Today’s consumers are increasingly discerning and demanding when it comes to the products they’ll use to create hairstyles that look good, last long and feel great. The development of hair styling products that meet performance and cost requirements is further complicated by the consumers’ desire for products that contain naturally derived or sustainable ingredients.

To meet these requirements, formulators must move beyond the traditional portfolio of synthetic polymers that have long been employed as the hair fixative ingredients in gels, mousses and styling aids. AkzoNobel Personal Care has developed a new hair fixative polymer that features an improved sustainability profile compared to traditional styling polymers, such as PVP (polyvinylpyrrolidone) and VP/VA (vinyl pyrrolidone/vinyl acetate) copolymers. Innovation in natural polymer modification has enabled the development of this new polymer, which can be used to create styling products with a more sustainable and renewable ingredient profile while still maintaining the formulation attributes and performance characteristics desired by the consumer.

Styling Gel Basics
Hair styling gels and related styling products are designed to help create unique styles and hold the style in place. A well-formulated gel will remain flexible when initially applied to the hair but will become stiff as it dries. The primary ingredient that makes a styling gel hold the hair in place is the fixative polymer. These polymers are typically based on synthetic vinyl monomers such as PVP or VP/VA copolymer. They give good hold while remaining sufficiently hydrophilic to be easily washed out of the hair. The other ingredient that is critical in a styling gel is the rheology modifier. There are countless cosmetically-acceptable rheology modifiers or thickening agents that can be used for styling applications. The most common styling gel rheology modifier is carbomer, a synthetic acrylic polymer that is acidic when put into a water solution. When the polymer is neutralized with a base such as triethanolamine, it causes crosslinking within the polymer, which in turn creates the distinctive gel rheology and texture that is popular with today’s consumer.

Other ingredients, including colorants, solubilizers, solvents, emollients, spreading agents, preservatives and conditioning agents, have varying degrees of effect on the overall performance of the styling product. But the fixative polymer and the rheology modifier are the main determinants of the overall attributes of a hair gel.

A common gel format is PVP and carbomer. This gel system, while well known and widely used, is also completely synthetic in nature. As today’s formulators get pressured to develop and introduce products with a more sustainable and renewable profile, the need for alternative gel ingredients has become more pronounced. The introduction of Maltodextrin/VP copolymer* allows the formulator to make cutting-edge styling formulations with a more naturally derived product profile. Gels formulated with Maltodextrin/VP copolymer feature equivalent fixative polymer performance as compared to gels based on market-leading synthetic polymers, thereby allowing the development of more naturally derived gels and styling products without compromise on performance or product aesthetic properties.

Chemistry and Properties
Consumer interest in naturally derived styling products continues to grow, but efficacy remains paramount. Consumers want more natural products that strike the right balance of performance and value. By utilizing the naturally derived oligosaccharide maltodextrin as a starting material, scientists at AkzoNobel Personal Care have created a styling polymer that features a more renewable profile versus traditional PVP or VP/VA copolymers.

This unique polymer is produced via polymerization of n-vinyl pyrrolidone in the presence of maltodextrin. This new hybrid technology has been assigned the INCI name Maltodextrin/VP copolymer. The polymer is nonionic, supplied as a 25% solids solution in water, and contains a globally accepted preservative. The proposed structure of Maltodextrin/VP copolymer is shown in Figure 1.

Figure 1. Proposed chemical structure of Maltodextrin/VP copolymer

When incorporated into hair styling formulations, Maltodextrin/VP copolymer provides exceptional clarity and consumer-preferred rheology. These features are typically associated with synthetic fixative polymers, and to date have not been achievable with more naturally derived starting materials. Maltodextrin/VP copolymer contains more than 50% naturally derived content, resulting in an improved sustainability profile compared with traditional synthetic nonionic fixative polymers. Maltodextrin/VP copolymer is the first more sustainable hair fixative polymer in the marketplace to provide excellent clarity, carbomer compatibility and desirable on-hair performance.

Performance Summary
Maltodextrin/VP copolymer provides the benefits that meet today’s formulating needs by offering styling performance similar to that achieved with well-known and widely used polymers such as PVP (having a K value of 30) and VP/VA copolymer. Hair styling gels formulated with Maltodextrin/VP copolymer were compared to PVP (having a K value of 30) and VP/VA copolymer gels. Results show that Maltodextrin/VP copolymer has:

• Overall performance equivalent to that of PVP (with a K value of 30) or VP/VA copolymer for wide formulating latitude and broad range of application. Maltodextrin/VP copolymer can readily be incorporated into existing product formulations through a 1:1 exchange of the traditional styling polymer.
• Excellent compatibility with polyacrylic acid thickeners such as carbomer, which helps produce clear gels with consumer-preferred rheology.
• Low solution turbidity, which creates exceptional clarity in clear gel applications (when used with carbomer).
• Low product viscosity for ease of handling and use.
• Alcohol tolerance up to 15%, enabling a broad range of use in various styling applications and across many regions.
• No solvents, allowing for use in low and zero VOC systems.
• Excellent compatibility with commonly used gel ingredients.
• No need for polymer neutralization, streamlining formulations and reducing costs.
• Cost-effective performance in styling formulations.

Gel Formulation Properties
Maltodextrin/VP copolymer provides the formulator with a new option to satisfy customer and consumer demands for more natural styling products without any compromise on performance. Maltodextrin/VP copolymer can be used in a wide range of products such as gels, mousses, lotions, creams, pomades, spritzes and other styling aids. Recommended Maltodextrin/VP copolymer use levels range from 4-25% (as supplied) in hair gels, 8-24% (as supplied) in mousses and 4-24% (as supplied) in styling creams and lotions.

Maltodextrin/VP copolymer features excellent gel clarity, stability and aesthetic properties. As shown in Table 1, when gels containing carbomer rheology modifier are neutralized with aminomethylpropanol (AMP) or triethanolamine (TEA), the Maltodextrin/VP copolymer gel shows a slightly higher viscosity (at equal polymer use levels) compared to gels formulated with PVP or VP/VA copolymer.

The Maltodextrin/VP copolymer gels feature very low turbidity and clarity similar to gels based on traditional, synthetic-based polymers. Earlier styling polymers that were more naturally derived were typically cloudy to opaque when incorporated into gel systems. This high turbidity, along with unusual rheological properties, resulted in limited consumer acceptance in styling products.

On-Hair Performance
On-hair performance testing was performed on a simple hair styling gel containing 3% active polymer and 0.5% carbomer. A gel formulated with the Maltodextrin/VP copolymer was compared to a gel containing PVP (having a K value of 30) and also to a gel containing VP/VA copolymer. An eight-person trained panel evaluated for subjective properties of gloss, stiffness, dry comb, flaking, static and dry feel. All testing was done on European virgin brown hair tresses. The results are reported at a 95% confidence level.

As shown in Table 2, the hair gel formulated with Maltodextrin/VP copolymer had superior dry feel compared to the PVP gel-treated hair tress. No detectable differences in on-hair performance properties were seen when comparing hair tresses treated with the Maltodextrin/VP copolymer gel to tresses treated with VP/VA copolymer gel.

Formulators can easily and confidently substitute Maltodextrin/VP copolymer for the commonly used synthetic nonionic polymers at equal active polymer levels. The test results indicate very little difference in on-hair properties between the Maltodextrin/VP copolymer and the synthetic nonionic polymers.

High Humidity Curl Retention
High-humidity curl retention is a well-accepted indicator of the humidity resistance of a product and is used as a gauge for overall hold. In high-humidity curl retention evaluations, virgin brown European hair tresses are treated with the gels, rolled in curlers and allowed to dry in a constant temperature and humidity room. These tresses are then subjected to 21°C, 90% relative humidity conditions and the rate that the curl “falls out” of the tress is measured.

As shown in Figure 2, Maltodextrin/VP copolymer has similar humidity resistance (at the 95% confidence level) to PVP and VP/VA copolymer after two hours.

Figure 2. High humidity curl retention using a basic hair gel formulation indicates Maltodextrin/VP copolymer performs similarly to commonly used synthetic nonionic polymers at the 95% confidence level.

Compatibility and Uses
Maltodextrin/VP copolymer is supplied as a low-viscosity aqueous solution, making it easy to incorporate into a variety of styling products. It is nonionic and has excellent compatibility with other commonly used personal care ingredients. Maltodextrin/VP copolymer is soluble in water as well as hydroalcoholic solutions, tolerating up to 15% ethanol. In addition, it is compatible with most common gel additives, including, but not limited to, panthenol, silicones, sorbitol, EDTA, GLDA, polyethylene glycols and polypropylene glycols.

Good gel clarity and viscosity are achieved in conjunction with carbomer. Maltodextrin/VP copolymer is also compatible with other rheology modifiers, including ethyl hydroxyethylcellulose, hydroxyethylcellulose, acrylates/steareth-20 itaconate copolymer and acrylates/C10-30 alkyl acrylate crosspolymer. It is compatible with many other nonionic, anionic or cationic polymers, which permits its use where different performance characteristics or product formats may be desired.

Formulation Suggestions
When using Maltodextrin/VP copolymer with carbomer, Maltodextrin/VP should be added to the batch after the carbomer has been neutralized. For optimal clarity in carbomer gels, the formulation pH should be adjusted with the selected base to a pH of 6.0-6.5.

Improved Sustainability
Cradle-to-grave life cycle analysis of hair gels containing different styling polymers was also conducted.The styling polymers included Maltodextrin/VP copolymer and PVP.Primary energy use, material resource use, emissions to air, emissions to water, and land use were the factors considered for the analysis. Experimental evidence and literature published data were used to assign values to these factors. Environmental impact of the different cases was assessed using four different weighting scenarios based on current best practices in life cycle analysis (LCA).

Hair gels based solely on PVP have the highest environmental impact.Replacing PVP with Maltodextrin/VP copolymer significantly reduces the environmental impact in all four different weighting scenarios.The cradle-to-grave life cycle analysis serves to verify and validate the claims of improved sustainability that can be associated with the use of the Maltodextrin/VP copolymer in styling products.

Conclusions
A new hybrid polymer of maltodextrin and vinyl pyrrolidone enables the optimization of styling product formulation performance, properties and economics while simultaneously providing a more naturally-derived product composition. This new polymer allows the formulator to make styling aids that are more naturally derived and renewable without any compromise on cost, gel clarity, product aesthetics or on-hair performance.

This robust polymer is easy to use, has broad ingredient compatibility, and wide formulation latitude to allow for the creation of a variety of high-performance hair styling products, including styling gels, spray gels, mousses, creams, waxes and pomades with a more sustainable profile.

*Marketed by AkzoNobel Personal Care as Biostyle CGP Polymer

Styling Product Formulations Containing Maltodextrin/VP CopolymerSustainable Styling Gel (2422-27.B)

Ingredients:	%Wt.
Deionized water (aqua)	65.98
Disodium EDTA	0.02
Panthenol	0.15
Triethanolamine	0.40
Maltodextrin/VP copolymer	12.50
Carbomer (2.0% aqueous solution)	20.00
PEG-12 dimethicone	0.20
Phenoxyethanol (and) ethylhexylglycerin	0.75

PROCEDURE: Charge all the water contained in the formula into the main mixing vessel and mix at 600 rpm using a 4 leaf propeller blade. Add the disodium EDTA and continue mixing until dissolved. Add the panthenol and continue mixing until dissolved. Add approximately half of the TEA to the main mixing vessel and continue mixing. Add the Maltodextrin/VP copolymer and mix until homogeneous. Slowly sift the 2% carbomer solution into the center of the vortex. Allow to mix until completely dispersed and smooth. Switch mixing to a U blade and mix at 100rpm. Add the silicone and continue mixing. Add TEA until a pH between 5.75 and 6.25 is reached. Add the preservative and continue mixing until homogeneous. PROPERTIES: Appearance: clear gel; pH: 5.5-6.5; Viscosity: 30000-35000, Heliopath T-C spindle, 10 rpm @ 25ºC

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Novel Product Forms and TexturesMale Fundamentals Fiber Wax (2431-46)

Ingredients:	%Wt.
Phase A
Deionized water (aqua)	48.50
Maltodextrin/VP copolymer	8.00
Hydroxypropyl starch phosphate	4.00
Phase B
Lanolin wax	12.00
Cetearyl alcohol	9.00
Tridecyl stearate (and) tridecyl trimellilate(and) dipentaerythrityl hexacaprylate/hexacaprate	4.00
Ceteareth-25	5.00
PEG-8 beeswax	8.00
Phase C
Phenoxyethanol (and) methylparaben (and)ethylparaben (and) butylparaben(and) propylparaben (and) isobutylparaben	1.50

PROCEDURE:Charge all the water contained in the formulation into the main mixing vessel and begin mixing with propeller agitation. The speed of the agitation should be adjusted to pull a vortex 2/3 of the way down the mixing shaft. Add the Maltodextrin/VP copolymer into the main mixing vessel and allow to mix until homogeneous. Slowly sift in the hydroxypropyl starch phosphate. Begin heating the main vessel to 80°C and hold at 80°C. Into a second vessel add all the ingredients in phase B. Place this vessel in a hot water bath and melt all the ingredients together. Once all the ingredients in phase B have been melted together and phase A has reached 80°C, add phase B to phase A.

Both phases will be hot. It is important to maintain good mixing during the addition and adjustment up in mixing speed will be required (try to maintain the vortex 2/3 of the way down the mixing shaft). Do not incorporate air into the formula as this will alter the texture of the wax. Once phase B has been incorporated into phase A and the mixture is homogeneous, begin cooling. Once the main phase has reached 70°C, add the preservative and mix well. This product is a hot fill and should be poured off before it reaches 65°C. Caution: Do not cap containers until the product has reached room temperature. Failure to wait will result in condensation that could form a mold layer on the top of the product.

PROPERTIES: Appearance: hard, low shine wax.

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Styling Jello (2510-9)

Ingredients:	%WT
Phase A
Water (aqua)	80.84
Panthenol	0.15
Acrylates/steareth-20 itaconatecopolymer (and) water (29% active)	5.17
Maltodextrin/VP copolymer	12.44
Triethanolamine	0.70
PEG-12 dimethicone	0.20
DMDM hydantoin (and) iodopropynyl butylcarbamate	0.50

PROCEDURE: Charge all the water contained in the formula into the main mixing vessel and begin mixing at 450 rpm using a 4 leaf propeller blade. Slowly sift the panthenol into the main mixing vessel and continue mixing until dissolved. Add the acrylates/steareth-20 itaconate copolymer into the vortex and mix until homogeneous. Add TEA until a pH of approximately 5.9 is reached and continue mixing. Add the Maltodextrin/VP copolymer and increase mixing speed to 650 rpm. Mix until uniform. Switch mixing to a U blade and mix at 100 rpm. Add the remaining ingredients, mixing well between each addition. Add TEA to adjust the pH to 6.5-7.0. Add the preservative and continue mixing until homogeneous.

PROPERTIES: pH: 6.5-7.0; Appearance: clear gel; Viscosity: 53,000-63,000 cps (Heliopath T-C spindle,10 rpm @ 25°C).


Sustainable Sea Salt Texturizing Spritz (2431-56)

Ingredients:	%WT
Phase A
Water	81.18
Maltodextrin/VP copolymer	16.67
Propylene Glycol	0.10
Panthenol	0.15
PEG-12 Dimethicone	0.20
RS Sea Salt	1.00
Phenoxyethanol (and) ethylhexylglycerin	0.70

PROCEDURE: Charge all the water contained in Phase A into the main mixing vessel and mix at 600 rpm using a 4 leaf propeller blade. Add Maltodextrin/VP Copolymer and mix until homogeneous. Add the remaining ingredients mixing well between each addition.

PROPERTIES: pH 6.5 - 7.0; Appearance: clear, water-white liquid;

PACKAGING: Aptar; Product—Cardinal Optima 24mm Labnum Card Spray .014 X .010 Deep; Button— Cardinal Spray White WPC-116; Insert—014 S 010 DP Chan Natural; Body—140 MCL Output EM Optima Orange; Piston—EM II Piston; Poppet—EM II Poppet; Turret—24MM; Liner—EM 24 MM Dark Blue; Spring—Stainless Steel EM Optima; Seal Valve—EM II Seal Valve; Tube—.060 Capillary; Tube Length—06 13/16”




Natural Volumizing Mousse (2422-27.C)

Ingredients:	%WT
Concentrate Phase
Water	84.67
Polyquaternium-4	0.10
Maltodextrin/VP copolymer	8.33
Polysorbate 20	0.40
DMDM Hydantoin (and) iodopropynyl butylcarbamate	0.50
Propellant Phase
Isobutane (and) propane	6.00

PROCEDURE: Charge all the water contained in the formula into the main mixing vessel and mix at 600rpm using a 4 leaf propeller blade. Slowly sift the polyquaternium-4 into the main mixing vessel and continue mixing until completely hydrated. Add the maltodextrin/VP copolymer and mix until homogeneous. Add the remaining ingredients one at a time, mixing well between each addition. Continue mixing until homogeneous. Charge cans with “Can Fill” amount of concentrate and propellant.

PROPERTIES: pH: 6.25-6.75; Appearance: white mousse; Foam density: 0.05 g/ml.


PACKAGING: Valve type—Aptar VX-81; Body Orifice—VX No orifice 2 X 0.030 VT; Stem Orifice— VX80 0.343 FC 0.018 Orifice; Gasket—VX 0.045 Buna P Code 150; Spring—VX Stainless steel 0.018 Open C; Cup—AL Avon 106 pH free EPTB D









The authors recognize the contributions of those who worked on the development of Maltodextrin/VP copolymer including Anthony Adamo, Michael T. Philbin, Ph.D, Crystal Priester, Norman Rackison, John Thomaides, Melissa Vitale and others in AkzoNobel Personal Care.

More info: Laurie J. Marshall, global marketing manager, styling, Tel: 908-707-3606; Email: laurie.marshall@akzonobel.com