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So‐called emulsifiers do many things. Although the addition of an emulsifier to some mixtures does emulsify them, the emulsification of other mixtures may require other ingredients as well. Some existing emulsions may actually be broken by the same emulsifier; others may be broken and converted to a new emulsion; and some materials may be changed in firmness, viscosity, wettability or other properties even when no emulsion is involved. To make matters even more complicated, the effect of a given emulsifier in a given system may vary dramatically with temperature. For example, the most familiar of emulsifiers, egg yolk, causes most of the difference seen between a pastry dough and a cake batter or between pastry and cake: at mixing temperature it causes the difference between a plastic solid and a pourable liquid, whereas at baking temperature it causes the difference between a rigid, friable solid and an elastic solid. Emulsifiers are used in a very wide range of industrial processes, from oil‐drilling to paint‐making and printing. However their use in the manufacture of food and beverages clearly requires the most stringent standards of identity. Under current UK legislation, food emulsifiers are regulated by the same statutory instrument as the so‐called stabilisers. The difficult problem of definition is approached on the basis of function :—

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.

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.

The purpose of this paper is to prepare stabile emulsions with 0–15% of colloidal silica and high monomer/water ratio and to investigate the influence of silica addition and surface modification on the polyacrylate properties.

Improving the properties of the composite can be achieved by optimizing the compatibility between the phases of the composite system with improving the interactions at the matrix/filler interface. Therefore, the silica surface was modified with nonionic emulsifier octylphenol ethoxylate, cationic initiator 2,2'-azobis-(amidinopropane dihydrochloride) and 3-methacryloxypropyltrimethoxysilane and polyacrylate/silica nanocomposites were prepared via in situ emulsion polymerization. Particle size distribution, rheological properties of the emulsions and morphology, thermal properties and mechanical properties of the film prepared from the emulsions were investigated.

Polyacrylate/silica systems with unmodified silica, silica modified with nonionic emulsifier and cationic initiator have micrometer, while pure PA matrix and systems with silica modified with silane have nanometer particle sizes. Addition and surface modification of the filler increased emulsion viscosity. Agglomeration of silica particles in composites was reduced with silica surface modification. Silica filler improves thermal stability and tensile strength of polyacrylate.

This paper provides broad spectrum of information depending on filler surface modification and latex preparation via in situ emulsion polymerization and properties with high amount of filler and monomer/water ratio with the aim that prepared latex is suitable for film formation and final application.

The phycocyanin is a pigment present in the microalga Spirulina that has been studied due to its applicability as food coloring; however, it can be used due to the ability to act as an emulsifier or stabilizer in function of its protein characteristic. The purpose of this paper is to use aqueous extracts of Spirulina containing phycocyanin (EP) as a substitute of additives in the production of ice creams.

The study was divided in two sections: first, the influence of addition of EP in ice cream bases (that represent the ice cream preparation before air incorporation step) and second, the influence of addition of EP in five ice cream formulations, in which the differences were the addition of EP in substitution of stabilizer, Chantilly or emulsifier, one at a time or in substitution of all additives together, by the EP.

The different ice creams developed presented centesimal composition according to Brazilian legislation in relation to the chemical parameters. The EP presented emulsifying and stabilizing activity in the ice creams formulations acting in substitution of emulsifier and stabilizer presented in the standard formulation, not influencing the overall acceptability of consumers.

The authors demonstrate that the aqueous extract of Spirulina containing phycocyanin can be used as a natural additive in ice cream in substitution of emulsifiers and stabilizers normally used in this product, contributing to produce more healthy foods, once phycocyanin is an protein of high nutritional value.

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.

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).

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.

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.

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

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.

Recent evidence suggests that especially processed foods may lead to undesirable metabolic effects in gut microbiota. The emulsifiers and artificial sweeteners that are added to processed foods may play a role in the progression of the diseases through the modulation of microbiota in mice. In this context, the purpose of this paper is to evaluate the effects of emulsifiers and artificial sweeteners.

This paper presents a narrative review of the effects of emulsifiers and artificial sweeteners which are mainly in consumed in the Western diet, to the gut microbiota by mainly focusing on the experimental studies.

Although in vivo studies and animal model studies showed various adverse effects of sweeteners and emulsifiers to microbiota, studies should be conducted in humans to investigate the effects of these food additives to human microbiota by making dietary interventions in the context of ethical rules.

In future, studies will allow us to draw more definitive conclusion whether human population consuming sweeteners and emulsifiers are at risk.

Silane cross-linkers have been used to strengthen the mechanical stabilities and friction resistance of plastic products. Therefore, the effect of silane cross-linkers on latex has been studied through preparing modified self-cross-linking long fluorocarbon polyacrylate latex. In this paper, nonionic surfactant alcohol ether glycoside (AEG1000) and anionic polymerizable surfactant 1-allyloxy-3-(4-nonylphenol)-2-propanol polyoxyethylene (10) ether ammonium sulfate (DNS-86) acted as mixed emulsifier and 3-(methacryloyloxy) propyltrimethoxysilane (KH-570) and bis (2-ethylhexyl) maleate (DOM) were used as functional monomers.

The modified acrylate polymer latex was synthesized through the semi-continuous seeded emulsion polymerization with methyl methacrylate (MMA), butyl acrylate (BA), dodecafluoroheptyl methacrylate (DFMA) and hydroxypropyl methacrylate (HPMA) as main monomers. Potassium persulfate (KPS) was applied to initiate polymerization reaction, nonionic surfactant AEG1000 and DNS-86 acted as emulsifier, KH-570 and DOM were used as functional monomers, respectively.

The optimum conditions of synthesizing the modified latex were the following. The mass ratio of monomers containing MMA, BA, DFMA, HPMA, KH-570 and DOM was 13.58:13.58:0.90:1.20:0.15:0.60, the usage of initiator KPS was 0.5% of the total weight of monomers and the amount of emulsifier was 7% of all monomers with AEG1000:DNS-86 = 1:1. The results indicated that the conversion of monomer was 99% and the coagulation was about 2.0%.

The resultant latex was modified silane cross-linker KH-570 and DOM, which positively affected the comprehensive properties of latex and its film. Apart from this, the novel mixed emulsifier was used to improve the size and distribution of latex particles and reduce environmental problems caused by the use of emulsifiers.

Self-crosslinked long fluorocarbon acrylate polymer latex has good hydrophobic and oleophobicity, weather resistance, aging resistance, stability and other excellent properties, which make the polymer be widely used in coatings, dyes, adhesives and other products. The purpose of this study is to prepare self-crosslinked long fluorocarbon acrylate polymer latex via semi-continuous seeded emulsion technology and carry out comparative study on two different cross-linked monomers.

Methyl methacrylate (MMA) and butyl acrylate (BA) were used as the main monomers, dodecafluoroheptyl methacrylate (DFMA) as the fluoromonomer, hydroxypropyl methacrylate (HPMA) and N-methylol acrylamide (NMA) as cross-linked monomers, and 1-allyloxy-3–(4-nonylphenol)-2-propanol polyoxyethylene (10) ether (ANPEO10) and 1-allyloxy-3–(4-nonylphenol)-2-propanol polyoxyethylene (10) ether ammonium sulfate (DNS-86) as compound emulsifiers via the semicontinuous-seeded emulsion polymerization.

The properties of the polymer emulsions, which are prepared with two different cross-linked monomers, are compared and discussed, and it is concluded that HPMA is more suitable for the preparation of self-crosslinked polymer emulsions. The formula of the polymer latex is ANPEO10: DNS-86 = 1:1, and the mass ratio of the monomers used in the polymer is MMA: BA: DFMA: HPMA = 14.40:14.40:0.60:0.60.

Self-crosslinked long fluorocarbon acrylate polymer latex can be used in many fields such as coatings, dyes, adhesives and other products.

The self-crosslinked long fluorocarbon acrylate polymer latex is prepared by mixing the nonionic emulsifier ANPEO10 and the anionic emulsifier DNS-86 when potassium persulfate is used as the thermal decomposition initiator and the semicontinuous-seeded emulsion technology is adopted and the comparative study on two different cross-linked monomer is carried out, which is not reported in the open literatures.