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Article
Publication date: 1 February 1974

John Wren

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…

Abstract

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 :—

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Nutrition & Food Science, vol. 74 no. 2
Type: Research Article
ISSN: 0034-6659

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Article
Publication date: 7 June 2020

Yilu Gong, Tantan Shao and Lijun Chen

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…

Abstract

Purpose

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.

Design/methodology/approach

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.

Findings

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.

Originality/value

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.

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Pigment & Resin Technology, vol. 50 no. 1
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 21 September 2012

Ahmed M. Al‐Sabagh, Salah A. Khalil, Abdellatief Abdelrahman, Notaila M. Nasser, Mahmoud R. Noor Eldin, Marwa R. Mishrif and Mohamed El‐Shafie

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…

Abstract

Purpose

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.

Design/methodology/approach

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.

Findings

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.

Originality/value

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.

Details

Industrial Lubrication and Tribology, vol. 64 no. 6
Type: Research Article
ISSN: 0036-8792

Keywords

Open Access
Article
Publication date: 13 October 2021

Zrinka Buhin Šturlić, Mirela Leskovac, Krunoslav Žižek and Sanja Lučić Blagojević

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…

Abstract

Purpose

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.

Design/methodology/approach

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.

Findings

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.

Originality/value

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.

Details

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

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Article
Publication date: 13 December 2019

Ellen Francine Rodrigues, Luana Paula Vendruscolo, Kimberly Bonfante, Christian Oliveira Reinehr, Eliane Colla and Luciane Maria Colla

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…

Abstract

Purpose

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.

Design/methodology/approach

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.

Findings

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.

Originality/value

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.

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British Food Journal, vol. 122 no. 2
Type: Research Article
ISSN: 0007-070X

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Article
Publication date: 4 November 2020

Tantan Shao, Xiaolong Chen and Lijun Chen

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…

Abstract

Purpose

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.

Design/methodology/approach

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.

Findings

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%.

Originality/value

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.

Details

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

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Article
Publication date: 1 June 1997

Alex Wegmann

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…

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Abstract

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.

Details

Pigment & Resin Technology, vol. 26 no. 3
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 4 July 2016

Wen Li, Zhongbin Bao, Lijun Chen and Dongshun Deng

At present, the conventional method of preparing cationic fluorinated acrylic latex is to emulsify copolymerised monomers with cationic surfactants. However, there has…

Abstract

Purpose

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).

Design/methodology/approach

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.

Findings

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.

Practical implications

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

Originality/value

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.

Details

Pigment & Resin Technology, vol. 45 no. 4
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 9 April 2019

Elif Inan-Eroglu and Aylin Ayaz

Recent evidence suggests that especially processed foods may lead to undesirable metabolic effects in gut microbiota. The emulsifiers and artificial sweeteners that are…

Abstract

Purpose

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.

Design/methodology/approach

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.

Findings

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.

Originality/value

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

Details

Nutrition & Food Science , vol. 49 no. 5
Type: Research Article
ISSN: 0034-6659

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Article
Publication date: 1 February 2009

M.H. Abo-Shosha, F.A. Nassar, K.M. Haggag, Z. El-Sayed and A.G. Hassabo

Condensates of stearic (St), palmitic (Pa) or myristic (My) acids with polyethylene glycols (PEG) 300, 400, 600, 2000 or 6000, are utilized as emulsifiers for kerosene …

Abstract

Condensates of stearic (St), palmitic (Pa) or myristic (My) acids with polyethylene glycols (PEG) 300, 400, 600, 2000 or 6000, are utilized as emulsifiers for kerosene ∓ in ∓ water pigment printing pastes. Pastes based on condensates of PEG 300 or 400 are unstable while the others are stable. Rheology of stable pastes, aside from those based on a commercial emulsifier, are of a non ∓ Newtonian, shear thinning ∓ thixotropic flow. The order of the flow properties of pastes enhanced are found. Cotton pigment prints using the nine pastes are sharp and of comparable handle, colour strength and color fastness to those based on a paste of either a commercial emulsifier or synthetic thickener (except for Pa∓6000). The pigment prints of 65/35 cotton/polyester are sharp only upon using pastes of commercial emulsifier, synthetic thickener, St∓600, St∓2000, St∓6000 and My∓2000. After 7 days of storing, all pastes are stable with increased apparent viscosities and induced color strength on both cotton and blended fabrics.

Details

Research Journal of Textile and Apparel, vol. 13 no. 1
Type: Research Article
ISSN: 1560-6074

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