Determining HLB Value
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Transcript of Determining HLB Value
By : Mala Pidiyanti.R&I Dept., CV LIDAH BUAYA
Januari 2014
FORMULATING WITH HLB VALUE CALCULATION
Hydrophile Lipophile Balance
• The relationship ( or balance ) between the hydrophilic portion of the nonionic surfactant to the lipophilic portion
• It was invented in 1954 by William C. Griffin of the Atlas Powder Company ( bought by ICI in 1971 )
• As a guidance to good emulsification performance
• HLB values are calculated for nonionic surfactants only
• The HLB value is an indication of the solubility of the surfactant
The chemistry of a nonionic surfactant ?• Each surfactant has a hydrophilic group and a lipophilic group• The hydrophilic group is usually a polyhydric alcohol or
ethylene oxide• The lipophilic group is usually a fatty acid or a fatty alcohol
• The lower the HLB value the more lipophilic or oil soluble the surfactant is
• The higher the HLB value the more water soluble or hydrophilic the surfactant is
• HLB Value range is between 1 - 20
SURFACTAN PROPERTIES BASED ON HLB VALUE
The HLB value can be used to predict the surfactant properties of a molecule :
A value from 4 - 8 indicates an anti-foaming agent A value from 7 - 11 indicates a W/O (water in oil) emulsifier A value from 12 - 16 indicates O/W (oil in water) emulsifier A value from 11 - 14 indicates a wetting agent A value from 12 - 15 indicates a detergent A value of 16 - 20 indicates a solubiliser or hydrotrope
HLB/WATER DIPERSIBILITY RELATIONSHIP
Calculating “HLB VALUE” with Grifin’s Methods
Another Methods of Calculating HLB Value
• Calculate the hydrophilic groups of the surfactant on a molecular weight basis and then divide that number by 5
Example : oleth-20 is a 20 mole ethoxylate of oleyl alcoholthe 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 (oleyl alcohol) = 1150 ( the mol. wt)
• Percentage of 20 mole ethoxylate from 20-oleth? 880/1150 = 76.5%
• 76.5% divided by 5 = 15.315.3 is the HLB value of oleth-20
HLB SYSTEM : HLB VALUE MEET HLB REQUIRED
√ HLB Value : The balance between the hydrophilic portion to the lipophilic portion of the nonionic surfactant
√ HLB Required : the value of HLB that required by every Lipophilic ingredient in the O/W emulsions.
√ HLB System is matching the HLB value of your surfactant with the Lipohilic ingredient in the emulsion system.
Some general “HLB required” for O/W emulsions
OIL (LIPOPHILIC) CLASS REQUIRED HLB
Vegetable Oil Family 6-8
Silicones Oil 8-12
Petroleum Oil and wax 10 -12
Typical Ester Emmolient 12-14
Fatty Acid and Fatty alcohol 14-16
Formulating with HLB value• mixing unlike oils together
– use surfactants with HLB’s of 1 to 3• making water-in-oil emulsions
– use surfactants with HLB’s of 4 to 6• wetting powders into oils
– use surfactants with HLB’s of 7 to 9• making self emulsifying oils
– use surfactants with HLB’s of 7 to 10• making oil-in-water emulsions
– use surfactant blends with HLB’s of 8 to16• making detergent solutions
– use surfactants with HLB’s of 13 to 15• for solubilizing oils ( micro-emulsifying ) into water
– use surfactant blends with HLB’s of 13 to 18
CALCULATING HLB VALUE IN EMULSION SYSTEM
Example :A simple O/W lotion formula
– mineral oil 8 %– caprylic/capric triglyceride 2 %– isopropyl isostearate 2 %– cetyl alcohol 4 %– emulsifiers 4 %– polyols 5 %– water soluble active 1 %– water 74 %– perfume q.s.– preservative q.s.
Calculations:add up the oil phase ingredients
– mineral oil 8 %– caprylic/capric triglyceride 2 %– isopropyl isostearate 2 %– cetyl alcohol 4 %
» 16– emulsifiers 4 %– polyols 5 %– water soluble active 1 %– water 74 %– perfume q.s.– preservative q.s.
Calculations:divide each by the total to get the contribution to the oil phase
• Mineral oil 8 / 16 = 50%
• caprylic/cap. trig. 2 / 16 = 12.5%
• isopropyl isostearate 2 / 16 = 12.5%
• cetyl alcohol 4 / 16 = 25%
CONCLUSIONS :
• One you know the required HLB of individual oils it is easy to mathematically calculate the required HLB of a mixture of oils
• knowing the required HLB of an oil or an oil mixture means that you can use the least amount of surfactant to achieve emulsification
• Surfactant choice considerations: 1. Chemical type
– ester VS ether– lipophilic group, e.g. lauryl VS stearyl
2. Physical form– liquid VS solid VS beads
3. FDA “status” ( if any )– is there an N. F. monograph
4. Price VS function 5. Blend VS single surfactant 6. Efficiency of the surfactant
Surfactant choice considerations:
1. Philip Haw, 2005, “THE HLB SYSTEM, A TIME SAVING GUIDE TO SURFACTANT SELECTION’, UNIQEMA
2. Bonnie Pyzowski, Mani Dhamdhere, “Rapid HLB-Based Method for Formulating and Improving Emulsion Stability”, www.angus.com