Emerald | Pigment & Resin Technology | Table of Contents http://www.emeraldinsight.com/0369-9420.htm Table of contents from the most recently published issue of Pigment & Resin Technology Journal en-gb Tue, 29 Apr 2014 00:00:00 +0100 2013 Emerald Group Publishing Limited editorial@emeraldinsight.com support@emeraldinsight.com 60 Emerald | Pigment & Resin Technology | Table of Contents http://www.emeraldinsight.com/common_assets/img/covers_journal/prtcover.gif http://www.emeraldinsight.com/0369-9420.htm 120 157 A new single step synthesis of copper phthalocyanine green using microwave irradiation effects in functionalisation of C-H bonds in aromatic rings http://www.emeraldinsight.com/journals.htm?issn=0369-9420&volume=43&issue=3&articleid=17109181&show=abstract http://www.emeraldinsight.com/10.1108/PRT-04-2013-0029 <strong>Abstract</strong><br /><br /><B>Purpose</B> – The paper introduces a new method for single step synthesis of copper phthalocyanine green pigment using microwave irradiation to activate C-H bonds on the aromatic rings that are possible by creation of chlorine radicals. The aims of this study are to investigate the possibility of high-efficiency product reaction, removing acidic wastewater, time optimization, and maximizing number of chlorine on aromatic rings. <B>Design/methodology/approach</B> – The paper presents a new synthesis technique, which does not have the problems of the conventional methods. Microwave irradiation is used as a chemical reaction initiator by creation of chlorine radicals in saturated aqueous solution of sodium chloride and C-H bond activation on aromatic rings. The approach yields to a high quality of product, uniform particle size distribution, high efficiency and an environmental friendly procedure. <B>Findings</B> – The paper introduces the use of suitable materials and water solvents in chemical reactions under microwave radiation at low temperatures. This shows that the microwave irradiation activates C-H bonds on aromatic rings and creates chlorine radicals at the same time, which results in relatively fast reaction of synthesis copper phthalocyanine green. <B>Research limitations/implications</B> – The ammonium molybdate catalyst, which is used in this method, should be weighed carefully. The effects of transition metals on chemical reactions in the presence of microwave irradiation can also be chlorinated other unsaturated bonds. <B>Practical implications</B> – The method develops a simple and practical solution to improve the synthesis of phthalocyanine green pigment. <B>Originality/value</B> – The synthesis method of copper phthalocyanine green pigment is novel. CuPhcCl<DN>16</DN> has numerous applications in industrial. Article literatinetwork@emeraldinsight.com (Behnam Seyyedi, Mohammad Edrisi, Maryam Seyyedi, Gholamreza Mahdavinia) Tue, 29 Apr 2014 00:00:00 +0100 Kinetic and diffusion studies of a dye extracted from <IT>Sesbania aculeata</IT> plant http://www.emeraldinsight.com/journals.htm?issn=0369-9420&volume=43&issue=3&articleid=17109182&show=abstract http://www.emeraldinsight.com/10.1108/PRT-06-2012-0041 <strong>Abstract</strong><br /><br /><B>Purpose</B> – The purpose of this paper is to evaluate the efficacy and kinetics along with diffusion properties of a new source of natural dye obtained from leaves and fine stems of the <IT>Sesbania aculeata</IT> plant, using metallic mordants for cotton dyeing. <B>Design/methodology/approach</B> – The approach followed in this work is to conduct experiments with the application of the natural dye obtained from <IT>Sesbania aculeata</IT> plant and to study the kinetics, dye uptake and the diffusion properties of this dye. <B>Findings</B> – <IT>Sesbania aculeata</IT> with simultaneous mordanting with different metal mordants imparted shades which varied from cream to light brown to dark brown in case of aqueous extract. The different mordants used not only changed the hue colour and K/S values but also L* and brightness index values. The results of fastness properties of the dyes were found to vary from fair to good. The percentage dye exhaustion values varied with different mordants. The dye uptake value increased with time and reached its saturation limit after 4 hours of dyeing. In the absence of mordants, the diffusion coefficient values increased with increase in the temperature. In the presence of mordants, the diffusion process appears to slow down, which could be attributed to the binding effects of mordants. <B>Research limitations/implications</B> – The extraction and dyeing process of <IT>Sesbania aculeata</IT> plant is less tedious and time consuming compared to the other sources of natural dyes. <B>Practical implications</B> – <IT>Sesbania aculeata</IT> is relatively easier to grow and does not require much tending operations. Thus, it promises to be an affordable source of natural dye. If this dye is commercialised, it will help to generate sustainable employment and income for the farmers in rural and sub-urban areas. This could be both for dyeing and for non-food crop farming. <B>Originality/value</B> – An advantageous feature of this plant, in contrast to the other natural dyes based on vegetable and fruit sources, is that its usage in making the natural dye does not result in any wastage of an otherwise highly commercial product. The current experimental study on a new source of natural dye would be a significant contribution to the existing database of knowledge regarding the kinetics and diffusion properties of natural dyes. There are several reported studies in the literature pertaining to the application of natural colourants and evaluation of their dyeing properties on various fibers. However, relatively fewer studies exist on the kinetic and exhaustion aspects. Thus, the current study would help to develop a set of predictable settings for application of natural dyes on various textiles. Article literatinetwork@emeraldinsight.com (C. Swami, S. Saini, V.B. Gupta) Tue, 29 Apr 2014 00:00:00 +0100 Inhibition of acid corrosion of mild steel by aqueous nettle extracts http://www.emeraldinsight.com/journals.htm?issn=0369-9420&volume=43&issue=3&articleid=17109183&show=abstract http://www.emeraldinsight.com/10.1108/PRT-11-2012-0078 <strong>Abstract</strong><br /><br /><B>Purpose</B> – The aim of this research was to investigate the use of aqueous extracts of nettle plant (NE) as a green corrosion inhibitor of mild steel in hydrochloric acid solution. <B>Design/methodology/approach</B> – The inhibition efficiency was investigated by weight loss measurements, potentiodynamic polarizations, electrochemical impedance spectroscopy, SEM observations and EDX analysis. <B>Findings</B> – The inhibition efficiency increased with an increase in concentration of NE up to a critical concentration of 1.5×10<UP>-3</UP>?g?·?cm<UP>-3</UP> where the highest inhibition efficiency of 97 percent was obtained. The adsorption of the inhibitor was spontaneous (reflected by the negative value of ?G<DN>ads</DN><UP>0</UP>), supported the mechanism of physical adsorption and obeyed to the Langmuir adsorption isotherm. The inhibition action of the extracts was independent on the storage time; it could be conserved without any specific conditions of time and temperature. <B>Research limitations/implications</B> – The anticorrosion effect can be better understood when the active compound in the extracts is identified and what is the inhibition efficiency of one component in the presence of another in the mixture (synergetic or antagonist effects). <B>Practical implications</B> – Nettle is a healthy plant, without particular toxicity that can find possible applications as environmentally friendly inhibitor of mild steel used as materials in food industry. <B>Originality/value</B> – Aqueous nettle extracts were studied for the first time as corrosion inhibitor and its anticorrosion effect was proven by standard methods. Article literatinetwork@emeraldinsight.com (Aida Zaabar, Razika Aitout, Laid Makhloufi, Kamel Belhamel, Boualem Saidani) Tue, 29 Apr 2014 00:00:00 +0100 Structure and dyeing properties of jade fibre http://www.emeraldinsight.com/journals.htm?issn=0369-9420&volume=43&issue=3&articleid=17109184&show=abstract http://www.emeraldinsight.com/10.1108/PRT-08-2013-0071 <strong>Abstract</strong><br /><br /><B>Purpose</B> – Based on clarifying the structural difference between jade fibre and general polyester fibre, this paper aims to study the dyeing properties and dyeing adsorption mechanism of jade fibre with disperse dye and cationic dye. <B>Design/methodology/approach</B> – The chemical structure and microstructure of jade fibre were briefly explained comparing with ordinary polyester fibre. The dyeing rate curve and dyeing adsorption isotherm of disperse dyes and cationic dyes on jade fibre were, respectively, studied. The dyeing uptake, dyeing absorption mechanism, and the main dyeing process parameters were proposed. <B>Findings</B> – Jade fibre can be dyed with cationic dye and disperse dye. The suitable exhaust dyeing process is 110°C and 40 minutes for disperse dye, 100°C and 60 minutes for cationic dye. The dyeing uptake on jade fibre with both disperse dyes or cationic dyes is much higher than that on general polyester fibre and acrylic fibre, and the dyeing adsorption mechanism belongs to the combination of Langmuir and Nernst adsorption for disperse dyes and Langmuir adsorption for cationic dyes. Comparing with ordinary polyester fibre, jade fibre has the advantage of low temperature dyeing and reduced effluent, as is significant to energy-saving and emission reduction. <B>Originality/value</B> – Jade fibre is a new type of modified polyester fibre with the function of health protection and energy conservation. There are little technical data in the literature at present about the dyeing property of jade fibre. Article literatinetwork@emeraldinsight.com (Shuling Cui) Tue, 29 Apr 2014 00:00:00 +0100 Study on manufacture method of poplar laminated composite floor by compression densification and gluing technology http://www.emeraldinsight.com/journals.htm?issn=0369-9420&volume=43&issue=3&articleid=17109185&show=abstract http://www.emeraldinsight.com/10.1108/PRT-02-2013-0016 <strong>Abstract</strong><br /><br /><B>Purpose</B> – This paper developed a new method of making floor from poplar using glued technology and densification technology. This paper aimed to use fast-grown poplar wood to produce floor to expand material supply range of floor in order to solve problem of material supply shortage for floor industry. <B>Design/methodology/approach</B> – Densification technology and gluing technology were used to obtain high-density surface materials of floor under high pressure, meanwhile in order to reduce loss of poplar wood caused by compressing, high-density surface materials floor and substrate are glued and pressed under low pressure. <B>Findings</B> – The method of compressing poplar wood under high pressure can improve poplar's physical and mechanical properties. Adopting densification technology and gluing technology can produce the poplar laminated composite floor which meets the requirements of Chinese standard GB/T 18103. <B>Research limitations/implications</B> – This method of producing floor by compression densification technology would cause wood loss from reduction in thickness because poplar was pressed under high pressure. <B>Practical implications</B> – This method of making floor from poplar wood concerned in this study allows the floor making industry to eliminate its dependence on precious wood resource, expand supply range of floor material, and then solve problem of wood supply shortage of floor industry. <B>Originality/value</B> – This study may help solve the difficult problem that poplar cannot directly be used to produce floor because of its softness, low density and low strength. Through densification technology, great improvement in strength and hardness of poplar had been made. Article literatinetwork@emeraldinsight.com (R.X. Cheng) Tue, 29 Apr 2014 00:00:00 +0100 Hydroxypropyl methylcellulose as a polymeric corrosion inhibitor for aluminium http://www.emeraldinsight.com/journals.htm?issn=0369-9420&volume=43&issue=3&articleid=17109186&show=abstract http://www.emeraldinsight.com/10.1108/PRT-05-2013-0037 <strong>Abstract</strong><br /><br /><B>Purpose</B> – The paper aims to investigate the effectiveness of hydroxypropyl methylcellulose (HPMC) as corrosion inhibitor for aluminium in 0.5?M H<DN>2</DN>SO<DN>4</DN> solution. <B>Design/methodology/approach</B> – This study was carried out using weight loss and electrochemical techniques. Inhibition efficiency was determined by comparing the corrosion rates in the absence and presence of inhibitor system. Quantum chemical computations were performed using density functional theory to assess the parameters responsible for the inhibition process and also to analyse the local reactivity of the molecule. <B>Findings</B> – HPMC inhibited aluminium corrosion in the acidic environment. The inhibition efficiency was found to depend on concentration of the inhibitor. Impedance results reveal that HPMC is adsorbed on the corroding metal surface. Polarization results show that the dissolution reaction is due to destabilization of the passive oxide film on the Al surface. Adsorption of the inhibitor is approximated by Freundlich adsorption isotherm and the calculated standard free energy of adsorption indicates weak physical interaction between the inhibitor molecules and aluminium surface. This can be attributed to preferential interaction of the active sites with the passive oxide layer. The calculated quantum chemical parameters show good correlation with the inhibition efficiency. <B>Practical implications</B> – HPMC could find possible application as a polymeric thickener and additive to improve corrosion resistance and barrier properties of anticorrosion paints. <B>Originality/value</B> – This paper provides novel information on the inhibitive characteristics of HPMC under the stated conditions. The inhibitor systems provide an effective means for suppressing aluminium corrosion even in highly aggressive acidic environments. Article literatinetwork@emeraldinsight.com (Innocent Okechi Arukalam, Innocent Chimezie Madufor, Okoro Ogbobe, Emeka E. Oguzie) Tue, 29 Apr 2014 00:00:00 +0100 Proper use of rice straw black liquor: lignin/silica derivatives as efficient green antioxidants for SBR rubber http://www.emeraldinsight.com/journals.htm?issn=0369-9420&volume=43&issue=3&articleid=17109187&show=abstract http://www.emeraldinsight.com/10.1108/PRT-01-2013-0001 <strong>Abstract</strong><br /><br /><B>Purpose</B> – The purpose of this paper is to study the efficiency of lignin/silica and calcium lignate/calcium silicate as natural antioxidants in styrene-butadiene rubber (SBR) vulcanizates. <B>Design/methodology/approach</B> – It has been found that thermal aging data of the aged sample revealed that SBR vulcanizate undergoes crosslink reactions that lead to embrittlement and ultimately failure. Incorporation of lignin/silica or calcium lignate/calcium silicate, however, resulted in significant improvement of the degradation profile of the vulcanizates at 90±1°C. Loss of tensile strength and flexibility during aging of the SBR compounds with 8?phr lignin/silica or calcium lignate/calcium silicate was mild relative to unfilled polymer, indicating a restricted degradation due to the presence of the investigated compounds. The results obtained revealed that the investigated compounds are good antioxidant, and the evaluation was confirmed by physico-mechanical properties of the vulcanizates, FT-IR spectroscopy, transmission (TEM) and scanning (SEM) electron microscope. <B>Findings</B> – It was noticed that SBR vulcanizates having 8?phr of lignin/silica or calcium lignate/calcium silicate exhibited the best mechanical properties in comparison with other concentrations (1, 2, 4, 6 and 10?phr). Also, results revealed that the lignin/silica derivatives are efficient antioxidants in SBR vulcanizates compared to vulcanizates containing conventional antioxidants used in rubber industry, namely polymerized 2,2,4-trimethyl-1, 2-dihydroquinoline (TMQ), and N-isopropyl-N'-phenyl-P-phenylenediamine (IPPD). <B>Research limitations/implications</B> – All these results indicated that lignin/silica and calcium lignate/calcium silicate in SBR had good heat resistance and aging resistance, calcium lignate/calcium silicate has an application limitation as not all vulcanizates need to use CaCO<DN>3</DN>/calcium salts. <B>Practical implications</B> – Lignin is usually seen as a waste product of pulp and paper industry and is often used as fuel for the energy balance of the pulping process. It is simple isolation along with silica from rice straw and using it as an antioxidant added further practical utility for this waste. <B>Originality/value</B> – The importance of lignin/silica derivatives is arisen from their biodegradability and their ease availability from rice straw black liquor. Article literatinetwork@emeraldinsight.com (Khlood S. Abdel Zaher, R.H. Swellem, Galal A.M. Nawwar, Fathy M. Abdelrazek, Salwa H. El-Sabbagh) Tue, 29 Apr 2014 00:00:00 +0100