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In the present study, a novel electrically conductive polypyrrole–titanium(iv)sulphosalicylophosphate (PPy–TSCP) cation exchange nanocomposite was synthesized by an in situ chemical oxidative polymerization of pyrrole in the presence of titanium(iv)sulphosalicylophosphate (TSCP). The PPy–TSCP cation exchange nanocomposite was characterized by various instrumentation techniques such as FTIR, FE-SEM, XRD, TGA, DTA, DTG and EDXA. The composite exhibited good ion-exchange capacity (IEC) (2.10 meq g−1) as well as electrical conductivity (0.756 S cm−1) and isothermal stability in terms of DC electrical conductivity retention under ambient conditions up to 100 °C. The PPy–TSCP cation exchange nanocomposite based sensor was fabricated for the detection of acetaldehyde vapours, and it was found that the resistivity of the nanocomposite increases on exposure to a high concentration of acetaldehyde vapors at room temperature (25 °C). The rate of reaction for acetaldehyde vapour sensing on PPy–TSCP was observed to be first order. [ABSTRACT FROM AUTHOR]

Electrically conductive Polypyrrole-zirconium(IV)selenoiodate (PPy/ZSI) cation exchange nanocomposite have been synthesized by chemical oxidative polymerization of polypyrrole (PPy) in the presence of zirconium(IV)selenoiodate (ZSI) by sol-gel method. The formation of PPy/ZSI nanocomposite was characterized by fourier transform infra-red spectroscopy (FTIR), x-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive x-ray (EDX) and thermogravimetric analysis (TGA). The ion exchange capacity (IEC) and electrical conductivity of the nanocomposite was found to be 2.49 meq/g and 0.436 S/cm respectively. The nanocomposite showed appreciable isothermal stability in terms of DC electrical conductivity retention under ambient condition up to 130 °C. In addition, the cation exchange nanocomposite based sensor for detection of formaldehyde vapors was fabricated at room temperature. It was revealed that the resistivity of the nanocomposite increases on exposure to higher percent concentration of formaldehyde at room temperature (25 °C), also the sensor exhibited good reversible response towards formaldehyde vapors ranging from 5 to 7%. The present study may serve as a basis for designing other smart materials for formaldehyde sensors. [ABSTRACT FROM AUTHOR]

Abstract: Electrically conductive poly(3-methythiophene) cerium(IV)phosphate cation exchange nanocomposites have been synthesized for the first time by in situ chemical oxidative polymerization of 3-methythiophene in the presence of cerium(IV)phosphate. FTIR, SEM, TEM and XRD analysis were used to characterize P3MTh cerium(IV)phosphate cation exchange nanocomposites. The characterization results confirmed that there is a strong interaction between poly(3-methythiophene) and cerium(IV)phosphate particles. The thermal behavior of poly(3-methythiophene), cerium(IV)phosphate and poly(3-methythiophene) cerium(IV)phosphate nanocomposite were also investigated by thermogravimetric analysis (TGA), differential thermal analysis (DTA) and differential thermal gravimetry (DTG) at heating rate 10°Cmin−1 under nitrogen atmosphere and the P3MTh cerium(IV)phosphate nanocomposite was found thermally more stable than pure P3MTh. Isothermal stability of P3MTh and P3MTh cerium(IV)phosphate nanocomposite in terms of direct-current electrical conductivity retention was also studied in ambient air. The P3MTh cerium(IV)phosphate nanocomposite showed better ion-exchange capacity, electrical conductivity and isothermal stability in terms of direct-current electrical conductivity retention under ambient condition than pure poly(3-methythiophene). [Copyright &y& Elsevier]

Abstract: Electrically conductive poly(3-methythiophene)-titanium(IV)molybdophosphate (P3MTh–TMP) cation exchange nanocomposites have been synthesized for the first time by in situ chemical oxidative polymerization of 3-methythiophene (3MTh) in the presence of titanium(IV)molybdophosphate (TMP). Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) analysis, thermogravimetric analysis (TGA) and elemental analysis were used to characterize P3MTh–TMP cation exchange nanocomposites. The characterization results confirmed that there is a strong interaction between P3MTh and TMP particles and the nanocomposites showed higher thermal stability than pure P3MTh. The composite showed good ion-exchange capacity, electrical conductivity and isothermal stability in terms of DC electrical conductivity retention under ambient condition below 100°C. A cation exchange nanocomposite based sensor was fabricated for the detection of aqueous ammonia, it was found that the resistivity of the nanocomposites increases on exposure to ammonia at room temperature (25°C) and there showed a linear relationship between the responses and the concentration of ammonia. [Copyright &y& Elsevier]

Abstract: Electrically conductive Poly-o-toluidine–titanium(IV)phosphate (POT–TiP) cation exchange nanocomposite was synthesized by sol–gel mixing of organic polymer (Poly-o-toluidine) into inorganic precipitate of titanium(IV)phosphate (TiP). The material was characterized by using transmission electron microscopy (TEM), X-ray diffraction analysis (XRD), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). The humidity sensing response of the nanocomposite was examined. It was found that the conductivity varied according to low humidity to high humidity. The composite showed good humidity response, ion-exchange capacity and electrical conductivity. Poly-o-toludine–TiP nanocomposite was also used to study electrical conductivity under isothermal conditions in the temperature range 50–130°C. The composite was found stable under ambient conditions below 90°C in terms of DC electrical conductivity retention. These studies suggest that the cation exchange nanocomposite could be a good sensing material for humidity. [Copyright &y& Elsevier]

Abstract: Newly developed organic–inorganic cation-exchange materials poly-o-anisidine and poly-o-toluidine Sn(IV) tungstate composites were synthesized by a modified sol–gel technique by incorporating Sn(IV) tungstate precipitate with the matrix of electrical conducting poly-o-anisidine and poly-o-toluidine. The materials showed good ion-exchange behavior and were used successfully in the separation of metal ions. The conductivity of the composites was measured by 4-in-line-probe DC electrical conductivity measuring device and was found within the range of 10−4–10−2 S/cm. The DC electrical conductivity of both composite materials was found stable up to 140°C under ambient conditions. The conductivity was at the border of metallic and semiconductor region. [Copyright &y& Elsevier]

Abstract: Composites are 21st century material used to meet the demand of improved materials and possess a combination of several desirable properties. Present study focussed on the conducting behavior of ‘polymeric–inorganic’ nanocomposite of conducting polymer polyaniline and polypyrrole. ‘Polymeric–inorganic’ nanocomposite cation-exchangers, i.e., polyaniline zirconium titanium phosphate (PANI-ZTP) and polypyrrole zirconium titanium phosphate (PPy-ZTP), were synthesized via sol–gel mixing of electrical conducting polymers into the matrices of inorganic precipitate of zirconium titanium phosphate (ZTP) having excellent ion exchange properties. The proposed nanocomposite possessed DC electrical conductivity in the semi-conducting range, i.e., 10−5–10−3 Scm−1. The stability in terms of DC electrical conductivity retention was also studied in an oxidative environment by two slightly different techniques viz. isothermal and cyclic techniques. The DC electrical conductivity of composite material was found stable upto 110°C under ambient conditions. [Copyright &y& Elsevier]

Abstract: In this study, the electrically conducting polyaniline–titanium(IV)phosphate (PANI–TiP) cation exchange nanocomposite was synthesized by sol–gel method. The cation exchange nanocomposite based sensor for detection of ammonia vapors was developed at room temperature. It was revealed that the sensor showed good reversible response towards ammonia vapors ranging from 3 to 6%. It was found that the sensor with p-toluene sulphonic acid (p-TSA) doped exhibited higher sensing response than hydrochloric acid doped. This sensor has detection limit ≤1% ammonia. The response of resistivity changes of the cation exchange nanocomposite on exposure to different concentrations of ammonia vapors shows its utility as a sensing material. These studies suggest that the cation exchange nanocomposite could be a good material for ammonia sensor at room temperature. [Copyright &y& Elsevier]

Abstract: Electrically conductive composite of polyaniline–titanium(IV)phosphate (PANI–TiP) was synthesized by sol–gel method. The obtained composite was characterized by using Fourier transform infra red spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and thermogravimetric analysis (TGA). The composite showed good ion-exchange capacity and isothermal stability in terms of DC electrical conductivity retention at an ambient conditions below 100°C. The composite material was investigated as alcohol vapors sensor and compared with blank polyaniline. The results showed that the composite was more selective and sensitive towards methanol vapors. [ABSTRACT FROM AUTHOR]

Polypyrrole has emerged as one of the highly pursued conducting polymers owing to its high electrical conductivity and good environmental stability. In spite of its excellent electrical properties, the chemical and thermal stability and processability are not very satisfactory. The incorporation of a polymer material into an inorganic ion-exchanger provides a high class of hybrid ion-exchangers with enhanced ion-exchange properties, high reproducibility, high stability, and good selectivity for heavy metals. A novel organic–inorganic composite-polypyrrole zirconium titanium phosphate has been synthesized using zirconium titanium phosphate, which is an advanced inorganic ion-exchange material with the qualities listed above. The physicochemical properties of this composite material are characterized by X-ray, TGA–DTA, AAS, FTIR, SEM, and TEM. The ion-exchange capacity, pH titrations, elution, and chemical stability were determined to study ion-exchange properties of the material. Distribution studies for various metal ions revealed that the nano-composite is highly selective for Th(IV). An ion-selective membrane electrode was fabricated using this material for the determination of Th(IV) ions in solutions. The analytical utility of this electrode was established by employing it as an indicator electrode in electrometric titrations. [ABSTRACT FROM AUTHOR]

Abstract: Conductive fibers based on polyaniline (PANI) and polyacrylonitrile (PAN) were obtained by stirring with magnetic bar. This research was conducted to investigate conducting fibers of polyaniline:polyacrylonitrile (PANI:PAN) composite with different weight ratios of aniline in PAN matrix. The fibers were prepared by stirring process. The best conductivity behavior of the fibers was obtained with 5mL of aniline. The fibers obtained were characterized using Fourier-transform infrared spectra (FTIR), scanning electron microscopy (SEM) and thermogravimetric analysis (TGA). The variation of electrical conductivity with different type doping agents (HCl, H2SO4 and HClO4) and the stability in terms of DC electrical conductivity retention was studied in an oxidative environment by isothermal characteristics. [Copyright &y& Elsevier]

Abstract: A nano-composite inomeric poly-o-anisidine Sn(IV) phosphate [POASn(IV)P] was prepared via sol–gel mixing of an electrically conducting organic polymer, poly-o-anisidine with the matrices of inorganic precipitate of Sn(IV) phosphate. The physico-chemical properties of the material were determined using AAS, CHN elemental analysis, UV–vis spectrophotometry, FTIR, TGA–DTA, TEM, XRD and SEM studies. Electrical conductivity studies were carried out by four in-line probe DC electrical conductivity measuring instrument. The conductivity was found within the range of semiconductor region (10−3 to 10−2 S/cm). Isothermal and cyclic techniques were also used to understand the stability in terms of DC electrical conductivity retention. [Copyright &y& Elsevier]

Abstract: An advanced organic–inorganic cation exchange material poly-o-toluidine Th(IV) phosphate nano-composite was synthesized by a modified sol–gel technique by incorporating Th(IV) phosphate precipitate with the matrix of poly-o-toluidine. The material showed good ion-exchange behavior and used successfully in separation of metal ions. The conductivity of the composite was found within the range of 10−2 to 10−3 S/cm; measured by 4-in-line-probe dc electrical conductivity measuring technique. The conductivity is at the border of metallic and semiconductor region. Ion-exchange kinetics for few divalent metal ions was evaluated by particle diffusion-controlled ion-exchange phenomenon at four different temperatures. The particle diffusion mechanism is confirmed by the linear τ (dimensionless time parameter) versus t (time) plots. The exchange processes thus controlled by the diffusion within the exchanger particle for the systems studies herein. Some physical parameters like self-diffusion coefficient (D 0), energy of activation (E a) and entropy of activation (ΔS 0) have been evaluated under conditions favoring a particle diffusion-controlled mechanism. [Copyright &y& Elsevier]

Abstract: ‘Polymeric–inorganic’ composite type of cation-exchanger ‘polypyrrole Th(IV) phosphate’ was prepared by mixing polypyrrole into fibrous inorganic precipitate of Th(IV) phosphate. This type of composite possesses a new class of hybrid ion-exchangers with good ion-exchange capacity (I.E.C.), higher stability, reproducibility and selectivity for heavy metals. The physicochemical properties of the material were determined using AAS, CHN elemental analysis, ICP-MS, UV-VIS spectrophotometry, FTIR, thermogravimetric analyses-differential thermal analysis (TGA-DTA), XRD and SEM studies. Ion-exchange capacity, pH-titrations, elution and distribution behavior etc. were also carried out to characterize the material. On the basis of distribution studies, the material was found to be highly selective for Pb(II), a heavy metal pollutant in the environment. Its selectivity was examined by achieving some important binary separations like Pb(II)–Zn(II), Pb(II)–Ni(II), Pb(II)–Cu(II) and Pb(II)–Cd(II) on its column that indicate its utility in environmental pollution control in one-way or other. This electroactive material also showed the DC electrical conductivity in the range of 10−6 to 10−4 Scm−1. A new heterogeneous precipitate based selective ion-sensitive membrane electrode was developed by using this composite cation-exchanger for the determination of Pb(II) ions in solutions. The analytical utility of this electrode was established by employing it as an indicator electrode in electrometric titrations. [Copyright &y& Elsevier]

An electrically conducting `organic–inorganic'' crystalline type composite cation-exchange material, the polypyrrole/polyantimonic acid system was prepared by incorporating polypyrrole into an inorganic precipitate of polyantimonic acid. The temperature dependence of the electrical conductivity of this composite system was measured on compressed pellets by using a 4-in-line-probe dc electrical conductivity-measuring instrument. The conductivity values lie in the semiconductor region, i.e., they are of the order of 10-5–10-4 S cm-1 and follow the Arrhenius equation. The energy of activation of electrical conduction was also calculated. This system also possessed an improved ion-exchange capacity, high chemical and thermal stabilities, reproducibility and selectivity for some specific metal ions. Kinetic studies of exchange for some divalent metal ions of alkaline earths and transition metals were carried out under conditions favoring a particle diffusion-controlled ion-exchange phenomenon and some physical parameters such as the self diffusion coefficient D0, the energy of activation Ea and the entropy of activation ΔS* were determined. [Copyright &y& Elsevier]

The current study was conducted to explore the physicochemical characteristics, light and heavy metal concentrations in drinking water of the selected area of Lower Dir, Pakistan. In the study area, no such study about the assessment of drinking water quality has been carried out. The people of Lower Dir are unaware about the quality of water and adverse impacts of contaminated water. The research work will provide base for the awareness campaign regarding the importance of pure and safe drinking water quality.. For this purposes, the water samples (n=22) were collected and analyzed for various parameters. Among the physical parameters the pH, dissolved oxygen (DO), electrical conductivity (EC), salinity and temperature, while in - chemical parameters the alkalinity, total dissolved solids (TDS), hardness, chlorides (Cl ), and sulfates were determined. Light metals such as magnesium (Mg+2), calcium (Ca+2), sodium (Na+2), and potassium (K+) and heavy metals included lead (Pb), chromium (Cr), nickel (Ni), and zinc (Zn) were analyzed in the collected samples. The results showed that all the parameters were within the permissible limits set by World Health Organization (WHO) and Pakistan Environmental Protection Agency (Pak-EPA) except hardness (351.44 mg/L). The light metals were within the permissible limit except Mg (308.60 mg/L) that exceeded the permissible limits of WHO and Pak-EPA, while Ca (53.71 mg/L) exceeded the permissible limit of WHO. The heavy metal results showed that all the metals were within permissible limit except Cr (0.18 mg/L) and Pb (0.04 mg/L). The health risk assessment like Average Daily Dose (ADD) and Hazard Quotient (HQ) were calculated for heavy metals. All heavy metals in drinking water samples indicated no health risk (CDI and HQ<1). [ABSTRACT FROM AUTHOR]

The current study was conducted to explore the physicochemical characteristics, light and heavy metal concentrations in drinking water of the selected area of Lower Dir, Pakistan. In the study area, no such study about the assessment of drinking water quality has been carried out. The people of Lower Dir are unaware about the quality of water and adverse impacts of contaminated water. The research work will provide base for the awareness campaign regarding the importance of pure and safe drinking water quality. For this purposes, the water samples (n=22) were collected and analyzed for various parameters. Among the physical parameters the pH, dissolved oxygen (DO), electrical conductivity (EC), salinity and temperature, while in chemical parameters the alkalinity, total dissolved solids (TDS), hardness, chlorides (Cl-), and sulfates were determined. Light metals such as magnesium (Mg+2), calcium (Ca+2), sodium (Na+), and potassium (K+) and heavy metals included lead (Pb), chromium (Cr), nickel (Ni), and zinc (Zn) were analyzed in the collected samples. The results showed that all the parameters were within the permissible limits set by World Health Organization (WHO) and Pakistan Environmental Protection Agency (Pak-EPA) except hardness (351.44 mg/L). The light metals were within the permissible limit except Mg+2 (308.60 mg/L) that exceeded the permissible limits of WHO and Pak-EPA, while Ca+2 (53.71 mg/L) exceeded the permissible limit of WHO. The heavy metal results showed that all the metals were within permissible limit except Cr (0.18 mg/L) and Pb (0.04 mg/L). The health risk assessment like Average Daily Dose (ADD) and Hazard Quotient (HQ) were calculated for heavy metals. All heavy metals in drinking water samples indicated no health risk (CDI and HQ<1). [ABSTRACT FROM AUTHOR]

Electrically conductive polycarbazole–titaniumdioxide nanocomposite(PCz/TiO2) have been synthesized for the first time byin situ chemical oxidative polymerization of carbazole (Cz) in thepresence of titanium dioxide (TiO2) nanoparticles. FTIR,SEM, TEM, XRD, TGA, and DTA were used to characterize PCz/TiO2nanocomposites. The characterization results confirmed thatthere is a strong interaction between PCz and TiO2nanoparticlesand the nanocomposites showed higher thermal stability than pure PCz.The composite showed electrical conductivity and isothermal stabilityin terms of DC electrical conductivity retention under ambient conditionbelow 100 °C. A nanocomposite-based sensor was fabricated forthe detection of aqueous ammonia, it was found that the resistivityof the nanocomposites increases on exposure to ammonia at room temperature(25 °C), and it showed a linear relationship between the responsesand the concentration of ammonia. The comperative antimicrobial activitiesof PCz, its PCz/TiO2-7 nanocomposite and ciprofloxacindrug with different bacteria have also been studied. [ABSTRACT FROM AUTHOR]