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In this study, fabrication of polymer and cotton fabric exhibiting stimuli-responsive wetting and water vapor permeability features together with antibacterial activity was aimed.

Temperature and pH-responsive poly(N-isopropyl acrylamide-graft-chitosan) (PNIPAM-g-CS) copolymer were produced via the free radical addition polymerization method and fixed to the cotton fabric using butane tetracarboxylic acid (BTCA) cross-linker by double-bath impregnation method. The chemical structure of the graft copolymer was characterized by Fourier-transform infrared spectroscopy (FT-IR) spectroscopy and H-Nuclear magnetic resonance (1H NMR) analyses. Thermo-responsive behavior of the fabric was investigated by wetting time and water uptake tests, contact angle measurement and surface energy calculation. Additionally, antibacterial activity of the fabric treated with copolymer was studied against S. aureus bacterium.

PNIPAM-g-CS graft copolymer was synthesized successfully, which had lower critical solution temperature (LCST) value of 32 °C and exhibited thermo-responsive property. The treated fabrics exhibited hydrophilic character at temperatures below the LCST and hydrophobic character at temperatures above the LCST. It was found that polymer-coated fabric could have regulated the water vapor permeability by the change in its pore size and hydrophilicity depending on the temperature. Additionally, treated fabric displayed a pH-responsive water absorption behavior and strong antibacterial activity against S.aureus bacterium.

In the study, it has been shown that the cotton fabrics can be fabricated which have antibacterial activity and capable of pH and temperature responsive smart moisture/water management by application of copolymer. It is thought that the fabric structures developed in the study will be promising in the production of medical textile structures where antibacterial activity and thermophysiological comfort are important.

Wetting wood plastic composites (WPCs) prior to testing can be challenging because of the inherent water repellency of the plastic. The purpose of this paper is to explore the use of heating and wetting to accelerate moisture uptake on two WPCs.

Full size samples of the two WPCs were immersed in water at various temperatures or heated in an autoclave. Samples were removed periodically and dissected to determine the moisture profile by oven drying and weighing.

Moisture uptake is accelerated by heating, but the effect is mainly confined to the outer 5 mm of the samples. Moisture levels deeper in the samples are largely unaffected.

Moisture uptake can be enhanced by heating, but the inability to increase moisture levels deeper in the wood suggests that tests assessing the role of moisture on WPC properties should use thinner specimens to ensure that moisture is well distributed in the materials.

The results suggest the need for a re‐evaluation of test methodologies for WPCs where moisture uptake is an integral part of the procedures to more closely align the methods to the WPC/moisture behaviour.

This paper will help researchers develop better methods for assessing the role of moisture in WPC behaviour.

This paper aims to analyse the coating behaviour in corrosion environment as well as to evaluate the best percentage amount of copper oxide and copper needed for organic coating in order to prevent the corrosion degradation. Electrochemical impedance spectroscopy (EIS) studies have been conducted in order to evaluate the corrosion performance of polyester-epoxy-copper oxide and polyester-epoxy-copper coating systems.

The availability of this modem instruments is used to obtain impedance data as well as computer programs to interpret the results that made the technique popular. In addition, EIS is well suited to the study of polymer-coated metals.

The results showed that samples containing 25 weight per cent of copper oxide and copper (90P25CuO and 90P25Cu) obtained the excellent corrosion properties from the first day up to 30 days of NaCl immersion. The highest corrosion resistance values obtained by 90P25CuO and 90P25Cu on the 30th day were 7.107 × 108 O and 5.701 × 108 O, respectively, with lower double layer capacitance of 1.407 × 10⁻⁹ Farad and 3.935 × 10⁻⁹ Farad, respectively. Moreover, the water uptake gained by these two coating samples was the lowest at the end of immersion, which was 0.0084 for 90P25CuO and 0.1592 for 90P25Cu, showing that the sample has good corrosion performance.

This paper discussed on the highest corrosion resistance, double layer capacitance and the water uptake of the copper (Cu) and copper oxide (CuO) coating system obtained from the EIS measurements.

White pine wood was impregnated with a mixture of methyl methacrylate (MMA) and N‐methacryloyloxyphthalimide and by other three mixtures prepared by mixing MMA and N‐methacryloyloxytetrabromo‐phthalimide. Water uptake of treated wood was found to be 54 per cent after water‐soaking test of 168 h and maximum antiswell efficiency was found to be 48 per cent for treated wood samples with non‐brominated comonomer mixture.

Summary The present work aims to study the inhibition mechanism of barium metaborate pigments. Six grades of barium metaborate pigments were prepared in the Laboratory of Polymers and Pigments, National Research Centre of Cairo, Egypt. The methods of preparation modification and evaluation is the main subject of a recent article. The pigments were incorporated, with other ingredients, into formulations, and the electrode potential, electrical resistance, water uptake and weight loss measurements were taken. Formulations based on a commercial pigment supplied by an international company were prepared and used as blanks.

The effects of amount of conventional surfactant sodium dodecyl sulfate in the synthesis of carboxylated acrylic latices prepared by semicontinuous emulsion polymerization method were investigated. The properties considered were particle size and colloidal stability by addition of sodium chloride solution, on the latex system and water sorption, tensile strength at break and elongation, on latex films. It was found that the surfactant concentration had an important effect on the above mentioned properties. The particle size decreases with increasing surfactant concentration and the colloidal stability has a maximum value. The critical coagulation concentration value found in this work, seems to indicate an additional stabilisation of latex particles, due to a steric factor. The water uptake and the mechanical behaviour of latex films are affected considerably when SDS concentration rises. In conclusion, depending on the final use of latex, there is an optimal surfactant concentration for which the properties are appropriate.

The purpose of this paper is to investigate and present the properties of a new substrate material based on thermoplastic polymers (so‐called LuVo Board) for high‐frequency applications.

The thermal, mechanical and electrical properties of a new thermoplastic substrate are investigated and compared to conventional substrates for printed circuit board (PCB) applications.

The new LuVo Board exhibits similar properties to commercially available high‐performance substrates. The main advantage of the LuVo Board is a reduction of manufacturing costs in comparison to conventional substrates, as a highly automated manufacturing process can be employed. Moreover, the LuVo Board exhibits some further advantages: the material is inherently flame resistant and can be thermally shaped after the assembly process.

This paper presents an entirely new thermoplastic substrate, which can be employed in high‐frequency applications. In comparison to standard materials, a further advantage of the thermoplastic substrate is lower production costs.

The purpose of this study was to compare the physico-chemical properties and amino acid profile of three maize hybrid cultivars grown in Nigeria.

Two normal maize endosperm varieties, yellow SUWAN-ISR (YNM) and white ART/98/SW05-OB-WC (WNM), and one yellow QPM variety, TZE-POP-DT-STR-QPM (YQPM), were selected for the study. Physico-chemical properties, physical tests, proximate composition analysis, functional properties and characteristics and amino acid profile tests were carried out on the grains using standard methods.

Protein was significantly higher (p < 0.05) in YQPM (10.49 per cent) than in normal endosperm, YNM (8.83 per cent) and WNM (8.50 per cent). Amino acid profile of the grains revealed that total amino acid of YQPM (94.67 g/100 g of protein) and essential amino acid of YQPM (39.070) were the highest among the three, with highest significantly different value of tryptophan (0.388 g/100 g of protein) at p < 0.05. The cooking quality of YQPM was found to be better than the other two, with highest hydration capacity and increase in volume after cooking (90.8 ± 0.01 g/1000 grains and 147.53 ± 0.02 per cent).

YQPM will be highly beneficial in the tropics, where maize is grown as the major staple food to reduce hunger and malnutrition because of its amino acid balance and its better cooking quality.

The above Congress, being held at the Imperial College of Science and Technology, London, from April 10–15, has been described as likely to be the corrosion event of the decade. Size alone is no criterion, though over 80 papers are being presented, but the standing of many of the corrosionists associated with the Congress is, perhaps, the best indication of the truth of this statement. Summaries and abstracts of some of the papers appear in the following pages. More will be published in next month's issue.

Three types of polypropylene knitted fabrics in terry pile (uncut) structures with a similar knit design are developed by using fine denier filaments to make the inner layer for extreme cold weather clothing. The denier per filament is varied to assess its influence on thermo-physiological comfort properties, viz. thermal conductivity, thermal resistance and absorptivity, air permeability, water vapour permeability and wicking. The thermal properties are measured with an Alambeta instrument, and in-plane liquid flow through the fabrics is measured by using a gravimetric in-plane wicking tester. A statistical analysis is carried out at the 95% significance level for different experiments to establish the specific trend exhibited by the fabrics. It is observed that the water uptake increases, but water vapour permeability decreases with a decrease in filament denier. The thermal properties and air permeability values do not show any specific trends with filament denier. The porosity value is observed to be similar for all three developed fabrics.