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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.

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.

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.

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.

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.

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.

The purpose of this paper is to synthesize a polyacrylate-based dispersant with a determined target molecular weight for oily systems and to determine the optimal dispersant level and monomer ratio of the dispersant.

The dispersant was synthesized by conventional radical polymerization using methacrylic acid, butyl acrylate and dimethylamino ethyl methacrylate as the monomer. It was characterized by Fourier transform infrared spectroscopy, nuclear magnetic hydrogen spectroscopy, gel permeation chromatography and thermogravimetric analysis. The dispersant was used to disperse TiO₂, and the performance of the dispersant was evaluated by measuring the viscosity, particle size and dispersive force of the slurry.

The dispersant exhibited high thermal stability and was successfully anchored to the surface of the TiO₂ pigment. When used to disperse a TiO₂ slurry, it effectively made the TiO₂ slurry more fluid, indicating its strong viscosity-reducing properties. The viscosity, particle sizes and dispersion capabilities of the TiO₂ slurry were found to vary depending on the contents and monomer ratios of the dispersant.

P(MAA-BA-DM) dispersant increases the wettability of TiO₂ only in oily solvents but not in aqueous solvents.

P(MAA-BA-DM) dispersant makes it easier to disperse TiO₂ pigments in oily solvents, increasing the amount of pigment in the solvent and making the preparation of highly pigmented pastes easier.

A dispersant containing suitable carboxyl and tertiary amine groups was initially synthesized to disperse TiO₂ in an oily system. The findings are anticipated to be used in the formulation of pigment concentrates, industrial coatings and other solvent-based coatings.

This paper aims to study the physical and chemical characteristics of inkjet titanium dioxide inks for cotton fabric digital printing.

Different dispersing agents through the reaction of glycerol monooleate and toluene diisocyanate were prepared and then performed by using three different polyols (succinic anhydride-modified polyethylene glycol PEG 600, EO/PO Polyether Monoamine and p-chloro aniline Polyether Monoamine), to obtain three different dispersing agents for water-based titanium dioxide inkjet inks. The prepared dispersants were characterized using FTIR to monitor the reaction progress. Then the prepared dispersants were formulated in titanium dioxide inkjet inks formulation and characterized by particle size, dynamic surface tension, transmission electron microscopy, viscosity and zeta potential against commercial dispersants. Also, the study was extended to evaluate the printed polyester by using the prepared inks according to washing and crock fastness.

The obtained results showed that p-chloro aniline Polyether Monoamine (J) and succinic anhydride modified polyethylene glycol PEG 600 (H) dispersants provided optimum performance as compared to commercial standards especially, particle size distribution data while EO/PO Polyether Monoamine based on dispersant was against and then failed with the wettability and dispersion stability tests.

These ink formulations could be used for printing on cotton fabric by DTG technique of printing and can be used for other types of fabrics.

The newly prepared ink formulation for digital textile printing based on synthesized polyurethane prepolymers has the potential to be promising in this type of printing inks, to prevent clogging of nozzles on the printhead and to improve the print quality on the textile fiber.

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.

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.

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.

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).

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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

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.

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.

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.

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

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.

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.