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Outline
Polymers 1. Introduction to Elements of Polymer Science
2. Polysaccharide‐Based Polymers
in Cosmetics
in
Skin Care Cosmetics
Skin Care Cosmetics
3 Synthetic Polymers in Cosmetics
3.
S th ti P l
i C
ti
Ampa Jimtaisong, PhD
School of Cosmetic Science
Mae Fah Luang University
2
Elements of Polymer Science
Elements of Polymer Science
• Polymers are molecules consisting of a large number of identical low molar mass units, named repeat units, that are connected covalently. covalently
• If ‐A‐ is the base unit, then a polymer molecule or macromolecule is represented by:
——‐A‐A‐A‐A‐A‐A———— or — (A)n—
• They are usually classified according to their use
– thickening agents
– film formers
fil f
– resinous powders
– humectants
3
Elements of Polymer Science
4
Elements of Polymer Science
• Natural polymers, gums and resins
• Problems of using natural polymers
– Used in the industry since the early 1940s as water‐soluble binders, thickeners, and film forming agents. – Today’s products ‐
d ’
d
the growing consumer demand h
i
d
d
for ‘‘natural products.’’ – Drawbacks of natural polymers • vary in purity & physical appearance
• relatively expensive (compared to common synthetic polymers)
5
– 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
Elements of Polymer Science
1. Biopolymers‐Proteins and Polypeptides.
• Natural Polymers or Biopolymers
• Proteins: the repeat units in proteins are amino acids.
– Proteins and Polypeptides
• Amino acids in proteins are linked by an amide linkage between the amino group of one molecule and the
between the amino group of one molecule and the carboxyl group of another. – Polysaccharides
• Synthetic Polymers
• This amide bond is often called peptide bond. 7
8
9
10
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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 and contain amino acid residues and
carbohydrates
• Lipoproteins contain amino acid residues and lipids • Proteins that possess catalytic activity‐> enzymes.
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 Elements of Polymer Science
Definitions and Nomenclature
• Homopolymers are derived from one type of monomer.
2. Synthetic Polymers
• Considering the application of polymers: (1) plastics
(2) fib
(2) fibers
(3) rubbers
• 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 • Random
• Alternating
• Diblock
• Triblock
• Graft
Schematic composition
Polysaccharide‐Based Polymers
Polysaccharide‐
in Cosmetics
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Outline
INTRODUCTION
• Polysaccharides perform a myriad of cosmetic functions:
• INTRODUCTION
• POLYSACCHARIDE STRUCTURE
–
–
–
–
• POLYSACCHARIDES FUNCTIONALITY
– Anionic Polysaccharides
Rheology modifiers
Suspending agents
Hair conditioners
Hair conditioners
Wound‐healing agents
• They moisturize, hydrate, emulsify, and emolliate. – Cationic Polysaccharides
– Nonionic Polysaccharides
– Amphoteric Polysaccharides
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POLYSACCHARIDE STRUCTURE
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? •
Polysaccharides are sometimes referred to as ‘‘polyglycans’’ or ‘‘hydrocolloids.’’
•
‘‘Hydrocolloids’’ ‐ for food use. •
Monomers = monosaccharides (
Monomers
= monosaccharides (‘‘one
one sugar’’) in polysaccharide chemistry
• Does it complex with other components of the formulation? 19
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Monosaccharides & Polysaccharides
POLYSACCHARIDE STRUCTURE
Monosaccharides & Polysaccharides
Name
R1
R2
R3
R4
R5
R6
R7
D-Glucose
H
OH
OH
H
H
OH
CH2OH H
R8
D-Glucuronic acid H
OH
OH
H
H
OH
CO2H
D-Mannose
H
OH
H
H
OH
CH2OH H
OH
H
D-Mannuronic acid OH
H
OH
H
H
OH
CO2H
D-Galactose
OH
OH
H
OH
H
CH2OH H
H
D-Galacturonic acid H
OH
OH
H
OH
H
CO2H
L-Guluronic acid OH
H
OH
H
H
OH
H
21
H
H
CO2H
22
Anionic Polysaccharides
POLYSACCHARIDES FUNCTIONALITY
• Anionic Polysaccharides
1. Naturally Occurring Anionic Polysaccharides
• Cationic Polysaccharides
2. Seminatural Anionic Polysaccharides
• Nonionic Polysaccharides
Nonionic Polysaccharides
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Anionic Polysaccharides
Anionic Polysaccharides
a. Alginic acid (Alginates).
• Isolated from marine brown algae and from bacterial fermentation
• Comprised of two different monosaccharides:
Comprised of two different monosaccharides:
1. Naturally Occurring Anionic Polysaccharides
a. Alginic acid (Alginates).
b. Pectin.
c Carrageenans
c. Carrageenans.
d. Xanthan Gum.
e. Hyaluronic Acid and Chondroitin Sulfate.
f. Arabic, Karaya, and Tragacanth Gum.
β ‐D‐(1,4)‐mannuronic acid, 4
α ‐L‐(1,4)‐guluronic acid, 5 25
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Anionic Polysaccharides
Anionic Polysaccharides
a. Alginic acid (Alginates).
a. Alginic acid (Alginates).
Partial structure of alginic acid showing β-d-(1,4)-mannuronic acid, 4, and α-l-(1,4)guluronic acid, 5, residues.
Junction zones formed between alginic acid and Ca2+ ions.
27
sodium alginate, calcium alginate
Anionic Polysaccharides
Anionic Polysaccharides
a. Alginic acid (Alginates).
Formulations that employ alginates must control polyvalent metal ion concentrations through the use of sequestrants such as q
•
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ethylenediaminetetraacetic acid (EDTA), to optimize viscosifying effects of the alginate.
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a.
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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Anionic Polysaccharides
•alginates are not stable at pH<3.0 owing
to hydrolysis of the glycosidic bonds
holding the polysaccharides together.
1. Naturally Occurring Anionic Polysaccharides
a. Alginic acid (Alginates).
b. Pectin.
c Carrageenans
c. Carrageenans.
d. Xanthan Gum.
e. Hyaluronic Acid and Chondroitin Sulfate.
f. Arabic, Karaya, and Tragacanth Gum.
•unstable at high pH (above 10)
Effect of pH on alginate solution viscosity
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Anionic Polysaccharides
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)
b. Pectin.
Partially nonionic
Partial structure of pectin showing a-d-(1,4)galacturonic acid, 6, and a-l-rhamanose,7.
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Anionic Polysaccharides
Anionic Polysaccharides
b. Pectin.
b. Pectin.
• Pectin is sold in grades designated by methyl ester level.
• Pectin is well suited for low‐pH applications considering its source (functions ideally at pHs near 3.5)
• Lower levels of ester groups make the pectin more anionic.
• Pectin behaves much like alginic acid when its methyl ester l l
levels are below 50%; it forms turbid gels in the presence of b l 50% i f
bid l i h
f
divalent metal ions, calcium in particular. • Below
Below this pH, it suffers from hydrolysis and in highly alkaline this pH, it suffers from hydrolysis and in highly alkaline
solutions, hydrolysis of the ester is rapid. • At high methyl 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
Anionic Polysaccharides
c. Carrageenans.
1. Naturally Occurring Anionic Polysaccharides
• The carrageenans are isolated from marine red algae.
a. Alginic acid (Alginates).
b. Pectin.
c Carrageenans
c. Carrageenans.
d. Xanthan Gum.
e. Hyaluronic Acid and Chondroitin Sulfate.
f. Arabic, Karaya, and Tragacanth Gum.
• At least seven varieties of carrageenans are known, differentiated by Greek letters.
• Th
The carrageenans of greatest commercial interest are f
t t
i li t
t
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 Polysaccharides
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Anionic Polysaccharides
c. Carrageenans.
c. Carrageenans.
Carrageenan type
R1
Kappa (strong, rigid gels) OH
R2
OSO3-
R3
O
R4
OH
R5
CH2
Iota (soft gels)
OH
OSO3-
O
OSO3-
CH2
Lambda
OSO3-
OH
OH
OSO3-
CH2OSO3-
Anionic, highly acidic, hydrophilic
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Anionic Polysaccharides
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Anionic Polysaccharides
d. Xanthan Gum.
1. Naturally Occurring Anionic Polysaccharides
• Bacterial fermentation
a. Alginic acid (Alginates).
b. Pectin.
c Carrageenans
c. Carrageenans.
d. Xanthan Gum.
e. Hyaluronic Acid and Chondroitin Sulfate.
f. Arabic, Karaya, and Tragacanth Gum.
• 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
Anionic Polysaccharides
d. Xanthan Gum.
1. Naturally Occurring Anionic Polysaccharides
a. Alginic acid (Alginates).
b. Pectin.
c Carrageenans
c. Carrageenans.
d. Xanthan Gum.
e. Hyaluronic Acid and Chondroitin Sulfate.
f. Arabic, Karaya, and Tragacanth Gum.
Partial structure of xanthan g
gum showing
gβ
β-d(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.
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Anionic Polysaccharides
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Anionic Polysaccharides
e. Hyaluronic Acid and Chondroitin Sulfate.
e. Hyaluronic Acid and Chondroitin Sulfate.
• Hyaluronic acid and chondroitin sulfate are isolated from various animal tissues. • Hyaluronic acid and chondroitin sulfate are covalently bound with various proteins in the animal tissue ‐
• Cosmetic Hyaluronic acid is also commercially manufactured b b t i lf
by bacterial fermentation. t ti
‘‘proteoglycans.’’ • The unique acetylated‐amine‐containing monosaccharide • Hyaluronic acid classified these polysaccharides as glucosaminoglycans – occur in the dermis of the skin (amino‐containing sugars). – being cellular turgidity (because of its water‐binding capacity) and lubrication.
– play a key role in wound healing.
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Anionic Polysaccharides
Anionic Polysaccharides
e. Hyaluronic Acid and Chondroitin Sulfate.
Polysaccharide
Hyaluronic acid
Chondroitin-4-sulfate
Chondroitin-6-sulfate
R1
H
SO3H
comprised of two repeating units: β-D-(1,4)-glucuronic acid (14)
N-acetyl-β-d-(1,3)-glucosamine (15)
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1. Naturally Occurring Anionic Polysaccharides
a. Alginic acid (Alginates).
b. Pectin.
c Carrageenans
c. Carrageenans.
d. Xanthan Gum.
e. Hyaluronic Acid and Chondroitin Sulfate.
f. Arabic, Karaya, and Tragacanth Gum.
R2
H
H
SO347
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Anionic Polysaccharides
Anionic Polysaccharides
f. Arabic, Karaya, and Tragacanth Gum.
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.
• Arabic gum (Acacia)
¾ relatively low molecular weight‐ high levels solids ‐ without significant viscosity buildup. ¾ dissolves in water at > 50 wt% solids ‐ flowable. ¾ its maximum viscosifying effect near pH 6.0
¾ the viscosity drops quickly ‐ pH becomes higher or lower. ¾ Multivalent cations reduce the viscosity of solutions of arabic gum, but the gum will not precipitate
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Anionic Polysaccharides
Anionic Polysaccharides
f. Arabic, Karaya, and Tragacanth Gum.
• Gum karaya
¾ gum karaya swells in water and develops significant viscosity even at low concentration. ¾ stickiness accompanies the swelling‐denture adhesives.
¾ performs best at pH values between 7 and 9 ¾ 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. f. Arabic, Karaya, and Tragacanth Gum.
• Gum tragacanth
¾ shares many of the functional properties found in xanthan gum. ¾ At low concentrations it produces high solution viscosities.
¾ Tragacanth has high pH stability
Tragacanth has high pH stability
¾ its viscosity‐ thins as the temperature increases. ¾ Tragacanth strongly binds multivalent cations: including calcium, precipitate the polysaccharide from solution.
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Anionic Polysaccharides
Anionic Polysaccharides
1. Naturally Occurring Anionic Polysaccharides 2. Seminatural Anionic Polysaccharides
a. Cellulose Gum (Sodium Carboxymethylcellulose)
b C b
b. Carboxymethylchitin
h l hi i
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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
Cellulose
is composed of one repeating monosaccharide, β‐d‐
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.
Anionic Polysaccharides
a. 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 Polysaccharides
Anionic Polysaccharides
a. Cellulose Gum or Sodium Carboxymethylcellulose (CMC)
•
CMC forms association complexes with strongly anionic surfactants
–
1. Naturally Occurring Anionic Polysaccharides
2. Seminatural Anionic Polysaccharides
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
•
–
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a. Cellulose Gum (Sodium Carboxymethylcellulose).
b. Carboxymethylchitin.
At the point of charge neutralization, phase separation occurs. •
Stable at pH 4‐10
•
Sensitive to heat, electrolytes
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Anionic Polysaccharides
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Anionic Polysaccharides
b. Carboxymethylchitin.
b. Carboxymethylchitin.
• Carboxymethylchitin (CMCh), in Japan ‐ ‘‘chitin liquid’’.
• It is manufactured by the carboxymethylation of chitin
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POLYSACCHARIDES FUNCTIONALITY
• Anionic Polysaccharides
• Cationic Polysaccharides
• Nonionic Polysaccharides
Nonionic Polysaccharides
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Cationic Polysaccharides
Cationic Polysaccharides
Chitosan
1. Naturally Occurring Cationic Polysaccharides
• It is not cationic or water‐soluble unless the pH < 7.0 a. Chitosan.
• It is neutralized at these low pH values to the water‐soluble 2. Seminatural Cationic Polysaccharides
chitosonium salt (22). a. Cationic Hydroxyethylcellulose
C ti i H d
th l ll l
•
• Commercially, the polysaccharide is often found neutralized C
i ll th
l
h id i ft f
d
t li d
Cationic HEC, 27, more commonly known by its INCI name, with a cosmetically functional carboxylic acid such as lactic polyquaternium‐10, is used as a conditioner delivered from acid or glycolic acid, α‐hydroxy acids, shampoos & conditioners. •
• Chitosan, employed as its salt, has strong substantivity to The cationic HEC, 28 ( polyquaternium‐4) is found as a conditioning anionic surfaces like skin and hair. & fixative adjuvant in hair fixatives.
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chitin
chitosan
Chitosan salts
Formation of chitosan, 21, and chitosan salts, 22, from native chitin, 19.
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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. forms strong water‐insoluble
insoluble associative associative
• Chitosan forms strong water
complexes with most anionic surfactants.
• Evidence suggests that chitosan aids in the healing of wounds and damaged skin.
ChitoGauze TM
The Hemostatic HemCon® Bandage
The chitosan bandage
Battlefield Band‐Aids
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Nonionic Polysaccharides
POLYSACCHARIDES FUNCTIONALITY
1. Naturally Occurring Nonionic Polysaccharides
• Anionic Polysaccharides
a. Starch.
b. Cyclodextrins.
• Cationic Polysaccharides
• Nonionic Polysaccharides
Nonionic Polysaccharides
2 S i t lN i i P l
2. Seminatural Nonionic Polysaccharides
h id
a. The Cellulose Ethers (5 sub types)
b. Nitrocellulose
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Nonionic Polysaccharides
amylopectin
a. Starch.
• Starch is an energy‐storage polyglycan
• Corn, potato, rice, wheat, and tapioca
• It is composed of amylopectin and amylose
• Starch
Starch is an inexpensive, nontoxic polyglycan used 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.
amylose
The higher the ratio of amylose to amylopectin, the greater the thickening effect.
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Nonionic Polysaccharides
b. Cyclodextrins
• Cyclodextrins are used extensively in cosmetic and drug delivery applications. • The interior portion of the cyclodextrin is a lipophilic (‘‘oil‐
loving’’)) environment. loving
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‐soluble
cyclodextrins.
Cyclodextrin
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Nonionic Polysaccharides
Nonionic Polysaccharides
a. The Cellulose Ethers 1. Naturally Occurring Nonionic Polysaccharides
The most popular and useful rheology control materials employed in the personal care industry. •
a. Starch.
b. Cyclodextrins.
2 S i t lN i i P l
2. Seminatural Nonionic Polysaccharides
h id
a. The Cellulose Ethers (5 sub types)
b. Nitrocellulose
•
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.
(Handout)
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Nonionic Polysaccharides
Nonionic Polysaccharides
a. The Cellulose Ethers 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)
•
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 HPC
solubility 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.
HPC can be further treated with methyl chloride to afford •
hydroxypropylmethylcellulose (HPMC) Handout
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Nonionic Polysaccharides
Nonionic Polysaccharides
a. The Cellulose Ethers a. The Cellulose Ethers The solubility of most cellulose ethers decreases as their •
i.
ii.
iii
iii.
iv.
v.
solution temperature increases.
As the temperature continues to increase, finally the p
,
y
•
polysaccharide collapses upon itself and precipitates from solution. Hydroxyethylcellulose.
Hydroxypropylcellulose
Methylcellulose
Hydroxypropylmethylcellulose
Ethylhydroxyethylcellulose
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 Polysaccharides
i.
•
•
•
•
Nonionic Polysaccharides
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.
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 Polysaccharides
Nonionic Polysaccharides
iii. Methylcellulose (MC)
•
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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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 Polysaccharides
Nonionic Polysaccharides
iv. 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.
1. Naturally Occurring Nonionic Polysaccharides
a. Starch.
b. Maltodextrins/Cyclodextrins.
2 S i t lN i i P l
2. Seminatural Nonionic Polysaccharides
h id
a. The Cellulose Ethers (5 sub types)
b. Nitrocellulose
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Protein‐Based Polymers
Nonionic Polysaccharides
b. 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. y
• Levels of commercial nitration are extremely critical because cellulose, nitrated to levels greater than 12% nitrogen‐ an explosive.
I. Animal Sources
a) Collagen
b) Elastin
c) Keratin
d) Milk Protein
d) Milk Protein
e) Silk Protein derivatives
II. Vegetable Sources
a) Wheat Gluten
b) Soy Protein
c) Corn (Protein Isolate)
d) Casein
e) Yeast Protein
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Outline
Thickening Polymers
Synthetic Polymers in Cosmetics •
Carbomers
•
Polyvinyl pyrrolidone
•
Polyvinylpyrrolidone‐vinyl acetate
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Synthetic Polymers
Synthetic Polymers
Carbomer Carbomer ƒ Carbomer gels are most viscous between pH 6 and 11.
ƒ Known as Carbopols, carboxypolymethylene, carboxyvinyl polymer or acrylic acid polymer
ƒ The viscosity is reduced on lowering the pH to below 3 or rising above 12.
ƒ 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. ƒ Electrolytes also reduce the viscosity of carbopol dispersions. Electrolytes also reduce the viscosity of carbopol dispersions
ƒ Carbomer is susceptible to oxidation especially on exposure to light and hence formulations should be stabilized by addition of appropriate antioxidants and chelating agents. 91
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Synthetic Polymers
Synthetic Polymers
Polyvinylpyrrolidone (PVP)
Carbomer ƒ Several viscosity grades are available and the usual concentration used varies from 0.1% to 4% as suspending agent.
di
ƒ It can dissolve in water and a variety of organic solvent.
ƒ It has good hygroscopicity, film‐forming capability, complexing ability and physiology compatibility
Carbomer 934
Carbomer 940
Carbomer 941
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Synthetic Polymers
Synthetic Polymers
Polyvinylpyrrolidone‐vinyl acetate
Polyvinylpyrrolidone (PVP)
copolymer (PVP/VA)
ƒ Cosmetics: PVP‐K series can be used as film‐
forming agent, viscosity‐enhancement agent, lubricator and adhesive
lubricator and adhesive. ƒ PVP‐K30, PVP‐K85, PVP‐K90
ƒ They are the key component of hair sprays, mousse, gels and lotions & solution, hair‐dying reagent and shampoo in hair‐care products.
ƒ PVP/VA forms hard, glossy, water‐removable films.
ƒ Its viscosity, softening point and water sensitivity Its viscosity softening point and water sensitivity
vary with PVP/VA ratio. 95
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1702702 (2-2009)
Nov 28-2009
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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