INTODUCTION TO SURFACTANFOR COSMETICS & HOUSEHOLD GUIDANCE

DISPERSED SYSTEMS – Foams and emulsions

By : Mala Pidiyanti

CV Lidah Buaya, Magelang. 2013

Definition : Surfactants are compounds that stabilize

mixtures of oil and water by reducing the surface tension at the

interface between the oil and water molecules.

• Surfactants are AMPHIPHILIC in nature. amphi which means "double" . amphiphilic = double affinity as a polar-apolar duality

• Hydrophilic = Lipophobe Polar, hight affinity

• Hydrophobe = lipophile Non Polar, alkyl chain

PHOBE Greek roots phobos (fear)

PHIL Greek roots philos (Love)

• Tail or hydrophobic group which has little affinity for water – this group is usually hydrocarbon (alkyl) chain

• Head or hydrophilic group which has strong affinity for water & can be

neutral or charged.

The primary performance function of surfactants is the lowering of interfacial tension. Some examples:

• Cleansing

Lowering tension between dirt/oil , water, and your skin or hair

• Emulsions

Lowering tension between the oil phase and the water phase

• Dispersions

Lowering tension between particles and water or oil

CLASSIFICATION OF SURFACTANTS

1. Anionic Surfactants : mostly SOAP, sulfonates or sulfates

2. Nonionic Surfactants : mostly ethoxylated, fatty acid ester

3. Cationic Surfactants : mostly quaternary ammoniums

4. Amphoteric or zwitterionic : mostly betaines and amino acid

derivatives

A new class of surface active substance1. Polymeric surfactants or surface active polymers

2. Silicone Surfactan

- Term “Siliphilic” (silicone loving) and “Siliphobic” (silicone hating)

SURFACTAN CRITERIA FOR PERSONAL CARE OR

HOUSEHOLD PRODUCT FORMULATION

1. Application : Household, skin care, body care, hair care

Brochure

2. Category : Primary, Secondary, Tertiary

3. Foamability : Foam Booster, antifoam

4. Level of Irritant : Irritant, Mild, very mild

Mildness: nonionics > amphoterics > anionics > cationics

5. Foam character : big bubble, small bubble, dense bubble

6. After feel effect : dry, soft, powdery feel, etc

7. Electrolyte response : thickening effect, cloudy, no effect

8. Level of use

1. SOAPS AND OTHER CARBOXYLATES3 NaOH + (C17H35COO)3C3H5 3 C17H35COONa + CH2OH-CHOH-CH2OH

Triglyceride sodium stearate Glycerol

→ Tryglyceride is animal origin : Tallow, Lard

→ Monoglyceride used in industrial is commonly vegetable origin

→ NaOH Resulting solid soap for barsoap

→ KOH, Resulting liquid soap

→ C16-C18 : Hard soap, low foam, whitish and do not produce skin irritation or

dryness

→ C12 –C14 : Less hard, high foam, less whitish, cause dryness

C12 : 0 = Lauric Acid

C14 : 0 = Myristic Acid

C16 : 0 = Palmitic Acid

C18 : 0 = Stearic Acid

C18: 1 = Oleic Acid

C18 : 2 = Linoleic Acid

C18 : 3 = Linolenic Acid

ANIONIC SURFACTANTS

SOAP Making Oil Chart, Castille SoapBase oil, butter or

fat

Soft, hard or

brittle

Properties in soap usage

Coconut oil Hard large fluffy bubbles, highly cleansing, high amounts can be

too drying, makes a white bar

15-30%

Palm oil Hard a great base oil, makes a hard long lasting bar, stabilizes

lather

25-50%

Olive oil Soft/Hard makes a very gentle and mild bar, low lotion-like lather,

low cleansing, great for babies and elder folk’s skin, some

people say that high amounts of olive oil make for a slimy

or snotty feel in the shower

25-50%

Lard Hard a great base oil, makes a hard bar with a low creamy lather,

makes a white bar, stabilizes lather

25-50%

Tallow (beef) Hard a great base oil, makes a hard bar with a low creamy lather,

stabilizes lather

25-50%

Palm Kernel oil Brittle similar to coconut oil, large fluffy bubbles, highly

cleansing but milder than coconut oil

15-30%

Shea butter Hard makes a hard bar of soap, seems to add a silky feel to the

lather, stabilizes lather

5- 15%

Castor oil Soft helps suspend/hold the lather from coconut oil, adds

creaminess, high amounts will cause a bar of soap to be

sticky and have a drag when using it in the shower

5-10%

ANIONIC SURFACTANTS

2. SULFATEe.g., : sodium lauryl surfate , sodium laureth sulfate (Texapon, ECOSOL, IMEX), ,

Di-sodium Ricinoleate sulfate

3. SULFONATE e.g., : linear alkylbenzene sulfonates (LAS), ABS, sodium laureth sulfosucinate

(Makanate EL)

ANIONIC SURFACTANTS

4. OTHER ANIONIC SURFACTANTSI. ORGANO PHOSPHORED SURFACTANTS

e.g., : Potasium Laureth Phospate (Dermalcare 213L/K)

II. SARCOSIDES OR ALCYL AMINO ACIDS

e.g., : Sodium lauroil sarcosinate (Crodasinic LS 30), Cocamide DEA, Cocamide

MEA

The most used synthetic product is lauryl sarcosinate, which is both a strong

bactericide and a blocking agent of hexokinase (putrefaction enzyme). Since it

is not cationic, it is compatible with anionic surfactants, and it is used in tooth

paste and "dry" shampoos for carpets and upholstery.

NONIONIC SURFACTANTS

NONIONIC SURFACTANTS : Mostly For Cream Emulsion

1. ETHOXYLATED ALCOHOLS AND ALKYLPHENOLS

general formula RXH, that can ionize as RX-.e.g., : Ethoxylated Linear Alcohols, Ethoxylated Alkyl Phenols, Cetyl Alcohol,

oleth-20 , steareth-2(Brij )

2. FATTY ACID ESTERSe.g., : Glycerol monostearate , PEG-100 glyceryl stearate (commecial name :

Simulsol), sorbitan esters (comercial name : Span, Tween)

3. NITROGENATED NONIONIC SURFACTANTSe.g., ; Tertiary amine oxides, ethoxylated imide

NONIONIC SURFACTANTS

Advantages of Nonionic type surfactants :

1. As a class they are usually the least irritating

2. They are compatible with all the other type surfactants

3. They are compatible with salts

4. They are compatible at the widest pH range

5. They are pre-formed

6. As a class they are the most versatile

CATIONIC SURFACTANS1. QUATERNARY COMPOUNDS or QUATS.

They are not good detergents nor foaming agents, and they cannot be mixed in

formulations which contain anionic surfactants, with the exception of non

quaternary nitrogenated compounds, or when a catanionic complex synergetic

action is sought.

Quartenary compound (quats) Benzalkonium Chloride

The quats kill bacterial spores but rahter than inhibit their growth. They form a

residual antimicrobial film after being applied to surfaces. They attached to the

bacteria and cause the cytoplasmic membrane to leak, damaging and kill the

bacteria. The quats are low in toxicity, non iriitant to skin and can be neutralized

or made ineffective by using any anionic detergent.

Quat sanitizers are generally more effective in the alkaline pH range. However the

effect of pH may vary with bacterial species, with gram-negative bacteria being

more susceptible to quats in the acid pH range and gram-positive microbes in the

alkaline range.

Confusion in the marketplace

• Bacteriostatic

Means “stops bacterial growth‟‟‟‟ examples are sulfamethoxazole which blocks nucleic acid synthesis or chloramphenicol which blocks amino acid synthesis. Such agents prevent bacteria reproducing but do not necessarily kill them outright so they can still produce toxins and/or spoil foods.

• Bactericidal

Agents kill bacteria rather than just inhibit their growth. We tend to use quaternary ammonium compounds (quats) to do this in cleaning products but there are others such as triclosan which uses a chlorinated phenol (and so it is less soluble in water).

• Antibacterial

Means whatever you want it to. It is a woolly, non specific term and does not carry the specificity or weight of the two alternatives above

CATIONIC SURFACTANSQuats inactivated by anionic detergents (soaps), by many nonionic detergents, and by calcium, magnesium, ferric, and aluminum ions. Also, they are not recommended to be used in hard water. Effective levels are at 200 ppm. However, an increase in alkalinity through formulation with compatible detergents may enhance the bactericidal activity of the quats

2. OTHER CATIONIC SURFACTANCationic class contains aromatic or saturated heterocycles is N-dodecylpyridinium chloride or 1-hexadecyl piridium Chloride (INCI: Cetyl PiridiumChloride) is used as batericide and fungicide. If a second hydrophilic group is added (amide, ethylene oxide) the product is the both a detergent and a bactericide. is compatible with anionic formulas since it is not stricly cationic.

They also found as antistatic agents in fabric softeners and hair rinse formulas. E.g., Ester quats-sunqat TE 90 (softening agent), CTAC or BTAC as anti static agent

CATIONIC SURFACTANS

3. NITROGENATED SURFACTANTS WITH A SECOND HYDROPHILE

Cationic surfactants cannot be mixed in general with anionics, since they

react with one another to produce insoluble catanionic compounds. This is

quite a practical problem since most inexpensive formulas contain anionics of

the sulfonate or sulfate ester type, and it would be desirable to add to them

some cationic substance for softening pupose.

The incompatibility problem is circumvented by using a nitrogenated

surfactant of the amine type, i.e. with no actual positive ion, whose water

solubility is enhanced by incorporating a second polar group.

3.1 ALKANOL-AMIDES

They are among the best foam boosters available at neutral and alkaline

pH, with additional corrosion inhibition properties at neutral pH. Fatty acid

alkanol-amides are commonly used as foaming and wetting agents in hand

dish-washing detergents, shampoos and bar soaps, particularly the diethanol-

lauryl (coco) amide. E.g., : Cocamide DEA, cocamide MEA

AMPHOTERIC SURFACTAN

Amphoteric or zwitterionic surfactants have two functional group, one anionic and one cationic. In most cases it is the pH which determines which of the groups would dominate. with a minimum

of interfacial activity and a concomitant maximum of water solubility

Amphoteric surfactants, particularly the aminoacidones are quite biocompatible, and are used in

pharmaceuticals and cosmetics.

AMPHOTERIC SURFACTAN

1. AMINO PROPIONIC ACIDSThe general formula for amino propionic acids is RN+-CH2-CH2-COO- . Their isoelectric point is around pH = 4. They are soluble in acid or alkaline solutions. They adsorb on skin, hair, and textile fibers. They are used as antistatic and lubricants for hair and fabrics. The dodecyl amino propionicacid is used in cosmetics as wetting agent and bactericide. At high pH it is good detergent and foaming agent. However, due to their carboxylic acid groups, these surfactants are sensitive to divalent cations.

2. IMIDO PROPIONIC ACIDSTheir general formula is HOOC-CH2-CH2-RN+H-CH2-CH2-COO-. Their isoelectric point is around pH = 2-3. They are thus more water soluble than the previous ones. They are used as textile softeners. Dicarboxylic compounds of alkyl imidazole, in which the alkyl group is located on the carbon placed between the nitrogen atoms, are used in cosmetics and de luxe soap bars.

AMPHOTERIC SURFACTAN

3. QUATERNIZED COMPOUNDS

Quaternized compound have similar structures. The most important are betaines and sulfobetaines or taurines, which have a single methylene group between the acid and the quaternary ammomium.

These surfactants are amphoteric at neutral and alcaline pH, and cationic at acid pH (at which the carboxylic acid is not ionized). Since the nitrogen atom is quaternized, these surfactants always display a positive charge. They tolerate a high salinity, particularly divalent cations, e.g. calcium and magnesium. They are the most used class of amphoteric surfactants. They are found in softeners for textiles, hair rinse formulas, and corrosion inhibition additives. They are good foam boosters because of their cationic characteristics. Sulfobetaines have an anionic group (sulfonate) which tolerates calcium ions, and are used as lime soap dispersing agents (LSDA) in de luxe soap bars and detergents.

Polymeric surfactants

These surfactants have many uses, in particular as colloid and nanoemulsion

dispersants, wetting agents, detergents.

There are two main configurations: "block" and "graft“, where H and L

represent hydrophilic and lipophilic monomer units.

The result is a macromolecular surfactant. Although the hydrophilic and

lipophilic parts are quite separated, the polymer polarity segregation is not that

obvious since both groups are slightly polar

However most polimeric surfactants belong to the second (graft) type,

particularly synthetic products such as polyelectrolytes which are not strictly

surfactants or are not used for their surfactant properties

1. CMC

2. Aristoflex AVC

3. Hostacerin SAF : Mineral oil, isopropyl palmitate,

trilaureth-4 phosphate, rapeseed oil sorbitol esters, ammonium

acryloyldimethyltaurate/VP copolymer

Polymeric surfactants, an example :

SILICONE SURFACTAN

Advantage :• Improved surface tension reduction – 20 dynes/cm2 rather than the

30+ dynes/cm2

• Wetting in water, and oil based systems.

• Emulsification properties

• Film forming properties

• Irritation mitigation

• Improve skin feel

Dimethicone Copolyol

The silicone soluble portion is shown in red, the water soluble portion is shown in blue

Dimethicone Copolyol (DMC)

Silicone surfactants are no longer “silicone surfactants*” when the amount

of silicone in the molecule is too low to effect surface tension. At that point

the molecules simply become fatty surfactants that have silicone attached.

Lower molecular weight DMC have faster wetting times, products can be

easily selected that provide both efficient wetting and low ocular irritation.

Unfortunately, many DMC are poor wetting agents. This is due to the fact that

most commercial products have a molecular weight in excess of 2500.

INCI Name MW Surface Tension

PEG-8 Dimethicone 800 21.9 Dynes/cm2

PEG-8 Dimethicone 6353 28.1 Dynes/cm2

PEG-8 Dimethicone 12.500 31.0 Dynes/cm2

PEG-8-PG-coco-Glucoside Dimethicone :

The sugar (APG) portion of the molecule provides good foam and a high degree of substantivity to hair and skin. it provides an outstanding skin feel when applied from body wash formulations. These products show that they provide foaming and slip while actually lowering the irritation of formulations. They show excellent toxicological properties as well as an ability to mitigate irritation in harsh formulations

APPLICATIONS

• Skin Care Products: creams, lotions, tonics, shower gels, etc.

• Hair Care Products: shampoos, conditioners, hair tonics, hair creams, etc.

• Sun Care Products: pre and post sun care creams, lotions, gels, etc.

• Make-up Products: foundations, lipsticks, etc.

• Health Care

LATIHAN SOAL