectroscopy -EIS) and ATR-FT-IR. A 2 mM concentration of CoVP allows the formation of a protective layer on the iron surface which provides 96.8% inhibitory efficiency (IE), close to that provided by the corresponding phosphonic acid VP. The low corrosion rate in the presence of CoVP as compared to ZnVP may be due to the lower hydrolytic stability of CoVP. Following the hydrolysis reaction, the phosphonic acid is released. Phosphonic acid released further binds to the metallic surface and thus improves the quality of the protective film.

Pt(II) 5,10,15,20-tetra(4-methoxy-phenyl)-porphyrin (PtTMeOPP) was used in the construction of new ion-selective sensors. The potentiometric response characteristics (slope and selectivity) of iodide and bromide-selective electrodes based on (PtTMeOPP) metalloporphyrin in o-nitrophenyloctylether (NPOE), dioctylphtalate (DOP) and dioctylsebacate (DOS) plasticized poly(vinyl chloride) membranes are compared. The best results were obtained for the membranes plasticized with DOP and NPOE. The sensors have linear responses with near-Nernstian slopes toward bromide and iodide ions and good selectivity. The membrane plasticized with NPOE was electrochemically characterized using the EIS method to determine its water absorption and the diffusion coefficient into the membrane.

Polyphosphoesters gained importance especially due to their use as flame retardants and as biocompatible and biodegradable materials for medicine and in the pharmaceutical industry. This paper presents the results obtained by our research group in the synthesis of polyphosphoesters by interfacial polycondensation. This reaction is rapid and irreversible polymerization at the interface between a phase containing one difunctional intermediate and another phase containing a complementary difunctional reactant. Different methods like liquid–liquid, vapor–liquid or solid

Improved ionic conductivity of solid polymer electrolytes (SPE) was achieved by adding polyaniline (PANI) in membrane formulation. SPE composite membranes contain: tris(4-hidroxybutylacrylate)-phosphate, polyphosphoester, lithium salts and small amount of PANI. The conductivity of membranes increases with PANI content and above a certain amount it decreases. The variation of the conductivity vs temperature is linear, characteristic for a thermally activated process. The activation energy for polymer matrix without PANI is 0.30 eV and 0.26 eV for polymer matrix with PANI. Conductivity enhancement in the composite polymer matrix is caused by the presence of PANI due to the increase in the concentration of free ions. PANI decreases the salt aggregation and as a consequence, the concentration of free ions was increased by improving dispersion of the lithium salt in membranes.

The aim of the present work was the study of phosphonic acids grafting on the surface of SnO2at different molar ratios. In this paper we describe the functionalization of SnO2surfaces with phosphonic acids RPO(OH)2. The surface modification process was achieved by using phenyl-phosphonic acid (PPA) and vinyl-phosphonic acid (VPA). The synthesized materials were investigated by using FT-IR, TGA (in air and in nitrogen), EDX, ESEM, and TEM methods. This synthetic approach has many advantages: films with optical quality and controlled thickness can be obtained using low temperatures and cheap raw materials, by using “green chemistry” synthetic routes. The hybrid materials have structures diversity and fascinating applications, attracting attention for a long time, due to their potential.

Two new series of solid polymer electrolytes (SPEs) based on phosphorus containing (co)polyesters (PPE) and Lithium triflate were obtained. PPEs are composed of phosphonate moeties (cyclohexyldichlorophosphonate (CHDP)) as linking agent and two diols: PEG (6000) and poly(tetramethylene glycol) (PTMG) in PPE I, and PEG (6000) and 4,4′-cyclohexylidenebisphenol (bisphenol Z, BZ) in PPE II. Polycondensation was carried out in solution in the presence of triethylamine (TEA) as scavenger of HCl side product (PPE I–IIa) and in the absence of any acid acceptor (PPE I–IIb). The Limiting Oxygen Index (LOI) and thermal analysis were performed both on polymers and membranes. The ionic conductivity of SPE membranes based on PPE-salt complexes, with various salt concentrations, was investigated at different temperature and ionic transference numbers were determined. Optimum composition was obtained for the polymer which contains in structure only alkyl units and 15% Lithium triflate.

Nanostructured polyaniline films have been electrochemically synthesized on passivated niobium substrate by potentiodynamic method in 0.5 and 1 mol L−1 H2SO4 solution and different aniline/acid molar ratios. The niobium oxide particles formed during passivation induce the nucleation of polyaniline nanofibers via adsorbed phenazine nucleates. The infrared spectra of polyaniline nanofibers showed the presence of vibrations attributed to phenazine-units in the polymer chain which support the phenazine nucleates theory for polyaniline nanofiber growth. The morphology of polyaniline is also influenced by acid concentration and a branched structure consisting of polyaniline nanofibers with a mean diameter of 70 nm is observed for 1 mol L−1 sulfuric acid solution. The shape of the impedance spectra is controlled by charge transport through ion diffusion, with higher diffusion resistances for granular polyaniline. The capacitance increases with the polymer layer thickness and has higher values for nanofibrilar than for granular polyaniline.

Detection of biologic compounds in particular dopamine is usually based on the complexation between boronic acid groups and diols. For this reason the development of new sensors based on direct monitoring of boronic acid–diol complexation is attractive. A measurable electric response due to a change in the dopamine concentration can be achieved on electrodes modified with boronic groups. In this work a modified electrode has been obtained by electropolymerization of 3-aminophenylboronic acid in aqueous solutions on a preformed polyaniline layer electrochemically deposited on smooth and skeleton nickel electrodes. The modified electrodes have been tested as impedimetric sensors for the detection of dopamine in aqueous phosphate buffer at pH = 7.4. Both sensors gave a linear response for dopamine concentrations between 10−5 and 10−10 mol L−1. Poly(3-aminophenylboronic acid) modified skeleton nickel electrode has the advantage of an increased specific surface area, that lead to a high density of boronic acid groups and hence to a better sensitivity.

Polycondensation of arylphosphonic(phosphoric)dichlorides with various bisphenols was carried out using a new technique, namely, solid-liquid phase transfer catalysis. Potassium phosphate was used as the base. The synthesis of polyphosphonate by solid-liquid phase-transfer catalyst (PTC) polycondensation of phenylphosphonic dichloride with 4,4'-cyclohexylidenebisphenol is presented in detail. The structures of the polyphosphonates and flu- orine-polyphosphate were studied using this technique. The polymers were characterized by gel permeation chro- matography, Fourier transform infrared spectroscopy (FTIR), 1 H and 31 P nuclear magnetic resonance (NMR) spectroscopy, differential scanning calorimetry, and thermal analysis. Yields in the range of 80.2-86.5, and inherent viscosities in the range of 1.48-2.5 dL/g were obtained. High molecular weight polymers (Mn of ~11,800-21,600) were successfully prepared. The polymers were self-extinguishing and started losing weight at around 280-380 o C. The glass-transition temperatures of the polymers were detected in the range of 85-180 o C. The flammability was

New structures of polymers containing phosphorus in the main chain were prepared by interfacial polycondensation of phenylphosphonic dichloride with 4,4’-(1,3-phenylenediisopropylidene) bisphenol (bisphenol M) using two different methods: method I: gas–liquid interfacial polycondensation without an organic solvent and a catalyst; and method II: solid–liquid interfacial polycondensation using green solvents and without catalyst. The aim of this work was to apply these methodologies as eco-friendly and economical procedures for a green chemistry. The polymers were characterized by gel permeation chromatography (GPC), FT-IR, 1 H and 31 P-NMR spectroscopy, differential scanning calorimetry (DSC) and thermal analysis. Yields in the range of 88.0–90.0, and inherent viscosities in the range of 2.2–3.2 dl/g were obtained. High molecular weight polymers (57 600–114 400) have been successfully prepared. The polymers are self-extinguishing and begin to lose weight at around 300 °C. The flammability was investigated by measuring limiting oxygen index values (LOI).

UV-cured nanocomposite films were prepared from acrylic monomer and two types of nanomaterial: zirconium vinylphosphonate and zirconia, in the presence of a photoinitiator. The films were characterized by FTIR, SEM, and AFM. FTIR spectra showed the disappearance of band assigned to the CC group both of monomer and zirconium vinylphosphonate by polymerization and the presence of the phosphonate group in polymer. The influence of zirconium vinylphosphonate and zirconia content on thermooxidative degradation of polymeric films was studied by thermogravimetry. SEM and AFM images showed that nanomaterials are dispersed in polymer matrix with no macroscopic phase separation. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

The author group was published incompletely in the original publication. The complete author group is given in this erratum. The original article has been corrected.

The effect of temperature on the electrochemical oxidative polymerization of aniline and on the electrochemical properties of the resulting polyaniline (PANI) film was studied. The electrochemical deposition of PANI has been carried out on platinum at different temperatures. Three different films (PANI-25, PANI-40 and PANI-60) have been prepared at 25, 40 and 60 °C by electrochemical polymerization and characterized by cyclic voltammetry and electrochemical impedance spectroscopy. Increasing the synthesis temperature leads to an increase of the polyaniline films thickness from 0.4 to 0.9 μm and, respectively, 1.1 μm, associated with an increase of the films capacitances from 3 × 10−2 F cm−2 to 7 × 10−2 F cm−2 and 10 × 10−2 F cm−2. The impedance measurements showed that only PANI-25 and PANI-40 exist in the conductive state over a large potential window, while PANI-60 has an intermediate behavior at low and high electrode potentials.

A method for preparing organic–inorganic hybrids containing organophosphorus compounds, silica, and polyaniline (PANI) was developed using sol–gel technique. This method allows the in situ synthesis of organic–inorganic hybrids by reacting tetraethoxysilane (TEOS), aniline, initiator, organophosphorus compound in formic acid. The formic acid has multiple functions: as solvent and acidic media for polymerization of aniline and reagent for sol–gel process. The use of an organophosphorus compound as coupling agent and the introduction of a conductive polymer in silica matrix was investigated.

The reaction of phenylphosphonic dichloride with 4,4′-cyclohexylidenebisphenol by a gas–liquid interfacial polycondensation was investigated. The design of experiments (DoE) method is used for determination of the best reaction conditions. The correlation of simultaneous influence of the parameters (reaction time, reaction temperature, alkaline medium, reagents molar ratio) on yield and inherent viscosity was studied.

Samples of an organic–inorganic hybrid were prepared by solvolysis and polycondensation in formic acid of tetraethoxysilane and diethylbenzyl phosphonate, simultaneous with the oxidative polymerization of aniline. The thermal behavior of the samples in dynamic air atmosphere and non-isothermal conditions was determined by a coupled thermogravimetric/evolved gas analysis. Two significant thermal events were established: the elimination from the polymeric matrix of low mass molecules, respectively the thermooxidative degradation of the organic part of the matrix. The kinetic analysis was performed with the Flynn-Wall-Ozawa, Friedman and modified Non-Parametric-Kinetic methods. Only the last one allowed an objective analysis of the first process as a process of two simultaneous thermally induced phenomena with the kinetic functions of the type αm(1 − α)n.

Polyaniline was obtained by oxidizing aniline in hydrochloric acid media with ammonium peroxidisulfate as oxidizing agent. Molar ratio aniline/oxidant was 1 and ani- line/acid ratio: ,a t-5 and 400 C, respectively, 800 mL water. The both compounds were studied using two different experimental strategies: the coupled TG-EGA (FTIR) tech- nique by decomposition in dynamic air atmosphere and the kinetic analysis of TG data obtained at four heating rates (5, 7, 10 and 15 K min -1 ). The kinetic analysis of the TG non-isothermal data was performed with the Flynn-Wall- Ozawa, Friedman's, and modified non-parametric kinetic (NPK) methods. By means of the coupled techniques spec- troscopic arguments on the reaction mechanism were obtained, i.e. the oxidative degradation of the quinoine ring as the first step. The values of the activation energy by the three used methods are in good agreements. According to the NPK method, the termodegradation process consist in physical (diffusion) and chemical steps.

Polyphosphonates, polyphosphates, polyarylazophosphonates and polyarylazophosphates were synthesized by a new alternative to the classical phase transfer catalysis, respectively, the modified inverse phase transfer catalysis (IPTC) polycondensation of various phenylphosphonic (phosphoric) dichlorides (phenylphosphonic dichloride, phenylphosphoric dichloride, p-chlorophenylphosphoric dichloride) with bisphenols: bisphenol A, tetrabromobisphenol A, bis-(4-hydroxyphenyl)methane (bisphenol F), 4,4′-dihydroxyazobenzene. The polymers were characterized by infrared spectroscopy and magnetic resonance (1H-NMR, 31P-NMR, 13C-NMR) spectroscopy. Yields in the range of 63.5–85% and molecular weights (M w) of ~2,000–8,200 g mol−1 were obtained. Polyphosphonates were stable up 210–270 °C and polyphosphates up 190–220 °C in air atmosphere. For a correct estimation of the thermal behavior of similar compounds, a kinetic analysis using a modified version of Non Parametric Kinetic method for representative polyphosphonate and polyphosphate was realized. The studies made on the hydrolytic degradation of the synthesized polyphosphates show that the most stable polymer under alkali-catalyzed degradation is the polyphosphate obtained by IPTC of phenylphosphoric dichloride and bisphenol A.

Processable conducting materials for large-scale utilization were prepared by mechanical mixing of polyaniline (PANI) paste and commercially acrylic resin. Doped PANI with organic phosphorus acid was synthesized. These blends can be used for the production of semiconductive paints with good corrosion resistance. By mixing doped PANI with commercially acrylic acid (SMP 63 AZUR SA) hard semiconducting and low elastic films are obtain. The effect of four variables was simultaneously studied: PANI (concentration), stirring speed (ST), mixing time (MT), dispersing agent (DA). Due to the number of variables, a factorial-design was chosen in order to reduce the number of experiments required in order to obtain coatings with high hardness and elasticity and semiconductive behavior. The results indicated that the influences of control factors decrease in order: PANI (concentration), mixing time (MT), dispersing agent (DA) and stirring speed (ST). From the studied variables, the resistance is significantly influenced by the two control factors PANI and MT.

The reaction of phenylphosphonic dichloride with bisphenol A (BA) by inverse phase transfer catalysis method was investigated. The design of experiments method was applied to establish the correlation between the simultaneous influence of the parameters (alkaline medium, reaction temperature, reagents molar ratio, and stirring speed) on yield and inherent viscosity, as well as for identifying the best reaction conditions. This method allows the simultaneous variation of control factors, thus decreasing the number of experiments in the polyphosphate synthesis. The process control factors used in this study were reagents' molar ratio, base concentration, and reaction temperature. The experimental results using 20 and 14 process runs, lead to an optimal synthesis procedure. The optimal values for yield and viscosity were obtained at molar ratio = 1, base concentration = 1.1 M, and reaction temperature = −12°C and have been experimentally verified with a series of four runs. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers

Polyaniline (PANI) is one of the intrinsic semiconductive polymers and shows some useful properties: high conductivity, transparency for the red and violet domain of spectrum, good elasticity and processability, superficial tension and chemical, photochemical and electrochemical behaviour. A PANI primer coat has been developed to act as an active electronic barrier to corrosion. When overlaid with a conventional durable topcoat, the coating has been shown to protect steel against salt, pollutants and other harsh environments. Dry blends were prepared by blending the powders of doped PANI and the host polymer, a commercial melamine-formaldehyde resin AZAMIN M514 in a mixer. The hardness, elasticity, resistance and protective behaviour of melamine-formaldehyde resin films were determined. The protective behaviour of obtained melamine-formaldehyde resin blend was evaluated from quantity of Fe (II) released by the coated carbon steel samples (exposed area 1-0 cm -2 ) immersed for 1 month in 50 mL 3·5%NaCl solutions. The prepared coatings protect substrate from corrosion by stabilising the oxide layer formed on the metal surface and thus prevent the metal dissolution process. An optimum formulation of melamine-formaldehyde resin coatings with 5 wt-% doped PANI exhibits good protective behaviour.

The aminophosphonate styrene–divinylbenzene–silica hybrid materials are obtained in two step reactions: synthesis of alkoxysilane containing polymer precursors and preparation of organic/inorganic ...

Ultraviolet (UV) curing is an important and widely used surface technology for coatings. The curable formulations containing: monomer: epoxydiacrylate, photoinitiating system: 4-methoxy-benzoyldiphenylphosphine oxide/2-hydroxy-2-methyl-1-phenyl-propan-1-one, additive reactive: tertiary amine, and inorganic thermoresistant pigments: white (TiO 2 ) and blue (Al 2 O 3 -Cr 2 O 3 ), were cured like films by UV exposure. A series of experiments was carried out in order to optimise the photoinitiator ratios in photoinitiating system, and pigment content in the photocurable formulation. Films with enhanced mechanical properties (pendulum hardness, scratch resistance), high resistance at solvents and good appearance were developed. In order to provide adequate hiding power of the pigmented formulation, the pigment content has been chosen in the range 5-15%. Up to 15% pigment content may affect the efficiency of photoinitiator. The polymerisation efficiency (conversion and polymerisation rates) of photoinitiating systems in pigmented formulations was performed by differential scanning photocalorimetry (photo DSC) in comparison with the original systems without pigments.

Direct, efficient, organic solvent- and catalyst-free synthesis of a series of polyphosphates was accomplished. The reaction involved a gas-liquid interfacial polycondensation between arylphosphoric dichlorides and bisphenol A. The polyphosphates were characterized by IR, 1H NMR, 31P NMR, inherent viscosity, thermal analysis, and molar mass. Yields in the range 70-90 % and inherent viscosities in the range 0.30-0.40 dl/g were obtained. The thermal stability of the polyphosphates was investigated by using thermogravimetry.

A novel synthesis of polyphosphates by inverse phase transfer catalysis (IPTC) was investigated. The reaction of methylphosphoric dichloride (MPD) and sodium salt of bisphenol A (BA) in two-phase H 2 O/CH 2 Cl 2 medium under IPTC is presented and the results are evaluated by the yield and inherent viscosity values. The biphasic medium does not require rigorous stirring. The polyphosphate was characterized by IR, 1 H NMR, 31 P NMR, inherent viscosity, thermal analysis, and molar mass. Pyridine (Py), pyridine-oxide (PNO) and 4-dimethylamino-pyridine (DMAP) were used as the inverse phase transfer catalysts. DMAP was found to be the best catalyst.

A styrene-divinylbenzene copolymer functionalized with aldehyde was prepared under phase transfer catalyzed (PTC) conditions. A statistical method for the calculation of the degree of functionalization with aldehyde groups is proposed. The degree of functionalization with aldehyde groups is relatively high. Styrene-divinylbenzene polymers functionalized with benzaldehyde groups were used in Wittig-Horner reaction, in order to introduce double bonds on polymers. The reactions were carried out using PTC method, solid-liquid-solid (s-l-s) (K2CO3, tetrahydrofuran, tetraethylammonium iodide) system. Phase transfer catalyzed reactions are often more easily and cheaply carried out than conventional method and they are therefore of particular interest.

Preparation and characterization of polyaniline (PANI) doped with anions containing phosphorus was investigated with the help of various technique. The chemical polymerization of aniline was carried out in acid media containing different anions of organic phosphorus acid with the use of ammonium peroxidisulfate as oxidant agent. The highest yield was observed in the case of styrilphosphonic acid. The conductivity increased in the following order: phenylphosphinic acid

Wastewaters generated by electroplating, Industry of Pigments, Tannins, etc. contain Cr(VI).The removal of Cr(VI)from wastewaters is necessary due to its toxicity; the admissible concentration being 10 ppm.This work studies quantitatively and qualitatively the possibility of treating waste waters that have a concentration of 0.1 g/l Cr(VI), by using DVB gels coated with Pani films.The Pani films were applied on the DVB's surface both by polymerization of aniline in acid medium, using ammonium peroxodisulphate as the oxidizing agent and by treating the DVB gels with Pani solutions in N,N-dimethylformamide.During reaction, the reduction rate of Cr(VI)decreases because the Pani films are degrading. This degradation is generated by over-oxidation, phenomenon that leads to a series of secondary hydrolysable products.

Polyphosphates were synthesized by base promoted liquid-vapor polycondensation of cyclohexylphosphoric dichloride with bisphenol A. The effects of temperature, reaction time, base concentration and molar ratio of reagents on yield, inherent viscosity and molecular weight of the obtained polymer were studied. A second order, central composite, rotatable experimental design was used to find domain experimental field for optimal yields and high inherent viscosities.

In contrast with other conductive polymers with metallic behavior, polyaniline(Pani)is readily prepared in aqueous acid solution, and stable in air and water. The study of thermal stability of Pani is very important for film preparation and processability. The effect of Styrene-2%Divinylbenzene gels(DVB)and synthesis conditions on the conductivity and thermal stability of the PAni-DVB have been investigated. It was established a correlations between synthesis conditions and thermal stability of PANI-DVB gels.

The polyaniline(PAni)coating was electrochemically deposited on nickel skeleton electrode and nickel foil by potential sweep between − 0.2 V and 1.2 V/SCE, with a scan rate of 20 mV s−1; acid aqueous solutions containing 0.027 mol L−1aniline in 1 mol L−1sulphuric acid were used. The PAni film was studied by IR Spectroscopy, UV-VIS Absorption, Scanning Electron Microscopy, X-Ray Diffraction and Cyclic Voltammetry. The X-Ray studies suggest that the PAni films present a good cristalinity, as well as high molecular weight, possible high or intermediate crosslinked.