INCI: Carbomer

Solubility: Water-dispersible forming a hazy solution before neutralization. Can also be dispersed in the oil phase, adding slowly while stirring.

Use rate: 0.1 – 1.0 (up to 2.0%)

pH (0.5%) in water: 2.5 – 3.5

pH stability: 6.0 – 7.0

Heat tolerance: Avoid heating above 80°C

Charge: Anionic

Compatibility: Not compatible with electrolytes, especially sodium.

Storage: The powder is hygroscopic – store airtight away from light and moisture.

TECHNICAL ASSISTANCE

Method 1:

Step 1: Rapidly agitate the water with a whisk or similar material (avoid high-shear – homogenizers or hand blenders) then add carbomer powder. Mixing should be continued until all particles are dispersed and form a hazy solution free from whitish lumps (Normal dispersion time for lab-scale batches is typically 15-20 minutes)

Step 2: Finally, neutralize with an alkaline solution (10% Sodium Hydroxide solution or 18% Potassium hydroxide solution or 30% L-Arginine solution). Neutralizer should be added a little at a time and the pH closely monitored until pH 6 is reached. Avoid manipulating the pH again to avoid an irreversible loss of viscosity. Once an alkaline solution is added to the carbomer mixture, the aqueous base will form a crystal-clear gel. At this stage, mixing with care to avoid air trapping.

Method 2:

Carbomer 940 can be dispersed in the oil phase (which may include molten waxes and oils) by adding it slowly while stirring. It will result in a smooth and homogeneous dispersion. The dispersion then should be added to the water with the neutralizer, mixing until a smooth and homogeneous emulsion is obtained.

*Add ingredients that cannot tolerate acids after neutralization.