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Article
Publication date: 4 September 2017

Zhongping Tang, Zhengwen Feng, Peng Jin, Xisheng Fu and Hua Chen

The purpose of this paper is to identify the feature of soot in diesel engine oil and provide a method to stably disperse these soots using effect additives which is…

Abstract

Purpose

The purpose of this paper is to identify the feature of soot in diesel engine oil and provide a method to stably disperse these soots using effect additives which is benefical for lubricants to pass related engine tests.

Design/methodology/approach

This paper designed experiments to investigate the dispersant type, treat level and different dispersant interactions which influence on lubricant soot-related viscosity increase. The research work developed an effective dispersant package which can well solve the soot-related viscosity increase, allowing pass Mack T-11 and Mack T-8 engine tests and demonstrated the helpfulness of using a quickly screening method developed by a steel piston diesel engine CA 6DL2-35.

Findings

The effect of dispersant treat level on the viscosity increase of the oil samples was negligible. Dispersant booster can effectively improve the soot handling ability of heavy-duty diesel engine oils (HDDEO), and the appropriate treat level of dispersant booster can help HDDEO pass Mack T-8 and Mack T-11 engine tests.

Practical implications

The test results are useful for formulators to select the appropriate dispersants or dispersant booster to develop the HDDEO packages which can meet the modern diesel engine lubrication requirements.

Originality/value

Most previous studies in this field were carried out on soot formation mechanism and soot-related wear rather than how to solve the soot-related viscosity increasing of HDDEO. This paper describes the soot dispersing requirements of different HDDEO specifications and developed an effective dispersant package which can well deal with Mack T-11 and Mack T-8E standard engine tests soot handling ability requirements.

Details

Industrial Lubrication and Tribology, vol. 69 no. 5
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 1 August 1998

John Clayton

Various types of ionic and non‐ionic dispersants have been classified by their ability to stabilise titanium dioxide pigment suspensions in water. It was found that some…

Abstract

Various types of ionic and non‐ionic dispersants have been classified by their ability to stabilise titanium dioxide pigment suspensions in water. It was found that some non‐ionic dispersants produced suspensions that exhibited full steric stabilisation as opposed to electrosteric stabilisation that occurs with ionic dispersants. A high level of steric stabilisation was found to relate to greater flocculation resistance in both the wet and dry phases, which can result in improved paint stability and higher opacity.

Details

Pigment & Resin Technology, vol. 27 no. 4
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 1 June 1972

M.A. Kessick, I.H. McEwan and H.W. Zacharewicz

Dispersant and surfactant additives, although used in minor amounts, exert a major influence in latex paints, controlling, for example, long‐term and freeze‐thaw stability…

Abstract

Dispersant and surfactant additives, although used in minor amounts, exert a major influence in latex paints, controlling, for example, long‐term and freeze‐thaw stability in the can, application properties, and the opacity, gloss, and scrub resistance of the dry film. In such complicated multiphase systems, exact knowledge of the role played by these dispersants and surfactants and their distribution is vital to optimum formulation. For instance, the amount of dispersant required to ensure pigment deaggregation during ‘grinding’, and to ensure stability of the resultant mill base, has been one of the principal concerns of paint formulators. Several techniques to determine this have been reported‐i.e., Daniels Flow Point measurements in resin or dispersant solutions, or Brookfield viscosity measurements at various dispersant levels after dispersion, and titration of pigment with dispersant solutions with a Brabender Plastigraph‐type sigma blade mixer.

Details

Pigment & Resin Technology, vol. 1 no. 6
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 1 April 1977

K.S. ANAND, O.N. ANAND and M.M. SINGH

MODERN heavy‐duty motor oils are almost invariably formulated with detergent‐dispersant type of additives. The types of additive normally employed for this purpose are…

Abstract

MODERN heavy‐duty motor oils are almost invariably formulated with detergent‐dispersant type of additives. The types of additive normally employed for this purpose are organo‐metallic detergent‐dispersants such as metal salts (barium/calcium) of alkyl phenols, petroleum and synthetic sulphonic acids, condensation products of olefins and P2S5, alkyl salicylic acids, etc., on the one hand, and the polymeric ashless types of dispersants such as polymethacrylic esters and N‐substituted long chain alkyl succinimides, on the other. Barium and calcium salts of the petroleum sulphonic acids, however, are by far the most widely used dispersant‐detergent additives. These additives are manufactured from the sodium salts or the sulphonic acids obtained as a by‐product during the sulphonation of mineral oils for the manufacture of white oils and transformer oils. The average molecular weight of the sodium salts is in the range 450—500.

Details

Industrial Lubrication and Tribology, vol. 29 no. 4
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 14 September 2015

Nehal S. Ahmed, Hamdy S. Abdel-Hameed, Ahmed F. El-Kafrawy and Amal M. Nassar

The aim of this paper is to solve the problem of carbonaceous deposits in automotive engines by preparing different ashless detergent/dispersant additives based on…

Abstract

Purpose

The aim of this paper is to solve the problem of carbonaceous deposits in automotive engines by preparing different ashless detergent/dispersant additives based on propylene oxide (PO) and different amines. Carbonaceous deposits in automotive engines are the major problems associated with oil aging. Efficient detergents and dispersants have been used to solve this problem, particularly in lubricating oils.

Design/methodology/approach

The structures of the prepared compounds were confirmed using Fourier transform infrared spectroscopy (FT-IR), proton nuclear magnetic resonance (1H-NMR) and gel permeation chromatography (GPC) for determination of molecular weight. This was followed by the evaluation of the prepared compounds such as detergent/dispersant and antioxidants additives for lubricating engine oil using several techniques such as variation of viscosity ratio, change in total acid number, optical density using infrared techniques, spot method, determination of sludge and determination the potential detergent dispersant efficiency (PDDE).

Findings

All the prepared compounds were found to be soluble in lubricating oil. The efficiency of the prepared compounds such as antioxidant and detergent/dispersant additives for lubricating oil was investigated. It was found that the additives have excellent power of dispersion, detergency and the most efficient additives such as antioxidant those prepared by using n,n-dimethyloctadecylamine (NDOA) and di-n-butyl dithio phosphoric acid.

Practical implications

The paper includes preparation of new compounds from the reaction of propoxylated amines and different organic acids and evaluates them as detergent/dispersant and antioxidants additives by using several techniques.

Originality/value

This paper fulfils an identified need to prepare new compounds from the reaction of propoxylated amines and different organic acids and evaluates them as additives by using different methods. All were found to have better efficiency as compared with commercial additives.

Details

Industrial Lubrication and Tribology, vol. 67 no. 6
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 9 November 2010

Peter Greenwood

The purpose of this paper is to investigate epoxysilane‐modified silica sols as surfactant‐free inorganic pigments dispersants and as co‐binders/reinforcing agents for…

Abstract

Purpose

The purpose of this paper is to investigate epoxysilane‐modified silica sols as surfactant‐free inorganic pigments dispersants and as co‐binders/reinforcing agents for silicate paints.

Design/methodology/approach

The performance of epoxysilane‐modified silica sols as dispersants for titania was studied using a polyacrylate‐based dispersant as reference. Furthermore, the effect of the addition of silica sols, with or without silane modification, to potassium silicate on binder properties was investigated.

Findings

Significant improvements were obtained in stability towards settling in water‐based titania pigments pastes and in light‐scattering efficiency (as much as 50 per cent) for the optimal size of the silica particle of 5 nm. The number of silane molecules per nm2 silica particle surface must exceed a critical value of at least 1 molecule of epoxysilane per nm2 particle surface. Additionally, improved stability towards gelling, water resistance and film‐forming properties of sol‐silicate binder mixes were achieved for epoxysilane‐modified silica sols.

Research limitations/implications

Only epoxysilane‐modified silica sols were studied in this report. Titania pigment was examined but other important pigments (e.g. iron oxides) remain to be studied. In addition, only sol‐silicate mixes were investigated and not fully formulated silicate paints.

Practical implications

A method that produces stable, high‐performing, surfactant‐free inorganic pigments pastes. Furthermore, stable, high‐ratio, sol‐silicate binders can be obtained with improved water resistance and film properties for use in silicate paints.

Originality/value

The present method provides an easy route to obtain stable surfactant‐free inorganic pigments pastes, as well as makes stable, high‐ratio, sol‐silicate mixes/paints.

Details

Pigment & Resin Technology, vol. 39 no. 6
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 4 November 2013

Yufei Xiu, Kezhong Wang, Chaoxia Wang, Kashif Javed, Shaohai Fu and Anli Tian

– The aim of this paper was to prepare a stable fluorescent disperse yellow paste by wet grinding process by adding naphthalene sulphonic derivative dispersing agent.

Abstract

Purpose

The aim of this paper was to prepare a stable fluorescent disperse yellow paste by wet grinding process by adding naphthalene sulphonic derivative dispersing agent.

Design/methodology/approach

The dispersants 2-naphthalenesulphonic acid (NNO), naphthalene-sulphonic acid (MF) and benzyl naphthalene sulphonate formaldehyde condensate (CNF) were used to disperse the yellow dye. The particle size of the paste was characterised by particle size analyser. The paste centrifugal stability, diffusion properties, morphology and thermal properties were also tested for assessing its stability which could be helpful to prepare inks with good stability.

Findings

The particle sizes of dye pastes with dispersing agent NNO, MF and CNF were 161.1, 150.0 and 136.0 nm, respectively, after grinding for 6 h. The dye paste grinded with dispersing agent CNF presented good centrifugal and thermal properties. TEM images demonstrated that the morphologies of dye pastes grinded with dispersing agent MF and CNF were homogeneous nearly spherical nanoparticle and rarely generated agglomeration and precipitation.

Originality/value

The paste used for aqueous inkjet ink exhibited excellent thermal stability.

Details

Pigment & Resin Technology, vol. 42 no. 6
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 19 October 2018

Christiana Agbo, Collins Acheampong, Liping Zhang, Min Li and Shai Shao Fu

This study aims to evaluate the use of polyoxyethylene lauryl ether (PLE) as a dispersant in the preparation of novel pigment dispersion with enhanced dispersion ability…

Abstract

Purpose

This study aims to evaluate the use of polyoxyethylene lauryl ether (PLE) as a dispersant in the preparation of novel pigment dispersion with enhanced dispersion ability, which can find application in the printing industry.

Design/methodology/approach

To obtain a good dispersion, PLE was used as a dispersant in pigments dispersion. The colloidal and rheological properties of the PLE-based dispersion, such as particle distribution, zeta potentials and apparent viscosity were evaluated.

Findings

The particle sizes of the pigment dispersions were within the range of 150 to 200 nm. The measurement of zeta potentials varied between −24 to −32 mV, revealing a strong surface charge interaction between pigments and PLE. Subsequently, its stability to high-speed centrifuge and freeze-thaw treatment was carefully investigated. To demonstrate the coverage of pigment particles by PLE, thermogravimetric analysis was carried out. Moreover, X-ray diffraction was used to disclose the combined impacts of PLE and ultrasonic power on the crystal structures of the pigments. Finally, the coloring performance and leveling properties of pigment dispersions on cotton substrates were evaluated by measuring their K/S values (color strength), rub and color fastness properties, which possessed good results.

Research limitations/implications

The dispersant used is incompatible with strong oxidizing agents and strong bases. More so, modification to improve its dispersion properties can be studied.

Practical implications

The use of PLE as a dispersant could be readily used in pigment dispersion processes and other suitable applications. PLE could also be used as a co-surfactant in synergy with other surfactants or dispersants in the dispersion process.

Originality/value

The use of PLE in pigment dispersion as well as investigating its coloring properties on cotton fabric is novel and can find various applications in the dying, printing and coating industry.

Details

Pigment & Resin Technology, vol. 48 no. 1
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 1 September 1998

C. Hinczewski, S. Corbel and T. Chartier

Ceramic three‐dimensional parts can be produced by a stereolithography (SL) process using a ceramic suspension containing alumina powder, UV curable monomer, diluent…

Abstract

Ceramic three‐dimensional parts can be produced by a stereolithography (SL) process using a ceramic suspension containing alumina powder, UV curable monomer, diluent, photoinitiator and dispersant. The monomer reacts to UV radiation (argon ionized laser) and is transformed into a solid polymer which is then removed by thermal treatment (debinding). Subsequent sintering of green parts leads to dense ceramic parts. The effect of each component on the rheology of the alumina suspensions has been studied first. Both the addition of dispersant and diluent and the increase in temperature allow a significant decrease of the viscosity of the suspensions. The highly loaded (more than 55 vol. per cent), homogeneous and stable suspensions have a shear thinning behaviour which is favourable for casting the layers. Adequate cured depth (above 200μm) and satisfactory transversal resolution have been obtained and these allow the production of ceramic parts, which demonstrates the feasibility of the process. Sintering at 1,580°C leads to dense ceramic parts with homogeneous microstructure. The process still needs to be optimized to improve even more the mechanical properties.

Details

Rapid Prototyping Journal, vol. 4 no. 3
Type: Research Article
ISSN: 1355-2546

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Article
Publication date: 1 May 1977

SMA 1440H, a member of ARCO Chemical Co's family of low molecular weight styrene and maleic anhydride copolymers has established a new level of performance in pigment…

Abstract

SMA 1440H, a member of ARCO Chemical Co's family of low molecular weight styrene and maleic anhydride copolymers has established a new level of performance in pigment dispersion technology. Coatings manufacturers have developed commercial formulations in which SMA 1440H has been shown to perform as an all inclusive one component dispersant in latex paint formulations; replacing as many as 4–5 other types of dispersants. Because of its anionically charged chemical structure and complementary design of hydrophilic‐hydrophobic properties, SMA 1440H can effectively disperse and stabilise many different types of pigments. SMA 1440H, a polyelectrolyte resin becomes water insoluble as the paint film cures and, therefore, contributes to film reinforcement. SMA 1440H is the ammoniacal solution of SMA 1440A.

Details

Pigment & Resin Technology, vol. 6 no. 5
Type: Research Article
ISSN: 0369-9420

1 – 10 of 453