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This paper aims to examine the effect of wax, calcites and clay on the stability of petroleum emulsions. It proposes a proxy model that takes into cognizance the presence of solids other than asphaltene and resin. This study aims to investigate the combined effects of these solids on the stability of emulsions and show their relevance or otherwise in the creation of petroleum emulsions.

This paper used synthetic emulsions based on a response surface methodology using different weight concentrations of wax, calcites and clay. A Box–Behnken design model was adopted and the effects of the different variables on emulsion stability were analyzed. The conventional visual observation (batch testing) was augmented with a more robust technique of studying emulsion stability (Turbiscan) based on light backscattering or transmission. Analysis of variance and other statistics were used to analyze the results.

The paper makes an available proxy model that can predict the stability of petroleum emulsions in the presence of wax, calcites and clays. The findings suggest that in the presence of significant amount of wax (0.3 Wt.%), the presence of relatively lower concentration of clay (0.1 Wt.%) produces very stable petroleum emulsions. The results show that the most stable emulsion is obtained when significant amount of wax exists in the continuous phase and that a concentration of calcites more than wax (in a ratio of at least 2:1) produces an emulsion that separates very fast, indicating low stability.

Due to the variations in the amount of asphaltene and resins in crude oils, the proxy model cannot generally predict the stability of every emulsion that forms in the presence of these solids. To have a more general model, it should include asphaltene/resin. This can be tested further.

This paper provides useful information to the oil industry, especially where formation of severely stable emulsion is a problem. It also establishes the relationship that exists between solids in emulsion stabilization.

This paper satisfies a demand on the effects of other surface-active materials in addition to asphaltene/resin in stabilizing petroleum emulsions.

Epoxy resin emulsions are used in water‐based coatings for surface protection of concrete and metal. An unfortunate drawback for most emulsions is their poor freeze‐thaw stability. Epoxy emulsions are indeed unstable below 0°C, ‐5°C or ‐10°C, depending on the type of resin. In this study, other factors capable of influencing the freeze‐thaw behaviour were investigated: e.g. solids content, amount and type of emulsifiers, solvents, protective colloids. Discusses methods for testing the quality of thawed emulsions as well as the physics involved in their destabilization. Freeze‐thaw performance can be improved by different means but mostly not without sacrificing resistance properties of the coating. Therefore, avoiding temperatures below 0°C is still the best advice.

The purpose of this paper is to prepare waterborne UV-curable pigment pastes for cotton fabric printing.

O/W (oligomer-in-water) emulsions of polyurethane acrylate (PUA) oligomer in sodium dodecyl benzene sulphonate (SDBS) aqueous solution were prepared by ultrasonic emulsification method.

The present work studies various factors affecting the stability and droplet size of the O/W emulsion stabilised by SDBS. The optimal emulsifier concentration was 2.5 per cent, under which condition the stability of the emulsion increased as the emulsifier content increased, with a subsequent decrease in the droplet size of the emulsion, while above which emulsion agglomeration occurred. Increasing the power and duration of ultrasonic dispersion resulted in increased emulsion stability and decreased droplet size, while increases in the oligomer content reduced the emulsion stability. Darocure 1173 mixed with PUA and then emulsified in the SDBS aqueous solution guaranteed uniform dispersion of the photoinitiator, resulting in faster curing speed.

This paper presents a new method for making waterborne externally emulsified oligomers for UV curing, and finds that it is easy to convert the existing oligomers into waterborne equivalents by this method. Cotton fabrics printed with the oligomer emulsion based pastes were found to have good colour strength and crockfastness.

The effects of ultrasonication on the epoxy resin and its emulsion were investigated to find out the changes in the M_η and molecular structure of epoxy, as well as its room temperature storage stability, centrifugal stability, particle size and its distribution and particle morphology more importantly with the influence of different ultrasonic irradiation time, power and temperature.

The emulsion was prepared using an emulsifier with epoxy resin and by using phase inversion after subjecting to ultrasound irradiation with a power of 200 W at 50°C for 60 min. The changes in the epoxy resin and its emulsion induced by ultrasound were characterized by Ubbelohde viscometer, FT-IR, ¹³C-NMR, high-speed desktop centrifuge, laser particle size analyzer and transmission electron microscope.

The molecular weight of the epoxy resin was initially decreased and then stabilized by the increasing of ultrasonic irradiation time. The mole rate of the epoxy groups in epoxy molecular were decreased by about 14 per cent, resulting from ultrasonic irradiation. The particle size of the emulsion was decreased, while the particle size distribution became uniform in a certain time. The narrow distribution, stable and uniform of waterborne epoxy resin emulsion with more than 60 days room temperature storage period, 80 per cent of the supernatant volume, about 220 nm average particle size was gained with a power of 200 W at 50°C for 60 min.

To overcome the problems commonly encountered with an epoxy emulsion, for example, short storage period and wider particle size, which limit its practical application, the effects of ultrasonic irradiation on the epoxy resin and its emulsion, were investigated. As the stability of emulsion was improved with the introduction of ultrasonic irradiation, the application of epoxy emulsion was improved.

The room temperature storage stability and centrifugal stability of the emulsion were decreased by the mechanical method, and thus, the benefit of an in-depth understanding of the influence of ultrasonic treatment on epoxy resin and its emulsion could further promote the development of water-based coatings.

No one particular fluid has cooling and lubrication properties suitable for every metalworking application. The purpose of this paper is first, to investigate the effect of anionic and nonionic mixed emulsifier system in stabilization of cutting fluid formulations and second, to study the interaction synergism of the fulfill additives of metalworking fluids to achieve low scar diameters, high stability, anti rusting and corrosion properties.

A lot of set mixtures in this work were formulated to get the demand needed for soluble oil metalworking fluids. It was based on a blend of emulsifier package (anionic‐non ionic), and in order to reach acceptable manufacturing conditions, coupling agent, stabilizer, biocide, base oil and anti‐rust additives were added to the formulation. Different percentages of these components were incorporated to optimize the stability of the emulsifier system. Standard tests were carried out to evaluate the performance of oil‐in‐water (O/W) emulsions as lubricating and cooling fluids in machining operations. The evaluation was drawn in five factors; oil stability, emulsion stability, pH, anti‐rust (corrosion inhibition), biological activity and extreme pressure performance tests.

All tests achieved excellent results according to the ASTM. From the obtained results, the formula (named EPRI 950) exhibited a good performance compared with the commercial cutting fluid.

This work investigates the effect of anionic and nonionic mixed emulsifier system in stabilization of cutting fluid formulations; and the interaction synergism of the fulfill additives of metalworking fluids to achieve low scar diameters, high stability, anti‐rusting and corrosion properties.

Oil‐in‐water (O/W) emulsion has been used in industrial rolling mills for many decades, but its lubrication mechanism is still not adequately understood. There is a need to understand the role of chemical ingredients and emulsifier in lubrication and tribological characteristics of rolling oil. With this purpose, the authors selected three commercially available O/W emulsions of different generations and of known industrial performance. The aim is to understand the lubrication mechanism of these rolling oils and to correlate the laboratory findings with that of industrial rolling mills.

The lubrication mechanism has been studied with the help of an ultra thin film interferometry EHD test rig, an advanced experimental rolling mill and a Coulter LS 230 instrument. Film thickness, rolling parameters and droplet size were measured. The coefficient of friction was computed with the help of the measured values of rolling parameters. Emulsion stability and saponification value (SAP) of the selected emulsions were also determined. The results of film thickness, rolling parameters and droplet size have been presented. The lubrication mechanism of the emulsions has been explained on the basis of film thickness, droplet size, emulsion stability, SAP value and coefficient of friction.

Results of the present study reveal that chemistry of O/W emulsions plays an important role in their film forming and tribological behavior. Rolling emulsions of relatively low stability, higher droplet size and high SAP value are found to provide better lubrication and lower coefficient of friction. The results of the present study correlate well with the actual industrial experience except those obtained on EHD test rig.

Coulter LS 230 instrument was available with M/s LUBRIZOL CORP., USA. Only limited study on droplet size was carried. Although the study carried out has given good information but it would have been more practical if the emulsion samples taken from the experimental mill stand would have been studied for droplet size.

From understanding point of view of lubrication mechanism of O/W emulsion, it will be useful for oil technologists, tribologists and rolling mill users.

The study is original in nature and gives information on lubrication mechanism of O/W emulsions in steel cold rolling of steel strips.

This study aims to investigate the influence of soy protein isolate hydrolysates (SPIH) obtained using 4 h hydrolysis under 200 MPa on proximate composition, cooking loss, textural properties, color, water distribution, microstructure, thiobarbituric acid reactive substance (TBARS) value and carbonyl and sulfhydryl contents of emulsion sausages.

Sausages with SPIHs at four concentrations (0, 1.0, 2.0 and 3.0%) were prepared, and the sausage with 0.01% butylated hydroxyanisole (BHA) was used as a positive control. Some sausages were selected for the analyses of quality characteristics and microcosmic properties. Other sausages were stored under 4 °C for 0, 7, 14, 21 and 28 days to investigate the oxidative stability.

The addition of SPIHs at various levels (0–3.0%) or 0.01% BHA did not affect the proximate composition (protein, fat and ash) of emulsion sausages. The addition of 2.0% SPIH decreased cooking loss and increased moisture content, hardness, springiness, chewiness, resilience and L* value, compared to the sausages without SPIH and with 0.01% BHA (p < 0.05). Furthermore, low-field nuclear magnetic resonance results suggested that sausages with 2.0% SPIH had the shortest T2 relaxation time. In addition, 2.0% SPIH and 0.01% BHA could inhibit the oxidation of emulsion sausages when compared with the sample without SPIH (p < 0.05). Moreover, there were no differences between sausages with 2.0% SPIH and 0.01% BHA (p > 0.05).

These findings confirmed that the 2.0% SPIH obtained under 200 MPa can be used as a natural additive to improve quality properties and antioxidant potential of emulsion sausages during storage.

Some of the properties of paints based on alkyd emulsion are discussed and they are divided into four categories. Colloidal stability of water based paints is predominantly governed by osmotic and electrostatic repulsion of both the binder and the pigment particles. The rheological behaviour of paints based on binder dispersions should be optimised by using thickeners with the proper mix of hydrophilic and hydrophobic polymeric segments. Stability of drying properties of alkyd emulsion paints upon storage can be strongly improved by preventing the use of ketoximes as anti‐skinning agents and by selecting the proper driers. Properties of the dried paints depend strongly on the process of film formation. The protective and aesthetical quality of films based on binder dispersions is governed by the key parameters of the resin that is within the droplets; viscosity, miscibility and the ability of the binder to undergo crosslinking. To obtain the total package of desired properties of water based paints it is necessary that all of the paint components are adjusted to each other. This can only be done if the companies that develop and market the raw materials work closely together. The use of fundamental knowledge in such co‐makerships results in better and faster developments.

Fluorine materials have received the keen attention of many researchers because of their water repellency and low surface free energy. The purpose of this paper is to prepare self-crosslinking fluorocarbon polyacrylate latexes containing different fluorocarbon chain lengths by semi-continuous seeded emulsion polymerization technology.

Methyl methacrylate (MMA), butyl acrylate (BA), hydroxypropyl methacrylate (HPMA) and fluorine-containing monomers were used as main monomers. The fluorine-containing monomers included hexafluorobutyl methacrylate (HFMA), dodecafluoroheptyl methacrylate (DFMA) and trifluorooctyl methacrylate (TFMA). Potassium persulfate (KPS) was used as thermal decomposition initiator, non-ionic surfactant alkyl alcohol polyoxyethylene (25) ether (DNS-2500) and anionic surfactant sodium dodecylbenzene sulfonate (SDBS) as mixed emulsifier.

Through optimizing the reaction conditions, the uniform and stable latex is gained. The polymer of structure was characterized by Fourier transform infrared spectroscopy (FTIR). Thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and contact angle (CA) were tested on latex films. The particle size and distribution range of emulsion were tested with nano particle size analyzer. After comprehensively comparing the latexes and films prepared by HFMA, DFMA and TFMA, the performance of DFMA monomer modified is better.

The self-crosslinking acrylic emulsion is prepared via semi-continuous seeded emulsion polymerization, which methyl methacrylate (MMA), butyl acrylate (BA), hydroxypropyl methacrylate (HPMA) and fluorine-containing monomers were used as main monomers. The fluorine-containing monomers were composed of hexafluorobutyl methacrylate (HFMA), dodecafluoroheptyl methacrylate (DFMA) and trifluorooctyl methacrylate (TFMA). Potassium persulfate (KPS) was used as thermal decomposition initiator, non-ionic surfactant alkyl alcohol polyoxyethylene (25) ether (DNS-2500) and anionic surfactant sodium dodecylbenzene sulfonate (SDBS) as mixed emulsifier. There are two main innovations. One is that the self-crosslinking acrylic emulsion is prepared successfully. The other is that the effects of monomers containing different fluorocarbon chain lengths on polyacrylate, such as monomer conversion rate, coagulation rate, mechanical stability, chemical stability, emulsion particle size and storage stability, are studied in detail.

Fluorine materials have received the keen attention of many researchers because of their water repellency and low surface free energy. The purpose of this paper is to prepare fluorine-containing soap-free acrylic emulsion, which sodium allyoxypropyl hydroxypropyl sulfonate (COPS-1) and anionic emulsifier sodium a-alkenyl sulfonate (a-AOS) were combined as polymerizable emulsifier, and undecylenic acid (UA) and dodecafluoroheptyl methacrylate(DFMA) were introduced as functional monomer.

The fluorinated polyacrylate emulsion was successfully prepared by semi-continuous seed emulsion polymerization, wherein the main monomers were methyl methacrylate (MMA) and butyl methacrylate (BA), and the initiator was potassium persulfate (KPS). Sodium alloxypropyl sulfonate (COPS-1) and an anionic emulsifier sodium a-alkenyl sulfonate (a-AOS) were compounded as a polymerizable emulsifier. Besides, undecylenic acid (UA) and dodecafluoroheptyl methacrylate (DFMA) were introduced as the functional monomers.

The optimum recipe of preparing the modified latex is as follows: the amount of emulsifier was 4%, the ratio of emulsifier (COPS-1: AOS) was 3: 1, and the content of initiator was 0.6%. In this case, the conversion rate of acrylic polymer emulsion was high and the polymerization stability was good. When the amount of monomer UA was 2% and the amount of DFMA was 4%, the overall performance of the emulsion was the best.

The fluorine-containing soap-free acrylic emulsion is prepared via semi-continuous seeded emulsion polymerisation, which sodium allyoxypropyl hydroxypropyl sulfonate (COPS-1) and anionic emulsifier sodium a-alkenyl sulfonate (a-AOS) were combined as polymerizable emulsifier, and undecylenic acid (UA) and dodecafluoroheptyl methacrylate (DFMA) were introduced as functional monomer. There are two main innovations. One is that the fluorine-containing soap-free acrylic emulsion is prepared successfully. The other is that the undecylenic acid is introduced as functional monomer.