cosmetiscope - october 2014 - vol. 20 no. 8

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(Continued on page 4) The Greening of Emulsions … by Joseph Albanese November 5th The Terrace at Biagio’s, Paramus, NJ NYSCC NOVEMBER CHAPTER MEETING Let’s Start with a Joke V egetarian: “I’m not a vegetarian because I think eating meat is unhealthy for me. It’s because raising cattle is bad for the planet. Cow flatulence adds to the ozone layer and the clearing of land for the raising of cattle means fewer green plants producing oxygen through photosynthesis. What are you doing to help the environment?” Ron White: “Personally, I'm eating the cows as fast as I can. BUT I’M ONLY ONE MAN!” Now Let’s Get Serious! As a cosmetic chemist developing a new emulsion is there anything that you can do to help save the environment? Might I suggest that in your daily work you keep in mind the Twelve Principles of Green Chemistry? 1 See Figure 1. For this brief article, let’s limit the discussion by focusing on Principle No. 6, which calls us to “Design for Energy Efficiency – Minimize the energy requirements of chemical processes and conduct synthetic methods at ambient temperature and pressure if possible.” An early pioneer in this area is Dr. T. Joseph Lin who published his initial work on Low Energy Emulsification (LEE) in 1978, 2 long before the EPA came out with their Twelve Principles (see Figure 2). Dr. Lin’s research taught that stable emulsions could be prepared successfully even if all of the external phase is not at elevated temperature. In the case of an oil-in-water (O/W) emulsion, the LEE procedure calls for only a portion of the external water phase (β phase) to be heated before combining it with the hot internal oil phase. This emulsion concentrate is then diluted to the desired concentration with the remaining ambient temperature water (α phase) to cool down the emulsion. The rate of cooling has a profound effect on particle size of the internal phase and overall acceptability of the final emulsion. In his more recent publication, 3 a delightful and educational treatise, Dr. Lin explains, in story-telling fashion, that by carefully controlling processing variables (pV) and component variables (cV also known as ingredients) LEE optimizes the desired properties (Zp) of your emulsion. In short, LEE requires less energy input to create stable emulsions, thus it saves money, reduces processing time, increases plant capacity, and reduces the carbon footprint of your plant without having to reformulate or invest in new equipment. Dr. Lin also stresses the “less is more” philosophy. Namely, too much of a good thing can be detrimental to achieving your goals. Later, we will advance this pioneering research of Dr. Lin’s to show how you can include specific types of polymers into your formula that will enable you to create emulsions quickly, with little to no surfactant emulsifiers and requiring less energy input, but first, let’s take a step back in time. New York Society of Cosmetic Chemists www.nyscc.org OCTOBER 2014 • Vol. 20 No. 8

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Page 1: Cosmetiscope - October 2014 - Vol. 20 No. 8

(Continued on page 4)

The Greening of Emulsions … by Joseph Albanese

November 5th • The Terrace at B iagio ’s , Paramus, NJN Y S C C N O V E M B E R C H A P T E R M E E T I N G

Let’s Start with a Joke

Vegetarian: “I’m not a vegetarian because I think eating meat is unhealthy for me. It’s because raising cattle is bad for the planet.Cow flatulence adds to the ozone layer and the clearing of land for the raising of cattle means fewer green plants producing oxygenthrough photosynthesis. What are you doing to help the environment?”

Ron White: “Personally, I'm eating the cows as fast as I can. BUT I’M ONLY ONE MAN!”

Now Let’s Get Serious! As a cosmetic chemist developing a new emulsion is there anything that youcan do to help save the environment? Might I suggest that in your daily work youkeep in mind the Twelve Principles of Green Chemistry?1 See Figure 1. For this briefarticle, let’s limit the discussion by focusing on Principle No. 6, which calls us to“Design for Energy Efficiency – Minimize the energy requirements of chemicalprocesses and conduct synthetic methods at ambient temperature and pressure ifpossible.” An early pioneer in this area is Dr. T. Joseph Lin who published hisinitial work on Low Energy Emulsification (LEE) in 1978,2 long before the EPAcame out with their Twelve Principles (see Figure 2). Dr. Lin’s research taught thatstable emulsions could be prepared successfully even if all of the external phaseis not at elevated temperature. In the case of an oil-in-water (O/W) emulsion, theLEE procedure calls for only a portion of the external water phase (β phase) to beheated before combining it with the hot internal oil phase. This emulsion concentrateis then diluted to the desired concentration with the remaining ambient temperaturewater (α phase) to cool down the emulsion. The rate of cooling has a profoundeffect on particle size of the internal phase and overall acceptability of the finalemulsion. In his more recent publication,3 a delightful and educational treatise, Dr. Linexplains, in story-telling fashion, that by carefully controlling processing variables(pV) and component variables (cV also known as ingredients) LEE optimizes thedesired properties (Zp) of your emulsion. In short, LEE requires less energy inputto create stable emulsions, thus it saves money, reduces processing time, increasesplant capacity, and reduces the carbon footprint of your plant without having toreformulate or invest in new equipment. Dr. Lin also stresses the “less is more”philosophy. Namely, too much of a good thing can be detrimental to achieving your goals. Later, we will advance this pioneering research of Dr. Lin’s to show how you can include specific types of polymers into your formulathat will enable you to create emulsions quickly, with little to no surfactant emulsifiers and requiring less energy input, but first, let’s takea step back in time.

New York Society of Cosmetic Chemists www.nyscc.org

OCTOBER 2014 • Vol. 20 No. 8

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2014 NYSCCBOARD OF

DIRECTORS &PROGRAM CHAIRS

CHAIRSteve [email protected]

CHAIR-ELECT Kim Burch

(609) 443-2385 [email protected]

TREASURER Sonia Dawson

[email protected]

TREASURER-ELECT Marie Thadal(609) 712-3716

[email protected]

SECRETARY Jenna Jelinski(201) 396-8431

[email protected]

ADVISOR Steve Herman(973) 479-5702

[email protected]

HOUSE Andrea Guerrero

[email protected](862) 324-1063

MEMBERSHIP Amy Marshall (908) 806-4664

[email protected]

PROGRAMCathy Piterski(678) 730-1643

[email protected]

SPECIAL EVENTS John Denoia(845) [email protected]

COSMETISCOPE EDITOR Roger McMullen

[email protected]

COSMETISCOPEADVERTISING

Bret [email protected]

COSMETISCOPEEMPLOYMENT Jason O’Neill(631) 252-2939

[email protected]

Abstract:

Amorphous polymeric materials are used in a wide array of technologiesranging from organic electronics to structural components of airplanes.As many of these technologies trend towards nanometer length scales,

it is imperative to have a fundamental understanding of the properties of polymer glasses at the lengthscale, geometry, and environment of the application. Recent work in polymer physics shows that thestructural relaxation time near a free surface of a thin polystyrene film is significantly different from that ofthe bulk polymer. This can have a large influence on their properties. For instance, studies have shown thatpolystyrene thin films exhibit a decreased glass transition temperature (Tg) as the thickness decreases below60 nm. A puzzling aspect of this phenomenon is that most studies indicate that there is no molecular weightdependence on Tg reduction in supported films, while the same phenomenon in freestanding polystyrenefilms shows strong molecular weight dependence. In this study, we use cooling-rate dependent Tgmeasurements to indirectly probe the relaxation dynamics of thin polystyrene films, and show they aredirectly influenced by the dynamics of the free surface. Furthermore, we show that the relaxation dynamicsof supported polystyrene films slow down slightly as the molecular weight of polystyrene is increased.

Biography:

Ethan Glor is a Ph.D. candidate in Chemistry at the University of Pennsylvania. His current work under Dr.Zahra Fakhraai consists of gaining new insight into the dynamics of amorphous polymeric materials in thehopes of eventually preparing polymeric glasses with high density and high kinetic stability. Ethan was

awarded an Honorable Mention for the National Science Foundation Graduate Research Fellowship in 2013, andis a 2011 graduate of Haverford College with a B.S. in Chemistry.

E D U C A T I O N A L H O U R S P E A K E R

Speaker: Ethan Glor Topic: Kinetic Facilitation of Interfaces in Thin Entangled Polymer Films

N Y S C C M O N T H L Y C H A P T E R M E E T I N G

The Synthesis and Analysis of Functional PolymersNovember 5, 2014 • The Terrace at Biagio’s, Paramus, NJ

293 County Road 62 (Paramus Road), Paramus, NJ 07652Open registration: 4:00 PM

Educational Hour: 4:30 PM • Dinner: 5:30 PMChapter Meeting Speaker: 6:30 PM

A t t e n t i o n M e m b e r sUnemployed and Emeritus members may continue to attend monthly meetings free of charge.Please contact the registration booth upon arrival. Unemployed members may also continuetheir membership free of charge by submitting the renewal form with unemployment details.

Please remember that the SCC Employment Service is here to assist you.Contact: Jason O’Neill • E-Mail: [email protected]

Group DiscountThe NYSCC has decided to offer a group discount of 15% to

companies who send 5 or more employees to a monthly meeting. Allfive employees would need to be registered at the same time to receive the discount. Once purchased, registrations are non-refundable.

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Upcoming SCC Continuing Education

November 7 Scale Up & Processing

November 13 Molecular Biology: Gene Expression for the Cosmetic Chemist

December 10 Fragrance As A Science

December 10 Regulatory Update

For more information, please visit www.scconline.org.

Abstract:

Poly(amide)-based dendrimers have shown potential as scaffolds for celldelivery agents when used in conjunction with the peptide gH625, apeptide encompassing 625–644 residues of the glycoprotein H of herpes

simplex virus 1. The peptide has been shown to transport cargo across cellmembranes as well as have mild antiviral activity in vitro. Dendrimers werechosen as a scaffold due to the modular nature of their synthesis. The synthesis of mono-functionalized dendrimers has been explored and optimized by our researchgroup. It has been shown that when covalently attached to the termini of a second-generation (one having18 termini) dendrimer scaffold, the chosen peptide enters cells more efficiently. Varying the generation ofdendrimers may give dendrimer-based delivery systems an advantage over traditional linear polymericsystems. An array of dendrimer scaffolds with varying termini onto which the active peptide can be attachedwas synthesized. For comparison testing, linear analogs to the first and second-generation dendrimers weresynthesized. Cell studies are planned to determine the most efficient transmembrane transport system.

Biography:

Elizabeth Kaufman is a researcher and Ph.D. candidate in the Molecular Design Institute of the NYUGraduate School of Chemistry. Her current research under Dr. Marcus Weck, centers on biologicalapplications of the class of perfectly branched molecules known as dendrimers, particularly with regard to

the cellular uptake of such systems to optimize a cellular delivery system. Kaufman was granted a McCrackenAward in 2011 and became a Kramer Award recipient in 2014. Kaufman's undergraduate research focused onsynthesis of organically templated gallium sulfates. Kaufman is a 2011 graduate of Haverford College with aB.S. in Chemistry.

Speaker: Elizabeth Kaufman Topic: The Effect of Generation on Cellular Uptake of Dendrimers

N Y S C C C H A P T E R M E E T I N G S P E A K E R

NYSCC MONTHLY MEETING REGISTRATION:• Online: www.nyscc.org

• For questions, please contact: John Carola at [email protected].

CHAPTER MEETING COST:Pre-registered SCC members: $35 ($70 at door) • Pre-registered non-SCC members: $75 ($110 at door)

Students: $10 ($50 at door) • Emeritus: Free ($40 at door)Register online at: www.nyscc.org.

[email protected]+1 (855) 776-7769www.rossow-usa.com

R E S O U R C E S

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Page 4: Cosmetiscope - October 2014 - Vol. 20 No. 8

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The History of Emulsions Reportedly, Galen developed the first emulsion in ancient Greece back in 131–201 AD and the Egyptianscombined beeswax and borax to make emulsions. Why does this early love affair with emulsions continueto this day? Simply because emulsions are an elegant and cost effective way to easily and elegantly delivera wide range of active ingredients because water is less expensive than cosmetic oils. Emulsions are also awonderful vehicle to deliver oil soluble actives with a non-greasy skin feel. Emulsions can dilute pharmaceuticaland OTC actives down to safe, yet still effective, levels. An emulsion is a mixture of two or more immiscible liquids. When oil is the internal or dispersed phaseit is known as an oil-in-water, or O/W, emulsion. When oil is the external or continuous phase, then it is awater-in-oil, or W/O, emulsion. Without going into details, there are several techniques for determining the

kind of emulsion at hand. They are the dilution test, conductivity test, dye solution test, RI Test, and filterpaper test. Multiple phase emulsions are also possible. The particle or droplet size of the internal phase is one way of knowing whether or not you have anemulsion or something else. If the particle is very large, then it is more likely a dispersion or suspension. Ifthe particle is very small, then it is likely an emulsion or possibly even a solution. The smaller the particlesize the more stable the formula. The most stable emulsions are microemulsions. In fact, when the dispersed phase is 0.01–0.2 µm insize the emulsion is thermodynamically stable. Microemulsions are characterized by their transparencysince the droplet size is <25% of the wavelength of visible light. They normally require very high surfactantlevels, which ultimately results in very low O/W interfacial tension. Because of the high surfactant levelsthey require lower energy input. The focus of this article will be on the more commonly found macroemulsions. The range of the particlesin the dispersed phase is 0.2–50 µm. These formulas are inherently kinetically stable, but ultimately unstabledue to the Second Law of Thermodynamics. They are opaque in appearance and require relatively high-energy input to create. Figure 3 shows the common ingredients and their approximate use-levels often foundin a typical macroemulsion.

Traditional Ways to Make an Emulsion As a highly educated professional and experienced formulator you know that oil and water do not mix.

The Greening of Emulsions (Continued from page 1)

Twelve Principles of Green Chemistry1. Prevention – It’s better to prevent waste than to treat or clean up waste afterwards.2. Atom Economy – Design synthetic methods to maximize the incorporation of all materials used in the process into thefinal product.

3. Less Hazardous Chemical Syntheses – Design synthetic methods to use and generate substances that minimize toxicityto human health and the environment.

4. Designing Safer Chemicals – Design chemical products to affect their desired function while minimizing their toxicity.5. Safer Solvents and Auxiliaries – Minimize the use of auxiliary substances wherever possible make them innocuous whenused.

6. Design for Energy Efficiency – Minimize the energy requirements of chemical processes and conduct synthetic methodsat ambient temperature and pressure if possible.

7. Use of Renewable Feedstocks – Use renewable raw material or feedstock whenever practicable.8. Reduce Derivatives – Minimize or avoid unnecessary derivatization if possible, which requires additional reagents andgenerate waste.

9. Catalysis – Catalytic reagents are superior to stoichiometric reagents.10. Design for Degradation – Design chemical products so they break down into innocuous products that do not persist in

the environment.11. Real-time Analysis for Pollution Prevention – Develop analytical methodologies needed to allow for real-time, in-process

monitoring and control prior to the formation of hazardous substances.12. Inherently Safer Chemistry for Accident Prevention – Choose substances and the form of a substance used in a chemical

process to minimize the potential for chemical accidents, including releases, explosions, and fires.Source: http://www.epa.gov/sciencematters/june2011/principles.htm

Figure 1.

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They exemplify the very definition of immiscible.Significant energy input is required to create ahomogeneous dispersion of these two immiscibleliquids. High-shear homogenization, impingementwith a Gaulin homogenizer, or ultrasonic vibrationcombined with propeller and/or sweep-blade agitationare several ways to reduce the droplet size of thedispersed phase. By disrupting the cohesive forces ofthe droplet during this process a homogeneous,uniform size distribution is achieved. However, oncethe agitation stops syneresis, flocculation, coalescence,agglomeration, Ostwald ripening, creaming, etc. can allhappen quickly. In conventional emulsion preparations

heat energy is added to reduce viscosity and decrease interfacial tension. As mentioned earlier, the LEEprocedure significantly reduces the amount of heat required. Despite the amount of mechanical and heat energy applied, an emulsion will still fall apart too quicklywithout the addition of surface-active agents to further reduce the interfacial tension between the dispersedand the continuous phases. Anionic surfactants will arrange themselves with their hydrocarbon tail in theoil droplet and their negatively charged carboxylated ionic heads in the continuous water phase. The sterichindrance and electrical double layer repulsion provided by this mono-molecular layer of surfactantssurrounding oil droplets prevents their contact and coalescence. Deciding what surfactants to use is a challenge. In 1947, Griffin developed a method known as theHydrophilic-Lipophilic Balance (HLB) System to help formulators. The HLB of a surfactant equals the mole% of the hydrophilic group divided by five. The maximum HLB of a surfactant is 20. One must also knowthe required HLB of the cosmetic oils in the formula in order to emulsify them. From the known HLB valuesgiven in tables, an equation must be calculated to determine the use-levels that strike the right balance

between the two. This system really works only for nonionicsurfactants that are either ethylene oxide-propylene oxidecopolymers (Pluronics, Poloxymers), sorbitan esters with lowHLB values (Spans), or ethoxylated derivatives of sorbitanesters with high HLB values (Tweens). Another way, whichworks with almost any type of surfactant, is the oil solubilitymethod, which comes again from Dr. T.J. Lin. It involvestitrating water into the hot oil phase (containing an emulsifier)with mixing until it no longer turns clear. The best emulsifieris the one that incorporates the highest amount of waterbefore remaining cloudy.4

Problems may arise from using surfactants as emulsifiers.Excessive levels may lead to the formation of clear microemulsions. Some surfactants cause dryness andskin irritation. Nonionic surfactants may render preservative systems ineffective to control microbialproliferation. Surfactants may tend to emulsify and wash away sunscreen actives upon immersion in waterleaving skin unprotected. Because of concerns like these it is sometimes wise to consider alternativeemulsifiers. Emulsifiers may also come in the form of hydrophilic colloids, amphipathic polymers (to bediscussed later), or two-faced Janus particles to form Pickering Emulsions.5

Although there are many exceptions, Bancroft’s Rule states that the phase in which the emulsifier is themost soluble becomes the external phase by lowering the interfacial tension on that side of the film.6 Withcareful observation during the preparation of emulsions one will discover that the viscosity of an emulsionwill change dramatically at a certain temperature. The point at which this occurs is known as the PhaseInversion Temperature, or PIT. Sometimes it is referred to as the Phase Transition Temperature, or PTT. Itdepends upon the concentration of surfactants and other emulsifiers present. Viscosity goes up and electricalconductivity drops at the PIT. If the PIT is not above the storage temperature the emulsion will be unstable. One less commonly employed technique for hot process water-in-oil emulsification is to create aninverse emulsion by adding the external water phase slowly to the oil phase. The initial water-in-oil emulsioninverts as the remaining water is added.

Figure 3: A typical O/W macroemulsion.

Figure 2: A comparison of conventional versus low energy emulsification (LEE). From T.J. Lin, Reference 3.

(Continued on page 6)

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A Lamellar Gel Network (LGN) is formed by combining both high and low HLB surfactants, whichraises yield value and promotes emulsion stability. Low HLB surfactants like fatty alcohols create structureand thicken. Glyceryl monostearate and sorbitan monostearate are easier to swell than fatty acids andreduce the amount of high HLB surfactant needed. More polar high HLB surfactants, such as cetearylglucoside, hydrogenated lecithin, sodium stearoyl glutamide, sodium stearoyl methyl taurate, sodiumstearoyl lactylate, or behenyl trimethylammonium choridetend to swell the low HLB surfactant to promote lamellarbilayer formation. Ethoxylated surfactants are not verysoluble at, or above, their cloud point. So creating stableemulsions under those processing conditions is notpossible. Purposely raising the carbon chain length ofeither the low HLB or the high HLB surfactant, or the oilphase, will raise the PTT. High shear mixing or homogenization for prolongedperiods at elevated temperatures will decrease the size ofoil phase droplets too much. If oil droplets become toosmall, and their numbers too many, their increasedsurface area becomes too much for the surfactant to coverand therefore unable to form LGNs. This is a prime example of what Dr. Lin calls the “less-is-more” principle.In this example, less homogenization creates more stability. LGNs are viscoelastic and shear-thinning foreasy dispersal and application to the skin. Most O/W skin care emulsions sold globally are based on LGNsstabilized with polymers.7

Enter Polymeric Emulsifiers An early article by Dr. R. Lochhead covered the utility of including polymers in emulsions.8 Syntheticpolymeric thickeners may be homopolymers, copolymers, or crosspolymers. Polymers of acrylic acid, orPAAs, are especially useful in most any kind of formulation, which contains some water. Perhaps the mostwidely used example of this type of polymer is the frequently used homopolymer, carbomer. Such non-associative polymers like carbomer and acrylates copolymer work to stabilize emulsions by thickening thewater phase. Introduced more than a decade ago, hydrophobically modified copolymers and crosspolymersof acrylic acid added various lipophilic side chains to the hydrophilic backbone. All PAAs thicken by intra-and intermolecular chain entanglement, but added hydrophobic moieties have an aversion to water and agreater affinity to one another thereby creating polymer-polymer non-covalent cross-links. This forms amatrix that can profoundly influence rheological properties. These hydrophobes shield the polymer fromanionic-cationic polymer interactions that precipitate neutral polyelectrolyte complexes.9 Associative PAAsalso provide: greater tolerance to electrolytes, emulsification properties, a more conditioned skin-feel, rapidrelease of oil phase upon contact with the salts present on skin and other improved performance attributes.

The Greening of Emulsions (Continued from page 5)

Call for Papers

The Cosmetiscope editorial committee invites all interested parties to submit featuretechnical articles for publication in the NYSCC monthly newsletter. Authors offeature articles are eligible to win the prestigous NYSCC Literature Award

($1,000) for the best front-page article published during the calendar year. Also,authors receive $200 reimbursement to attend a theatrical performance of their choice.Writing an article for your peers is a very rewarding experience, both personally andprofessionally, and would reserve your place in NYSCC history. You may choose whatevertopic you feel would be interesting to fellow colleagues in our industry. We alsowelcome any other types of commentaries or articles that may be published in theCareer Corner, Technical Tidbit section, or as a Letter to the Editor. Please send correspondence to: [email protected].

Figure 4: An example of an associative thickener used in emulsions: acrylates/vinyl

isodecanoate crosspolymer.

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Two exceptional examples of this newer type of PAA rheology modifier with strong emulsificationproperties are acrylates/vinyl isodecanoate crosspolymer (powder)10,11 and acrylates/palmeth-25 acrylatecopolymer (liquid).12,13 Like others in this class they are multi-functional hydrophobically modified (seeFigure 4) alkali swellable associative rheology modifiers with an affinity for both oil and water, and provide

finished products with the desirable shear-thinningrheology for easy dispensing from packaging and topicalapplication onto hair and skin. Alky side chains provideassociation with oil droplets and the potential for increasedpolymer interactions. The 25 moles of ethoxylation onacrylates/palmeth-25 acrylate copolymer includes siteswhere hydrogen bonding to adjacent polymer chains andwater also become possible. Unlike carbomer, these“Alkylated Carbomers” not only swell to form hydrogelsthat pack into the water phase to thicken it, but alsosurround the dispersed phase and prevent coalescence

by stearic hindrance. High molecular weight polymeric emulsifiers bring attributes that low-molecular-weight surfactants cannot (see Figure 5). Normally, when a traditional emulsifier is added to an emulsion system, it breaks up the oil phase,increasing the number of droplets and reducing them in size. The photomicrographs in Figure 6, taken withinminutes after completing a simple cold process emulsion, shows how increasing the level of the polymericemulsifier, acrylates/palmeth-25 acrylates copolymer, has similar effects. These polymers also help regulate

viscosity drift on storage under various temperatures.One predictor of longer-term emulsion stability is tocompare the viscosity at 25 ºC and again at elevatedtemperature. A viscosity decrease of 20% for every 10ºC above 25 ºC is usually acceptable. A cause ofconcern might be if the measured viscosity at 45 ºC is>50% lower than the value at 25 ºC.

Acrylates/palmeth-25 acrylates copolymer canalso emulsify oils with a wide range of required HLBvalues. Just as in traditional hot process emulsions,increasing the concentration of the oil phase increasesviscosity. Furthermore, the hydrophobic modificationto the acrylate backbone and the associative nature ofthe polymer significantly increases yield value over

non-associative carbomer homopolymers. It should be noted that there is not a direct correlation betweenviscosity and yield value. A shear-thinning rheology is typical of cosmetic emulsions. They may be time-independent pseudoplasticin nature, which may be obtained using polymers of acrylic acid. Or, time-dependent thixotropic emulsionscharacterized by the extra time required for viscosity to recover following the cessation of shear. Shear-thinning viscosity permits products to flow easily from packaging and distribute evenly on the substrate.Various gums, clays, organoclays, silicas, cellulosics, and polyethylenes, can achieve one or the other typeof rheological profile. Making cold process emulsions with either of these polymers is a simple three-step procedure: 1) dispersethe polymer, 2) homogenize the oil and water phases and 3) neutralize the polymer with a suitable base.The potential for developing a heated or cold process one-pot making procedure for emulsions is possibleusing either of these two examples of hydrophobically modified polymers. Acrylates/vinyl isodecanoatecrosspolymer may be added to water or oil phases in either a side kettle or directly into the main mix tank.Acrylates/palmeth-25 acrylates copolymer goes into water virtually instantaneously after which eachsubsequent ingredient can be added on top with adequate agitation. Of course, the possibility of cold process emulsification hinges upon the melting point of any waxesthat may be in the formula. All, or at least a sufficient portion, of the oil phase might have to be heated toincorporate these materials. In that case one may use the LEE procedure in combination with amphipathicpolymers as primary or secondary emulsifiers.

Figure 5: Scheme illustrating the difference between (a) a traditional emulsion thickened with carbomer versus (b) a polymeric emulsion

thickened with an alkylated carbomer(acrylates/vinyl isodecanoate crosspolymer).

Figure 6: Photomicrographs (500x) taken within minutes after completing a simple cold process emulsion with 20% mineral oil and a thickener/emulsifier, acrylates/palmeth-25 acrylates copolymer. (a) 5% polymer, (b) 2.5% polymer, and

(c) 1.25% polymer. Since these photographs were taken immediately after the emulsification procedure,this demonstrates that polymer is acting similar to

a surfactant in its ability to disrupt

(Continued on page 8)

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The Greening of Emulsions (Continued from page 7)

Things to Keep in Mind Macroemulsions are thermodynamically unstable. The key to creating the most stable O/W emulsionsis retarding the interaction of dispersed oil droplets. To start, the proper amount of mechanical or heat energyrequired for your formula must be determined. Increasing the viscosity and yield value of the formula willimprove the stability. Selecting the best emulsifier(s) is critical to success. The addition of polymers willincrease the viscosity of the water phase. Oil phase thickeners are less readily available and can requirevery high temperatures to incorporate. Reducing the droplet size and/or the concentration of the dispersedphase can significantly increase viscosity leading to a more stable emulsion. Not mentioned earlier is thatlow levels of electrolytes may actually help stabilize an emulsion. Perfumes can have a large effect onviscosity. Also, be cautioned to avoid aeration during the process. Entrained air bubbles adds a third gaseousphase creating a multiple emulsion and a less stable situation.

Polymers that Help Emulsions “Go Green” In conclusion, with hydrophobically modified alkali swellable amphipathic polymers one may developan emulsion with even greater energy efficiency than what may be realized following Dr. Lin’s LEE process.Cold process emulsification with polymeric emulsifiers provides even greater savings and increasedmanufacturing capacity. In keeping with Principle No. 6, let’s all try to develop robust formulas that minimizethe environmental impact of our manufacturing processes. I’d rather do that than drive a Prius to make mycontribution to saving Mother Earth for future generations. A tip of the ol’ cap to all the Prius owners readingthis article. You are better persons than me.

Bibliography1. www.epa.gov, “12 Principals of Green Chemistry” originally published by Paul Anastas, Ph.D. and JohnWarner, Ph.D. in Green Chemistry: Theory and Practice, Oxford University Press: New York, 1998.

2. T.J. Lin, “Low-energy emulsification – I. Principles and applications,” J. Soc. Cosmet. Chem., 29, 117-125 (1978).3. T.J. Lin, Manufacturing Cosmetic Emulsions: Pragmatic Troubleshooting and Energy Conservation,Allured Books: Carol Stream, IL (2010).

4. T.J. Lin, H. Kurihara, and H. Ohta, “Prediction of optimum O/W emulsification via solubilizationmeasurements,” J. Soc. Cosmet. Chem., 28, 457-479 (1977).

5. J. Albanese, “Pickering emulsions,” Cosmetiscope, 14(4), 12 (2008).6. K. Klein, Formulating Cosmetic Emulsions, SCC Continuing Education Course, 1998.7. G. Deckner and T. O’Lenick, Lamellar Gel Network Lab Workshop, C&T Summit, Philadelphia, 2014.8. R.T. Lochhead, “The use of polymers in emulsions,” J. Cosmet. Sci., 58, 578 (2007).9. J.V. Gruber, “Synthetic polymers in cosmetics” in Principles of Polymer Science and Technology in

Cosmetics and Personal Care, Eds. D.E. Goddard and J.V. Gruber, Cosmetic Science and TechnologySeries, Marcel Dekker: New York (1999).

10. “STABYLEN 30: A Thickening, Suspending and Emulsifying Agent for Emulsions and Surfactant Systems,”3V Technical Report No. 1 – Edition 2/1.

11. “Formulation of O/W Emulsions with STABYLEN 30,” 3V Technical Report – Edition 1/2.12. “SYNTHALEN® W2000: A Liquid Thickener for Cosmetic Applications,” 3V Technical Report No. 6 –

Edition 4/2.13. J. Albanese, “Energy efficient emulsification using hydrophobically modified alkali swellable amphipathic

polymers,” Carolina SCC Chapter, Naturally Kiawah Symposium, 2014.

About the Author:

JJ oe is currently the Technical Marketing Manager Personal Care at 3V Inc.During his career in the personal care industry Joseph Albanese worked forAvon, Shulton, and Colgate-Palmolive in both process and product development

groups. His employment on the supply side of the industry included more than12 years at GAF/ISP where he went from formulation chemist to manager of theHair Care Applications/Tech Service lab. He is a graduate of the F.D.U. CosmeticScience M.A. Program. He has been a member of the SCC since 1984 and iscurrently Area I Director.

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The board of directors of the Society of Cosmetic Chemists (SCC) has announced that it will host the 29th IFSCC Congress on Oct. 23–26, 2016, in Orlando, Florida, USA. The theme of the meeting is “Beyond Dreams into New Frontiers—Inspire, Imagine, Innovate,” and the event will be

held at the Dolphin Hotel at the Walt Disney World Resort.

The organizing committee for the event includes Guy Padulo (Kobo Products Inc.),Colleen Rocafort (BASF Corp.), and Amy Wyatt (Chanel Inc.), with Padulo chairing the committee, Rocafort chairing the exhibition, and Robert Lochhead, Ph.D.,

serving as honorary chair of the event.

To help promote the event, the SCC will be using QR Code technology. This technology enablesindividuals to scan the QR code with their smart phones, tablets, and iPads and receive an informativemessage. So far, two QR Codes have been introduced, with more planned over the next two years. There will be general sessions, a poster session, an exhibition, and three social events. The Committeeon Scientific Affairs will again be responsible for the scientific program including both podium and posterpresentations. It is expected that the call for papers of both podium and poster presentations will see a recordnumber of abstracts submitted. The 2016 congress organizing committee is currently soliciting sponsorships.The committee is also seeking companies interested in participating at the exhibition that will take place inconjunction with the congress. The Pacific Hall will again be the venue with 50,000 square feet ofcolumnless space.

More information on the congress will be forthcoming including a call for papers, the exhibitor prospectus, and the launch of the event's website.

See more at:http://www.cosmeticsandtoiletries.com/networking/eventcoverage/161263995.html#sthash.iEC1haPW.dpuf

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In the New York SCC Region:

n SENIOR CHEMIST I The Estée Lauder Companies, located in Melville, NY, has a position open for a senior chemistresponsible for the development of new skin care products or modifications of existing ones.

n APPLICATION CHEMIST – HAIR AND BODY CARE BASF, The Chemical Company, is seeking an application chemist for their R&D department in Tarrytown, NY.

n ACCOUNT MANAGER PERSONAL CARE – EAST REGION BASF, The Chemical Company, is seeking an account manager for its personal care business to coverthe eastern region of the United States.

n CLINICAL TRIALS SUPERVISOR Consumer Product Testing Company, Inc., one of the nation’s largest independent testing facilities, issearching for a clinical trials supervisor.

n ACCOUNT MANAGER/SALES Consumer Product Testing Company, Inc., one of the nation’s largest independent testing facilities, seeksa dynamic sales representative with a minimum two years experience selling in the cosmetic, personal care,pharmaceutical, medical device, or allied industries.

n PERSONAL CARE CHEMIST – MICRO POWDERS Micro Powders Inc., a leading global supplier of wax additives to the personal care and cosmeticsindustries, is seeking a Personal Care Chemist for its Tarrytown, NY location.

n REGULATORY SPECIALIST II – NORTH AMERICA Energizer Personal Care, a consumer goods company operating globally in the broad categories ofhousehold and personal care products, is seeking a Regulatory Specialist.

n COLOR CHEMIST Temptu, a leader in airbrush application and makeup innovations, is seeking a Color Chemist.

n PRINCIPAL SCIENTIST Johnson & Johnson Consumer Products Company, a Division of Johnson & Johnson Consumer Companies,Inc. is hiring a Principal Scientist – Baby Franchise R&D, Global Equity and Americas located in Skillman, NJ.

n FOCAL POINT, PERSONAL CARE & HAIR STYLING SEGMENTS AkzoNobel is a leading global paints and coatings company and a major producer of specialty chemicals,with leading market positions and brands in countries around the world. The BU Surface Chemistry isresponsible for the manufacturing, marketing and distribution of surfactants and polymers for the largestgrowth market segments, Agro, Mining, Oilfield, Fuels & Lubes, Asphalt, Personal Care, and Hair Styling. This position is located in Bridgewater, New Jersey, USA.

n COLOR COSMETIC & PERSONAL CARE BENCH CHEMIST State-of-the-art private label cosmetic and personal care manufacturing company, located in the lowerHudson Valley, NY area, is currently seeking a Chemist/Formulator to join our growing team.

n ACCOUNTS MANAGER – PERSONAL CARE Oleon is a leader in the global oleochemical industry specialized in converting natural fats and oilsinto a wide range of products, such as fatty acids, glycerine, fatty alcohols, esters, and dimers. Our products,made from renewable raw materials, combine high performance with readily biodegradable characteristics.Our products are commonly used in the following applications: lubricants, oilfield, cosmetics, pharmaceuticals,food industry, coatings, and polymers. Location: Virtual Role – covering eastern side of the U.S.

n SENIOR CHEMIST – REGULATORY SPECIALIST IFC Solutions is seeking an experienced, hands-on technical individual to support the color productsand ingredients we custom blend for the food and cosmetic industries.

n SALES POSITION – PROTAMEEN CHEMICALS Protameen, a leader in global specialty chemicals, is searching for someone to fill a Sales Positioncurrently available.

Employment OpportunitiesFor complete ads please go to the NYSCC website:https://nyscc.org/employment/employment-listings/