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A new electrochemical analysis based on ß-cyclodextrin (ß-CD) was developed for penicillin V (Peni-V) using polyaniline as a conducting polymer.

The preparation of modified electrode involves the incorporation of β-CD with membrane of polyaniline. Polyaniline, incorporating β-CD, was prepared by electrochemical polymerization method in a medium of hypochloride. Cyclic voltammetry and electrochemical impedance have been used to characterize this sensor. The detection and the kinetic study of modified platinum electrode are evaluated.

Results clearly indicate that β-CDs interfere with the polymerization mechanism with an inhibition factor. The inclusion phenomenon of β-CDs has been studied and applied to detect Peni-V. The principle of this electrochemical sensor is based on the chemical properties of β-CD, which were studied using the cyclic voltammetric method and impedance spectroscopy. The electrochemical behavior of Peni-V at concentrations between 10^–8 and 10^–2 M was measured versus Ag/AgCl at pH 7.4 and 30°C in a phosphate alkaline buffer. Relationship of Peni-V concentration in logarithmic mathematical form with current in potentiometric method and with resistance in impedimetric method were obtained.

The present study showed that the Pt electrode modified with Polyaniline–β-CD was an excellent candidate for sensitive penicillin analysis. The proposed electroanalytical technique is rapid, simple and inexpensive.

A newly developed polyvinyl acetate (PVA) emulsion latex for adhesive has been prepared by the semicontinuous process using a newly developed octyl aldehyde sodium bisulphite‐potassium persulphate redox pair initiation system. In this work the amount of polyvinyl alcohol (PVA) as a protective colloid has been changed and it was found that only a little amount of (PVA) together with the newly developed adduct could cause a stable latex with excellent mechanical properties for bonding wood which favours this redox system in large industrial applictions. Also monodisperse latex particles with low polydispersity index can be prepared by using 1% PVA coupled with the newly developed redox system. Finally the developed latex has been incorporated and the corresponding shear strength were measured.

The purpose of this study is to undertake surface graft copolymerization of viscose fabric via altering its fibrous properties by using acrylic acid (AA) as a carboxyl-containing monomer and peroxydisulfate (PDS) in presence of ferrous sulfate as a novel redox pair for initiating grafting. The latter process acted as an energy-saving process with respect to the reduction in polymerization temperature and maximizing the graft yield %, in addition to rendering the grafted viscose fabrics dye-able with cationic dye (crystal violet), which has frequently no direct affinity to fix on fabric.

To make graft copolymerization more efficient and economic, the optimum conditions for graft copolymerization were established. The graft yield % was determined as a function of initiator, catalyst and monomer concentrations and the material to liquor ratio, in addition to polymerization time and temperatures. Metrological characterizations via Fourier transform infrared spectroscopy and scanning electron microscopy of topographic morphological surface change have also been established in comparison with the ungrafted samples.

The maximum graft yield of 70.6% is obtained at the following optimum conditions: monomer (150 % based on the weight of fabric), PDS (50 m mole), ferrous sulfate (80 m mole) and sulfuric acid (30 m mole) at 40° C for 1.5 h using a liquor ratio of 30. Remarkably, grafting with AA enabled a multifold upsurge in color strength, with improvements in the fastness properties of cationically dyed grafted viscose fabric measured on the blue scale in comparison with untreated viscose fabric.

The novelty addressed here is undertaken with studying the effect of altering the extent of grafting of poly (AA)-viscose graft copolymers expressed as graft yield % in addition to carboxyl contents on cationic dyeing of viscose fabric for the first time in the literature. Moreover, rendering the viscose fabrics after grafting is dye-able with cationic dye with high brilliance of shades, which has regularly no direct affinity to fix on this type of fabrics.

The purpose of this paper is to present a summary of development work made in technical centres and on the subsequent customer qualification of copper filled through holes and blind microvias.

Various copper deposition parameters were investigated in a small‐scale production line which was then extended to full‐scale production qualification in a horizontal conveyorised system. Samples of substrates with copper filled through holes were qualified at end‐user facilities.

The copper plating process may be used to replace an existing production process for printed circuit boards. The proposed system can give a more reliable result in terms of filling and technical capability for the produced substrate. Overall production cost savings are possible.

The technology is based on a copper plating electrolyte using a redox pair for copper replenishment. The results achieved depend on use of this system and on production equipment which can control the redox system and copper concentration within a tight range.

The paper shows how the use of a horizontal production system with redox copper replenishment can achieve filling of though holes and blind microvias with reduced surface plated copper thickness. Reduction in the use of copper saves both resources and also reduces production costs. The process is proposed as an alternative to existing paste plugging processes, which are both cost and labour intensive.

To improve the problems as the heavy burden of sewage treatment and environmental pollution caused by the traditional sodium hydrosulfite reduction dyeing of indigo, this study aims to carry out the direct electrochemical reduction dyeing for indigo with the eco-friendly Cu(II)/sodium borohydride reduction system under normal temperature and pressure conditions.

The electrochemical behavior of Cu(II)/sodium borohydride reduction system was investigated by cyclic voltammetry. And, the dyeing performance of the Cu(II)/sodium borohydride reduction system was developed by optimizing the concentration of copper sulfate in the anode electrolyte, applied voltage and reduction time via single-factor and orthogonal integrated analysis.

The dyeing performance of the Cu(II)/sodium borohydride reduction system is superior to that of the traditional reduction dyeing with sodium hydrosulfite. In the case of the optimized condition, the soaping fastness and dry/wet rubbing fastness of the dyed fabric in the two reduction dyeing processes were basically comparable, the K/S value of electrocatalytic reduction of indigo by Cu(II)/NaBH4 is 11.81, which is higher than that obtained by traditional sodium hydrosulfite reduction dyeing of indigo.

The innovative electrocatalytic reduction system applied herein uses sodium borohydride as the hydrogen source combined with Cu(II) complex as the catalyst, which can serve as a medium for electron transfer and active the dye molecule to make it easier to be reduced. The electrochemical dyeing strategy presented here provides a new idea to improve the reduction dyeing performance of indigo by sodium borohydride.

This paper aims to synthesise block copolymers (PPy-b-ENP) of pyrrole (Py) and ethoxylated nonyl phenols (ENP) via redox systems in presence of ceric ammonium nitrate (CAN) at room temperature. The initiating radical was formed on reducing organic compound which in turn initiated polymerisation to give diblock copolymers containing chain ends of ENPs and polypyrrole (Ppy). The effects of the concentration of Ce⁺⁴ salt, ENPs and Py on both the yield and electrical conductivities of corresponding polymers were studied.

In total, 0.1 M stock solution of CAN:100 ml 1 M HNO₃ was prepared freshly (7 ml HNO₃ dissolved in 100 ml water) and used in 50 ml of 0.1 M CAN solution (2.7438 g CAN dissolved in 50 ml nitric acid solution). The reducing compound (Py) was dissolved in water. Py and ENP were added slowly to the flask with vigorous stirring. The content of the flask was flushed with oxygen-free nitrogen. The resulting copolymers were characterised with spectroscopic methods like Fourier transform infrared spectroscopy and scanning electron microscope.

In this study, DMSO-slightly soluble Py copolymers were produced with ENPs. The conductivities of copolymers were found to be in the range of 10-1 to 10-4 S/cm. Soluble and processable conductive polymers were developed.

In this study, the water solubility of ENPs diminishes the conductivity of copolymer because of its surfactant structure. When the CAN/Py ratio was increased, PPys and copolymers with both higher yield and lower conductivity values were obtained. The results indicated that solubilities and the yield of the polymers synthesised in the presence of ENP have increased considerably. ENP caused degradative chain transfer reaction to become significant compared with bimolecular termination, so the yield decreased with increasing ENP concentration about 20 g/l. Results showed that yield of the copolymers strongly depends on Ce⁺⁴ concentrations while of copolymers were measured to be 10-3 S/cm.

PPy-b-ENP diblock copolymers were prepared with Ce⁺⁴ as an oxidation agent in a single step.

These slightly soluble and conductive copolymers may overcome difficulties in the applications of PPy homopolymers and open new application areas.

PPy-b-ENPs of lightly soluble (in DMSO) and conductive (10-2 S/cm) copolymers have been synthesised in one step. The results indicate that the surface of the copolymer is composed of well-distributed nanospheres with an average particle diameter of 35-400 nm.

The purpose of this study is to investigate the authors' previously prepared and fully characterized poly (methacrylamide)-chitosan nanoparticles (CNPs) graft copolymer having 50.2% graft yield with respect to flocculation efficiency for ferric laurate aqueous dispersions. This was done to compare the ability of the latter cheap, biodegradable and ecofriendly hybrid natural-synthetic polymeric substrate as a flocculant in comparison with higher cost, nonbiodegradable and harmful polyacrylamide as a well-known synthetic flocculant counterpart.

The graft copolymerization process was carried out at 450°Cfor 120 min using (1.0 g) CNPs, methacrylamide (1.5 g), 100 mmol/l potassium chromate and 80 mmol/l mandelic acid. Fourier transform infrared spectroscopy, thermogravimetric analysis, elemental analysis and specific viscosity were used to characterize and analyze the resultant copolymer. The flocculation efficiency was conferred in terms of transmittance % and weight removal %. The main factors influencing the flocculation process, such as flocculent dose, flocculation medium pH, stirring speed, flocculation temperature and grafting extent, were comprehensively discussed.

The flocculation efficiency of the prepared copolymers revealed the following findings: increased by increasing the flocculant dose, pH, temperature and stirring speed to a maximum values denoted at 30 ppm, 6.0, 30°C and 50 r/min, respectively, then decreased thereafter; increased by increasing the extent of grafting within the range studied; showed a comparable flocculation efficiency in comparison with polyacrylamide as a synthetic polymeric flocculent; and, finally, a preliminary bridging mechanism representing the attraction between the anionic suspended particles ferric laurate and cationic poly (MAam)-CNPs graft copolymer has been projected.

The advancement addressed here is undertaken with using the authors’ poly (MAam)-CNPs graft copolymers having different extent of grafting (a point which is not cited in the literature especially for the authors’ prepared copolymer) as a hybrid natural-synthetic polymeric substrate as a flocculant for ferric laurate aqueous dispersions in comparison with the high cost and nondegradable polyacrylamide synthetic flocculant.

Details the preparation of emulsion copolymerization of styrene (St)‐vinylacetate (VAc) with different molar ratio 33:67(A1), 50:50(A2) and 67:33(A3) using redox initiator system (k2S208/NaHS03) and investigates their film forming. Finds that the drying film characterization took on a brittle property which is attributed to the nature of styrene polymers. Explains that molar ratio 67:33 from butyl acrylate (BuA‐VAc) and vinyl acetate (B1, B2 and B3) in the presence of pluronic F87 was chosen as the coemulsifier as it gives good transparent and elastic film properties but has a tacky character owing to the nature of butyl acrylate polymer. Shows that styrene‐butylacrylate (St‐BuA) 67:33 molar ratio(C) has high conversion and a solid content of 51 per cent, and its film forming gives a transparent sheet that dries within 45 minutes. Notes that incorporation of these latices into interior and exterior coatings gives good characterization (hardness, ductility, adhesion and washability of 4,042 cycles) compared with the standard specifications for evaluation of latex paint.

This paper aims to investigate the electrochromic (EC) properties of poly(triphenylamine alkyl ether) and poly(triphenylamine aryl ether) in two different electrolyte solution to study the resistive switching behaviour of acid-doped poly(triphenylamine alkyl ether).

By Buchwald–Hartwig coupling reaction, two novel poly[N-p-phenoxy-N-[4-[2-(2-methoxyethoxy)ethoxy]ethoxy]triphenylamineandpoly[N,N-bis(4-phenoxy)]triphenylamine were synthesized from 4-phenoxyaniline and two dibromo aromatic compounds, 1,2-bis[β,β′-(p-bromophenoxy)ethoxy]ethane and bis(4-bromophenyl) ether.

Poly(triphenylamine alkyl ether) displayed excellent EC characteristics, with a coloration change from a colourless neutral state to light blue and red oxidized states, while poly(triphenylamine aryl ether) showed coloration a change from a colourless neutral state to light blue oxidized state in tetrabutylammonium perchlorate electrolyte solution. Moreover, p-toluenesulfonic acid-doped poly(triphenylamine alkyl ether) exhibited a non-volatile bistable resistive switching behaviour with a high high-conductivity/low-conductivity ratio of up to 104, long retention time exceeding 2.5 × 10³ s and the switching threshold voltage was also lower than −2V.

In this paper, the non-volatile bistable resistive switching behaviour of acid-dopedpoly(triphenylamine alkyl ether) was in accordance with the molar ratio of 1:1. The effects of different molar ratios remained to be studied.

Poly(triphenylamine ether)s may find optoelectronic applications as new EC and resistive switching materials.

The effects of alkyl and aryl ether structures in the main chain on the EC and resistive switching behaviour of triphenylamine unit have not yet been reported.

This paper aims to study previously prepared and fully characterized chitosan nanoparticles (CNPs) as a starting substrate and microwave initiation technique for grafting acrylic acid (AA). This was done to see the influence of both CNPs with respect to well-dispersed nanosized particles, large surface areas, biodegradability, biocompatibility and reactivity and microwave initiation technique with respect to reduction in organic solvents, toxic chemical initiator and exposer time on exploiting the graft yield % and enhancing water solubility and antibacterial properties.

For evaluating the best accurate standard metrological method for calculating the graft yield %, the grafting parameters were stated in terms of graft yield percent and measured gravimetrically (based on dry weight method) and titrimetrically (based on carboxyl content). Microwave power, AA and CNPs concentrations and reaction duration were shown to be the most important parameters influencing the grafting process.

The optimum reaction conditions were obtained when CNPs 1.5 g, AA 150 bows, microwave irradiation power 500 W and reaction duration 120 s were used. Various analytical methods were used to characterize CNPs and poly(AA)–CNPs graft copolymers. According to the findings, Fourier transform infrared spectroscopy examination determines the attachment of carboxyl groups to CNPs chains. The thermogravimetric analysis revealed that the copolymers were more thermally stable than CNPs counterparts. Furthermore, the resulting copolymers were shown to have greater water solubility biodegradability resistance and antibacterial properties than CNPs counterpart. Finally, a preliminary mechanism demonstrating all occasions that occur during the polymerization reaction has been proposed.

The advancement addressed here is undertaken using previously prepared and fully characterized CNPs as a green bio-nanocompatible polymer and microwave initiation technique as green and efficient tool with respect to reduction in organic solvents toxic chemical initiator and exposer time for grafting AA.