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To discuss synthesis and evaluation of organo‐metallic chalcones as second‐order nonlinear optical (SONLO) materials.

The new chalcones have been synthesised via Knovoenagel reactions of ferrocen carboxaldehyde with two active methylene compounds.

The ferrocenyl chalcones prepared have shown bathochromic shift and thermal stability in polymeric film. On heating the dye films up to 80°C the extent of degradation reached up to 12 per cent and very small amount of degradation was observed at 43 and 60°C.

The paper shows that these compounds have UV‐Vis bathochromic shift, enabling them to be used as SONLO materials in the blue domain as well as dyes.

To identify the causes to the variation of shade of coloured acrylic sheets from one batch to another and to propose solution to alleviate such a phenomenon.

A number of analytical techniques, including spectrophotometric measurement, evaluation of dispersion stability, pigment particle size analysis, scanning electron microscopy and transmission electron microscopy, were employed to assess the degree of colour shade variation, the degree of dispersion and nature of the particles within the acrylic sheet formulations and the acrylic sheet products.

It was found that the variation of shade of the coloured acrylic sheets from one batch to another was mainly caused by the lack of dispersion stability of the pigment particles concerned over time.

The investigation found solutions to the variation of shade of the coloured acrylic sheets from one batch to another.

Colour and colour consistency are a key attribute of the coloured acrylic sheets. Although not frequently encountered, such imperfections were undesirable. The investigation identified the causes to such imperfections and found a way to eliminate such imperfections.

To discuss synthesis and evaluation of organo‐metallic dyes as second‐order nonlinear optical (SONLO) material.

New dyes have been synthesised via Knovoenagel reactions of ferrocene carboxyaldehyde and two active methylene compounds.

The ferrocenyl dyes prepared have shown bathochromic shift and thermal stability.

These compounds have UV‐Vis bathochromic shift, enabling them to be used as SONLO materials as well as dyes.

The paper provides further information on the thermal studies of these types of molecules.

The purpose of this paper is to synthesise a disperse dye based on benzisothiazole and to characterise its crystal morphology, dispersing stability, to study the relationship between the chemical structure and the dyeing property of the dye.

The disperse dye based on benzisothiazole, 3-(3-methyl-4-N-ethyl-N-benzyl-phenyldiazenyl)-5-nitro-2,1-benzisothiazoles, was synthesized. The disperse dye based on benzisothiazole, 3-(3-methyl-4-N-ethyl-N-benzyl-phenyldiazenyl)-5-nitro-2,1-benzisothiazoles, was synthesised. The chemical structure of the dye obtained was characterised by infrared spectrum Fourier transform infrared spectroscopy and nuclear magnetic resonance (1HNMR), and the crystal morphology was observed by Field Emission Scanning Electron Microscopy. Sodium salt of polycondensated naphthalenesulphonic acid (dispersing agent sodium salt of polycondensated naphthalenesulphonic acid [MF]) and a sulphonated amino polyether (anionic surfactant B600) were employed to grind and disperse the dye crystals. The dispersion property of the dye particles was characterised. Dyeing property of the dispersion system was also studied.

The dye formed spherical crystals that were made up of a large number of acicular crystals similar to spherical chrysanthemum. The crystals had warping crystal centres inside the spheres. The particle sizes of the dispersion with the mixture of B600 and MF had an uniform distribution and were smaller than that of the dispersion with only single dispersing agent MF. Dyeing with the dispersion system had an excellent reproducibility under alkalinic condition.

An alkalinic dyeing method for poly(ethylene terephthalate) (PET) with disperse dyes as a cleaner wet process had been developed. Such a process combined pretreatment and dyeing process using the alkali-stable disperse dyes and reduced the consumption of water and energy and improved production efficiency.

The crystal morphology, dispersion and dyeing properties of the synthesised disperse dye for dyeing PET fabric under alkalinic condition were discussed. This disperse dye has an important potential application in alkalinic dyeing method.

The purpose of this paper is to investigate in detail the effects of acid treatment on multi‐walled carbon nanotubes (MWNTs), which could find a variety of applications in coatings and composites.

A number of analytical techniques, including Fourier transform infrared spectroscopy (FT‐IR), X‐ray photoelectron spectroscopy (XPS), Raman spectroscopy (Raman), and scanning electron microscopy (SEM), were employed to assess the effects of acid treatment on MWNTs.

It was found that desirable modifications to MWNTs occurred after acid treatment. Thus, carboxylic acid groups were introducing on to the surface of MWNTs. It was also found that both chemical and physical properties of MWNTs could be modified/altered.

The investigation established a method to modify MWNTs via acid treatment and the effects of such a treatment on MWNTs in detail. The modified MWNTs can be used for various applications and further modifications. The acid treated and the further modified MWNTs can be dispersed into polymers to prepare polymer/MWNTs composite materials and composite surface coatings. Some properties of the resulting composites were improved by the dispersed MWNTs, giving excellent mechanical, electrical, thermal and magnetic properties.

The finding on the effects of acid treatment on MWNTs, supported by detailed FT‐IR, XPS, Raman and SEM data, would be of interest to the field. The modification technique provided a route to further modification of carbon nanotubes. The acid treated and the further modified MWNTs are useful for preparation of polymer/MWNTs composite materials and composites surface coatings with improved mechanical, electrical, thermal and magnetic properties.

The purpose of this paper is to investigate the effects of carbon nanotubes (CNTs) on the mechanical, thermal and colour properties of solvent-containing two-component polyurethane (PU) coating.

Fourier transform infrared spectroscopy and observation of dispersion stability were used to assess the effects of acid treatment on CNTs. The CNTs and PU composite coating was synthesised by in situ polymerisation and bending polymerisation, and the mechanical, thermal and colour appearance properties of coating were characterised.

It was found that desirable modifications to CNTs occurred after acid treatment; thus, mainly carboxylic acid groups were introduced onto the surface of CNTs. And the acid-treated CNTs could improve the mechanical and thermal properties of PU coating, and the properties of composite coating was improved more successfully by in situ polymerisation than by blending polymerisation.

The investigation established a method to synthesise CNTs and PU composite coating. The mechanical and thermal properties of PU coating could be improved by the inclusion of CNTs.

This study established a method to synthesise CNTs and PU composite coating by in situ polymerisation and blending polymerisation; the effects of CNTs on modifying mechanical, thermal and colour properties of PU coating were investigated and compared in detail.

The purpose of this paper is to investigate the effects of multi‐walled carbon nanotubes (MWNTs) on the mechanical, thermal and electrical conductivity properties of polyurethane (PU) by in situ polymerisation of MWNTs and PU.

A number of analytical techniques, including Fourier transform infrared spectroscopy and X‐ray photoelectron spectroscopy, were employed to assess the effects of acid treatment on MWNTs. The mechanical and thermal properties of PU, MWNTs and PU composites were characterised using a tensile tester machine and dynamic mechanical analysis. The electoral conductivity properties of the materials were characterised by ohmmeter.

It was found that desirable modifications to MWNTs occurred after acid treatment, thus mainly carboxylic acid groups were introduced onto the surface of MWNTs. And the acid‐treated MWNTs could improve the mechanical, thermal and electrical conductivity properties of PU by in situ polymerisation of MWNTs and PU successfully.

The investigation established a method to synthesise MWNTs and PU composites by in situ polymerisation. The mechanical, thermal and electrical conductivity properties of PU could be improved by the inclusion of MWNTs.

The paper establishes a method to synthesise MWNTs and PU composites by in situ polymerisation; and the effects of MWNTs on modifying mechanical, thermal and electrical conductivity properties of PU by in situ polymerisation are investigated in detail.

The purpose of this study to investigate the synthesis of new Cr(III), Fe(III), Ni(II) and Cu(II) Schiff base complexes by a simple technique (microwave technique). The evaluation of the prepared complexes as pigments as corrosion resistant was also explored.

The Schiff base complexes were prepared by using microwave method (green chemistry), and then, the physico-chemical requirements according to standards for the synthesised pigments were investigate.

The prepared complexes exhibit good physical, mechanical and corrosion properties as pigments in paint formulations.

The simple technique used for synthesis of metal complex pigments will significantly increase the cost saving for the manufacturing of such pigments category. Also, the used technique is considered a green method (eco-friendly), as there no organic solvent was used.

The evaluation of the prepared complex pigments as corrosion resistants was also studied.

It is a simple technique, green synthesis (no solvent used) is involved and high yield is obtained.