The HLB value can be used to predict the surfactant properties of a molecule:
- < 10 : Lipid-soluble (water-insoluble)
- > 10 : Water-soluble (lipid-insoluble)
- 1 to 3: anti-foaming agent [1]
- 3 to 6: W/O (water in oil) emulsifier
- 7 to 9: wetting and spreading agent [1]
- 13 to 16: detergent [1]
- 8 to 16: O/W (oil in water) emulsifier
- 16 to 18: solubiliser or hydrotrope [1]
What is the HLB of a surfactant molecule?
Surfactant molecules have both hydrophilic (water loving) and lipophilic (oil loving) groups. The HLB system, which stands for “Hydrophilic Lipophilic Balance”, indicates how the proportion of those groups will affect surfactant behavior in emulsions. HLB numbers correspond to the degree of water or oil solubility of a particular surfactant.
What are the basic principles and relationships of HLB?
The basic principles and relationships related to HLB are detailed such as the predicting and experimental methods for the determination, as well as the achievements of development and applications of surface active agents. Emulsifying Agents* / classification
What is the HLB of essential oil emulsions with high HLB?
A light bluish reflection was observed only in the emulsion with higher HLB value (16.7), which also showed the lowest droplet size (246.6 nm). These emulsions are useful to the evaluation of required HLB of I. verum essential oil, which was the aim of this work.
What are the factors affecting the HLB of an emulsifier?
The HLB does not take account of certain factors such as: ionization as a function of the pH, influence of temperature, concentration of emulsifier, possible interaction with other molecules and finally the respective concentrations of the contiguous and dispersed phases. Emulsifiers can be classified on the basis of their HLB value:
What is the importance of calculating the total or required HLB in an emulsion?
The HLB number is a semi-empirical scale for selecting surfactants (Griffin, 1949). On this context, development of emulsions with blends of surfactants on a wide range of HLB values can provide a satisfactory determination of the required HLB of lipophilic phase, such as essential oils.
How do you use HLB value?
HLB= E / 5 can be calculated with this equation. E: Percentage by weight of ethyleneoxide • HLB value of fatty acid esters of polyhydric alcohols such as glyceryl monostearate, HLB= 20 [1-(S / A)] is calculated with that equation. The HLB values of some of the most frequently used surfactants are shown in Table 11.1.
What is required HLB?
The Required HLB of the oil is equal to the calculated HLB value of the binary blend of emulsifiers that provides the most stable and aesthetically pleasing emulsion. Table 2: HLB values for mixtures of two stearate ester emulsifiers. One is lipophilic (sorbitan stearate) and the other hydrophilic (polysorbate 20).
What is a HLB system?
The HLB system, which stands for “Hydrophilic Lipophilic Balance”, indicates how the proportion of those groups will affect surfactant behavior in emulsions. HLB numbers correspond to the degree of water or oil solubility of a particular surfactant. Lower HLB numbers indicate better oil (non-polar) solubility.
Why alcoholic KOH is used in the determination of HLB value?
Alcoholic KOH is used, because surfactantsare freely soluble in alcohol than in water. The solubility improved by alcohol hydrolysis is effective one.
What is the HLB of an emulsifier blend consisting of 25% of Span 20 and 75% of Tween 20?
What is the HLB value of an emulsifier blend consisting of 25% span20 (HLB 8.6) and 75% tween20 (HLB 16.7). ) 75 = 100 (x – 8.6) / (16.7 – 8.6) 75 = 100x – 860 / 8.1 X = 14.67 Problem 3 Page 15 Calculate the HLB value of a mixture consisting of 45 g of span80 (HLB 4.3) and 55 g of polysorbate (tween 80) (HLB 15).
What is the HLB value of detergent?
The HLB of the nonionic surfactant is set to be between 13 and 16 which is the standard HLB range for detergent products (Griffin, 1949) and to ensure that the product exhibits high detergency and forms a clear solution (Fung et al., 2007).
What is the HLB value of Tween 20?
16.72CAS No: 9005-64-5 Appearance: Clear, yellow to yellow-green viscous liquid Boiling point: >100 °C Brookfield Viscosity: 370-430 cps (25 °C, neat) pH of 1% aqueous solution: 5-7 Refractive index: 1.46851 Specific gravity: 1.1 HLB (hydrophile-lipophile balance) value: 16.72 CMC value3: 60 mg/l Structure: TWEEN 20 is a ...
What is the HLB system?
The HLB system, which stands for “Hydrophilic Lipophilic Balance”, indicates how the proportion of those groups will affect surfactant behavior in emulsions. HLB numbers correspond to the degree of water or oil solubility of a particular surfactant.
What is the HLB value?
Using the Griffin method, an HLB value is equal to the molecular weight percent of the hydrophilic portion divided by 5.
What is HLB in emulsion?
The HLB provides a rough guide to choosing optimal surfactants for an emulsion system.
What is the HLB method?
The HLB method is based on the premise that “all surfactants combine hydrophilic and lipophilic groups in one molecule and that the proportion between the weight percentages of these two groups for nonionic surfactants is an indication of the behavior that may be expected from that product.”
Why is it important to blend?
Blending enables formulators to target different HLB requirements and provide a wider range of solubility for cleaning and degreasing performance.
What does HLB mean in a surfactant?
HLB numbers correspond to the degree of water or oil solubility of a particular surfactant.
Which has higher HLB, linear or ethoxylate?
More specifically, a linear alcohol ethoxylate with 8 moles EO will have a higher HLB value, and better water solubility, than a linear alcohol ethoxylate with 3 moles EO.
What is HLB in chemistry?
Introduction to the HLB System. by Joseph Albanese. HLB is short for hydrophilic-lipophilic balance. Created by William C. Griffin in the late 1940s, the HLB System is one of the most successful strategies for developing stable emulsions. 1,2 Although it might not be used as much today as in the past, it still remains a valuable time-tested tool ...
How to determine the required HLB of an oil?
If the Required HLB of an oil is not in the table, it can be determined empirically by making multiple blends of high and low HLB surfactants whose ratios cover a range of HLB values, and then use them to make a series of emulsions while observing their stability.
What is the HLB of a surfactant?
The HLB values assigned to nonionic surfactants ranges between 0.5 (most lipophilic) and 19.5 (most hydrophilic). By their very nature all surfactants (surface active agents) are amphiphilic.
Is HLB a good emulsifier?
The HLB system is not without its limitations, yet it remains a good place to start. It can be a time saving approach because it eliminates many surfactants from further consideration as suitable emulsifiers for your product.
What is HLB tuning?
Tuning HLB of amphiphilic polymers is known to be a powerful tool for controlling their micellization and formation of micellar assemblies ( Azagarsamy et al., 2010; Yesilyurt et al., 2011 ). Due to the limited choice of commercially available long-chain aliphatic dicarboxylic acids, the HLB of the AIPEs-1 was primarily adjusted by varying length of the hydrophilic PEG fragment. To facilitate broader HLB tuning, a new type of polymers, amphiphilic invertible polyesters (AIPEs-2) from hydrophilic PEG and hydrophobic polytetrahydrofuran (PTHF) constituents, was developed. The use of PTHF, commercially available in a variety of molecular weights, enables better tuning of the length of the hydrophobic fragment in macromolecules, while the presence of PEG chains allows direct comparison of AIPEs-1 and AIPEs-2 in terms of the effect of macromolecular composition on micellization and other colloidal properties.
Can surfactants have the same HLB?
Not all surfactants having the same HLB value may be acceptable for a specific formulation. The overall chemical structure (branched, linear, aromatic) of surfactants is varied and is an important variable to consider. Therefore, a number of different surfactants with the required HLB should be examined. Surfactants are very versatile molecules. Depending on what emulsion type the formulator is looking for, he can balance his surfactant system so that for any formulation, one could find more than one surfactant type to give at least some of the desirable properties required.
What is the HLB system?
It is useful to correlate and measure these characteristics of the surfactants by some means for their applications in various fields such as to formulate various dispersed systems like lotions and emulsions. A common system, which is used to express the amphiphilic nature as a balance between a hydrophilic and lipophilic portion of the molecule is called as HLB system.
What is the HLB range?
The usual HLB range is from 1 to 20, while there is one exception to this range as shown in Table.1 at the bottom. Sodium lauryl sulfate, a surfactant dissolves in water very well and is a common additive to most of the heterogeneous systems and almost all common detergents. As the HLB value is additive, the blending of surfactants with known HLB values to get the desired one is very easy. The appropriate HLB values are calculated by various methods.
What is the HLB of a surfactant?
It is the number on a scale of 1 to 40, as shown in Fig.1. The HLB value for a given surfactant is the relative degree to which the surfactant is water-soluble or oil soluble. An emulsifier having a low HLB number indicates that the number of hydrophilic groups present in the molecule is less and it has a lipophilic character. For example, spans generally have low HLB numbers and are also oil soluble. Because of their oil-soluble character, spans cause the oil phase to predominate and form a w/o emulsion.
Why do tweens have higher HLB numbers?
A higher HLB number indicates that the emulsifier has a large number of hydrophilic groups on the molecule and therefore is more hydrophilic. Tweens have higher HLB numbers and are also water-soluble. Because of their water-soluble character, Tweens will cause the water phase to predominate and form an o/w emulsion.
Abstract
Essential oils are used primarily as natural preservatives, flavourants and fragrances in cosmetic products. Several pharmacopeias possess monographs of plants which are good sources of essential oils, such as Brazilian Pharmacopeia, including Illicium verum Hook. f., Schisandraceae and Rosmarinus officinalis.
Keywords
108 ISSN 0102-695X DOI: 10.1590/S0102-695X2012005000127 Received 15 May 2012 Accepted 25 Aug 2012 Available online 6 Nov 2012 Revista Brasileira de Farmacognosia Brazilian Journal of Pharmacognosy 23 (1): 108-114, Jan./Feb. 2013 HLB value, an important parameter for the development of essential oil phytopharmaceuticals Caio P.
