polymers skin care cosmetics plp olymers in ctic...
TRANSCRIPT
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Polymers Polymers inin
Skin Care CosmeticsSkin Care CosmeticsSkin Care CosmeticsSkin Care Cosmetics
Ampa Jimtaisong, PhD
School of Cosmetic Science
Mae Fah Luang University
Outline
1. Introduction to Elements of Polymer Science
2. Polysaccharide‐Based Polymers
in Cosmetics
3 S th ti P l i C ti3. Synthetic Polymers in Cosmetics
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Elements of Polymer Science
• Polymers are molecules consisting of a large number of identical low molar mass units, named repeat units, that are connected covalentlycovalently.
• If ‐A‐ is the base unit, then a polymer molecule or macromolecule is represented by:
——‐A‐A‐A‐A‐A‐A————or — (A)n—
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Elements of Polymer Science• They are usually classified according to their
use
– thickening agents
fil f– film formers
– resinous powders
– humectants
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Elements of Polymer Science• Natural polymers, gums and resins
– Used in the industry since the early 1940s as water‐soluble binders, thickeners, and film forming agents.
d ’ d h i d d– Today’s products ‐ the growing consumer demand for ‘‘natural products.’’
– Drawbacks of natural polymers • vary in purity & physical appearance
• relatively expensive (compared to common synthetic polymers)
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Elements of Polymer Science• Problems of using natural polymers
– securing stable supplies
– variations in viscosity
– microbial contamination
• Synthetic or semi‐synthetic polymers‐developed to match the properties of gums & resins.
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Elements of Polymer Science
• Natural Polymers or Biopolymers– Proteins and Polypeptides
– Polysaccharides
• Synthetic Polymers
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Elements of Polymer Science
1. Biopolymers‐Proteins and Polypeptides.
• Proteins: the repeat units in proteins are amino acids.
• Amino acids in proteins are linked by an amide linkage between the amino group of one molecule and thebetween the amino group of one molecule and the carboxyl group of another.
• This amide bond is often called peptide bond.
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Elements of Polymer Science
1. Biopolymers‐Proteins and Polypeptides.
• Simple proteins composed only of amino acids‐‐‐>albumin, gelatin, casein, collagen, or keratin.
• Glycoproteins contain amino acid residues andGlycoproteins contain amino acid residues and carbohydrates
• Lipoproteins contain amino acid residues and lipids
• Proteins that possess catalytic activity‐> enzymes.
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Elements of Polymer Science
1. Biopolymers‐ Polysaccharides.
• The repeat units of polysaccharides are simple carbohydrates (sugar units) linked to each other by acetal bonds.
• Among the important polysaccharides are homopolymers of – glucose (starch, glycogen, and cellulose),
– amino‐sugars (chitosan and hyaluronan)
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Elements of Polymer Science
2. Synthetic Polymers
• Considering the application of polymers: (1) plastics
(2) fib(2) fibers
(3) rubbers
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Elements of Polymer Science Definitions and Nomenclature
• Homopolymers are derived from one type of monomer.
• Copolymers require two or more species of monomers.
• Copolymers are distinguished according to the sequence of the various monomer units.
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Elements of Polymer Science Definitions and Nomenclature
Sequence of Monomer Units in Various Copolymers
Copolymer type Schematic composition
• Random
• AlternatingAlternating
• Diblock
• Triblock
• Graft
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PolysaccharidePolysaccharide‐‐Based PolymersBased Polymersin Cosmeticsin Cosmetics
Outline
• INTRODUCTION
• POLYSACCHARIDE STRUCTURE
•• POLYSACCHARIDES FUNCTIONALITYPOLYSACCHARIDES FUNCTIONALITY
– Anionic Polysaccharides
– Cationic Polysaccharides
– Nonionic Polysaccharides
– Amphoteric Polysaccharides
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INTRODUCTION• Polysaccharides perform a myriad of cosmetic functions:– Rheology modifiers
– Suspending agents
– Hair conditionersHair conditioners
– Wound‐healing agents
• They moisturize, hydrate, emulsify, and emolliate.
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INTRODUCTION
• Does a polysaccharide that conditions do so at the expense of its thickening ability?
• How will it behave in the presence of surfactants or salts?
• Does it complex with other components of the formulation?
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POLYSACCHARIDE STRUCTURE
• Polysaccharides are sometimes referred to as ‘‘polyglycans’’ or ‘‘hydrocolloids.’’
• ‘‘Hydrocolloids’’ ‐ for food use.
• Monomers = monosaccharides (‘‘one• Monomers = monosaccharides ( one sugar’’) in polysaccharide chemistry
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Monosaccharides & Polysaccharides
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POLYSACCHARIDE STRUCTUREMonosaccharides & Polysaccharides
Name R1 R2 R3 R4 R5 R6 R7 R8
D-Glucose H OH OH H H OH CH2OH H
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2
D-Glucuronic acid H OH OH H H OH CO2H H
D-Mannose OH H OH H H OH CH2OH H
D-Mannuronic acid OH H OH H H OH CO2H H
D-Galactose H OH OH H OH H CH2OH H
D-Galacturonic acid H OH OH H OH H CO2H H
L-Guluronic acid OH H OH H H OH H CO2H
POLYSACCHARIDES FUNCTIONALITYPOLYSACCHARIDES FUNCTIONALITY
• Anionic Polysaccharides
• Cationic Polysaccharides
• Nonionic Polysaccharides• Nonionic Polysaccharides
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Anionic Polysaccharides
1. Naturally Occurring Anionic Polysaccharides
2. Seminatural Anionic Polysaccharides
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Anionic Polysaccharides
1. Naturally Occurring Anionic Polysaccharidesa. Alginic acid (Alginates).
b. Pectin.
c Carrageenansc. Carrageenans.
d. Xanthan Gum.
e. Hyaluronic Acid and Chondroitin Sulfate.
f. Arabic, Karaya, and Tragacanth Gum.
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Anionic PolysaccharidesAnionic Polysaccharides
a. Alginic acid (Alginates).
• Isolated from marine brown algae and from bacterial fermentation
• Comprised of two different monosaccharides:Comprised of two different monosaccharides:β ‐D‐(1,4)‐mannuronic acid, 4
α ‐L‐(1,4)‐guluronic acid, 5
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Anionic PolysaccharidesAnionic Polysaccharides
a. Alginic acid (Alginates).
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Partial structure of alginic acid showing β-d-(1,4)-mannuronic acid, 4, and α-l-(1,4)-guluronic acid, 5, residues.
Anionic PolysaccharidesAnionic Polysaccharidesa. Alginic acid (Alginates).
28Junction zones formed between alginic acid and Ca2+ ions.
sodium alginate, calcium alginate
Anionic PolysaccharidesAnionic Polysaccharidesa. Alginic acid (Alginates).
• Formulations that employ alginates must control
polyvalent metal ion concentrations through the use
of sequestrants such as q
ethylenediaminetetraacetic acid (EDTA), to optimize
viscosifying effects of the alginate.
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Anionic PolysaccharidesAnionic Polysaccharidesa. Alginic acid (Alginates).
• Most of the anionic polysaccharides are affected to some
degree by fluctuations in pH‐at the higher & lower
extremes.
• Stable at pH 4‐10
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•alginates are not stable at pH<3.0 owing to hydrolysis of the glycosidic bonds holding the polysaccharides together.
Effect of pH on alginate solution viscosity31
•unstable at high pH (above 10)
Anionic Polysaccharides
1. Naturally Occurring Anionic Polysaccharidesa. Alginic acid (Alginates).
b. Pectin.
c Carrageenansc. Carrageenans.
d. Xanthan Gum.
e. Hyaluronic Acid and Chondroitin Sulfate.
f. Arabic, Karaya, and Tragacanth Gum.
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Anionic Polysaccharides
b. Pectin.
• Pectin is isolated by extraction from citrus fruit peels.
• Its structure is similar to that of alginic acid, except pectin is comprised of repeating α‐D‐(1,4)‐pectin is comprised of repeating α D (1,4)galacturonic acid units (6), which are interrupted occasionally by an α‐L‐(1,2)‐rhamanose (7)
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Anionic Polysaccharides
b. Pectin.
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Partial structure of pectin showing a-d-(1,4)-galacturonic acid, 6, and a-l-rhamanose,7.
Partially nonionic
Anionic Polysaccharidesb. Pectin.
• Pectin is sold in grades designated by methyl ester level.
• Lower levels of ester groups make the pectin more anionic.
• Pectin behaves much like alginic acid when its methyl ester
l l b l 50% i f bid l i h flevels are below 50%; it forms turbid gels in the presence of
divalent metal ions, calcium in particular.
• At highmethyl ester levels, it can form gels without divalent ion,
but the concentration of polysaccharide required is typically
much higher.
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Anionic Polysaccharides
b. Pectin.
• Pectin is well suited for low‐pH applications considering its
source (functions ideally at pHs near 3.5)
• Below this pH, it suffers from hydrolysis and in highly alkalineBelow this pH, it suffers from hydrolysis and in highly alkaline
solutions, hydrolysis of the ester is rapid.
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Anionic Polysaccharides
1. Naturally Occurring Anionic Polysaccharidesa. Alginic acid (Alginates).
b. Pectin.
c Carrageenansc. Carrageenans.
d. Xanthan Gum.
e. Hyaluronic Acid and Chondroitin Sulfate.
f. Arabic, Karaya, and Tragacanth Gum.
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Anionic Polysaccharidesc. Carrageenans.
• The carrageenans are isolated from marine red algae.
• At least seven varieties of carrageenans are known, differentiated by Greek letters.
Th f t t i l i t t• The carrageenans of greatest commercial interest are primarily comprised of two repeating monosaccharides : β‐D‐(1,3)‐galactose (8) and α‐D‐(1,4)‐galactose (9).
• The most commercially accessible varieties include kappa (k)‐, iota (i)‐, and lambda (λ)‐carrageenan.
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Anionic Polysaccharidesc. Carrageenans.
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Carrageenan type R1 R2 R3 R4 R5Kappa (strong, rigid gels) OH OSO3
- O OH CH2
Iota (soft gels) OH OSO3- O OSO3
- CH2
Lambda OSO3- OH OH OSO3
- CH2OSO3-
Anionic, highly acidic, hydrophilic
Anionic Polysaccharidesc. Carrageenans.
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Anionic Polysaccharides
1. Naturally Occurring Anionic Polysaccharidesa. Alginic acid (Alginates).
b. Pectin.
c Carrageenansc. Carrageenans.
d. Xanthan Gum.
e. Hyaluronic Acid and Chondroitin Sulfate.
f. Arabic, Karaya, and Tragacanth Gum.
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Anionic Polysaccharides
d. Xanthan Gum.
• Bacterial fermentation
• Show remarkable viscosity stability at increasing temperatures ‐ Stable at pH 1‐12, Stable to heat
• Xanthan gum solutions are pseudoplastic.
• Xanthan gum is incompatible with most cationic surfactants.
• Xanthan’s thickening efficiency is synergistically enhanced by the addition of colloidal magnesium aluminum silicate (Veegum).
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Anionic Polysaccharides
Partial structure of xanthan gum showing β-d-
d. Xanthan Gum.
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g g β(1,4)-glucose, 10, acetylated β-d-(1,2)-mannose, 11, β-d-(1,4)-glucuronic acid, 12, and pyruvic acid terminated β-d-mannose,13.
Anionic Polysaccharides
1. Naturally Occurring Anionic Polysaccharidesa. Alginic acid (Alginates).
b. Pectin.
c Carrageenansc. Carrageenans.
d. Xanthan Gum.
e. Hyaluronic Acid and Chondroitin Sulfate.
f. Arabic, Karaya, and Tragacanth Gum.
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Anionic Polysaccharidese. Hyaluronic Acid and Chondroitin Sulfate.
• Hyaluronic acid and chondroitin sulfate are isolated from various animal tissues.
• Cosmetic Hyaluronic acid is also commercially manufactured b b t i l f t tiby bacterial fermentation.
• Hyaluronic acid – occur in the dermis of the skin
– being cellular turgidity (because of its water‐binding capacity) and lubrication.
– play a key role in wound healing.
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Anionic Polysaccharidese. Hyaluronic Acid and Chondroitin Sulfate.
• Hyaluronic acid and chondroitin sulfate are covalently
bound with various proteins in the animal tissue ‐
‘‘proteoglycans.’’
• The unique acetylated‐amine‐containing monosaccharide
classified these polysaccharides as glucosaminoglycans
(amino‐containing sugars).
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Anionic Polysaccharidese. Hyaluronic Acid and Chondroitin Sulfate.
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Polysaccharide R1 R2Hyaluronic acid H HChondroitin-4-sulfate SO3
- HChondroitin-6-sulfate H SO3
-
comprised of two repeating units: β-D-(1,4)-glucuronic acid (14) N-acetyl-β-d-(1,3)-glucosamine (15)
Anionic Polysaccharides
1. Naturally Occurring Anionic Polysaccharidesa. Alginic acid (Alginates).
b. Pectin.
c Carrageenansc. Carrageenans.
d. Xanthan Gum.
e. Hyaluronic Acid and Chondroitin Sulfate.
f. Arabic, Karaya, and Tragacanth Gum.
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Anionic Polysaccharides
f. Arabic, Karaya, and Tragacanth Gum.
• The exudates gums are isolated from the sap of specific trees and bushes that use each particular sap for protection, fluid transport, and energy storage.
• All of the gum exudates are nontoxic and are generally• All of the gum exudates are nontoxic and are generally recognized as safe for use in cosmetics.
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Anionic PolysaccharidesAnionic Polysaccharidesf. Arabic, Karaya, and Tragacanth Gum.
• Arabic gum (Acacia)
relatively low molecular weight‐ high levels solids ‐ without
significant viscosity buildup.
dissolves in water at > 50 wt% solids ‐ flowable.
its maximum viscosifying effect near pH 6.0
the viscosity drops quickly ‐ pH becomes higher or lower.
Multivalent cations reduce the viscosity of solutions of arabic
gum, but the gum will not precipitate
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Anionic PolysaccharidesAnionic Polysaccharidesf. Arabic, Karaya, and Tragacanth Gum.
• Gum karaya
gum karaya swells in water and develops significant viscosity even at low concentration.
stickiness accompanies the swelling‐denture adhesives.
performs best at pH values between 7 and 9
the viscosity depends on the order of hydration and pH adjustment.
if it is hydrated first ‐ then the solution pH raised, the viscosity is higher than if dried polysaccharide is added directly to an alkaline solution.
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Anionic PolysaccharidesAnionic Polysaccharidesf. Arabic, Karaya, and Tragacanth Gum.
• Gum tragacanth
shares many of the functional properties found in xanthan gum.
At low concentrations it produces high solution viscosities.
Tragacanth has high pH stabilityTragacanth has high pH stability
its viscosity‐ thins as the temperature increases.
Tragacanth strongly binds multivalent cations: including calcium, precipitate the polysaccharide from solution.
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Anionic Polysaccharides
1. Naturally Occurring Anionic Polysaccharides
2. Seminatural Anionic Polysaccharidesa. Cellulose Gum (Sodium Carboxymethylcellulose)
b C b h l hi ib. Carboxymethylchitin
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Anionic PolysaccharidesAnionic Polysaccharides
a. Cellulose Gum or Sodium Carboxymethylcellulose (CMC)
CMC is a chemically altered derivative of cellulose.
Cellulose is a naturally occurring, structural polysaccharide found in all plants.
Cellulose is composed of one repeating monosaccharide, β‐d‐Cellulose is composed of one repeating monosaccharide, β d(1,4)‐glucose (16)
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Partial structure and synthesis of cellulose gum, 18, showing repeating b‐d‐(1,4)‐glucose,16, in cellulose backbone.
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Anionic Polysaccharidesa. Cellulose Gum or Sodium Carboxymethylcellulose (CMC)
• pH >4.5, CMC is in the salt form‐water soluble.
• pH <4.5, CMC water‐insoluble.
– The insolubility appears first as an increase in viscosity and phase
separation occurs.
– Eventually, as the CMC continues to phase separate, the solution
becomes hazy and precipitation occurs.
• CMC also dissolves in and thickens glycerin solutions (small
amount of H2O added).
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Anionic Polysaccharidesa. Cellulose Gum or Sodium Carboxymethylcellulose (CMC)• CMC forms association complexes with strongly anionic
surfactants– addition of sodium dodecyl sulfate to a solution of dissolved CMC
forms gels.
• Cationic surfactants have strong ionic interaction with CMC‐neutralize the charge of CMC
– At the point of charge neutralization, phase separation occurs.
• Stable at pH 4‐10
• Sensitive to heat, electrolytes
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Anionic Polysaccharides
1. Naturally Occurring Anionic Polysaccharides
2. Seminatural Anionic Polysaccharidesa. Cellulose Gum (Sodium Carboxymethylcellulose).
b. Carboxymethylchitin.
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Anionic PolysaccharidesAnionic Polysaccharidesb. Carboxymethylchitin.
• Carboxymethylchitin (CMCh), in Japan ‐ ‘‘chitin liquid’’.
• It is manufactured by the carboxymethylation of chitinchitin
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Anionic Polysaccharidesb. Carboxymethylchitin.
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POLYSACCHARIDES FUNCTIONALITYPOLYSACCHARIDES FUNCTIONALITY
• Anionic Polysaccharides
• Cationic Polysaccharides
• Nonionic Polysaccharides• Nonionic Polysaccharides
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Cationic PolysaccharidesCationic Polysaccharides
1. Naturally Occurring Cationic Polysaccharidesa. Chitosan.
2. Seminatural Cationic PolysaccharidesC ti i H d th l ll la. Cationic Hydroxyethylcellulose
• Cationic HEC, 27, more commonly known by its INCI name,
polyquaternium‐10, is used as a conditioner delivered from
shampoos & conditioners.
• The cationic HEC, 28 ( polyquaternium‐4) is found as a conditioning
& fixative adjuvant in hair fixatives.
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Cationic Polysaccharides
Chitosan
• It is not cationic or water‐soluble unless the pH < 7.0
• It is neutralized at these low pH values to the water‐soluble
chitosonium salt (22).
C i ll th l h id i ft f d t li d• Commercially, the polysaccharide is often found neutralized
with a cosmetically functional carboxylic acid such as lactic
acid or glycolic acid, α‐hydroxy acids,
• Chitosan, employed as its salt, has strong substantivity to
anionic surfaces like skin and hair.
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chitosan
chitin
65Formation of chitosan, 21, and chitosan salts, 22, from native chitin, 19.
Chitosan salts
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Cationic Polysaccharides
Chitosan
• It is a film‐forming polysaccharide that has been used
in fixative formulations and 2‐in‐1 shampoos.
• Chitosan forms strong water‐insoluble associativeChitosan forms strong water insoluble associative complexes with most anionic surfactants.
• Evidence suggests that chitosan aids in the healing of
wounds and damaged skin.
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The chitosan bandageBattlefield Band‐Aids
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ChitoGauze TM The Hemostatic HemCon® Bandage
POLYSACCHARIDES FUNCTIONALITYPOLYSACCHARIDES FUNCTIONALITY
• Anionic Polysaccharides
• Cationic Polysaccharides
• Nonionic Polysaccharides• Nonionic Polysaccharides
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Nonionic Polysaccharides
1. Naturally Occurring Nonionic Polysaccharidesa. Starch.
b. Cyclodextrins.
2 S i t l N i i P l h id2. Seminatural Nonionic Polysaccharidesa. The Cellulose Ethers (5 sub types)
b. Nitrocellulose
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Nonionic PolysaccharidesNonionic Polysaccharides
a. Starch.
• Starch is an energy‐storage polyglycan
• Corn, potato, rice, wheat, and tapioca
• It is composed of amylopectin and amylose
• Starch is an inexpensive nontoxic polyglycan used• Starch is an inexpensive, nontoxic polyglycan used
primarily as a rheology modifier.
• The thickening effects of starch range from water‐thin
viscosity to that of a gummy gel.
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amylopectin
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amylose
The higher the ratio of amylose to amylopectin, the greater the thickening effect.
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Nonionic Polysaccharidesb. Cyclodextrins
• Cyclodextrins are used extensively in cosmetic and drug delivery applications.
• The interior portion of the cyclodextrin is a lipophilic (‘‘oil‐loving’’) environmentloving ) environment.
• If the lipophilic materials are water‐insoluble, their complex with a cyclodextrin may render them more water‐soluble.
• The exterior of the cyclodextrin is hydrophilic‐ water‐solublecyclodextrins.
73 74Cyclodextrin
Nonionic Polysaccharides
1. Naturally Occurring Nonionic Polysaccharidesa. Starch.
b. Cyclodextrins.
2 S i t l N i i P l h id2. Seminatural Nonionic Polysaccharidesa. The Cellulose Ethers (5 sub types)
b. Nitrocellulose
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Nonionic PolysaccharidesNonionic Polysaccharidesa. The Cellulose Ethers
• The most popular and useful rheology control materials employed in the personal care industry.
• History of safe and effective use.
• The available cellulose ethers are generated from basic cellulose pulp and can be grouped, loosely, into a family tree.
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Nonionic PolysaccharidesNonionic Polysaccharides
a. The Cellulose Ethers
• Starting from cellulose, It can be treated with
– ethylene oxide to give hydroxyethylcellulose (HEC)
– propyleneoxide to give hydroxypropylcellulose (HPC)
– methyl chloride to give methylcellulose (MC)
• HEC can be treated with an activated ethylating agent to make
ethylhydroxyethylcellulose (EHEC)
• HPC can be further treated with methyl chloride to afford
hydroxypropylmethylcellulose (HPMC)
77Handout
Nonionic PolysaccharidesNonionic Polysaccharides
a. The Cellulose Ethers
• Generally all of the cellulose ethers dissolve in water at room temperature and ambient pressure.
• Salts increase the solvent polarity, which reduces the solubility of more lipophilic cellulose ethers such as HPCsolubility of more lipophilic cellulose ethers such as HPC and HPMC.
• Surfactants can increase the solubility or viscosity of slightly surface‐active cellulose ethers, such as HPC and HPMC.
• The effects, difficult to predict, are best evaluated experimentally.
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Nonionic Polysaccharidesa. The Cellulose Ethers
• The solubility of most cellulose ethers decreases as their
solution temperature increases.
• As the temperature continues to increase, finally the p , y
polysaccharide collapses upon itself and precipitates from
solution.
• The temperature at which a cellulose ether falls out of
solution is characteristic of that ether and is known as the
cloud point (cp)
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Nonionic PolysaccharidesNonionic Polysaccharides
a. The Cellulose Ethers i. Hydroxyethylcellulose.
ii. Hydroxypropylcellulose
iii Methylcelluloseiii. Methylcellulose
iv. Hydroxypropylmethylcellulose
v. Ethylhydroxyethylcellulose
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Nonionic Polysaccharidesi. Hydroxyethylcellulose (HEC).
• HEC is unique among the cellulose ethers for its lack of a cp
• HEC is the most hydrophilic and most widely used cellulose ether.
• It is not soluble in many cosmetically practical organic solvents including the hydroalcoholic solvents.
• HEC is more tolerant to extremes of pH, salts, and surfactants than the other cellulose ethers.
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Nonionic Polysaccharides
ii. Hydroxypropylcellulose (HPC)– HPC has its cp at about 45°C.
– Above this temperature, it will not hydrate when added to water; if already dissolved, it will fall out of solution upon heating to 45°C.
– Hydration of the polysaccharide is best done by adding it to hot water, where it fully disperses, and upon cooling completely dissolves without clumping.
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Nonionic PolysaccharidesNonionic Polysaccharides
ii. Hydroxypropylcellulose (HPC)
• Because of the pendent methyl groups on the propylene
oxide side chains, HPC is much more lipophilic than HEC.
• This allows HPC to dissolve in and thicken many organic
systems such as ethyl alcohol, aqueous ethyl alcohol, and
propylene glycol.
• HPC is tolerant to fluctuation of pH
• Surfactant and salts have influence on aqueous HPC
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Nonionic Polysaccharidesiii. Methylcellulose (MC)
• MC has a gel point near 45°C .
• Above 56°C MC precipitates as a hazy cloud.
• MC shares many of the same solution attributes of HPC’s
chemistry, but tends to be more lipophilic than HPC.
• This enables it to dissolve and thicken a broader range of
nonaqueous solvents including ethylene and propylene
glycol, glycerin, and some oils.
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Nonionic PolysaccharidesNonionic Polysaccharidesiv. Hydroxypropylmethylcellulose (HPMC)
• Hydroxypropylmethylcellulose shares characteristic solution properties of both HPC and MC.
• Because of its inherent lipophilicity and surface activity HPMC maintains stable oil‐in‐water emulsions even after heat sterilization.
• This provides unique opportunities to prepare sterile creams and lotions for pharmaceutical and dermatological applications.
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Nonionic Polysaccharides
1. Naturally Occurring Nonionic Polysaccharidesa. Starch.
b. Maltodextrins/Cyclodextrins.
2 S i t l N i i P l h id2. Seminatural Nonionic Polysaccharidesa. The Cellulose Ethers (5 sub types)
b. Nitrocellulose
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Nonionic PolysaccharidesNonionic Polysaccharidesb. Nitrocellulose
• Nitrocellulose is one of the oldest‐known modified cellulose derivatives.
• It is manufactured by treating cellulose pulp with a combination of nitric and sulfuric acids.
• Levels of commercial nitration are extremely critical because ycellulose, nitrated to levels greater than 12% nitrogen‐ an explosive.
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Protein‐Based Polymers
I. Animal Sources
a) Collagen
b) Elastin
c) Keratin
d) Milk Protein
II. Vegetable Sourcesa) Wheat Glutenb) Soy Proteind) Milk Protein
e) Silk Protein derivatives
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b) Soy Proteinc) Corn (Protein Isolate)d) Caseine) Yeast Protein
Synthetic Polymers in Cosmetics Synthetic Polymers in Cosmetics
Outline
Thickening Polymers
• Carbomers
• Polyvinyl pyrrolidone
• Polyvinylpyrrolidone‐vinyl acetate
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Synthetic Polymers
Carbomer
Known as Carbopols, carboxypolymethylene, carboxyvinyl polymer or acrylic acid polymer
It dispersed in water to form an acidic colloidal solution of low viscosity, which produces a high viscous gel on neutralization with inorganic or organic bases like sodium hydroxide, triethanolamine, etc.
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Synthetic PolymersCarbomer
Carbomer gels are most viscous between pH 6 and 11.
The viscosity is reduced on lowering the pH to below 3 or rising above 12.
Electrolytes also reduce the viscosity of carbopol dispersionsElectrolytes also reduce the viscosity of carbopol dispersions.
Carbomer is susceptible to oxidation especially on exposure to light and hence formulations should be stabilized by addition of appropriate antioxidants and chelating agents.
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Synthetic Polymers
Carbomer
Several viscosity grades are available and the usual concentration used varies from 0.1% to 4% as
disuspending agent.
Carbomer 934
Carbomer 940
Carbomer 941
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Synthetic Polymers
Polyvinylpyrrolidone (PVP)It can dissolve in water and a variety of organic solvent.
It has good hygroscopicity, film‐forming capability, complexing ability and physiology compatibility
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Synthetic Polymers
Polyvinylpyrrolidone (PVP)Cosmetics: PVP‐K series can be used as film‐forming agent, viscosity‐enhancement agent, lubricator and adhesivelubricator and adhesive.
PVP‐K30, PVP‐K85, PVP‐K90
They are the key component of hair sprays, mousse, gels and lotions & solution, hair‐dying reagent and shampoo in hair‐care products.
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Synthetic Polymers
Polyvinylpyrrolidone‐vinyl acetate
copolymer (PVP/VA)PVP/VA forms hard, glossy, water‐removable films.
Its viscosity softening point and water sensitivityIts viscosity, softening point and water sensitivity vary with PVP/VA ratio.
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Reference
• E. Desmond Goddard, James V. Gruber, Principles of Polymer Science and Technology in Cosmetics and Personal Care (Cosmetic science and technology : v. 22), MARCEL DEKKER, INC, New York, NY, USA. 1999.
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