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Potentiodynamic polarisation studies were carried out on the inhibition of low carbon steel in 0.1M hydrochloric acid solution over the temperature range 20‐60°C at different inhibitor concentrations by various quaternary ammonium salts and cationic surfactants. The inhibitors examined were tetraethyl ammonium chloride, tetrabutyl ammonium chloride, benzyltrimethyl ammonium chloride, benzyltriethyl ammonium chloride, benzyltributyl ammonium chloride, phenyltrimethyl ammonium chloride, alkylbenzyldimethyl ammonium chloride, tetradecyltrimethyl ammonium bromide and cetyltrimethyl ammonium bromide. Maximum inhibition efficiencies of cationic surfactants were observed around and above critical micelle concentration (cmc), while the inhibition efficiencies of the quaternary ammonium salts were found to increase with the increase in their concentrations. The degree of shift in E_corr value, together with change in anodic and cathodic Tafel slopes (b_a, b_c), revealed that cationic surfactants behave as an anodic inhibitor, while quaternary ammonium salts behave as mixed type inhibitors. Inhibition efficiencies of studied inhibitors seem to be closely related with the chain length of the alkyl group as well as the presence of benzene ring in quaternary ammonium compounds. Thermodynamic and kinetic parameters for dissolution and adsorption were also calculated.

The purpose of this paper is to investigate the inhibiting properties of six quaternary ammonium salts, three cationic surfactants and two non‐ionic surfactants in 2 M KOH. An attempt also was made to correlate some molecular parameters of these compounds with their corrosion inhibitor efficiency.

The inhibition efficiencies of quaternary ammonium salts, cationic surfactants and non‐ionic surfactants on the corrosion of zinc in 2 M KOH solution were investigated by potentiodynamic polarisation, electrochemical impedance spectroscopy and linear polarisation methods.

Inhibition efficiencies of quaternary ammonium salts were found to be due to physical absorption on the cathodic sides of zinc electrode and dependence of inhibition efficiencies on substituents were found. Physical adsorption of cationic surfactants on zinc electrode slowed down both anodic and cathodic reactions; thus they were found to be mixed type inhibitors. On the other hand, inhibition behaviour of non‐ionic surfactants was found to be due to adsorption on zinc via polar groups. It was found that non‐ionic surfactants behaved as mixed type inhibitors.

Clarifies the role of molecular structure and substituents on the inhibition efficiency of surfactants and quaternary ammonium compounds on the corrosion of zinc in alkaline media.

The inhibiting effects of 2,6‐ionen and 2,10‐ionen type polyvinylbenzyltrimethylammonium chloride, and latex, on low carbon steel in hydrochloric acid solution was investigated by potentiodynamic polarisation measurements and impedance measurement techniques over the temperature range of 20‐60°C at different inhibitor concentrations. It was found that the inhibition efficiencies increased with increasing inhibitor concentration. The degree of shift in E_corr values, together with the change in anodic and cathodic Tafel slopes (β_a, β_c), revealed that the studied inhibitors behaved as anodic inhibitors. Thermodynamic and kinetic parameters for dissolution and adsorption were also calculated.

The purpose of this research is to prepare a dispersion resin with good dispersity and a colour paste with good stability. At present, the colour paste is being prepared using the pigment dispersion resin which has the group quaternary ammonium. The dispersion resin prepared has good dispersity of pigment and extender. However, the stability of storage and construction of the colour paste is relatively poor, which has a negative influence on the application of cathodic electrodeposited (CED) coatings. However, the detailed investigation on the dispersion resin and the stable colour paste has not been reported.

Three steps are adopted to prepare the dispersion resin, that is blocking toluene diisocyanate (TDI), quaternary ammoniation of blocked TDI and ring opening of epoxy resin. The resultant dispersion is used to prepare the colour paste. The factors, which have an influence on the dispersity of the dispersion resin and stability of the colour paste, are optimised.

The typical recipes of preparing the dispersion resin and the resultant colour paste are obtained. The dispersity of the dispersion resin and stability of the colour paste are good based on the typical recipe. In addition, the film of the CED coating is smooth, dense and hard when the colour paste is used in the CED coating.

The dispersion resin can be used to prepare a colour paste, which can be used in the CED coatings. In addition, it also can be applied as a binder of coatings and adhesions.

The factors, which have an influence on the dispersity of the dispersion resin and stability of the colour paste, are studied in detail. The typical recipes of preparing the dispersion resin and the resultant colour paste are obtained. Based on the typical recipe, the dispersity of the dispersion resin and stability of the colour paste are good.

This paper aims to improve the adsorption capacity of sugarcane bagasse (SCB) as a low-cost, attractive and effective adsorbent for dye removal from wastewater.

SCB is a cellulosic material; it was chemically modified with compounds containing cationic groups. The adsorption efficiency of unmodified and modified SCB was investigated with anionic dyes by studying various factors that affect modified SCB and adsorption.

X-ray diffraction, FT-IR spectra and nitrogen content were used to confirm the effect of existence of quaternary ammonium groups on modified SCB. The morphological structure of the modified and unmodified SCB has been demonstrated using electronic scanning microscopy.

The modified SCB was chemically treated by Quat 188, which is commercially available in the solution of 3-chloro-2-hydroxypropyltrimethyl ammonium chloride.

Grafting cationic function groups on the surface of sugarcane by cationization treatment enhances its adsorption efficiency for anionic dyes.

The main value of this research was indicating a clear difference in the appearance of unmodified and modified SCB surfaces. Furthermore, it can be determined that the modified SCB absorbs more of the dyes.

The purpose of this paper is to develop the efficiency of styrene-acrylate (SA) emulsions for polymer cement waterproof coatings with improved bacteria resistance and mechanical properties.

For effective bacteria resistance and excellent mechanical properties, various concentrations of methacryloxyethylhexadecyl dimethylammonium bromide (MHDB) were synthesised and incorporated into SA emulsions. The properties of SA emulsions modified with MHDB were characterised and compared with those of unmodified ones according to the formulations of polymer cement waterproof coatings.

The SA emulsions modified with MHDB exhibited significant enhancement of bacteria resistance and mechanical properties over the unmodified ones. The positive quaternary nitrogen and long-chain alkyl groups of MHDB in SA emulsions could attract phospholipid head groups of bacterial and insert them into the cell wall, which results in biomass leak and bactericidal effect. Moreover, MHDB as a softened monomer was beneficial to the synthesis of SA copolymer with low glass-transition temperature (T_g), then the copolymer and cement would form a more compact film which was the main reason for the enhancement of mechanical properties.

The modifier MHDB was synthesised from diethylaminoethyl methacrylate (DEAM) and 1-bromohexadecane. Besides, the congeners of MHDB could be synthesised from DEAM and 1-bromododecane, 1-tetradecyl dromide, 1-octadecyl bromide, etc. In addition, the efficiency of other modifications into SA emulsions for antibacterial polymer cement waterproof coatings could be studied as well.

The method provided a practical solution for the improvement of water-based antibacterial acrylate polymer cement waterproof coatings.

The method for enhancing bacteria resistance and mechanical properties of the waterproof coating was novel and valuable.

Controlled release systems are an efficient alternative for the effective use of agricultural supplies. Among the most versatile controlled release systems are intelligent or stimulus-sensitive polymeric materials, since these materials are multipurpose and adaptable alternatives that offer great adaptability for agricultural applications. The objective of this work was to develop stimulus-sensitive polyurethanes (PUs) based on cationic aminoglycosides (CAG) to be used as an active phase for the manufacture of systems for the controlled release of phytohormones such as naphthalene acetic acid (NAA).

The synthesis of stimulus-sensitive PUs was carried out by a polycondensation reaction using CAGs and methylene diphenyl isocyanate (MDI) as precursors. The NAA retention and release experiments were performed at different pH values and ionic forces to include the acidity and salinity of agricultural soils.

The results demonstrate that PUs can be obtained from CAG and MDI using the one-step method. The retention of NAA increased as the CAG content increased in the polymer structure, while it is seen that the effect of pH is weak compared to the effect of ionic strength. On the other hand, the release of NAA from cationic PUs can be accomplished by small changes in ionic strength that are mainly affected by the composition of the PU and the pH. The results suggest that, for developed systems, retention and release of NAA is affected by other interaction mechanisms that could probably be related to p-aromatic interactions.

Findings are limited to controlled conditions and the expanding of results to extensive crops should be analyzed in next research studies.

The practical implications of this study are improving of control for the dosage of phytohormones in stake propagation crops, greenhouse crops, optimization of reseeding operations, among others.

The social implication of this study is reduction of pollution by addition of excess of NAA, in consequence, production costs are decreased.

Originality and value of this research is the use of PUs based on CAG, and in consequence, the possibility to build novel environment-friendly systems for phytohormone dosage.

The purpose of this paper is to investigate the effect of self‐emulsifying polysiloxanes containing multi‐cationic groups as resin on fastness properties of dyed cellulose fabrics.

Cellulose fabrics were dyed with three reactive dyes. Then, the self‐emulsifying polysiloxanes containing multi‐cationic groups as resin were applied to the dyed cellulose fabrics. The fastness properties were investigated.

The results show that the wet rubbing fastness, washing fastness and perspiration fastness of three dyed samples treated with novel self‐emulsifying polysiloxanes are higher than those of the dyed samples without the polymer treatment. The complexes of cellulose with the polysiloxanes having multi‐cationic groups are formed. With the increase of the quantity of cationic groups in the polymer macromolecules, the wet rubbing and washing fastness further increase. The self‐emulsifying polysiloxanes can affect the colour yields (K/S) of the dyed fabrics.

The self‐emulsifying polysiloxanes containing multi‐cationic groups are novel functional materials. They are easily self‐emulsifying in water, without the need of disperse agents, and form a transparent macromolecule colloid solution. Self‐emulsifying polysiloxanes as resins can change material properties to improve their wet fastness and gloss. They have potential application as resins in the coloration industry. This paper is an original research report and has not been published previously.

This study aims to deal with the dyeing of nylon-/cotton-blended fabric in one bath using direct and acid dyes.

The cellulose in cotton/nylon-blended fabric was chemically modified using 3-chloro-2-hydroxypropyl tri-methyl ammonium chloride (CHPTAC) as cationizing agent to impart positive charge on the cellulose. The modified and unmodified blended fabrics were dyed in a single bath with direct and acid dyes under various concentrations of 0.5, 1, 2, 4 and 6 per cent on the weight of fabric by exhaust method. The dyeing of modified and unmodified fabrics was characterized through the properties such as K/S and colorfastness to washing, rubbing and light.

The modified fabric exhibited higher color yield, comparable rubbing fastness and good washing fastness.

The dye uptake was maximum in a single-bath dyeing process of nylon-/cotton-blended fabrics without electrolyte addition, which minimizes the impact of dyes on environment.

The purpose of this paper is to improve the dyeability of flax fibre by modification via urea treatment and to explore the mechanism of such improvement.

The modification to the flax fibre was carried out with different concentrations of urea solution, then the optimum condition for the dyeability improvement was investigated by the measurement of the dyeing colour depth. The chemical properties of the raw and the treated flax fibres were characterised using a variety of techniques including Fourier transform‐infrared spectroscopy analysis and X‐ray photoelectron spectroscopy analysis.

It was found that the dyeability of flax fibre had been significantly improved via urea treatment. The mechanism of the improvement of the dyeability of the flax fibre was found to be due to the amino groups (NH₂) introduced to the flax fibres during urea treatment, which increased the activity of the reaction between the dye and the fibre compared to hydroxyl groups of raw flax fibre.

The treatment method developed provided a practical and effective solution to poor dyeability of flax fibre.

The method could be adapted for use in industrial scale flax dyeing with satisfactory levels of exhaustion and fixation.