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Article
Publication date: 8 September 2021

Gemma Pascual, Josep García-Raurich, José M. Canal and Marta Riba-Moliner

This study aims to demonstrate that orange-derived and lemon-derived systems can be used in continuous processes as efficient adsorbents to the entrapment of some anionic…

Abstract

Purpose

This study aims to demonstrate that orange-derived and lemon-derived systems can be used in continuous processes as efficient adsorbents to the entrapment of some anionic and cationic dyes in the textile dyeing wastewater effluents.

Design/methodology/approach

Physically and chemically modified orange and lemon mesocarps are used as natural adsorbents for the cationic dyes Basic Blue 3, Basic Yellow 21, Basic Red 18 and Basic Green 4 and the anionic dyes Acid Blue 264, Acid Yellow 49 and Acid Red 337, all commonly used in the textile dyeing industry. Adsorption capacities of the orange-derived and lemon-derived adsorbents on the dyes are studied simulating a batch and continuous industrial processes.

Findings

Results demonstrate that treated orange mesocarp (orange-derived adsorbent) can adsorb up to 97% of cationic Basic Green 4 in 30 min, whereas the lemon mesocarp (lemon-derived adsorbent) can retain up to 88% within the same time. In the case of anionic, 91% Acid Blue 264 is adsorbed by the orange mesocarp in 15 min, whereas 92% is adsorbed by the lemon homologue within the same time.

Originality/value

As far as the authors know, physically and chemically modified orange and lemon mesocarps have not been used on the removal of cationic (Basic Blue 3, Basic Yellow 21, Basic Red 18 and Basic Green 4) and anioinic (Acid Blue 264, Acid Yellow 49 and Acid Red 337) dyes of textile dyeing wastewater industry. It is a costless and efficient treatment that supposes, on the one hand, an eco-friendly and feasible process for discolouration of wastewater and, on the other, a valorisation (upcycling) of orange and lemon peels, which are not currently used.

Details

Pigment & Resin Technology, vol. 50 no. 5
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 29 April 2014

Shuling Cui

Based on clarifying the structural difference between jade fibre and general polyester fibre, this paper aims to study the dyeing properties and dyeing adsorption…

Abstract

Purpose

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.

Design/methodology/approach

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.

Findings

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.

Originality/value

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.

Details

Pigment & Resin Technology, vol. 43 no. 3
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 26 June 2020

Haojia Su, Zhengchun Cai, Zhengwei lv, Yongkang Chen and Yongxin Ji

In this work, the authors used reversible addition-fragmentation transfer (RAFT) polymerization to develop a new cationic acrylate modified epoxy resin emulsion for…

Abstract

Purpose

In this work, the authors used reversible addition-fragmentation transfer (RAFT) polymerization to develop a new cationic acrylate modified epoxy resin emulsion for water-borne inkjet which have the advantages of both polyacrylate and epoxy resin. The emulsion was successfully used in the canvas coating for inkjet printing. This paper aims to contribute to the development of novel cationic emulsions for inkjet printing industry.

Design/methodology/approach

In this work, the epoxy acrylate was synthesized from RAFT agent and epoxy resin firstly. Cationic macromolecular emulsifier was prepared by RAFT polymerization, using 2,2’-Azobisisobutyronitrile as initiator, 2-(dimethylamino)ethyl methacrylate and styrene as monomer, which was directly used to prepare the emulsion. The influences of the amount of 2-(dimethylamino)ethyl methacrylate on particle size, zeta potential and water contact angle were studied. Finally, the cationic emulsion was used to print images by inkjet printing.

Findings

The emulsion has the smallest particle size, the highest potential and the highest water contact angle when the DM content is 13 Wt.%. The transmission electron microscopy analysis reveals the latex particles is core-shell sphere with the diameters in the range 120–200 nm. The emulsion was successfully used in the canvas coating for inkjet printing. This work will contribute to the development of novel cationic emulsions for inkjet printing industry.

Originality/value

The emulsion was successfully used in the canvas coating for inkjet printing. This work will contribute to the development of novel cationic emulsions for inkjet printing industry.

Details

Pigment & Resin Technology, vol. 49 no. 5
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 23 March 2020

Manuel Palencia, Mayra Mora and Tulio A. Lerma

Controlled release systems are an efficient alternative for the effective use of agricultural supplies. Among the most versatile controlled release systems are intelligent…

Abstract

Purpose

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).

Design/methodology/approach

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.

Findings

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.

Research limitations/implications

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

Practical implications

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.

Social implications

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

Originality/value

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.

Details

Smart and Sustainable Built Environment, vol. 10 no. 1
Type: Research Article
ISSN: 2046-6099

Keywords

Article
Publication date: 17 August 2010

Marian Sulek, Tomasz Wasilewski and Malgorzata Zieba

Modern cutting fluids often are real aqueous solutions of chemical compounds. That form of cutting fluid is simpler in preparation, as compared to emulsions and…

Abstract

Purpose

Modern cutting fluids often are real aqueous solutions of chemical compounds. That form of cutting fluid is simpler in preparation, as compared to emulsions and microemulsions. The water base is a good cooling medium of high‐ecological value. The purpose of this paper is to discover water‐soluble additives that could improve the lubricity of water.

Design/methodology/approach

Three cationic surfactants were chosen to be analyzed. Their tribological properties were verified using two testers: T0‐2 (four‐ball machine) and T‐11 (ball‐on‐disk). The results of the tests performed using friction couples made of steel (T0‐2, T‐11) and steel‐ceramics (T‐11) were satisfactory.

Findings

The friction coefficients and wear scar diameters are even a few times smaller, as compared to the ones measured in a water environment.

Originality/value

The paper demonstrates that the crucial role in improvement of the tribological properties is played by the surface activity of the additives (confirmed by the measurements of the surface tension and wetting angle). As the cationic surfactants are bactericidal and anti‐corrosive, they can be classified as multi‐purpose additives modifying water lubricity.

Details

Industrial Lubrication and Tribology, vol. 62 no. 5
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 22 March 2011

Kongliang Xie, Aiqin Hou and Lei Xu

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.

Abstract

Purpose

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.

Design/methodology/approach

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.

Findings

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.

Originality/value

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.

Details

Pigment & Resin Technology, vol. 40 no. 2
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 1 June 2002

G. Bereket and A. Yurt

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…

Abstract

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 Ecorr value, together with change in anodic and cathodic Tafel slopes (ba, bc), 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.

Details

Anti-Corrosion Methods and Materials, vol. 49 no. 3
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 1 February 2009

C.H. Kwong and S.P. Ng

Cationic dyes exhibit high exhaustion towards protein fibres, such as wool and silk, due to ionic interactions but they show little substantivity onto cellulosic and…

Abstract

Cationic dyes exhibit high exhaustion towards protein fibres, such as wool and silk, due to ionic interactions but they show little substantivity onto cellulosic and hemicellulosic fibres. In order to apply cationic dyes to mill scoured and bleached linen fibers, a new approach employing anionic agents containing a reactive monochloro-S- triazinyl group is synthesized and used to import a negative charge to the fibre surface.

Two cationic dyes show considerable substantivity towards anionic agent modified fabrics. Four different anionic agents are covalently bounded to the linen substrate to provide an electrostatic interaction with cationic dyes. The anionic agent treated fabrics are monitored for nitrogen content, and the reaction efficiency is determined as a K/S value of the dyed samples.

Different factors that affect the pretreatment and dyeing process are investigated, and an overall improvement in the effectiveness of the anionic agent on the dyeability using cationic dyes is achieved. The reaction efficiency for the four anionic agents follows the order: anionic agent III > I > II > IV > untreated fabric. The treated dyed fabrics also exhibit good fastness properties.

Details

Research Journal of Textile and Apparel, vol. 13 no. 1
Type: Research Article
ISSN: 1560-6074

Keywords

Article
Publication date: 4 July 2016

Wen Li, Zhongbin Bao, Lijun Chen and Dongshun Deng

At present, the conventional method of preparing cationic fluorinated acrylic latex is to emulsify copolymerised monomers with cationic surfactants. However, there has…

Abstract

Purpose

At present, the conventional method of preparing cationic fluorinated acrylic latex is to emulsify copolymerised monomers with cationic surfactants. However, there has been a wide concern about using Gemini surfactants to prepare cationic polymer latex to improve its properties. The purpose of this paper was to focus on the synthesis of novel self-crosslinked cationic fluorinated acrylic latex (SCFAL), during which the copolymerised monomers were initiated with a water soluble azo initiator and emulsified with mixed surfactants of Gemini emulsifier and alkyl polyglycoside (APG).

Design/methodology/approach

The novel SCFAL was prepared successfully by the semi-continuous seeded emulsion polymerisation of butyl acrylate, methyl methacrylate, hexafluorobutyl methacrylate (HFMA) and hydroxy propyl methacrylate (HPMA) in aqueous medium.

Findings

The conversion is the maximum and the coagulation percentage the minimum when the amounts of emulsifier and initiator are 8 and 0.6 per cent, respectively. The average particle size of the latex is significantly reduced with the increase of the amount of emulsifiers used. However, the average particle size of the latex is increased with the increase of the amount of HPMA. The particle size of the latex is of a unimodal distribution, which means that the particle size was reasonably uniform. Contact angle is increased with the increase of the amount of the HFMA.

Practical implications

The novel SCFAL can be widely used as significant components in the field of coatings, leather, textile, paper, adhesives and so on.

Originality/value

SCFAL, which was emulsified with novel mixed surfactants of Gemini surfactant and APG, has been prepared successfully. Influences of amount of initiator, emulsifier, HPMA and HFMA on emulsion polymerisation and/or properties of novel latex are investigated in detail.

Details

Pigment & Resin Technology, vol. 45 no. 4
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 1 June 1989

Bo Bredenberg

In recent years there has been a growing interest in cationic curing or polymerization. So far most of the work has been directed towards radiation curing, but there is a…

Abstract

In recent years there has been a growing interest in cationic curing or polymerization. So far most of the work has been directed towards radiation curing, but there is a coming interest in heat cured cationic systems as well.

Details

Pigment & Resin Technology, vol. 18 no. 6
Type: Research Article
ISSN: 0369-9420

1 – 10 of 599