Formulating Hydroalcoholic Gels with Carbopol Technical ... - Lubrizol

Formulation and Manufacturing Guidelines
• Typical hand sanitizing gels contain less that 40
wt% water. Due to this formulation constraint, a
common concern is how to effectively incorporate
the Carbopol polymer. The general methods are
outlined as follows, dependent on your choice of
polymer:
Direct Method: The direct method is the traditional
method for dispersing Carbopol polymers.
Carbopol Ultrez Polymers: This method is made
easy with Carbopol Ultrez polymers since you simply
sprinkle the polymer on the surface of the water.
Allow the polymer to self wet and then begin
agitation. The general procedure is described as
follows:
1. Disperse the polymer into the water. Mix until
smooth to insure a lump free dispersion is
obtained.
2. Slowly add the alcohol with agitation and mix until
homogeneous.
3. Add emollients if desired. Keep in mind that the
order of addition may be critical to maintain
product clarity. See “Adding Emollients” for
further information.
4. Add the appropriate neutralizing agent with gentle
sweeping agitation and mix until smooth.
NOTE: If production equipment constraints require
the water and alcohol to be combined before the
dispersion of polymer, the Carbopol Ultrez polymers
must be dispersed like a traditional polymer. The
Carbopol Ultrez grade polymers will not self wet in a
solution of water and alcohol.
Carbopol Traditional Grade Polymers: These
polymers can be dispersed in either the water or
alcohol/water mixture. The polymer will swell more
slowly when added to the alcohol/water mixture, so
care must be taken to avoid the clumping and
skinning of the polymer during the dispersion
process.
1. Carefully disperse the polymer in the water or
water/alcohol mixture with good agitation. High
mixing speeds are generally preferred as it
prevents agglomeration of the polymer on the
surface of the water. Mix until the polymer is
hydrated and the dispersion is smooth and free of
lumps.
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Formulating Hydroalcoholic Gels with Carbopol ® Polymers
Page 5 of 6
2. Add the alcohol with slow mixing to de-aerate the
formulation if it was not included in Step 1.
3. Add emollients if desired. Keep in mind that the
order of addition may be critical to maintain
product clarity. See “Adding Emollients” for
further information.
4. Add the appropriate neutralizing agent with gentle
sweeping agitation and mix until smooth.
• Water Source: Use deionized water. Carbopol
polymers are sensitive to hard water ions,
therefore, the clarity and viscosity may be
negatively affected if regular tap water is used. If
deionized water is unavailable, add a chelating
agent such as tetrasodium EDTA at a level of
about 0.05-0.10% (wt/wt%).
• Adding Emollients: Several commercially
available emollients can be added to the hand
sanitizing gel to compensate for removal of oils
on the hands by the alcohol. The following watersoluble
emollients can be added directly to the
water and polymer dispersion or just before
neutralization. The use of these emollients from
0.3-0.5 wt% addition will not impact the final
product clarity.
Trade Name INCI Name
Glucam E-20 Humectant Methyl Gluceth-20
Glucam E-10 Humectant Methyl Gluceth-10
SilSense Copolyol-1 Silicone PEG-33 and PEG-8
Dimethicone and PEG-14
SilSense SW-12 Silicone Ester Dimethicone PEG-7 Cocoate
Hydramol PGPL Emollient PEG/PPG-8/3 Laurate
Hydramol PGDS Emollient PEG-90 Diisostearate
The Hydramol emollients can be added at use
levels from 0.5-3.0 wt% and still maintain good clarity
in the system.
The use of other emollients may impact the final
product clarity depending on the solubility profile of
that particular emollient. Other emollients, such as
isopropyl myristate, may need to be added to the
alcohol and the water/polymer dispersion added to
the alcohol/emollient phase to maintain final product
clarity.