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Article
Publication date: 6 July 2015

N.P. Badgujar, Y.E. Bhoge, T.D. Deshpande, B.A. Bhanvase, P.R. Gogate, S.H. Sonawane and R.D. Kulkarni

– The present work aims to deal with ultrasound-assisted organic pigment (phthalocyanine blue and green) dispersion and its comparison with the conventional approach.

Abstract

Purpose

The present work aims to deal with ultrasound-assisted organic pigment (phthalocyanine blue and green) dispersion and its comparison with the conventional approach.

Design/methodology/approach

Ultrasound is expected to give beneficial results based on the strong shear forces generated by cavitational effects. The dispersion quality for preparation using an ultrasound-based method has been compared with dispersion obtained using high-speed dispersion mill. Effects of different operating parameters such as probe diameter and use of surfactants on the physical properties of dispersion and the colour strength have been investigated. Calculations for the energy requirement for two approaches have also been presented.

Findings

The use of sodium dodecyl sulphate and Tween 80 surfactants shows better performance in terms of the colour properties of dispersion prepared in water and organic solvent, respectively. Ultrasound gives better dispersion quality as compared to the conventional approach.

Originality/value

The present work presents a new approach of ultrasound-assisted dispersion of phthalocyanine blue and green pigments. Understanding into the effect of surfactants and type of solvent also presents new important design-related information.

Details

Pigment & Resin Technology, vol. 44 no. 4
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 1 April 1975

J. Hortensius

It is well known that water based coatings offer several advantages over solvent based coatings, such as: less air pollution, saving of energy, saving of raw materials and…

Abstract

It is well known that water based coatings offer several advantages over solvent based coatings, such as: less air pollution, saving of energy, saving of raw materials and noncombustibility, at least in liquid form and during application.

Details

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

Article
Publication date: 6 July 2015

Lijun Chen, Zhongbin Bao, Zhengrong Fu and Wen Li

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…

Abstract

Purpose

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.

Design/methodology/approach

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.

Findings

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.

Practical implications

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.

Originality/value

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.

Details

Pigment & Resin Technology, vol. 44 no. 4
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 5 March 2018

Aarti P. More and Shashank T. Mhaske

The study aims to synthesise polyurethane dispersion from polyesteramide polyol. The polyesteramide polyol is a novel polyol for the synthesis of polyurethane dispersion.

Abstract

Purpose

The study aims to synthesise polyurethane dispersion from polyesteramide polyol. The polyesteramide polyol is a novel polyol for the synthesis of polyurethane dispersion.

Design/methodology/approach

Polyesteramide polyol has been synthesised from phthalic anhydride and fatty amide of mustard oil. Aminolysis of mustard oil had been carried out with diethanolamine. The novel polyurethane dispersion had been synthesised using a polyesteramide polyol as a precursor. Isophorone diisocyanate was used as an isocyanate component and polyurethane dispersion (PUDs) had been synthesised by an anionic method where DMPA was introduced to introduce –COOH groups as via grafting to the resin backbone. Triethylamine was used for neutralisation and, hence, for further dispersion in water. Hydroxyl ethyl methacrylate was used for the synthesis to introduce unsaturation in the backbone of PUDs. The coating was made by an UV curing process. The coating was characterised for mechanical properties, chemical properties, thermal properties as well as stain resistance.

Findings

The polyurethane dispersion formed through it has ester and amide linkage present in it. The acetone process is used for its synthesis. The nuclear magnetic resonance spectroscopy confirms the successful formation of polyesteramide polyol and PUDs. Even though long aliphatic chains present in polyol which may impart hydrophobicity the synthesis PUDs well dispersed in water. It is observed as the coating made from it have hardness and scratch resistance properties. The coating also exhibits good stain resistance properties.

Practical implications

The method is an easy one to synthesise polyurethane dispersion from polyesteramide polyol, which is based on ester and amide linkage.

Originality/value

To the best of the authors’ knowledge, this is the first report on synthesised polyurethane dispersion from polyesteramide polyol. The polyesteramide resin already proves its excellence and upcoming technology in the coating industry. Here, they are incorporated into the synthesis of polyurethane dispersion.

Details

Pigment & Resin Technology, vol. 47 no. 2
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 1 September 2006

A. Ferrari, F. Stefani and D.T. Beruto

To study the rheological behavior of aqueous dispersions of collagen gelled media and to bring it into relation with the gel stiffness and microstructure.

Abstract

Purpose

To study the rheological behavior of aqueous dispersions of collagen gelled media and to bring it into relation with the gel stiffness and microstructure.

Design/methodology/approach

Collagen gelled media were prepared at different concentrations and their stiffness was measured with dynamic elastic modulus (DEM) technique. The gelled media were reduced into dispersions of micelles and gel liquid phase and the apparent viscosity of these systems was investigated as a function of the gap thickness, the shear rate and the collagen concentration. The gap thickness was varied between 20 and 200 μm. The microstructure of the broken gelled media was finally explored with optical microscopy.

Findings

DEM analysis has given values of the collagen gel stiffness ranging between 3 × 10−4 and 3.3 × 10−3 MPa. It has been shown that apparent viscosity grows with the increase of the gap thickness from 2 to 5 Pa s at constant collagen concentration and applied shear rate (4 percent, 100 s−1). A rise in the collagen concentration has produced an increase in the apparent viscosity of gelled media dispersions. Nevertheless, the phenomenological law does not obey previously proposed equations but follows a sigmoid modal. Shear‐thinning phenomenon has been observed when the shear rate is varied between 10 and 2,000 s−1.

Research limitations/implications

The gel breaking process, which may cause changes in the microstructure of the micelles and hence in the rheological behavior of the dispersions, should be characterized measuring the forces acting on the samples during the rupture.

Originality/value

The paper provides useful information on the rheological behavior of aqueous dispersions of collagen gelled media.

Details

Industrial Lubrication and Tribology, vol. 58 no. 5
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 17 May 2022

Dongjun Lv, Xiaolei Zhang, Guocheng Gao, Jing Tang, Zilong Zhang, Yihui Liu, Ran Wang and LeiFang Liu

The purpose of this study was the preparation of a poly(styrene-co-maleic anhydride)-g-polyetheramine (SMA-g-PEA) hyperdispersant that reduces the viscosity of the system…

Abstract

Purpose

The purpose of this study was the preparation of a poly(styrene-co-maleic anhydride)-g-polyetheramine (SMA-g-PEA) hyperdispersant that reduces the viscosity of the system and improves the colouring intensities of pigments.

Design/methodology/approach

PEA of specific quality was dissolved in propylene glycol methyl ether. SMA was then added according to the required mass ratio. The solution was refluxed for 10 h under a stream of protective N2. The prepared hyperdispersant was then characterised by Fourier-transform infrared, UV–visible and 1H NMR spectroscopies, gel-permeation chromatography and thermogravimetry.

Findings

PEA was successfully grafted onto the SMA polymer and the synthesised product was found to be thermally stable. The copolymer with a 6:1 mass ratio is the best dispersant and was used to disperse carbon black, phthalocyanine blue and permanent violet in water-based systems, which helps to improve the application performance of each pigment by reducing the viscosity of the system and improving the colouring intensity of the pigment. The water dispersion is stable and does not exhibit an increase in viscosity after seven days of oven aging at 50°C.

Originality/value

SMA-g-PEA water-based hyperdispersants were successfully synthesised. The prepared hyperdispersants help to improve the application performance of each studied pigment by reducing the viscosity of the system and improving the colouring intensity of the pigment.

Article
Publication date: 4 July 2018

Gangqiang Zhang, Xiangqiong Zeng, Tianhui Ren and Emile van der Heide

The purpose of this paper is to investigate the tribological performance of graphene oxide (GO) sheets as water-based lubricant additive when ultra-high molecular weight…

Abstract

Purpose

The purpose of this paper is to investigate the tribological performance of graphene oxide (GO) sheets as water-based lubricant additive when ultra-high molecular weight polyethylene (UHMWPE) plates slid against 316L stainless steel ball using a reciprocating tribometre.

Design/methodology/approach

The factors influencing the tribological performance were considered, including the viscosity of the GO dispersion, normal load, sliding velocity and the roughness of UHMWPE. The surface microstructure and properties of UHMWPE were studied by means of scanning electron microscopy, laser confocal microscopy, Raman spectroscopy and contact angle measurements.

Findings

The results revealed that the GO dispersion reduced friction and sliding-wear. The surface images of the wear UHMWPE plates indicated that GO sheets were prone to adsorption on the surface and form a thin physical tribofilms at the substrate.

Originality/value

Based on the experimental findings for the evolution of the microstructure morphology and the development of subsurface cracks, less debris and cracking can be observed in the UHMWPE plates lubricated by GO dispersion.

Details

Industrial Lubrication and Tribology, vol. 70 no. 6
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 1 October 2002

Javier I. Amalvy

Polyurethane (PU) anionomer having 2‐ethoxymethacrylate terminal groups was prepared in a methyl methacrylate/n‐butyl acrylate mixture as a reactive diluent, following a…

Abstract

Polyurethane (PU) anionomer having 2‐ethoxymethacrylate terminal groups was prepared in a methyl methacrylate/n‐butyl acrylate mixture as a reactive diluent, following a prepolymer mixing process. This prepolymer‐acrylic monomer mixture was chain extended in a water/surfactant solution using different dispersion speeds. Stability tests of PU‐acrylic monomer dispersions before polymerization were performed at different temperatures by following the particle size evolution. After the dispersion process the kinetics of batch emulsion polymerization at 70°C using different concentrations of initiator was investigated. Data are compared with published results of batch emulsion copolymerization of methyl methacrylate/n‐butyl acrylate. The effect of triethylamine, used in the prepolymer synthesis, on the emulsion polymerization of acrylic monomers was also studied. The kinetic results indicate that during emulsion polymerization of PU acrylic mixture, some coagulation takes place, mainly due to changes in ionic strength of the medium, before stable latex particles are formed. The presence of the PU prepolymer seems not to affect the kinetics of batch copolymerization of methyl methacrylate/n‐butyl acrylate monomers.

Details

Pigment & Resin Technology, vol. 31 no. 5
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 1 October 1974

Matthew R. Yunaska and Andrew Mercurio

A review of water‐based thermosetting resins for industrial finishes includes the fundamental parameters of acrylic polymers and a comparison of emulsion, colloid and…

Abstract

A review of water‐based thermosetting resins for industrial finishes includes the fundamental parameters of acrylic polymers and a comparison of emulsion, colloid and solution properties.

Details

Pigment & Resin Technology, vol. 3 no. 10
Type: Research Article
ISSN: 0369-9420

Article
Publication date: 26 November 2021

Agnieszka Dudkiewicz, William Hayes and Bukola Onarinde

The purpose of this pilot-scale study was to compare the quality of traditionally manufactured butters from local, small British producers with the quality of butters that…

Abstract

Purpose

The purpose of this pilot-scale study was to compare the quality of traditionally manufactured butters from local, small British producers with the quality of butters that are produced industrially.

Design/methodology/approach

Butter samples were obtained after supervised site inspections of three traditional-butter manufacturers and one large-scale butter producer. The samples were subject to initial microbiological, chemical and sensory testing, followed by a refrigerated shelf-life study over 24 weeks.

Findings

Traditional butters matched or exceeded the sensory quality of industrial butters, but spoilage microorganisms tended to grow faster on traditional butters. This seemed to be related to poorer water droplet dispersion in the manufacture of some of the traditionally made butters. Visible mould appeared on two of the traditional butters after eight weeks, but this occurred well after the nominal “best before” date.

Originality/value

Prolonged lockdowns due to the current coronavirus disease (COVID-19) pandemic pose a threat to the food supply chain, and food produced by local manufacturers may become increasingly important. However, are foods produced by local small-scale manufacturers of a quality comparable to that produced using large-scale production facilities? To the best of the authors' knowledge, there is no comparative study of the quality and shelf-life of traditionally-produced and industrially-produced butters. The current work presents such a comparison together with an outline of how the process of traditional butter-making differs from commercial production in Britain.

Details

British Food Journal, vol. 124 no. 10
Type: Research Article
ISSN: 0007-070X

Keywords

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