Loading in 5 sec....

SURFACTANTS IN SOLUTIONPowerPoint Presentation

SURFACTANTS IN SOLUTION

- 495 Views
- Updated On :
- Presentation posted in: General

SURFACTANTS IN SOLUTION. Classification of Surfactants. Anionic Cationic Zwitterionic Nonionic. Sodium dodecylsulfate (SDS). Cetylpyridinium bromide. Dipalmitoylphosphatidylcholine (lecithin). Polyoxyethylene(4) lauryl ether (Brij 30). 4 nm. Surfactant Aggregates. Normal micelles.

SURFACTANTS IN SOLUTION

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Classification of Surfactants

- Anionic
- Cationic
- Zwitterionic
- Nonionic

Sodium dodecylsulfate (SDS)

Cetylpyridinium bromide

Dipalmitoylphosphatidylcholine (lecithin)

Polyoxyethylene(4) lauryl ether (Brij 30)

Surfactant Aggregates

Normal micelles

Unimers

cylindrical

spherical

Inverted hexagonal phase

Reverse micelles

Bilayer lamella

12

10

8

CMC

6

4

2

0

0

Surfactant concentration

1

Critical Micelle Concentration

CMC

- Below CMC only unimers are present
- Above CMC there are micelles in equilibrium with unimers

Concentration

unimers

14

Osmotic pressure

12

12

10

10

8

8

CMC

6

CMC

6

micelles

4

4

2

2

0

0

0

1

Surfactant concentration

0

1

Surfactant concentration

14

Isc

12

Light scattering

10

8

CMC

6

4

2

0

0

1

Surfactant concentration

Solution Properties

Normal micelles

polar compound

non-polar compound

Solubilization- Spontaneous transfer of a compound insoluble in the bulk solvent into solution due to incorporation into the surfactant micelles

amphiphilic compound

Solubility

12

10

8

CMC

6

4

2

0

0

Surfactant concentration

1

Solubility Effects- Solubility of a poorly soluble compound increases as a result of solubilization in the micelles

An example of an HLB value calculation

- BRIJ ® 98 INCI name : oleth-20 is a 20 mole ethoxylate of oleyl alcohol
- calculate the molecular weight of the 20 moles of ethylene oxide ( one mole ETO =44 );
20 x 44 = 880

- add this number to the molecular weight of the oleyl alcohol;
880+ 270 = 1150 ( the mol. wt of BRIJ 98 )

- What percentage of 1150 is 880 ?
880/1150 = 76.5%

- 76.5% divided by 5 = 15.3
- 15.3 is the HLB value of BRIJ 98

HLB and Use of Surfactants

Amphiphilic surfactants are characterized by the hydrophilic-lipophilic balance (HLB): a relative ratio of polar and non-polar groups in the surfactant

- HLB ca. 1 to 3.5: Antifoams
- HLB ca. 3.5 to 8: Water-in-Oil Emulsifiers
- HLB ca. 7 to 9: Wetting and spreading agents
- HLB ca. 8 to 16: Oil-in-Water Emulsifiers
- HLB ca. 13 to 16: Detergents
- HLB ca. 15 to 40: Solubilizers

Required HLB

HLB needed for emulsification of the oil phase. If there are several oil ingredients the required HLB is calculated as a sum of their respective required HLB multiplied by the fraction of each.

- Calculate the required HLB for the oil phase of the following o/w emulsion: cetyl alcohol 15 g., white wax 1g. Lanolin 2 g, emulsifier (q.s.), glycerin 5 g. water 100 g.
- Required HLB Fraction
- (from reference)
- Cetyl alcohol15x15/1812.5
- White wax12x1/180.7
- Lanolin10x2/181.1
- Total required HLB14.3

HLB of Surfactant Blend

Surfactant blends are commonly used to obtain desired emulsifying properties.

- Span 60 (HLB = 4.7)
- Tween 60 (HLB = 14.9)
- Span 80 (HLB = 4.3)
- Tween 80 (HLB = 15.0)

What is the HLB of the mixture of 40 % Span 60 (HLB = 4.7) and 60 % Tween 60 (HLB = 14.9)?

Sorbitan monostearate is an ester of

sorbitol and stearic acid (synthetic wax)

Polyoxyethylenesorbitan monooleate;

Sorbitan monooleate ethoxylate

- HLB of mixture:4.7 x 0.4 + 14.9 x 0.6 = 10.8

- In what proportion should Span 80 (HLB = 4.3) and Tween 80 (HLB = 15.0) be mixed to obtain “required” HLB of 12.0?

- 4.3.(1-x) + 15.x = 12x = 0.72
- 72 % Tween 80 and 28 % Span 80

Glycerol Monostearate (HLB = 15.0) be mixed to obtain “required” HLB of 12.0?

HLB value of 3.6~4.2

dissolves in hot grease, paraffine, ethanol, chloroform, acetone and aether, the material is widely used when producing of chocolate, margarine, ice cream, skin care balsam, cold cream, hair oil and drug ointment, also lubricant for plastic processing

Shampoo (HLB = 15.0) be mixed to obtain “required” HLB of 12.0?

Ingredients (HLB = 15.0) be mixed to obtain “required” HLB of 12.0?

- Isobutane
- Cyclomethicone
- Aluminum Chlorohydrate
- Propylene Glycol Dicaprylate/Dicaprate
- Lichen extract
- Fragrance
- Quaternium-18
- Silica
- Dimethiconol

cyclomethicone (HLB = 15.0) be mixed to obtain “required” HLB of 12.0?

Propylene Glycol Dicaprylate/Dicaprate

Facial Cleanser (HLB = 15.0) be mixed to obtain “required” HLB of 12.0?

Aqua/Water

Palmitic acid

Myristic acid

Lauric acid

Stearic acid

Potassium hydroxide

PEG-7 Glyceryl cocoate

PEG-150 Distearate

Glycerin

Sodium laureth sulfosuccinate

Limonene

Linalool

Zinc PCA

Propylparaben

Propylene glycol

Disodium EDTA

NaCl

Propylene glycol (HLB = 15.0) be mixed to obtain “required” HLB of 12.0?

propyl ester of p-hydroxybenzoic acid = propylparaben

zinc salt of 2-Pyrrolidone-5-Carboxylic Acid

PEG-7 Glyceryl cocoate

Polyoxyethylene glycol glyceryl cocoate (monococoate).

PEG-150 Distearate (HLB = 15.0) be mixed to obtain “required” HLB of 12.0?

Polyethylene glycol diester of stearic acid.

Sodium laureth sulfosuccinate

Cream (HLB = 15.0) be mixed to obtain “required” HLB of 12.0?